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Impact of diet composition and temperature-humidity index on water and dry matter intake of high-yielding dairy cows
... Medical causes of depressed appetite in dairy cattle include a lack of desire for food or an inability to prehend, masticate, and/or swallow [50]. Environmental causes of depressed appetite include temperature extremes and heat stress [51]. The lack of desire for food from a nutritional aspect can be caused by acidosis [6,14,18,21,[32][33][34][35][36][37]49,52,53]. ...
... The lack of desire for food from a nutritional aspect can be caused by acidosis [6,14,18,21,[32][33][34][35][36][37]49,52,53]. Causes of depressed appetite due to factors directly related to the feed provided include low palatability (e.g., offensive smell and taste, rough appearance, inappropriate texture and feel), the presence of decomposition, endophytes, mold or mycotoxins [2,5,7,[39][40][41]51,54,55], or unfamiliarity with the offered diet [39,56]. Additionally, total dry matter intake per day (i.e., the appetite) can be affected by some physico-chemical properties of the diet, such as the fiber type and length, and content (e.g., neutral detergent fiber, NDF), digestibility of other carbohydrates, fat content of the diet, particle size, particle fragility, diet weight, rumen degradation and fermentation, passage rate through the digestive system, osmolarity of the rumeno-reticulum, and production of ruminal degradation products (e.g., concentration of various volatile fatty and other simple acids) [6,9,35,[38][39][40][41][42]49,51,[57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74]. ...
... Causes of depressed appetite due to factors directly related to the feed provided include low palatability (e.g., offensive smell and taste, rough appearance, inappropriate texture and feel), the presence of decomposition, endophytes, mold or mycotoxins [2,5,7,[39][40][41]51,54,55], or unfamiliarity with the offered diet [39,56]. Additionally, total dry matter intake per day (i.e., the appetite) can be affected by some physico-chemical properties of the diet, such as the fiber type and length, and content (e.g., neutral detergent fiber, NDF), digestibility of other carbohydrates, fat content of the diet, particle size, particle fragility, diet weight, rumen degradation and fermentation, passage rate through the digestive system, osmolarity of the rumeno-reticulum, and production of ruminal degradation products (e.g., concentration of various volatile fatty and other simple acids) [6,9,35,[38][39][40][41][42]49,51,[57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74]. For example, excess physical neutral detergent fiber in the diet can result in physical limitations caused by distention of various portions of the digestive tract (predominantly rumen and reticulum) [38][39][40]64,71,[75][76][77][78][79]. ...
The aim of this review is to provide dairy farm advisors, consultants, nutritionists, practitioners, and their dairy farmer clients with an additional toolkit that can be used in the assessment of the quality of their dairy cattle nutrition. Cow signs are behavioral, physiological, and management parameters that can be observed and measured. They are detected by examining and observing the cattle. Other physiological parameters such as fecal scoring, rumen fill, and body condition scoring are also included in ‘cow signs’. The assessment should be both qualitative and quantitative; for example, is the cattle individual lame and what is the severity of lameness. The ‘diagnosis’ of a problem should be based on establishing a farm profile of ‘cow signs’ and other relevant information. Information gathered through assessment of cow signs should be used as an advisory tool to assist and improve decision making. Cow signs can be used as part of an investigation and or farm audit.
... The dairy cattle are spread across various rearing locations with a wide range of altitudes from low to high. During its development, the macrophysical condition of the environment is no longer a primary consideration, even though the thermoneutral zone is in the range of 18-23°C (Ippolito et al. 2014;Ammer et al. 2018). Dairy cattle breeding has been developed with a direct effect on its adaptability. ...
... Previous studies have shown increased stress for livestock in low topographies with associated environmental temperature (Gehrke et al. 2013;Kamil et al. 2020;István et al. 2020). Its biological effects have been widely reported, especially the low productivity (Mushawwir et al. 2010;Hohenbrink and Meinecke-Tillmann 2012) and reproduction (Khan et al. 2015;Slimen et al. 2016;Ammer et al. 2018;Hidayat et al. 2019). Very few studies reported on the impact of altitude differences on dairy cows, including behavioral responses, physiological and biochemical responses, and growth and productivity. ...
... These changes can also be caused by continued tissue growth to increase the capacity for lipid synthesis (Tian et al. 2015). In addition, it increases metabolism due to tissue mass (Carrol et al. 2016;Ammer et al. 2018). It increases the liver mass and causes gluconeogenesis (Adriani and Mushawwir 2020;Tanuwiria and Mushawwir 2020;). ...
Tanuwiria UH, Susilawati I, Tasrifin DS, Salman LB, Mushawwir A. 2021. Behavioral, physiological, and blood biochemistry
of Friesian Holstein dairy cattle at different altitudes in West Java, Indonesia. Biodiversitas 23: 533-539. For dairy cows, the study of
physiological aspects and those related to it is very important based on altitude. The data of this study are the main considerations to
determine the ability of homeostasis, prediction of production and appropriate feed management. This study aims to examine the
behavior, physiological abilities, and blood plasma biochemistry of sixty dairy cows. It was conducted using three locations in West
Java Province based on topography, namely: (i) location with topography 350-500 meters above sea level (masl): Sukabumi Regency;
(ii) location with topography 550-750 masl: Sumedang Regency; and (iii) locations with topography > 800 masl: Bandung Regency.
Furthermore, 5 mL of blood samples were taken accurately, using a syringe and a 5 mL tube containing EDTA, respectively. Blood
sampling was taken carefully from the jugular vein of dairy cows at the beginning of every month for six sampling periods. After each
collection, the whole blood was separated from the plasma directly using a centrifuge, with a speed of 4500 ppm for 7 minutes. The
plasma obtained was used to measure the value of blood biochemistry related. The plasma analysis was conducted using a Kenza 240TX
model spectrophotometer. The procedure for analyzing blood samples followed the instructions listed in the randox and biolabo kits.
Furthermore, behavioral and thermoregulation measurements were performed every week during this research. The results showed an
increase in dairy cows' time spent lying and drinking at low altitudes compared to dairy cows at high altitudes. In contrast, rumination
and feeding activities were decreased, as shown in the blood's physiological response and biochemical profile. Dairy cows appear to be
more challenging to adjust physiologically at lower altitudes.
... Recently, a bio-capsule sensorbased ICT system (bolus system) has developed a technology that can detect changes in ruminoreticular temperature in real-time through the ICT equipment by inserting and settling it in the rumen of cows. This equipment has been used to conduct various research investigations such as investigating the changes in the concentration of milk production of cows, ruminoreticular pH, and feed intake rate etc. [1,2]. ...
... However, more detailed changes in ruminoreticular temperature were confirmed every hour compared to Cooper Prado's results [7,11]. Therefore, based on this result, it is highly valuable as a criterion for predicting of parturition time based on ruminoreticular temperature [2]. Titler et al. reported that feed and water intake are also related to the ruminoreticular temperature. ...
... Titler et al. reported that feed and water intake are also related to the ruminoreticular temperature. Therefore, there is a well-known correlation between body temperature and progesterone concentration, and it is estimated that a low temperature phenomenon occurred before delivery due to a temporary reduction in feed intake due to stress or delivery pain [2,7]. ...
How do body temperature and activity change before and after parturition in pregnant cows? Changes in body temperature such as ruminal, rectal, and vaginal temperature during the parturition have been reported, but there are no results of the simultaneous observation of body temperature and activity. The aim of this study was to simultaneously confirm changes in the ruminoreticular temperature and body activity before and after parturition using the ruminoreticular bio-capsule sensor every 1 h. The 55 pregnant cows were used for the experiment, the ruminoreticular bio-capsule sensor was inserted and stabilized, and the ruminoreticular temperature and body activity were measured. The ruminoreticular temperature was lower by 0.5° from −24 h to −3 h in parturition compared to 48 h before parturition and then recovered again after parturition. Body activity increased temporarily at the time of parturition and 12 h after parturition. Therefore, the ruminoreticular temperature and body activity before and after parturition was simultaneously confirmed in pregnant cows.
... When ambient temperature exceeds 25°C, cattle experiences HS [7]. Traditionally, temperature-humidity index (THI) is used to assess HS in dairy production [8][9][10]. THI calculations are based on dry (Tdb in °C) and wet bulb temperatures (Twb in °C)/relative humidity (RH in %). ...
... THI has been successfully employed to asses HS in the dairy cattle at various conditions of indoor or outdoor [13] different climate and production systems [14,15]. The common consensus about THI scale is the upper threshold THI, upon which the cow starts to experiences signs of hyperthermia [7,10]. This threshold has been reported variable upon different systems, generally started from 67 [16] and 72 [5,17], THI above these limits initiated hyperthermia derived discomfort [15], altered physiology [11], decreased feed intake [18], and decline in milk yield and composition [19]. ...
... When ambient temperature increases, cattle significantly increase heat production [40], therefore enhanced energy expenditure during HS is believed to originate from high physical adaptive activities like panting and sweating [41]. HS maintenance costs in lactating dairy cattle are estimated to increase by as much as 25% to 30% during heat stress [10,42]. However, due to a variety of acclamatory responses and depending on the severity and intensity of the HS, it will vary significantly. ...
Simple Summary: Modern dairy cows have elevated internal heat loads caused by high milk production, and the effects of accumulating incremental heat are exacerbated when temperature and humidity increases in the surroundings. To shed this additional heat, cows initiate a variety of adaptive mechanisms including increased respiration rate, panting, sweating, reduced milk yield, vasodilatation, and decreased reproductive performance. Hormonal changes based on reciprocal alterations to the energetic metabolism are particularly accountable for reduced efficiency of the dairy production under the heat stress. As animals experience negative energy balance; glucose, which is also a precursor of milk lactose, becomes the preferential energy fuel. In the absence of proper mitigations, heat stress possesses potential risk of economic losses to dairy sector. Besides physical measures for the timely prediction of the actual heat stress coupled with its proper amelioration, nutritional mitigation strategies should target modulating energetic metabolism and rumen environment. Abstract: Higher milk yield and prolificacy of the modern dairy cattle requires high metabolism activities to support them. It causes high heat production by the body, which coupled with increasing environmental temperatures results in heat stress (HS). Production, health, and welfare of modern cattle are severely jeopardized due to their low adaptability to hot conditions. Animal activates a variety of physiological, endocrine, and behavioral mechanisms to cope with HS. Traditionally, decreased feed intake is considered as the major factor towards negative energy balance (NEBAL) leading to a decline in milk production. However, reciprocal changes related to insulin; glucose metabolism; failure of adipose mobilization; and skeletal muscle metabolism have appeared to be the major culprits behind HS specific NEBAL. There exists high insulin activity and glucose become preferential energy fuel. Physiological biochemistry of the heat stressed cows is characterized by low-fat reserves derived NEFA (non-esterified fatty acids) response, despite high energy demands. Besides these, physiological and gut-associated changes and poor feeding practices can further compromise the welfare and production of the heat-stressed cows. Better understanding of HS specific nutritional physiology and metabolic biochemistry of the dairy cattle will primarily help to devise practical interventions in this context. Proper assessment of the HS in cattle and thereby applying relevant cooling measures at dairy seems to be the basic mitigation approach. Score of the nutritional strategies be applied in the eve of HS should target supporting physiological responses of abatement and fulfilling the deficiencies possessed, such as water and minerals. Second line of abatement constitutes proper feeding, which could augment metabolic activities and synergizes energy support. The third line of supplemental supports should be directed Animals 2020, 10, 793 2 of 20 towards modulating the metabolic (propionates, thiazolidinediones, dietary buffers, probiotics, and fermentates) and antioxidant responses (vitamins). Comprehensive understanding of the energetic metabolism dynamics under the impact of incremental heat load and complete outlook of pros and cons of the dietary ameliorating substances together with the discovery of the newer relevant supplementations constitutes the future avenues in this context.
... As THI increased, dairy cows spent more time at the drinker, visited the drinker more often, increased water intake, and engaged in more competitive behavior at the drinker. In addition to contributing to the literature that shows that dairy cows increase their drinking behavior (Ammer et al., 2018) and become more aggressive (Pilatti et al., 2019) when hot, the results of this study suggest that socially subordinate cows may be more vulnerable to increasing THI, as they shifted their drinking behavior to different times of the day. ...
... Temperature is well known to be associated with water intake in dairy cows (Murphy et al., 1983;Meyer et al., 2004;Cardot et al., 2008). Other studies have found that drinking time (Cook et al., 2007), frequency (Ammer et al., 2018), and intake (McDowell et al., 1969;Beatty et al., 2006;Ammer et al., 2018) increase with increasing THI and ambient temperature. Body water is lost as a result of panting and sweating (Kadzere et al., 2002), and ingestion of water increases heat loss and combats dehydration (Vizzotto et al., 2015). ...
... Temperature is well known to be associated with water intake in dairy cows (Murphy et al., 1983;Meyer et al., 2004;Cardot et al., 2008). Other studies have found that drinking time (Cook et al., 2007), frequency (Ammer et al., 2018), and intake (McDowell et al., 1969;Beatty et al., 2006;Ammer et al., 2018) increase with increasing THI and ambient temperature. Body water is lost as a result of panting and sweating (Kadzere et al., 2002), and ingestion of water increases heat loss and combats dehydration (Vizzotto et al., 2015). ...
Heat-stressed dairy cows on pasture will compete for resources that aid cooling, but it is not known how heat stress affects the competition for water by indoor-housed cows. The aim of this observational study was to evaluate how heat stress affects the behavior of indoor-housed cows at the drinker at both group and cow levels. For 3 wk after calving, cows were housed in a dynamic group of 20 animals in a pen with 12 electronic feed bins, 2 electronic water bins, and 24 freestalls. A total of 69 lactating Holstein dairy cows were enrolled over the 59-d study. The electronic water bins recorded time spent at the drinker, frequency of visits, water intake, and competitive events for 24 h/d. Competitive events were quantified using the number of replacements (recorded when there was a ≤29-s interval between 2 cows sequentially visiting the same drinker). The number of replacements a cow was involved in was used to determine her level of competitive success at the drinker (low, medium, high). The temperature-humidity index (THI) was recorded by the local weather station, and moving averages for daily maximum THI over a 3-d period were calculated. For the analysis of time spent at the drinker, frequency of visits, and water intake, the measures from all cows were averaged to create 1 observation per day, and the number of replacements at the drinker was summed. A linear regression was performed to determine the relationship between THI and group-level drinking behavior. At the cow level, a repeated measures mixed model, with fixed effects of level of competitive success, milk yield, and 3-d maximum THI and a first-order autoregressive covariance structure, was used to determine how increasing THI affects the drinking behavior of individual cows based on their level of competitive success. Feed intake was included as a fixed effect in the water intake model. We found that, with increasing THI, cows drank more water, spent more time at the drinker, made more visits to the drinker, and engaged in more competitive events at the drinker. In exploratory analysis, we found that cows with low competitive success at the drinker shifted their drinking behavior to avoid the drinker at the hottest and most competitive time of day. These results indicate that behavior can be used to indicate when cows feel hot. These measures may be of practical value in deciding when to provide cooling, especially for farms where attendance at the drinker can be monitored electronically.
... When the THI reaches above the threshold level (> 72) it will lead to hyperthermia-associated discomfort, changes in normal physiological responses, reduced feed intake, and a decline in milk yield [8] . The diet and THI will have an effect on the water intake and DMI in heat-stressed animals [9] . So, the careful measurement of THI along with the physiological parameters like RR, PR, and RT will help in assessing the effect of HS on dairy cows. ...
... Heat-stressed cows will show certain behavioural and physiological changes including modified feeding and drinking behaviour, as a result, animals will prefer to consume feed during cooler hours and drink water at frequent intervals. HS is expected to result in an increase in maintenance costs of up to 25% to 30% in lactating dairy cows [9] . In addition to the behavioural and physiological changes, thermal stress also causes hormonal changes through the hypothalamus-pituitaryadrenal axis, by releasing glucocorticoids and aldosterone. ...
The livestock sector provides a consistent income to the farmer and acts as a backbone of the national economy along with agriculture and in the near future, this sector will become the major source to provide nutritional security (meat and milk) for the growing population. But the changing climate scenario and global warming are increasing the effect of Heat stress (HS) on animals and it becomes a severe threat to sustainable livestock production. HS compromises the growth, production, and reproduction efficiency of dairy cattle and will cause severe economic losses to the dairy farmer. The adverse effects of HS can be minimized by three types of interventions including genetic manipulation, nutritional interventions, and management practices that help the dairy cow to sustain production and reproduction in hot weather. Among these, nutritional strategies are simple and cost-effective in preventing the adverse effects of HS. This article will discuss various nutritional strategies such as the provision of ad libitum cold water, quality protein, fat, minerals, vitamins, and other feed additives necessary for dairy cows to cope with HS and sustain productivity in dairy cows.
... On the other hand, a water intake of 146 g per gram of ingested sodium (52) was found in absence of a thermal insult. In dry cows without heat stress, water intake is significantly lower (15 to 61 L/d) (53) , but increases by 27 % with the onset of milk production during the early lactation (54) . ...
... Dairy cows can experience severe dehydration when they lose 12 % of their body weight due to lack of water intake; such dehydration can be lethal if the total body water loss reaches approximately 20 % (55) . Given that HS increases water loss in ruminants considerably, its intake at adequate levels becomes critical for dairy cows (54) . In warm areas, water intake can increase between 10 and 20 % during the summer, when even a cow classified as low producing can drink more than 100 L/d (32) . ...
El impacto negativo del estrés por calor (EC) en la ganadería lechera repercute en cuantiosas pérdidas económicas a nivel mundial, dado que reduce la producción de leche, la eficiencia reproductiva y la vida productiva de las vacas. Adicionalmente, el mejoramiento genético continuo resulta en vacas muy productivas, pero menos tolerantes al EC debido a que producen mayor calor metabólico. Esto en conjunto con el calentamiento global convertirá al EC en un reto difícil de controlar para la industria lechera. Como respuesta dependiente del grado de EC, el ganado lechero realiza una serie de ajustes fisiológicos, metabólicos y conductuales como mecanismos de termorregulación para disipar el exceso de calor corporal y reducir la producción endógena del mismo, todo dirigido a mantener la normotermia. Sin embargo, la secreción láctea y la fertilidad se reducen por efecto directo de la hipertermia e indirectamente por la reducción en el consumo de nutrientes dietéticos. Los consumos de alimento y de agua están asociados estrechamente con la reducción de la productividad en ganado lechero expuesto a EC. Cabe mencionar que el impacto del EC en la productividad del ganado lechero varía entre razas, siendo las razas Bos taurus menos tolerantes al EC, particularmente la raza Holstein. Actualmente, se investiga en la identificación de genes asociados con la termotolerancia, los cuales son empleados en programas de selección por marcadores genéticos para producir vacas altas productoras de leche en climas cálidos. Por lo tanto, el objetivo de esta revisión es hacer un análisis comprensivo de los efectos del EC sobre la producción de leche, activación de mecanismos de termorregulación y conducta de ingesta en ganado lechero.
... The temperature-humidity index is used to assess heat stress in dairy production (Sammad et al., 2020;Ammer et al., 2018;Wildridge et al., 2018). According to Pinto et al. (2020), when THI exceeds a threshold value of 72, heat stress begins for dairy cattle. ...
... A THI above 72 results in hyperthermia-derived discomfort, altered physiology and a decline in milk yield and composition (Herbut et al., 2018;(Kadzere et al., 2002). The degree to which the cows are stressed also increases with the THI (Ray et al., 2004, Ammer et al., 2018. But thermal stress may manifest differently for physiological measures, with RR being affected at a lower THI and RT increasing at a higher THI (Pinto et al., 2020). ...
This study was conducted to investigate the effect of heat stress on the physiology of dairy cows and to detect the relationship between rectal temperature (RT) and respiration rate (RR), heart rate (HR), and plasma concentrations of cortisol, thyroxine, and prolactin. During the experiment, 44 Holstein cows were allocated to two groups for each season. The average temperature-humidity index (THI) values were 55 ± 2.31 in winter and 78 ± 1.9 in summer. As the THI values increased from 55 to 78, RR rose by 35 inspirations per minute, HR by 3 beats per minute, and RT by 1.2 °C. In addition, the average concentration of cortisol increased from 19.30 to 21.04 nmol/L, and prolactin from 58.52 to 129.79 ngm/L, whereas free thyroxine decreased from 15.43 to 14.01 pmol/L. Plasma sodium and potassium concentrations were similar in the two seasons. These results confirmed that RT is an indicator of the response in dairy cows to hot environmental temperatures. However, they also showed signs of stress, which were reflected in higher levels of cortisol and in certain physiological responses. ______________________________________________________________________________________
... THI at r = 0.238 (p < 0.05), whereas there was no significant correlation found between the temperature, RH, or THI value and the organic feed. The positive correlations of temperature and THI with conventional milk yield in this study indicate that milk yield increases with increasing temperature and THI, contrary to the findings of other studies that reported that increased heat stress leads to a reduction in milk production in dairy cows due to a decrease in feed intake (Ravagnolo et al., 2000;Ammer et al., 2018). It should be noted that the highest THI value recorded during the experimental period was in June at 69.5, which is less than the THI value of 72, the point where cows normally experience mild heat stress (Armstrong, 1994). ...
... The THI is most often used as an environmental index to evaluate heat stress in dairy production (Bohmanova et al., 2007;Ammer et al., 2018). Armstrong (1994) demonstrated that cows do not experience heat stress with THI values less than 72, experience mild heat stress when THI values are at 73 -79, suffer moderate heat stress when THI is at 80 -89, and exhibit severe heat stress when THI is higher than 90. ...
This study aimed to determine the effects if ambient temperature (Ta), relative humidity (RH), and temperature-humidity index (THI) on milk production parameters such as milk yield, fat, protein, milk urea nitrogen (MUN), and lactose. A total of fifty (50) mid-lactating Korean Holstein cows (144-150 days postpartum) were randomly assigned to two groups in equal numbers (n = 25) according to the type of diet received: conventional feed, a mixture of 56: 44 ratio of roughage and concentrate mix, and organic feed containing 100% organic roughage. Temperature, RH, and THI were recorded daily and averaged monthly. Conventional group showed higher dry matter intake throughout the experiment and thus, showed higher total milk yield and milk composition such as milk fat, protein, and lactose content than organic milk. Milk of the conventional group showed higher polyunsaturated fatty acid concentration. Highest milk yield was observed in September (21.7℃, 82.4%RH) in conventional group (27.69 kg·day-1) and in June (21.4℃, 72.9%RH) in organic group (14.31 kg·day-1). In conventional group, milk yield was positively correlated with Ta and THI, and milk protein was negatively correlated with Ta, RH, and THI. In organic feeding, only the MUN among milk composition parameters showed a significant correlation where it showed a negative correlation with Ta, RH, and THI. Conventional feeding showed significantly higher milk yield, fat, protein, and lactose than organic feeding throughout the experiment, although, organic feeding showed to be less likely affected by Ta, RH, and THI than the conventional feeding.
... Recently, a technology has been developed to detect temperature changes in real-time by inserting a sensor into the rumen of a cow through the bolus system. Various studies using implantable sensors to detect change in milk production, ruminal pH, feed intake rate, and vaccination have been conducted (Gasteiner et al., 2012;Gasteiner et al., 2015;Kim et al., 2017a;Ammer et al., 2018;Villot et al., 2018). ...
... Use of thermometers, the most common method of measuring core body temperature, is limited and cannot be used to measure body temperature in real-time. Several wearable sensors have been developed for real-time monitoring of cattle body temperature (Gasteiner et al., 2012;Gasteiner et al., 2015;Kim et al., 2017a;Ammer et al., 2018). Therefore, the aim of this study was to record the daily body temperature throughout the pregnancy period using a ruminal wearable sensor, and to investigate the differences in body temperature between pregnant and nonpregnant cows. ...
In recent years, various methods of measuring body temperature have been developed using wireless biosensors to facilitate an early detection of pregnancy and parturition in cows. However, there are no studies on real-time monitoring of cattle body temperature throughout pregnancy. Therefore, we investigated the daily mean ruminal temperature in pregnant cows throughout pregnancy using a ruminal bio-capsule sensor and then evaluated the temperature variation between pregnant and non-pregnant cows. In pregnant cows, the mean and standard deviation of ruminal temperature was 38.86 ± 0.17℃. Ruminal temperature in pregnant cows slowly decreased until 180 to 190 days after artificial insemination and after that, the temperature increased dramatically until just before parturition. Furthermore, the means ruminal temperature was significantly different between pregnant and nonpregnant cows. The mean and standard deviation of ruminal temperature were as follows: 38.68 ± 0.01℃ from days 80 to 100, 38.78 ± 0.02℃ from days 145 to 165, 38.99 ± 0.45℃ from days 200 to 220, 39.14 ± 0.38℃ from days 250 to 270 before parturition. Therefore, our results could provide useful data for early detection of pregnancy and parturition in Korean cows.
... This index can complement decision support system by offering a concise measure of environmental data to monitor stress indicators. Moreover, ref. [106] observed that drinking frequency increased consistently, i.e., from 0.12 to 0.23 l/THI, throughout a range of THI increasing from 51.4 to 79.7. Additionally, changes in drinking patterns were observed between different troughs based on the dominance hierarchy of the cows, with a seasonal correlation of drinking time with THI [107]. ...
Simple Summary
Next-generation numerical approaches, such as machine learning techniques and big data analytics, are also increasingly applied in the animal production sector. Still today, one of the most investigated matters in the dairy cow sector is the detection and the evaluation of the effects induced by heat stress condition. This review provides, in a single document, an overview, as complete as possible, of the heat stress-induced responses in dairy cattle aiming to transfer the wide veterinary knowledge available in the literature to researchers and technicians who are developing numerical models and decision support system tools.
Abstract
In the dairy cattle sector, the evaluation of the effects induced by heat stress is still one of the most impactful and investigated aspects as it is strongly connected to both sustainability of the production and animal welfare. On the other hand, more recently, the possibility of collecting a large dataset made available by the increasing technology diffusion is paving the way for the application of advanced numerical techniques based on machine learning or big data approaches. In this scenario, driven by rapid change, there could be the risk of dispersing the relevant information represented by the physiological animal component, which should maintain the central role in the development of numerical models and tools. In light of this, the present literature review aims to consolidate and synthesize existing research on the physiological consequences of heat stress in dairy cattle. The present review provides, in a single document, an overview, as complete as possible, of the heat stress-induced responses in dairy cattle with the intent of filling the existing research gap for extracting the veterinary knowledge present in the literature and make it available for future applications also in different research fields.
... As pesquisas de Burfeind et al. (2012) As aferições das temperaturas ruminal e reticular também são consideradas como métodos invasivos, havendo na maioria dos casos a necessidade de cirurgias (fistulas) para a colocação das "pílulas" de leitura, fatores à contramão do BEA (AMMER et al., 2018). Mesmo com a criação de equipamentos e "pílulas" para colocação via oral (método menos invasivo), poucos são os resultados, fazendo deste método um modelo ainda não tradicional para a realidade dos criadores, principalmente em regiões menos desenvolvidas ou em países como o Brasil (KNAUER;GODDEN;MCDONALD, 2016;KOLTES et al., 2018). ...
... As pesquisas de Burfeind et al. (2012) As aferições das temperaturas ruminal e reticular também são consideradas como métodos invasivos, havendo na maioria dos casos a necessidade de cirurgias (fistulas) para a colocação das "pílulas" de leitura, fatores à contramão do BEA (AMMER et al., 2018). Mesmo com a criação de equipamentos e "pílulas" para colocação via oral (método menos invasivo), poucos são os resultados, fazendo deste método um modelo ainda não tradicional para a realidade dos criadores, principalmente em regiões menos desenvolvidas ou em países como o Brasil (KNAUER;GODDEN;MCDONALD, 2016;KOLTES et al., 2018). ...
... As pesquisas de Burfeind et al. (2012) As aferições das temperaturas ruminal e reticular também são consideradas como métodos invasivos, havendo na maioria dos casos a necessidade de cirurgias (fistulas) para a colocação das "pílulas" de leitura, fatores à contramão do BEA (AMMER et al., 2018). Mesmo com a criação de equipamentos e "pílulas" para colocação via oral (método menos invasivo), poucos são os resultados, fazendo deste método um modelo ainda não tradicional para a realidade dos criadores, principalmente em regiões menos desenvolvidas ou em países como o Brasil (KNAUER;GODDEN;MCDONALD, 2016;KOLTES et al., 2018). ...
... 1Y=1,87-0,08x+0,004x 2 (R 2 =0,99); 2Y=46,82-1,87x+0,10x 2 (R 2 =0,99). overall (Ammer et al., 2018). The toxic by-products of protein digestion for energy must be eliminated from the body. ...
The objective was to investigate how different levels of soybean meal replacement with extruded urea (EU) in
sheep supplementation affected pasture characteristics (Brachiaria spp.), consumption, ingestive behavior and
animal performance. Sixty Texel crossbred lambs were randomly divided between treatments: 0, 6, 12, 18 and
24 g of 100 kg− 1 body weight (BW) EU supplement under continuous stocking in Brachiaria spp. The animals
receiving a supplement in the proportion of 24 g 100 kg− 1 BW from the EU had the highest pasture height (39.5
cm) as compared with other treatments. The levels of replacement of soybean meal by the EU had no effect on the
supply of forage, forage accumulation rate or structural characteristics. The forage dry matter intake (DMI) as
percentage of BW and metabolic BW were adjusted to quadratic equations, and the minimum levels of DMI in
relation to BW (1.5 %) and metabolic (55.6 g DM/kg0.75) were estimated at 10 g and 9.4 g 100 kg− 1 BW of the
EU, respectively. The grazing time of the lambs decreased linearly (P = 0.006) by 4.88 min for each increase in
the EU level. In contrast, as EU levels in lamb supplementation increased, the time taken to consume the supplement and the bite rate increased by 4.38 min and 0.28 bites/minutes, respectively. The average daily gain
increased linearly up to 18 g 100 kg− 1 BW (146 g/day) (P = 0.034). For lambs finishing in Brachiaria spp., the EU
can be used in place of soybean meal up to 18 g 100 kg-1 BW without altering animal performance, consumption,
or the structural characteristics of the pasture.
... Here, the shape of the DON residues in blood at a steady state depends mainly on the meal size and meal frequency, representing the dose and administration intervals, respectively. When TMR is offered for ad libitum consumption, the meal frequency varies, for example, between 31 and 56 bouts/day depending on diet type, whereby meal intervals are not equidistant, and meal sizes fluctuate between 0.4 and 0.7 kg/bout [32]. Therefore, the oscillation of DON residue concentrations in blood at a steady state, as depicted in Figure 5, is an idealized one but will differ in magnitudes for peak and trough levels among individual animals depending on their eating behavior. ...
Evaluation of dairy cow exposure to DON can generally be managed through analyses of feed or physiological specimens for DON residues. The latter enables a diagnosis not only on an individual basis but also on a herd basis. For this purpose, on the basis of published data, linear regression equations were derived for blood, urine, milk, and bile relating DON residue levels as predictor variables to DON exposure. Amongst the matrices evaluated, blood was identified to reflect the inner exposure to DON most reliably on toxicokinetic backgrounds, which was supported by a linear relationship between DON residues in blood and DON exposure. On the basis of this, and because of extended blood data availability, the derived regressions were validated using internal and external data, demonstrating a reasonable concordance. For all matrices evaluated, the ultimately recommended linear regression equations intercepted the origin and enabled the prediction of the DON exposure to be expected within the prediction intervals. DON exposure (µg/kg body weight/d) can be predicted by multiplying the DON residues (ng/mL) in blood by 2.52, in urine by 0.022, and in milk by 2.47. The span of the prediction intervals varied according to the dispersion of the observations and, thus, also considered apparent outliers that were not removed from the datasets. The reasons were extensively discussed and included toxicokinetic aspects. In addition, the suggestions for sample size estimation for future characterization of the mean exposure level of a given herd size were influenced by expectable variation in the data. It was concluded that more data are required for all specimens to further qualify the preliminary prediction equations.
... When considering the days of greatest discomfort (> H), which in this case were days 23, 24, and 25, milk production in both groups of animals decreased in comparison to the days of lower enthalpy, which means the amount of heat existing in a CB system directly influences the production. Among the several factors that can cause a drop in milk production in dairy cattle, heat stress is quite participatory, mainly because the animal in hyperthermia has difficulties in dissipating body heat, with adaptive changes such as a drop in feed intake in order to reduce the production of metabolic heat; however, it generates less energy destined for milk production (Ammer et al. 2017). This fact will consequently affect the animal behavior, as discussed above, its time spent standing or lying down as a way to improve heat exchanges in the environment in which it is inserted. ...
The compost barn is presented as a system which is capable of providing a suitable environment for dairy cows, but this must be assessed for different climatic regions. Few studies have been carried out evaluating the physics of the thermal environment of this system under tropical conditions. In this study, we evaluated thermoregulatory, behavioral, and productive responses and physical integrity in primiparous and multiparous cows housed in a compost barn system under tropical conditions. From a total of 121 clinically healthy dairy cows aged 3 to 6 years, 30 Girolando cows (7/8) were randomly selected, divided into two groups, according to calving order (primiparous and multiparous), body weight, lactation curve and milk production for the evaluations. Thus, group 1 (primiparous) with an average weight of 524 kg and production of 30 kg was characterized, and group 2 (multiparous) with an average weight and production of 635 kg and 36 kg, respectively. The enthalpy was higher (P < 0.05) in the internal environment of the shed at the three evaluated times (3:30 a.m., 11:30 a.m., and 6:30 p.m.), but the humidity did not vary (P > 0.05) between the internal and external environments at the evaluated times. Respiratory rate was higher (P < 0.0001) in multiparous cows at 11:30 a.m., but was similar at 3:30 a.m. and 6:30 p.m. when compared with primiparous cows. The coat surface temperature was higher (P < 0.001) at 3:30 a.m., but similar at the other two times. For the variables lameness and dirtiness, the vast majority of animals presented scores considered adequate (1 and 2), indicating that it was able to provide an ideal physical environment. Regarding animal behavior, panting (O) and lying idle (OD) were higher (P < 0.05) in multiparous cows. Multiparous cows have higher (P < 0.0001) milk production. Milk production has a negative correlation with enthalpy. The CB system was not able to provide a suitable thermal environment for the animals. Multiparous cows present higher heat stress with change in behavioral responses, especially at midday, but with higher milk production when compared to primiparous cows in compost barn under tropical conditions.
... Bouraoui et al. (2002) observed that daily THI was negatively consistent with milk production (r =-0.76) and feed intake (R = -0.24.). As previously mentioned, heat stress leads to a decrease in the feed intake of dairy cows (Ammer et al., 2018). Heat stress may be the cause of decreasing milk production because of low nutrient intake and uptake by the portal drained viscera of the cow. ...
Climate changes affect the economic viability of livestock. Therefore, this study aimed to characterize the heat stress in Holstein cattle raised in the arid region of Tunisia as well as to evaluate the effect of the temperature-humidity index (THI) on daily milk production and components. For this reason, 76940 monthly individual records collected from 1995 to 2018 from 3056 Holstein cows were used. THI calculated from ambient temperature and relative humidity was used as a measure of heat stress. To study the effect of THI on milk production, a repeated measures linear mixed model was used. Results showed a significant (P<0.01) decrease in daily milk yield, daily protein, and fat content in all cow's parity classes. For each point increase of the THI values beyond 64, milk yield, fat, and protein contains decreased by 0.32 kg, 0.09, and 0.06 %, respectively. Moreover, when the THI value varied from 64 to 85, fat content decreased by 29 %, protein by 17 %, and milk production by 30 %. Heat stress impact negatively milk production and milk components of dairy cows. These results can be a way to improve the length of productive life for Holstein dairy cattle in the hard climate. Serious management strategies are needed to improve dairy cow productivity and minimize the heat stress impact.
... However, Zanetti et al. (2019) observed a lower water intake (16.7 ± 6.5 L/head/day) in Nellore cattle. Instead, in addition to breed, water intake in cows is influenced by different factors such as DM intake, production system, and age of the animal (Ammer et al., 2018). ...
Worldwide, dairy sector consumes 19% of the water in the livestock sector. However, in Latin America, the amount of water used in this sector is unknown, especially in arid zones. On the other hand, water footprint (WF) is a methodology to estimate the use of water to produce a product. The aim of this work was to estimate the WF of dairy production in the arid zone of the Peruvian central coast. Data from five dairy farms were used. The WF was calculated in its three dimensions: green water, blue water and grey water. In addition, the WF was measured for categories: feed, drinking and service. To measure the WF of feed production, the CROPWAT software was used, whilst the NRC (2001) equations were used to estimate the drinking water. The reference unit was cubic metres per kilogram of fat and protein corrected milk (FPCM). In average, 99% of the WF comes from feed production, followed by drinking water (0.4%). From the three dimensions of the WF, green water is responsible of 60% of the WF, followed by the blue water (30%). Imported water represented 63% of the WF. In general, WF of dairy production in these systems was 0.66 m3/kg FPCM. In conclusion, feed production, as the main source of WF from which most is imported, shows the possibility of reducing the WF of these systems by prioritizing and optimizing water consumption by crops using local resources with lower water requirements.
... The growth of these villi is stimulated due to the presence of glutamyl cysteine protein, which plays a role in increasing protein anabolism. Ammer et al., (2018); Kamil et al. (2020);Carrol et al. (2016) and Dinana et al. (2019) have indicate that naturally, glutathione contains high levels of glutamyl and cysteine. ...
This research has been carried out for a month using eighty three-month-old female Cihateup ducks and has been used to study the influence of glutathione on the endogen antioxidant response and histological illeum. The separation of glutathione was carried out using the distillation technique. Each experimental group consisted of 20 ducks, each treated with G0 = without glutathione; G1= Administration of glutathione 150 µL/head; G2 = Administration of glutathione 175 µL/head; G3= Administration of glutathione 175 µL/head. Tissue and blood sampling was collected at the end of the study by EDTA tube and a fixative solution, and tissue preparations were made using the Mallory-Asan technique and analyzed using a binocular microscope. Antioxidant levels were measured using a spectrophotometer technique based on the instructions of the Randox Kit. The results showed that glutathione affected (P<0.05) morphometric ileum (villi, Peyeri's plaque and goblet cells) and increased with increasing glutathione level and endogenous antioxidant response. It was concluded that glutathione is able to stimulate protein and lipid anabolism, as well as hormonal signals related to ileal tissue growth and antioxidants.
... Therefore, the variation of results between studies is common to occur. Ammer et al. (2017) observed that the variation in the dry matter content of the diet, silage type, and concentrate ratio might have influenced the water intake of cattle on a feedlot. Hicks et al. (1988) observed that average daily water consumption was positively related to average daily maximum temperature and average daily dry matter intake. ...
It is important to understand the relationship between beef cattle water performance and animal welfare. However, to date, there is no knowledge of studies carried out to assess the water productivity of cattle when using an animal welfare practice. This study aimed to evaluate the impact of artificial shading in the water intake and water productivity and the relationships between these indicators with animal performance and water cost in a cattle feedlot system. Animals were divided into two groups, with shade (GS) and without shade (GWS), and they were housed in four collective pens. Water intake (WI, L day⁻¹), dry matter intake (DMI, kg day⁻¹), and average daily gain (ADG, kg day⁻¹) were obtained for all cattle individually. To calculate water productivity, water input was the direct technical water represented by animal drinking. The average daily water intake for animals under shade was 36.8 L day-1. Animals without shade consumed 9% (3.3 L day⁻¹) more water than animals under shade. Animals under shade presented higher water productivities. The average water productivity per kilograms of live weight of animals under shade was 0.203 kg LW L⁻¹ water, with a maximum of 0.264 kg LW L⁻¹ water and a minimum of 0.159 kg LW L⁻¹ water. These values were 0.185, 0.234, and 0.097 kg LW L⁻¹ water, respectively, for animals without shade. This is justified due to the lower average water intake for these animals and due to the numerically higher live weight and carcass weights. The results showed that if a production system uses shade in the feedlot, the water payment could be reduced by 7.2%. The study demonstrated that animals had a benefit by being produced with better welfare, the environment has a benefit by producing the same output with less water input, and the consumer wins by having an available product with environmental and animal welfare values.
... Most previous studies that identified positive deviants relied on a single performanceindicator variable to classify a group of outperforming farms in a sample obtained in a cross-sectional survey [30]. Given the complexity of the livestock production systems that smallholders manage, where farmers pursue multiple objectives, there is likely no one single best indicator variable of performance suited for an objective identification of positive deviants. ...
In smallholder dairy-cattle farming, identifying positive deviants that attain outstanding performance can inform targeted improvements in typical, comparable farms under similar environmental stresses. Mostly, positive deviants are identified subjectively, introducing bias and limiting generalisation. The aim of the study was to objectively identify positive deviant farms using the Pareto-optimality ranking technique in a sample of smallholder dairy farms under contrasting stressful environments in Tanzania to test the hypothesis that positive deviant farms that simultaneously outperform typical farms in multiple performance indicators also outperform in yield gap, productivity and livelihood benefits. The selection criteria set five performance indicators: energy balance, disease-incidence density, daily milk yield, age at first calving and calving interval. Findings proved the hypothesis. A few farms (27: 3.4%) emerged as positive deviants, outperforming typical farms in yield gap, productivity and livelihood benefits. The estimated yield gap in typical farms was 76.88% under low-stress environments and 48.04% under high-stress environments. On average, total cash income, gross margins and total benefits in dairy farming were higher in positive deviants than in typical farms in both low- and high-stress environments. These results show that the Pareto-optimality ranking technique applied in a large population objectively identified a few positive deviant farms that attained higher productivity and livelihood benefits in both low- and high-stress environments. However, positive deviants invested more in inputs. With positive deviant farms objectively identified, it is possible to characterise management practices that they deploy differently from typical farms and learn lessons to inform the uptake of best practices and extension messages to be directed to improving dairy management.
... High air temperature and humid climate lead to an imbalance between the metabolic heat output inside the animal body and its dissipation to the surroundings resulting in heat stress (Das et al. 2016). Cows decrease their feed intake to mitigate heat stress (Ammer et al. 2018) thereby leading to a gradual decline in milk production (Liu et al. 2019). Heat stress has several direct and indirect effects on dairy animal health. ...
A study was carried out for a period of 90 days during the summer season with the inclusion of chromium
propionate and vitamin E with selenium, in the feed to investigate their effect on 24 uniparous lactating Holstein
Friesian cows in an early phase of lactation. Cows were randomly assigned to four supplemental doses of 0 (T0);
500 IU/animal/day of vitamin E and 0.3 mg/kg DM of selenium (T1); 0.5 mg/kg DM of chromium propionate (T2)
and 0.5 mg/kg DM of chromium propionate, 500 IU/animal/day of vitamin E and 0.3 mg/kg DM of selenium (T3).
The mean THI value in the morning was 75.10±0.42 and 80.01±0.64 in the afternoon indicating that the animals were
under mild to moderate heat stress. Increase in the DMI was found in the supplemented groups with a significant
difference between control and T3 group. Milk yield differed significantly between the control and supplemented
groups. The hematological profile did not vary significantly among the groups. Supplementation of chromium along
with vitamin E and selenium decreased the cortisol level and glutathione peroxidase activity signigicantly in the
T3 group. Chromium supplemented groups (T2 and T3) showed greater increase in mean total protein, albumin
concentration and A/G ratio. However, the mean values for thyroid profile, liver enzymes, superoxide dismutase,
catalase, globulin, total cholesterol, triglycerides, glucose, urea, creatinine were comparable among the four groups.
Statistical analysis revealed that the rectal temperature, respiratory rate, and pulse rate in supplemented groups were significantly reduced. The findings showed that chromium supplementation plays a significant role in alleviating thermal stress and is further more beneficial when supplemented with proven antioxidants vitamin E and selenium.
... With increasing summer temperatures, heat stress is likely to affect dairy cow productivity more frequently, even in temperate climate regions (Armstrong, 1994;Fodor et al., 2018). Heat stress negatively affects dairy cattle welfare and productivity in multiple ways, including reduced feed intake, and increased body temperature and respiratory rate, as cows cope with high environmental temperatures and humidity (Armstrong, 1994;Bernabucci et al., 2014;Ammer et al., 2018). ...
This paper assesses the influence of heat and drought stress on the economic performance of the European dairy sector. Climatic data from the Gridded Agro-Meteorological data in Europe were combined with dairy enterprise data from the Farm Accountancy Data Network, resulting in a data set of 4412 farms in 22 European Union (EU) countries over the period 2007–2013. Since the performance of dairy farms is influenced by the context in which they operate, farms were grouped into areas representing similar climatic conditions through the use of a latent class analysis. Technical efficiency (TE) and economic downside risk were used as performance indicators against which the effect of climatic stress factors was evaluated. TE was estimated using a ‘true-fixed’ effect stochastic frontier model. Economic downside risk was based on gross margin deviations. Regression analysis suggests a significant negative effect of drought and heat stress on both TE and the downside gross margin difference in most climatic classes, with few exceptions. Results imply that both drought and heat stress-related issues need to be considered when designing adaptation strategies to address threats to the economic performance of the EU dairy sector.
... Já a digestibilidade de matéria seca (DMS) apresentou resposta quadrática, onde o grupo que consumiu 100% de silagem de milho (100S) adquiriu a maior porcentagem perante os demais (Tabela 2). De acordo com Ammer et al. (2017), o CMS dos animais pode ser influenciado pela granulometria e teor nutricional da dieta sobre o enchimento ruminal e, efeitos fisiológicos consequentes do fornecimento energético da ração. Já segundo Costa et al. (2014), o esvaziamento ruminal é um dos principais estímulos alimentares. ...
The objective was to evaluate effects of extruded soybean hulls as replacement for corn silage. Twenty animals with an average weight of 57.00kg were used. The treatments consisted different levels inclusion the extruded roughage to replace the silage. A completely randomized design was used. There was negative linear response for dry matter intake, weight of feces in dry matter, efficiency ingestion, chewing and rumination and urea. Dry matter digestibility showed a quadratic response. The time spent in chewing and rumination increased with the addition of corn silage. The replacement of corn silage by extruded roughage can be performed in up to 80% without causing any deleterious effects to adult sheep.
... In this study, it was observed that with a high THI, the animals reduced the time devoted to eating as well as the rumination time. This might be considered as a behavioral adaptation to heat stress since forage digestion leads to a large amount of metabolic heat production, which causes an increase in body temperature [42,43]. Thus, when environmental temperatures rise and reduce the ability of heat to dissipate, in order to keep the thermal balance, cows decrease their feed intake as a strategy to alleviate heat stress [17]. ...
Heat stress plays a role in livestock production in warm climates. Heat stress conditions impair animal welfare and compromise the productive and reproductive performance of dairy cattle. Under heat stress conditions, dairy cattle modify their behavior. Thus, the assessment of behavior alterations can be an indicator of environmental or physiological anomalies. Moreover, precision livestock farming allows for the individual and constant monitoring of animal behavior, arising as a tool to assess animal welfare. The purpose of this study was to evaluate the effect of heat stress on the behavior of dairy cows using activity sensors. The study was carried out in Tinajeros (Albacete, Spain) during the summer of 2020. Activity sensors were installed in 40 cows registering 6 different behaviors. Environmental conditions (temperature and humidity) were also monitored. Hourly data was calculated for both animal behavior and environmental conditions. Temperature and Heat Index (THI) was calculated for each hour. The accumulated THI during the previous 24 h period was determined for each hour, and the hours were statistically classified in quartiles according to the accumulated THI. Two groups were defined as Q4 for no stress and Q1 for heat stress. The results showed that animal behavior was altered under heat stress conditions. Increasing THI produces an increase in general activity, changes in feeding patterns and a decrease in rumination and resting behaviors, which is detrimental to animal welfare. Daily behavioral patterns were also affected. Under heat stress conditions, a reduction in resting behavior during the warmest hours and in rumination during the night was observed. In conclusion, heat stress affected all behaviors recorded as well as the daily patterns of the cows. Precision livestock farming sensors and the modelling of daily patterns were useful tools for monitoring animal behavior and detecting changes due to heat stress.
... The adverse effects of heat stress caused by high ambient temperature (AT) on dairy production are the greatest in summer (Bouraoui et al. 2002), and the effects of heat stress is intensifying and lasting longer because of global warming (Ammer et al. 2018). Many studies have investigated the relationship of ambient factors, such as temperature and humidity, and production, with the adverse effects of heat stress. ...
Context Heat stress has led to a serious reduction in dairy cows production performance, thus increasing the stress of feeding and reproduction management. Aims Heat stress arises when cows are unable to dissipate excess body heat, we aimed to investigate the effects of ambient temperature (AT) and humidity on diurnal body temperature and activity. Methods For improving the technology for rearing dairy cows, the vaginal temperature (VT) and activity of 60 Holstein heifers in summer (n = 20), autumn (n = 20), and winter (n = 20) were measured using the oestrus monitoring system. Key results We found that VT fluctuated slightly (~38.22–38.32°C) when AT and temperature-humidity index (THI) were lower than 20°C and 68, respectively. However, when this threshold is reached, VT increased significantly with increasing AT and THI, whereas activity decreased significantly. Conclusions Heat stress may be caused when THI is above 68 and cow’s VT reaches 38.32°C. Evidently, when the THI exceeds 68 and VT is more than 38.32°C, suitable measures for reducing the effect of heat stress on the productivity of dairy cows should be taken. Implications The combined monitoring of VT and THI might provide accurate guidance for preventing and controlling heat stress.
... While there have been many studies on the relationship between THI and DMI in cattle (e.g. Ammer et al. 2018;Allen et al. 2015;Bouraoui et al. 2002;Holter et al. 1997;Holter et al. 1996;Rodriquez et al., 1985), such studies have often been conducted under site-specific conditions. This diversity of experimental treatments as well as a lack of standardisation of feed and heat stress metrics makes comparisons of results, metrics and general principles across studies difficult. ...
Changes in frequency and severity of heat waves due to climate change pose a considerable challenge to livestock production systems. Although it is well known that heat stress reduces feed intake in cattle, effects of heat stress vary between animal genotypes and climatic conditions and are context specific. To derive a generic global prediction that accounts for the effects of heat stress across genotypes, management and environments, we conducted a systematic literature review and a meta-analysis to assess the relationship between dry matter intake ( DMI ) and the temperature-humidity index ( THI ), two reliable variables for the measurement of feed intake and heat stress in cattle, respectively. We analysed this relationship accounting for covariation in countries, breeds, lactation stage and parity, as well as the efficacy of various physical cooling interventions. Our findings show a significant negative correlation ( r = − 0.82) between THI and DMI , with DMI reduced by 0.45 kg/day for every unit increase in THI . Although differences in the DMI - THI relationship between lactating and non-lactating cows were not significant, effects of THI on DMI varied between lactation stages. Physical cooling interventions (e.g. provision of animal shade or shelter) significantly alleviated heat stress and became increasingly important after THI 68, suggesting that this THI value could be viewed as a threshold for which cooling should be provided. Passive cooling (shading) was more effective at alleviating heat stress compared with active cooling interventions (sprinklers). Our results provide a high-level global equation for THI-DMI across studies, allowing next-users to predict effects of heat stress across environments and animal genotypes.
... In regions where heat stress is prevalent, dairy cows experience a severe reduction in energy available for reproduction. One reason is because cows continue milking even when their maintenance expenditures are considerably higher (due to the thermoregulatory responses) than those required in thermoneutral conditions (West 2003), and another reason is because dairy cows under heat stress reduce dry matter intake (DMI) as a major adaptation in order to minimize metabolic heat production (Ammer et al. 2017). Endocrine axes of PRL and GH/IGF-1, along with their respective regulators, appeared to orchestrate, at least in part, the reproductive performance of heat-stressed cattle (Alamer 2011). ...
Reproductive management in lactating Holstein cattle is a challenge for dairy producers in Northwestern Mexico where a semi-desert, yet humid, environment is predominant. Under such conditions, a superior cow's ability to get pregnant early during postpartum is desirable to reduce the number of days open and improve fertility parameters. The objective of this study was to predict days open (DO) and pregnancy rate (PR) in lactating Holstein cows using molecular markers associated with fertility in Holstein cows managed in a warm climate. This study included 510 cows from three dairy herds located in the Yaqui Valley of Sonora. A blood sample was collected from every cow and spotted onto FTA cards. Each cow was genotyped for 179 tag SNP within 43 genes in the prolactin and GH-IGF1 pathways. An association mixed-effects model identified three SNP within the genes AVPR1A, PRLR and SSTR2 associated with DO (P < 0.05), and five SNP within the genes IGFBP2, IGFBP5, PRLR, PIAS1 and SSTR2 associated with PR (P < 0.05). The SNP effects were estimated and used to calculate the individual molecular breeding values (MBV) for DO and PR. Average MBV were 20.91 ± 0.21 d and 0.29 ± 0.003% for DO and PR, respectively. The correlation between the MBV and DO was 0.0008 (P = 0.968), whereas correlation between MBV and the estimated breeding value (EBV) for DO was -0.16 (P < 0.001) with an adjusted coefficient of determination (R²) of 2.5%. For PR, its correlation with the MBV was 0.15 (P < 0.001) with a R² of 2.2%, whereas the correlation between MBV and the EBV for PR was 0.31 (P < 0.001) with a R² of 9.6%. Heritability estimates were 0.06 ± 0.11 and 0.04 ± 0.06 for DO and PR, respectively. In conclusion, candidate gene SNPs from the prolactin and GH-IGF1 pathways were effectively used to construct an MBV for fertility traits in heat-stressed Holstein cattle. These SNP explained only a small amount of variation for PR, but not for DO; therefore, additional research using denser SNP panels and a larger population is suggested to improve the power of the MBV as genetic predictor for fertility traits in lactating dairy cows managed under warm environmental conditions.
... Therefore, proper design of a dairy shelter is important to ensure good productivity and reduce strees. As previous study mentioned that heat stress leads to a decrease in feed intake of dairy cows, thereby leading to a reduction in milk yield [16]. When the ambient temperature and relative humidity rise the animals increase body heat loss, which results in reduced metabolic rate and decreased feed consumption [14]. ...
This study aimed to evaluate the physiological responses of the Holstein Friesian (HF) dairy cows raised under tropical conditions in Indonesia. Twenty-one dry-pregnant cows, approximately 7–8 months of pregnancy, 1-3 of lactation, 500-600 kg of body weight and 3-5 of body condition score were used for that purpose. The cows were fed twice daily in the form of total mixed ration (TMR) and given add libitum amounts of drinking water. Ambient temperature, relative humidity and temperature humidity index (THI) were recorded. Physiological responses i.e. rectal temperature (RT), pulse rate (PR) and respiration rate (RR) and heat tolerance coefficient (HTC) were also recorded. Descriptive statistics such as mean and standard deviation were performed using SPSS software. The results showed that both ambient temperature and THI reached their maximum (26.5±1.520C and 77.1±2.21, respectively) at 01:00 PM and minimum (22.6±0.510C and 71.8±0.90, respectively) at 3:00 AM. Contrarily, the relative humidity was highest (88.9±1.56%) at 03:00 AM and lowest (78.8±2.49) at 01:00 AM. The physiological responses (RT, PR and RR) and HTC increased in line with the increasing ambient temperature and THI. In conclusion, all of the HF cows are exposed to mild stress due to increasing ambient temperature and relative humidity.
... (Gasteiner et al., 2015;Kim et al., 2017;Ammer et al., 2018)(1), 3h∼6h (2), 6h∼9h (3), 9h∼12h (4), 12h∼15h (5), 15h∼18h (6), 18h∼21h (7), 21h∼24h (8)으로 설정하였다. 적용되어 진 피어슨 상관계수(Pearson's product-moment correlation)는 다음과 같다. ...
Recent trends in livestock production system via ICT technology include multiple and integrated sensor technologies such as voice, pulse, number of mastication and respiration, CCTV image recognition, etc. in order to study delivery labor, injury, disease infection, estrus, rumen, and authoring, so as to better evaluate and detect major life-producing activities of livestock at early stage. Therefore, this study was conducted to estimate correlation between carcass quality traits and biometric information in ruminant stomach such as pH, rumen body temperature, and activity sensors using a residence-type bio-capsule, which is a kind of ICT technology to improve farm productivity. Ten Korean native steers were chosen at 26 months of age and the bio-capsule data were collected for five months. The steers were slaughtered to obtain carcass quality records and statistical tests were performed to find any association of the carcass traits with those of bio-capsule traits. There were positive correlations between eye muscle area, back-fat thickness, and carcass weight with rumen pH, body temperature and activity. Intramuscular fat and maturity showed positive correlations with body temperature and negative correlations with pH and activity. Conversely, texture had a negative (positive) correlation with body temperature (pH and activity). In particular, the correlation coefficient between activity and intramuscular fat was –0.65, with statistical significanse (p <0.05), suggesting that intramuscular fat increases as cow activity becomes low. The correlation coefficient between rumen pH and carcass weight was 0.50, a positive (+) correlation, suggesting that the lower the pH of the rumen, the smaller the body weight becomes. However, further study is needed to determine other factors affecting the carcass quality, or season and times on day and night to better characterize the relationships between carcass quality and bio-capsule traits in ruminant stomach, which may be helpful to improve carcass quality in Korean native steers.
... Animals fed with conventional diet had an average daily water intake of 19.7 L day − 1 and compared to 23.1 L day − 1 for animals with co-product diet. Ammer et al. (2017) observed that variation in the dry matter content of the diet, silage type, and concentrate ratio might have influenced the water intake of cattle on a feedlot. ...
Beef cattle production systems hide an enormous variability of productive and management aspects that impact the water footprint value. To have a greater precision in decision making based on water footprint we should consider animal-individuality and propose managements solutions. The aims of this study were to calculate the water footprint for a tropical cattle production system and to evaluated the influence of each individual-animal performance and type of diet. This study calculated the volumetric water footprint (WF) in its two dimensions: green and blue. The reference units were: L kg LW-1 (liters per kg of live weight) and L kg CW-1 (liters per kg of carcass weight). This study used a population of 52 Nelore bulls (Bos taurus indicus). In the feedlot phase, cattle were divided into two subgroups by weight. Each subgroup was further divided into nutritional treatment groups: Co-product Feed Light Animals (COP_L) and Heavy (COP_H) and Conventional Feed Light Animals (CON_L) and Heavy (CON_H). Co-product diet consisted of corn silage + corn germ + citrus pulp + peanut meal. Conventional diet consisted of corn silage + maize + soybean meal. The type of diet did not significant affect carcass weight and live weight (p < 0.05). The individual-animal WF varied from 32,569 L - 29,923 L kg CW-1 and from 18,279 - 16,803 L kg LW-1. The weight of animals did not significantly affect performance indicators and water footprints for conventional diet (p < 0.05), but the green and total water footprints were significantly affected for co-product diets (p < 0.05). This information could be used to support improvements in policies and good practices for farmers and policy makers to enhance the beef water efficiency. The study also contributed to produce data that are still scarce in science about the use of water along beef chain and benchmark water footprint. The generation of information about meat water footprint and practices that can make the product more water efficient will have immediate value for decision making about present and future beef meat sustainability.
... A study by Robinson et al [87] showed that heat production increases with an increase in ambient temperature, resulting in a concomitant increase in the body temperature of the cow, this leads to lower milk production [37,51]. As ambient temperature increases in the summer months, and as body temperature concomitantly increases, cows decrease their feed intake to mitigate heat stress, thereby leading to a gradual decline in milk production and a change in milk content [88]. Feed intake of dairy cows begins to decrease when the ambient temperature reaches 25°C, and sharply decreases when the ambient temperature exceeds 40°C, after which feed intake is approximately 20% to 40% lower than the normal intake, the combination of decreased feed intake and increased ambient temperature gradually result in lower milk yield [5]. ...
The thermal comfort region for greatest animals is between 4 °C and 25 °C and when environmental temperature surpasses 25°C, animals suffer from heat stress conditions. Over 50% of the cattle population is located in the tropics and it has been appraised that heat causes severe economic loss in approximately 60% of the dairy farms around the world. In tropical and subtropical countries, the climatic characteristic is the major constraint on animal productivity. In severe heat stress, growth, milk yield, milk composition and reproductive traits are reduced as a result of the extreme changes in biological functions affected by heat stress. Heat stress disturbs the steady-state concentrations of free radicals, resulting in both cellular and mitochondrial oxidative damage. Although heat stress causes a decline in dry matter intake, the cow's energy and protein requirements in hot environments increase. This review provides an overview of the impact of heat stress on farm animals.
... In response dairy cows reduce feed intake, which is directly associated with negative energy balance, which largely responsible for the decline in milk synthesis (Wheelock et al., 2010). As previously mentioned, heat stress leads to a decrease in feed intake of dairy cows (Ammer et al., 2018), thereby leading to a reduction in milk production (Ravagnolo et al., 2000;Ufuk, 2020). Reduction in feed intake not only decrease the energy supply for milk production, but maintenance requirements of energy also increased by 30% in heat stress dairy animal. ...
In livestock production system, dairy breeds are typically more sensitive to heat stress than meat breeds. Higher producing dairy animals like Holstein dairy cattle are more susceptible since they generate more metabolic heat. Heat stress negatively influences intake, rumen physiology, milk production and composition in dairy animals. Due to the rise in global warming issues, it is expected that heat stress in dairy cows will be more widespread in the future. Heat stress in dairy animals directly affect feed intake and rumen physiological functions thereby reduces milk yield and negative impact on milk composition. To address the negative impact of heat stress in dairy animals, researchers have examined various available nutritional strategies, including dietary fiber, dietary fat, dietary microbial additives, vitamins, minerals, metal ion buffer, plant extracts, and other anti-stress additives. However, two major nutrients fiber and fats are easily available macronutrients that can alleviate the negative impact of heat stress in dairy animals. This review will provide evidence for the efficacy of these nutritional strategies to mitigate the negative effects of heat stress in dairy cows. Furthermore, information on this review may provide an appropriate dietary strategy to cope with heat stress at dairy farms.
... Moreover, the metabolomic disturbances induced by HS also make the dairy cows more susceptible to diseases [19]. Severe energy reduction caused by reduced DMI is responsible for the above changes of the dairy cows under HS [20]. However, some studies suggested that HS-induced decrease in DMI accounted for only approximately 35-50% of the MY reduction [21]. ...
Background: Heat stress (HS) becomes a serious threat to dairy cow industry in certain circumstances, N-carbamylglutamate (NCG) is a novel feed additive that may be used to alleviate HS. However, the effects and mechanisms of NCG on dairy cows under HS are still unknown. A total of 48 Holstein dairy cows with similar days in milk (154.37±13.56 d), parity (1-3), and body condition score (BCS) were randomly divided into 4 groups of 12 animals each. Under HS, the cows were fed a TMR diet supplemented with 0 (control), 15, 20, 25 g of NCG/d per cow for 60 days. Milk production performance was recorded and serum parameters were examined. Meanwhile, metabolomics study of plasma based on liquid chromatography–mass spectrometry (LC-MS) was also applied to investigate metabolites and pathways in response to NCG supplementation.
Results: Milk yield (MY) was increased but milk urine nitrogen (MUN) was reduced by the NCG treatment. Addition of 15 g of NCG/d increased the milk protein percentage (MPP) compared with the control. No effect of NCG was observed on dry matter intake (DMI), lactose percentage (LP), milk fat percentage (MFP) and somatic cell count (SCC). Serum glucose (GLU) levels in cows fed with 15, 20, 25 g of NCG/d were increased by 14.35%, 19.34% and 18.63% in comparison with the control. Meanwhile, the concentrations of blood urea nitrogen (BUN) and blood ammonia (BA) were decreased with the addition of NCG. Results for antioxidant capacity and immune function showed beneficial effects of NCG, such as the increases in total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), IgG, IgM and IgA. Clear separations of plasma metabolic profiles between control and NCG groups were observed in the score plots. Sixteen different metabolites involved in metabolisms of amino acids, ketone bodies, butanoate and energy, as well as gut microbiome-derived metabolism were regulated by NCG supplementation.
Conclusions: This study found that NCG treatment improved antioxidant capacity, immune function, production performance, and metabolic profile of dairy cows under HS and provided new evidence for the better utilization of NCG.
... Heat stress is also detectable by behavioral alterations such as a reduction and/or changes in activity (Cook et al., 2007), increased water intake, reduced feed intake (Ammer et al., 2017) or a shift in feed intake to colder times of the day. Allen et al. (2015) described changes in standing and lying behavior of heat-stressed dairy cattle what might further decrease obvious estrus signals such as mounting. ...
The so-called global change refers to changes on a planetary scale. The term encompasses various issues like resource use, energy development, population growth, land use and land cover, carbon and nitrogen cycle, pollution and health, and climate change. The paper deals with challenges for dairy cattle production systems in Europe arising from climate change as one part of global changes. Global warming is increasing, and therefore ecosystems, plant and animal biodiversity, and food security and safety are at risk. It is already accepted knowledge that the direct and indirect effects of global warming in combination with an increasing frequency of weather extremes are a serious issue for livestock production, even in moderate climate zones like Central Europe. The potential and already-measurable effects of climate change (including increase in temperature, frequency of hot days and heat waves), in particular the challenges on grassland production, fodder quality, nutrition in general, cow welfare, health as well as performance of dairy production, will be reviewed. Indirect and direct effects on animals are correlated with their performance. There are clear indications that with selection for high-yielding animals the sensitivity to climate changes increases. Cumulative effects (e.g. higher temperature plus increased pathogen and their vectors loads) do strengthen these impacts. To cope with the consequences several possible adaptation and mitigation strategies must be established on different levels. This includes changes in the production systems (e.g. management, barn, feeding), breeding strategies and health management.
... Based on behaviour monitoring data, it may be stated that during hot periods, water intake increases (Ammer et al., 2018;Hanu sovský et al., 2017;Pereyra et al., 2010;Polsky & von Keyserlingk, 2017). However, the frequency of defecation and urination was often reduced (Ratnakaran et al., 2017). ...
The objective of this study was to provide a review of animal-related factors indicative of heat stress in dairy cows. To date, the temperature humidity index (THI) is a common method of evaluating the risk of heat stress in cows by employing climatic parameters. However, the THI is a general and indirect indicator that fails to consider individual cows. Various studies used animal-related parameters to account for heat load of individual cows. This review provides an overview of different heat stress indicators used over the past 10 years with a focus on animal-related and non-invasive indicators. These indicators were reviewed with regard to their potential for quantifying individual heat loads in ongoing and future studies of dairy cows. This review is divided into sections covering physiological, behavioural and performance indicators. Parameters that appear to be suitable for assessing the individual stress loads of dairy cows include respiration rate and body temperature, whereas losses in milk yield are more of a consequence of heat stress than an indicator. Using activity and feeding behaviour as an indicator of heat stress may depend on the cows’ physiological state. However, no thresholds for animal-related indicators employed as signs of heat load can be found in the literature. In contrast, thresholds for THI levels are described above which changes in cows’ physiology and behaviour are detectable under heat stress. In conclusion, the development and use of non-invasive sensors should focus on physiological indicators, and further studies are needed to determine the thresholds for these indicators.
Livestock production and human civilization are interlinked. Since the start of human civilization, livestock has been playing vital roles. Livestock serves as a source of milk and protein, an agricultural business, and a pet. Every individual requires animal proteins on a daily basis, such as meat and dairy products, the majority of which are derived from livestock animals. Industrialization of livestock production has become an important component of global GDP and a source of income for both industrialists and low-income marginal communities around the world. Production of livestock depends on intrinsic factors as well as environmental factors. Environmental factors such as temperature, humidity, rainfall, and so on have a significant impact on farm animal production, survivability, and disease load. The level of environmental stress differs in different climatic conditions. Therefore, a concrete understanding of environmental stress factors is required to ensure the optimum production of livestock. In this chapter, we discuss thermal stress and its detection methods, adaptive thermal stress management, the effects of temperature on bovine health, milk production, beef production, and reproductive performance, thermal effects on water availability, livestock diseases and intramammary infection, uses of small ruminants for livelihood, livestock sources of methane, and strategies to mitigate thermal stress and methane emissions.
This study aims to evaluate water, land, and nutrient efficiencies in a tropical beef feedlot system, considering local conditions and feed cultivation. The study was conducted at the Experimental Feedlot of Embrapa Southeast Livestock in Brazil. Forty-eight Nellore bulls were divided into two groups, with one group having shade (GS) and the other without shade (GWS). The animals' body weights, water intake, and dry matter intake were recorded. The water footprint was calculated using a product-focused assessment, considering water consumed in feed production and animal drinking. The nutrient balance and land footprint were also assessed. To both treatments, the crop scenario with soybean and corn first crop produced in Maringa resulted in the lowest water and land footprint values. Corn was the main contributor to green water consumption. The efficiency in water use for corn decreased between the first and second crops. The water footprint of soybean meal varied between production locations. GWS had slightly higher average blue water consumption than GS. In terms of nutrient balance, the GS treatment exhibited lower nitrogen and phosphorus balance values, indicating higher efficiency in the use of these elements. The provision of artificial shading was found to reduce the water footprint and improve nutrient use efficiency. The location of grain production and the timing of corn planting were identified as key factors influencing water and land footprint values.
This study presents a largely indicator-based assessment of observed and projected climate change, impacts, risks, and vulnerabilities to national economy, agriculture, energy, forestry, human health, and society, based on a wide range of observations and different GCMs simulations. It identifies the regions and Administrative-Territorial Units (ATUs) that are experiencing particularly severe climate change impacts, risks and vulnerabilities. The principal sources of uncertainty for the climate change indicators and modelling results are discussed and, where appropriate, reflected in the assessments. The climate change indicators included in this report cover observed and future time periods, and information is presented at different levels of aggregation: national, regional (Northern, Central and Southern AEZs), ATUs and districts.
The study was carried out to compare the in vitro and in vivo heat shock responses of cattle and buffaloes. The expression of heat responsive genes (HSP70 and HSF family) were studied in vitro in peripheral blood mononuclear cells (PBMCs) of cattle and buffalo. In vivo observations on animals were carried out to investigate the physiological responses of cattle and buffalo at different THI over a period of 14 months. The study indicated that onset and severity of heat stress at different THI varied significantly between cattle and buffalo. Rectal temperature (RT) showed a significant (p < 0.05) increase at THI 67 in buffaloes and at THI 68 in cattle. Significant (p < 0.01) differences in RT between the species were observed at THI 71, 72, and 73. Respiration rate (RR) significantly (p < 0.05) increased at THI 70 in both the species and significant (p < 0.05) differences in RR were observed between the species at THI 65, 68, 69, and 74. THI had significant (p < 0.05) effect on blood glucose and blood electrolytes of the species with increased levels at higher THI. Serum AST and ALT levels showed less pronounced changes over increasing THI. Heat stress-associated expressions of HSP 70 genes followed temporal changes with incremental THI. The expression of HSPA8 was consistent at lower THI whereas upregulation of HSPA1A and HSPA1L was evident at higher THI. The study concludes that changes in physiological parameters such as RT and RR occur in a phasic pattern in both species and onset of heat stress was early in buffalo as compared to cattle.
O objetivo deste trabalho foi avaliar os efeitos da casca de soja extrusada em substituição à silagem de milho. Utilizou-se vinte ovelhas da raça Santa Inês, sendo 10 animais para cada dieta, com peso médio de 57,00kg e média de três anos de idade. Os tratamentos eram compostos por volumoso extrusado e silagem de milho. Houve avaliação de consumo, digestibilidade, comportamento ingestivo e metabólitos sanguíneos. Utilizou-se delineamento inteiramente casualizado. Houve maior consumo de matéria seca (CMS) para animais alimentado com volumoso extrusado. Ocorreu diferenças estatísticas para as variáveis relacionadas a ingestão hídrica, parâmetros fecais e urinários, comportamento ingestivo, glicemia e metabolitos sanguíneos proteicos e energéticos. Os tempos gastos em mastigação e ruminação aumentaram conforme a adição de silagem de milho. Conclui-se que a substituição da silagem de milho pelo volumoso extrusado pode ser realizada sem causar quaisquer efeitos deletérios aos ovinos adultos.
Water buffalo (Bubalus bubalis) is the mainstay of milk production in Asian countries including India. However, the hot climate of the country remains the biggest bottleneck to exploit the potential of this species. Therefore, a study was conducted to assess the effect of heat ameliorative measures on microclimate, thermal comfort, and behavior of Murrah buffalo heifers during summer. Buffalo heifers (n = 24) between the age of 15 and 20 months with a mean body weight of 363.75 ± 11.27 kg were randomly grouped into four treatments based on their age and body weight. The heifers kept in the shed without any cooling served as CON (control), while the animals of group CJ were tied with a cooling jacket. The buffalo heifers of the CJF group were subjected to the cooling jacket with forced air ventilation, whereas the intermittent (10 min at 2-h intervals) sprinkling followed by forced air ventilation was practiced in group SF between 900 and 1800 h throughout the experiment. The microclimatic variables were low in the sheds of groups CJ, CJF, and SF than the CON. The physiological responses such as rectal temperature, skin temperature, respiration rate, and pulse rate were reduced in groups CJ, CJF, and SF than the CON at 1400 h. The serum cortisol was less in the CJF and SF than those of CON group. The animals of the CJ, CJF, and SF groups spent more time for feeding and rumination with less frequent longer bouts. The extended periods of lying followed by shorter standing and idling were observed in groups CJ, CJF, and SF when compared with the CON. It may be therefore concluded that cooling jacket and intermittent sprinkling in combination with forced air ventilation might be helpful in improving the micro-environment, thermal comfort, and behavior of buffalo heifers particularly under tropical climates during summer.
Visual estrus observation can only be confirmed at a rate of 50%–60%, which is lower than that obtained using a biosensor. Thus, the use of biosensors provides more opportunities for artificial insemination because it is easier to confirm estrus than by visual observation. This study determines the accuracy of estrus prediction using a ruminoreticular biosensor by analyzing ruminoreticular temperature during the estrus cycle and measuring changes in body activity. One hundred and twenty-five Hanwoo cows (64 with a ruminal biosensor in the test group and 61 without biosensors in the control group) were studied. Ruminoreticular temperatures and body activities were measured every 10 min. The first service of artificial insemination used gonadotropin-releasing hormone (GnRH)-based fixed-time artificial insemination protocol in the control and test groups. The test group received artificial insemination based on the estrus prediction made by the biosensor, and the control group received artificial insemination according to visual estrus observation. Before artificial insemination, the ruminoreticular temperature was maintained at an average of 38.95 ± 0.05°C for 13 h (−21 to −9 h), 0.73°C higher than the average temperature observed at −48 h (38.22 ± 0.06°C). The body activity, measured using an indwelling 3-axis accelerometer, averaged 1502.57 ± 27.35 for approximately 21 h from −4 to −24 h before artificial insemination, showing 203 indexes higher body activity than −48 hours (1299 ± 9.72). Therefore, using an information and communication techonology (ICT)-based biosensor is highly effective because it can reduce the reproductive cost of a farm by accurately detecting estrus and increasing the rate of estrus confirmation in cattle.
Environmental temperature is one of the major factors to affect health and productivity of dairy cattle. Gene expression networks within the cells and tissues coordinate stress response, metabolism, and milk production in dairy cattle. Epigenetic DNA methylations were found to mediate the effect of environment by regulating gene expression patterns. In the present study, we compared three Indian native zebu cattle, Bos indicus (Sahiwal, Tharparkar, and Hariana) and one crossbred Bos indicus × Bos taurus (Vrindavani) for stress gene expression and differences in the DNA methylation patterns. The results indicated acute heat shock to cultured PBMC affected their proliferation, stress gene expression, and DNA methylation. Interestingly, expressions of HSP70, HSP90, and STIP1 were found more pronounced in zebu cattle than the crossbred cattle. However, no significant changes were observed in global DNA methylation due to acute heat shock, even though variations were observed in the expression patterns of DNA methyltransferases (DNMT1, DNMT3a) and demethylases (TET1, TET2, and TET3) genes. The treatment 5-AzaC (5-azacitidine) that inhibit DNA methylation in proliferating PBMC caused significant increase in heat shock-induced HSP70 and STIP1 expression indicating that hypomethylation facilitated stress gene expression. Further targeted analysis DNA methylation in the promoter regions revealed no significant differences for HSP70, HSP90, and STIP1. However, there was a significant hypomethylation for BDNF in both zebu and crossbred cattle. Similarly, NR3C1 promoter region showed hypomethylation alone in crossbred cattle. Overall, the results indicated that tropically adapted zebu cattle had comparatively higher expression of stress genes than the crossbred cattle. Furthermore, DNA methylation may play a role in regulating expression of certain genes involved in stress response pathways.
This study provides insights into the applicability of evaporative cooling systems for livestock air conditioning (AC) for the climatic conditions of Multan (Pakistan). Usually, direct evaporative cooling systems are used in Pakistan which are inefficient and fail to achieve the required temperature and humidity levels for livestock thermal comfort. Therefore, three different types of evaporative cooling i.e., direct evaporative cooling (DEC), indirect evaporative cooling (IEC), Maisotsenko cycle evaporative cooling (MEC) systems, and desiccant dehumidification hybrid evaporative cooling (M-DAC) system, are explored for livestock air conditioning in Multan. The study aims to explore the best livestock AC option from the viewpoints of temperature gradient, temperature-humidity index (THI), and system performance. The MEC and M-DAC systems could achieve the required livestock thermal comfort. The DEC system achieved maximum effectiveness i.e., 0.9, whereas, it was 0.55 and 0.65 in case of the IEC and MEC systems. In addition, the M-DAC system achieved highest temperature gradient (i.e., 20 °C), whereas it was 10.5, 9.3, and 7.1 °C in case of the DEC, MEC, and IEC systems. The MEC and M-DAC systems achieved optimum temperature-humidity-index for livestock thermal comfort (i.e., 68–72). Thus, the study concludes the M-DAC system as an optimum system for livestock AC.
Heat stress is a serious threat to dairy cow health worldwide. N-carbamylglutamate (NCG), a novel feed additive, has been applied in dairy cow industry. However, the effects and mechanisms of NCG on dairy cows under heat stress are still unknown. A total of 48 Holstein dairy cows with similar days in milk (154 ± 13.6 d), parity (1-3), and body condition score were randomly divided into 4 groups of 12 animals each. Under heat stress, the cows were fed a TMR diet supplemented with 0 (control), 15, 20, 25 g of NCG/d per cow for 60 days. Milk production performance was recorded and serum parameters were examined. Meanwhile, metabolomics study of plasma based on liquid chromatography-mass spectrometry was also applied to investigate metabolites and pathways in response to NCG supplementation. Milk yield was increased but milk urea nitrogen was reduced by the NCG treatment. Addition of 15 g of NCG/d increased the milk protein percentage compared with the control. No effect of NCG was observed on dry matter intake, lactose percentage, milk fat percentage and somatic cell count. Serum glucose concentrations in cows fed with 15, 20, 25 g of NCG/d were 5.34 ± 0.312, 5.78 ± 0.473 and 5.54 ± 0.711 mmol/L, which were greater than those in the control (4.87 ± 0.367 mmol/L, P < 0.05). Meanwhile, the concentrations of blood urea nitrogen and blood ammonia were decreased with the addition of NCG. Results for antioxidant capacity and immune function showed beneficial effects of NCG, such as the increases in total antioxidant capacity, superoxide dismutase, glutathione peroxidase, IgG, IgM and IgA. Clear separations of plasma metabolic profiles between control and NCG groups were observed in the score plots. Sixteen different metabolites involved in metabolisms of amino acids, ketone bodies, butanoate and energy, as well as gut microbiome-derived metabolism were regulated by NCG supplementation. In conclusion, supplementation with NCG has the potential to enhance production performance, antioxidant capacity and immune function, and improved the metabolic profile of dairy cows under heat stress.
The overall objective of the current study was to evaluate the effects of 2 carriers (Silica, SIL, and Tween 80, T80) and their interaction with 8 phytochemicals (PCs), on in vitro dry matter and neutral detergent fibre digestibility (DMD, NDFD) of 3 substrates commonly used as feed for dairy cattle (soybean meal, maize meal and total mixed ration –TMR). A total of eight PCs were tested: 4 essential oils (EO) - cinnamon oil (CIN), clove oil (CLO), thyme oil (THY) and oregano oil (ORE) - and 4 essential oil active compounds (EOAC) - cinnamaldehyde (CIN-AC), eugenol (EUG), thymol (THY-AC) and carvacrol (CAR). A positive control with carrier and no PCs was tested for each substrate (CRR). Each PC was tested at 0.5 mg L⁻¹ of medium on DMD and NDFD in an in vitro batch fermentation system. The incubation was performed twice at the intervals of 4 (DMD4, NDFD4) and 24 (DMD24, NDFD24) h. The PCs effect was significant on maize meal and soybean meal DMD24. The carrier’s effect was significant on soybean meal DMD24, indicating a depressive effect of T80 on soybean meal. The PC-carrier interactions were significant on both DMD and NDFD of the tested substrates, except for maize meal and soybean meal DMD24. The PCs-SIL combinations generally increased digestibility while the combination with T80 exerted positive effect only on maize DMD4. The PC-carrier combinations variably affect digestibility of different substrates and these interactions should be considered both for their scientific and commercial implications.
• HIGHLIGHTS
• PC-Carrier interactions affect in vitro digestibility.
• In general, the PC-SIL combinations increase digestibility while those with Tween 80 exert depressing effect.
• The PC-Carrier effect is variable depending on the degraded substrate.
In addition to reduced nutrient intake, an environmental thermal load may directly affect milk yield in heat-stressed dairy cows. Feeding and lying behaviors of early lactation cows fed low fiber diets containing neutral detergent fiber (NDF) from roughage and nonforage fiber sources (NFFS) were investigated under summer conditions in Thailand. Immediately after calving, 30 multiparous cows (87.5% Holstein × 12.5% Sahiwal) were randomly allocated to dietary treatments for 63 d in a completely randomized design. The dietary treatments contained 25% of dry matter (DM) as dietary NDF. The control diet consisted of 13.9% roughage NDF from rice straw (RS). Two additional treatments were created by replacing 3.9% of DM with NDF from either soy hulls (SH) or cassava (Manihot esculenta Grantz) residues (CR), so that the roughage NDF content was reduced to 10%. During the experimental period, the minimum and maximum temperature-humidity indices (THI) were 86.4 ± 2.5 and 91.5 ± 2.7 during the day and 74.2 ± 2.1 and 81.0 ± 2.5 during the night, respectively, indicating conditions appropriate for induction of extreme heat stress. The duration of feeding and lying bouts decreased linearly with increasing THI. The DM intake during the day was greater for cows fed diets containing SH and CR than for those fed the diet containing NDF from RS. The number of meals during the day and night was lower, whereas meal size and meal length during the day and night were greater for cows fed diets containing SH and CR. Cows fed diets containing SH and CR lay down less frequently and longer during the day. These results suggest that under the severe heat stress during the day, early lactation cows fed the diet containing NFFS increased DM intake by increasing meal length and meal size rather than by increasing meal frequency and they spent more time lying. Cows fed diets containing NDF from SH and CR produced more 4% fat-corrected milk, lost less body weight, and had lower rectal temperatures measured at the 1530 h milking. Therefore, reducing the filling effect may contribute to reducing heat load derived from the change in feeding and lying behavior. This should be considered as a factor for impairing productivity of heat-stressed early lactation cows.
Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
The aim of the present study was to evaluate the impact of summer temperatures in a temperate climate on mid-lactation Holstein dairy cows. Therefore, a data set was examined comprising five trials with dairy cows conducted at the experimental station of the Friedrich-Loeffler-Institute in Braunschweig, Germany. The temperature?humidity index (THI) was calculated using temperature and humidity data from the barns recorded between January 2010 and July 2012. By using a generalised additive mixed model, the impact of increasing THI on dry matter intake, milk yield and milk composition was evaluated. Dry matter intake and milk yield decreased when THI rose above 60, whilst water intake increased in a linear manner beyond THI 30. Furthermore, milk protein and milk fat content decreased continuously with increasing THI. The present results revealed that heat stress exists in Lower Saxony, Germany. However, further research is necessary to describe the mode of action of heat stress. Especially, mild heat stress has to be investigated in more detail and appropriate heat stress thresholds for temperate climates have to be developed.
The objective of this study was to measure the effect of feeding two total mixed rations (TMRs), differing in their roughage content and in vitro dry matter digestibility, on the respiratory rate, body temperature, eating behavior and energy balance of lactating cows. The partitioning of metabolizable energy intake (MEI) between heat production (HP) and retained energy (RE) of cows held under heat load conditions was measured. Forty-two lactating cows were divided into two similar sub-groups, each of 21 animals, and were fed either a control (CON) ration containing 18% roughage neutral detergent fiber (NDF) or an experimental (EXP) TMR that contained 12% roughage NDF and used soy hulls as partial wheat silage replacer. The in vitro DM digestibility of the CON and EXP TMRs was 75.3 and 78.6%, respectively (P
The main objective of this experiment was to monitor the rumination pattern during the summer season in lactating dairy cows and to investigate its relationships with metabolic conditions and physiological markers of heat stress. The study was carried out in an experimental freestall barn located near Piacenza, Italy (45°01'N, 9°40'E; 68 m above sea level), and involved 21 Italian Friesian cows (11 primiparous and 10 multiparous) during the summer season. Rumination time (RT) was recorded by using an automatic system and data were calculated and summarized in 2-h intervals. Microclimatic conditions (temperature and relative humidity) inside the barn were recorded during the trial, and the temperature-humidity index (THI) was calculated. Breathing rates and rectal temperatures were recorded following stable meteorological periods characterized by lower and higher temperatures. At the same times, blood samples were collected to assess biochemical variables related to energy, protein, and mineral metabolism, as well as markers of inflammatory conditions and enzyme activity. Daily milk yield, body weight, nutritional condition, and health status were also recorded. The average RT was 501 min/d, with no significant differences between primiparous and multiparous cows. According to the microclimatic conditions and physiological markers of heat stress, the cows suffered mild to moderate heat stress during the summer. A negative relationship between daily maximum THI and RT was observed (r = -0.32), with a reduction of 2.2 min of RT for every daily maximum THI unit over the threshold of daily maximum THI of 76. Most of the rumination occurred during the night (on average the nighttime RT was 63.2% of daytime and nighttime RT); moreover, the proportion of nighttime RT slightly but significantly increased as THI increased. Rumination time throughout the trial was negatively related to breathing rate and positively related to milk yield. Daily maximum THI was negatively correlated with plasma glucose (r = -0.52) and positively correlated with plasma β-hydroxybutyric acid (r = 0.26). Values of plasma β-hydroxybutyric acid were positively related to RT through the trial. Our results indicate that hot conditions negatively affect RT and modify its daily pattern. The relationship between RT and the physiological markers used in our trial support the use of RT as a marker of heat stress.
Thermal stress can impact negatively on performance of intensively managed livestock in the southern United States and other subtropical and tropical regions of the world. Three funda- mental management practices, physical protection, genetic development and nutritional manage- ment schemes, have been proposed to alleviate partially the extent and severity of thermal stress. Focus of this paper is on i) interrelationships of thermal stress with functions involved in acqui- sition of nutrients and their metabolism, 2) considerations for provision of energy and nutrients during thermal stress and 3) potential practical management strategies to enhance animal pro- ductivity and efficiency. Discussion concentrates primarily on cattle. Acquisition of potentially absorbable nutrients and energy by the thermal-stressed animal is affected negatively by reduc- tion in dry matter intake, positively by slightly enhanced digestibility because of greater reten- tion time in the gut and, probably, negatively by reduced blood flow to and nutrient absorption from the alimentary tract. Negative influences of reduced intake and absorption of nutrients largely offset small enhancement in digestibility, resulting in less total nutrients being available to the thermal-stressed animal. Physiological adaptations to acute and(or) chronic thermal stress alter metabolism of absorbed energy substrates and nutrients. Hormones involved in adaptation to thermal stress include prolactin, growth hormone, thyroxine, glucocorticoids, antidiuretic hor- mone and aldosterone. These are either involved with nutrient partitioning and homeorhesis or with need for homeostatic regulation, potentiated by the thermal stressor. Increasing the energy density of diets fed to thermal-stressed animals by increasing concentrate to forage ratios or adding protected fat is discussed. For supplemental protein, the idea is suggested that increasing nutrient content may not always result in the most biologically and economically efficient production for a thermal-stressed animal. Water and macromineral needs, influenced heavily by demands to maintain homeostasis and homeothermy, are altered for lactating dairy cows. However, this may not be true for animals with lower turnover rates of these nutrients. A number of nutritional technologies are available to aid the thermal-stressed animal; others are not yet developed. Establishment of prediction equations for requirements of nutrients fed to livestock in different productive states during various intensities of thermal stress are needed. Forms of equations should describe the absolute nutrient needs (e.g., g.kg milk -1 -d -1 ) rather
The increase in the worldwide demand for dairy products, associated with global warming, will emphasize the issue of water use efficiency in dairy systems. The evaluation of environmental issues related to the management of animal dejections will also require precise biotechnical models that can predict effluent management in farms. In this study, equations were developed and evaluated for predicting the main water flows at the dairy cow level, based on parameters related to cow productive performance and diet under thermoneutral conditions. Two datasets were gathered. The first one comprised 342 individual measurements of water balance in dairy cows obtained during 18 trials at the experimental farm of Méjussaume (INRA, France). Predictive equations of water intake, urine and fecal water excretion were developed by multiple regression using a stepwise selection of regressors from a list of seven candidate parameters, which were milk yield, dry matter intake (DMI), body weight, diet dry matter content (DM), proportion of concentrate (CONC) and content of crude protein (CP) ingested with forage and concentrate (CPf and CPc, g/kg DM). The second dataset was used for external validation of the developed equations and comprised 196 water flow measurements on experimental lots obtained from 43 published papers related to water balance or digestibility measurements in dairy cows. Although DMI was the first predictor of the total water intake (TWI), with a partial r
2 of 0.51, DM was the first predictive parameter of free water intake (FWI), with a partial r
2 of 0.57, likely due to the large variability of DM in the first dataset (from 11.5 to 91.4 g/100 g). This confirmed the compensation between water drunk and ingested with diet when DM changes. The variability of urine volume was explained mainly by the CPf associated with DMI (r.s.d. 5.4 kg/day for an average flow of 24.0 kg/day) and that of fecal water was explained by the proportion of CONC in the diet and DMI. External validation showed that predictive equations excluding DMI as predictive parameters could be used for FWI, urine and fecal water predictions if cows were fed a well-known total mixed ration. It also appeared that TWI and FWI were underestimated when ambient temperature increased above 25°C and possible means of including climatic parameters in future predictive equations were proposed.
Despite many challenges faced by animal producers, including environmental problems, diseases, economic pressure, and feed availability, it is still predicted that animal production in developing countries will continue to sustain the future growth of the world's meat production. In these areas, livestock performance is generally lower than those obtained in Western Europe and North America. Although many factors can be involved, climatic factors are among the first and crucial limiting factors of the development of animal production in warm regions. In addition, global warming will further accentuate heat stress-related problems. The objective of this paper was to review the effective strategies to alleviate heat stress in the context of tropical livestock production systems. These strategies can be classified into three groups: those increasing feed intake or decreasing metabolic heat production, those enhancing heat-loss capacities, and those involving genetic selection for heat tolerance. Under heat stress, improved production should be possible through modifications of diet composition that either promotes a higher intake or compensates the low feed consumption. In addition, altering feeding management such as a change in feeding time and/or frequency, are efficient tools to avoid excessive heat load and improve survival rate, especially in poultry. Methods to enhance heat exchange between the environment and the animal and those changing the environment to prevent or limit heat stress can be used to improve performance under hot climatic conditions. Although differences in thermal tolerance exist between livestock species (ruminants > monogastrics), there are also large differences between breeds of a species and within each breed. Consequently, the opportunity may exist to improve thermal tolerance of the animals using genetic tools. However, further research is required to quantify the genetic antagonism between adaptation and production traits to evaluate the potential selection response. With the development of molecular biotechnologies, new opportunities are available to characterize gene expression and identify key cellular responses to heat stress. These new tools will enable scientists to improve the accuracy and the efficiency of selection for heat tolerance. Epigenetic regulation of gene expression and thermal imprinting of the genome could also be an efficient method to improve thermal tolerance. Such techniques (e.g. perinatal heat acclimation) are currently being experimented in chicken.
Our objective was to provide a review of factors influencing heat stress in lactating dairy cows and how it affects milk production. In warmer parts of the world, during summer months in the United States, and in other temperate regions, reduced milk production resulting from heat stress counteracts tremendous genetic progress achieved in increasing milk production. Genetic progress in milk production is closely related to increased feed intake. High feed intake results in raised metabolic heat increment. High metabolic heat increment requires effective thermoregulatory mechanisms to maintain body temperature in a thermoneutral zone and in physiological homeostasis. Cows can succumb to hyperthermia if they fail to maintain thermoneutrality. Accurate measurement of when cows enter heat stress is complicated because the responses to heat stress affect not only the energy balance, but also water, sodium, potassium and chlorine metabolism. Water, sodium, potassium and chlorine are important constituents of sweat, and sweating is a major, if not the most important, thermoregulatory mechanism used to dissipate excess body heat. Due to high metabolic heat increment, and especially in the warmer months, high-producing dairy cows may enter heat stress much earlier than their lower-producing counterparts and than currently thought, or extra heat has been accommodated by physiological adaptations. Should this be the case, then strategies to reduce heat stress must be developed to enable cows to express their full genetic potential. The thermoneutral zone, heat production and heat gain, heat dissipation mechanisms, and how the lactating cow responds to heat stress are discussed.
Beet pulp contains high amounts of pectins that can reduce the risk of rumen disorders compared to using feedstuffs high in starch. The objective was to study the effects of inclusion of ensiled pressed beet pulp in total mixed rations (TMR) for high-yielding dairy cows. Two TMR containing no or about 20% (on dry matter (DM) basis) beet pulp silage were used. The beet pulp silage mainly replaced maize silage and corn cob silage. The TMR were intentionally equal in the concentrations of energy and utilisable crude protein (CP) at the duodenum. TMR were fed to 39 and 40 dairy cows, respectively, for 118 days. The average daily milk yield was about 43 kg/day. No significant differences in milk yield and milk fat or milk protein content were detected. DM intake of cows was significantly reduced by the inclusion of beet pulp silage (23.0 v. 24.5 kg/day). However, a digestibility study, separately conducted with sheep, showed a significantly higher organic matter digestibility and metabolisable energy concentration for the TMR that contained beet pulp silage. In vitro gas production kinetics indicated that the intensity of fermentation was lower in the TMR that contained beet pulp silage. In vitro production of short-chain fatty acids, studied using a Rusitec, did not differ between the TMR. However, the inclusion of beet pulp silage in the ration caused a significant reduction in the efficiency of microbial CP synthesis in vitro. The amino acid profile of microbial protein remained unchanged. It was concluded that beet pulp silage has specific effects on ruminal fermentation that may depress feed intake of cows but improve digestibility. An inclusion of beet pulp silage of up to 20% of DM in rations for high-yielding dairy cows is possible without significant effects on milk yield and milk protein or milk fat.
Multiparous, lactating Holstein cows (n = 23; 120 +/- 30 d in milk, 690 +/- 67 kg of body weight) housed in climatic chambers were randomly assigned to 1 of 2 dietary treatments: a diet containing a novel yeast culture formulation (YC) for heat stress (n = 12, 10 g/d) or a control diet (n = 11). The trial length was 28 d and consisted of a 7-d thermal neutral period (TN; 18 degrees C, 20% humidity) followed by 21 d of heat stress (HS; cyclical daily temperatures ranging from 29.4 to 37.8 degrees C and 20% humidity). Cows were individually fed a total mixed ration consisting primarily of alfalfa hay and steam-flaked corn. During TN, the YC feeding had no effect on production variables or most body temperature indices. During HS, all body temperature indices increased and YC had no effect on rump surface temperature, respiration rate, or sweating rates. Cows fed YC had lower rectal temperatures at 1200 and 1800 h (40.29 vs. 40.02 degrees C and 40.35 vs. 40.12 +/- 0.07 degrees C, respectively) compared with control-fed cows. Cows fed both diets lost body weight (42 kg) during HS, but there were no differences between diets. Control-fed cows had increased dry matter intake (DMI) and milk yield (19.1 vs. 17.9 +/- 0.5 kg/d and 32.15 vs. 29.15 +/- 0.02 kg/d, respectively) compared with YC-fed cows, but intake and milk production were similar between diets when evaluated on a body weight basis. Heat stress progressively decreased DMI (29%) and milk yield, with milk production reaching a nadir (33%) in the third week. Heat stress decreased milk protein (7%) and lactose (5%) levels, but did not alter milk fat content. Heat-stressed cows were in calculated negative energy balance (-1.91 +/- 0.70 Mcal/d) and this was unaffected by diet. Independent of diet, HS decreased plasma glucose (11%), but neither diet nor HS altered basal nonesterified fatty acid levels. Heat stress increased plasma urea N concentrations (11.5 vs. 14.8 +/- 0.4 mg/dL). Despite YC-fed cows having slightly reduced body temperatures indices, feeding YC did not prevent the negative effects of HS.
Twelve multiparous, rumen-cannulated cows (17 DIM) were fed 25 or 35% NDF diets without or with added rumen-inert bulk as water-filled plastic containers (500 ml each) within three 4 x 4 Latin squares (21-d periods). Added bulk equaled 25% of pretrial rumen volume for each cow. Objectives were to challenge cows with rumen fill in the form of dietary NDF and inert bulk to determine whether bulk affects intake similarly for diets of different NDF content or whether changes in behavior or rumen function allow cows to adapt to higher fill. Inert bulk had no effect on DMI for cows fed 25% NDF but decreased DMI for cows fed 35% NDF (18.7 vs. 16.6 kg/d). Volume of rumen digesta plus inert bulk, 102 L, was similar for 35% NDF treatments regardless of presence or absence inert bulk. Additional NDF or inert bulk increased the number of ruminating bouts per day, chewing time per unit of DMI or NDF intake, frequency of reticular contractions during rumination, and fractional passage rate of NDF from the rumen. Although these changes may help to alleviate fill, they were insufficient to maintain intake under conditions of high fill. Intake by cows receiving high fiber diets can be limited by reticulorumen capacity. Future study is required to determine the effect of rumen fiber digestion, fiber particle size, and animal characteristics on fill-limited intake.
Physical and chemical characteristics of dietary ingredients and their interactions can have a large effect on dry matter intake (DMI) of lactating cows. Physical limitations caused by distension of the reticulo-rumen or other compartments of the gastrointestinal tract often limit DMI of high producing cows or cows fed high forage diets. Fermentation acids also limit DMI from a combination of increased osmolality in the reticulo-rumen and specific effects of propionate, although the mechanisms are not clear. The specific physical and chemical characteristics of diets that can affect DMI include fiber content, ease of hydrolysis of starch and fiber, particle size, particle fragility, silage fermentation products, concentration and characteristics of fat, and the amount and ruminal degradation of protein. Site of starch digestion affects the form of metabolic fuel absorbed, which can affect DMI because absorbed propionate appears to be more hypophagic than lactate or absorbed glucose. Dry matter intake is likely determined by integration of signals in brain satiety centers. Difficulty in measurement and extensive interactions among the variables make it challenging to account for dietary effects when predicting DMI. However, a greater understanding of the mechanisms along with evaluation of animal responses to diet changes allows diet adjustments to be made to optimize DMI as well as to optimize allocation of diet ingredients to animals. This paper discusses some of the characteristics of dietary ingredients that should be considered when formulating diets for lactating dairy cows and when allocating feeds to different groups of animals on the farm.
Lactating cows were exposed to moderate and hot, humid weather to determine the effect of increasing ambient temperature, relative humidity, or temperature-humidity index (THI) on intake, milk yield, and milk temperature. Minimum and maximum temperatures averaged 17.9 and 29.5 degrees C (cool period) and 22.5 and 34.4 degrees C (hot period), and minimum and maximum THI averaged 63.8 and 76.6 (cool period) and 72.1 and 83.6 (hot period). Environmental conditions had minor effects on intake and milk yield during the cool period. During the hot period, the THI 2 d earlier and mean air temperature 2 d earlier had the greatest impact on milk yield and DMI, respectively. Both breeds maintained milk temperature within normal ranges during the cool period, but Holstein and Jersey p.m. milk temperatures averaged 39.6 and 39.2 degrees C during the hot period. Current day mean air temperature during the hot period had the greatest impact on cow p.m. milk temperature, and minimum air temperature had the greatest influence on a.m. milk temperature. Dry matter intake and milk yield declined linearly with respective increases in air temperature or THI during the hot period and milk temperature increased linearly with increasing air temperature. Dry matter intake and milk yield both exhibited a curvilinear relationship with milk temperature. Environmental modifications should target the effects of high temperatures on cow body temperature and should modify the environment at critical times during the day when cows are stressed, including morning hours when ambient temperatures are typically cooler and cows are not assumed to be stressed.
The southeastern United States is characterized as humid subtropical and is subject to extended periods of high ambient temperature and relative humidity. Because the primary nonevaporative means of cooling for the cow (radiation, conduction, convection) become less effective with rising ambient temperature, the cow becomes increasingly reliant upon evaporative cooling in the form of sweating and panting. High relative humidity compromises evaporative cooling, so that under hot, humid conditions common to the Southeast in summer the dairy cow cannot dissipate sufficient body heat to prevent a rise in body temperature. Increasing air temperature, temperature-humidity index and rising rectal temperature above critical thresholds are related to decreased dry matter intake (DMI) and milk yield and to reduced efficiency of milk yield. Modifications including shade, barns which enhance passive ventilation, and the addition of fans and sprinklers increase body heat loss, lowering body temperature and improving DMI. New technologies including tunnel ventilation are being investigated to determine if they offer cooling advantages. Genetic selection for heat tolerance may be possible, but continued selection for greater performance in the absence of consideration for heat tolerance will result in greater susceptibility to heat stress. The nutritional needs of the cow change during heat stress, and ration reformulation to account for decreased DMI, the need to increase nutrient density, changing nutrient requirements, avoiding nutrient excesses and maintenance of normal rumen function is necessary. Maintaining cow performance in hot, humid climatic conditions in the future will likely require improved cooling capability, continued advances in nutritional formulation, and the need for genetic advancement which includes selection for heat tolerance or the identification of genetic traits which enhance heat tolerance.
The aims of this study were to determine how measures of feeding, drinking, and standing behavior change over the period around calving, to derive objective meal and drinking bout criteria for transition cows, and to describe the within-cow consistency of these behavioral measures. Fifteen transition dairy cows were monitored from 10 d before until 10 d after calving. Meal criteria were calculated for each cow in both the pre- and postcalving periods and varied among cows from 5.3 to 105.2 min. There was a tendency for the average number of meals per day to be higher after calving than before calving, but time spent eating declined from 87 to 62 min/d from the precalving to the postcalving period. Time spent drinking before calving averaged 5.5 min/d and increased gradually after calving to an average of 6.8 min/d. Total daily standing times remained reasonably similar over the transition period but were highest at around calving (14.4 h) and lowest during the precalving period (12.3 h). On the day of calving, there was a dramatic increase in the number of standing bouts (21.8 bouts) compared with the pre- and postcalving averages of 11.7 and 13.1 bouts, respectively. In summary, changes in feeding behavior may help account for the well-documented changes in feed intake during transition. Documented changes in standing behavior suggest that cow comfort may be particularly important during the time around calving.
It has long been known that season of the year has major impacts on dairy animal performance measures including growth, reproduction, and lactation. Additionally, as average production per cow has doubled, the metabolic heat output per animal has increased substantially rendering animals more susceptible to heat stress. This, in turn, has altered cooling and housing requirements for cattle. Substantial progress has been made in the last quarter-century in delineating the mechanisms by which thermal stress and photoperiod influence performance of dairy animals. Acclimation to thermal stress is now identified as a homeorhetic process under endocrine control. The process of acclimation occurs in 2 phases (acute and chronic) and involves changes in secretion rate of hormones as well as receptor populations in target tissues. The time required to complete both phases is weeks rather than days. The opportunity may exist to modify endocrine status of animals and improve their resistance to heat and cold stress. New estimates of genotype x environment interactions support use of recently available molecular and genomics tools to identify the genetic basis of heat-stress sensitivity and tolerance. Improved understanding of environmental effects on nutrient requirements has resulted in diets for dairy animals during different weather conditions. Demonstration that estrus behavior is adversely affected by heat stress has led to increased use of timed insemination schemes during the warm summer months to improve conception rates by discarding the need to detect estrus. Studies evaluating the effects of heat stress on embryonic survival support use of cooling during the immediate postbreeding period and use of embryo transfer to improve pregnancy rates. Successful cooling strategies for lactating dairy cows are based on maximizing available routes of heat exchange, convection, conduction, radiation, and evaporation. Areas in dairy operations in which cooling systems have been used to enhance cow comfort, improve milk production, reproductive efficiency, and profit include both housing and milking facilities. Currently, air movement (fans), wetting (soaking) the cow's body surface, high pressure mist (evaporation) to cool the air in the cows' environment, and facilities designed to minimize the transfer of solar radiation are used for heat abatement. Finally, improved understanding of photoperiod effects on cattle has allowed producers to maximize beneficial effects of photoperiod length while minimizing negative effects.
Two experiments were conducted to investigate the physiological responses of Bos taurus (Angus cross, n = 6) and Bos indicus (Brahman, n = 6) cattle to prolonged heat and humidity, as can occur during live export by sea. Each experiment was carried out in climate-controlled rooms, where heifers were exposed to 15 d of sustained heat and humidity. The treatment was designed to be representative of a long-haul, live-export voyage leaving a southern Australian winter and traveling to a Middle Eastern summer. Wet bulb temperature (WBT) was used to give a combined measure of dry bulb temperature and relative humidity and was increased over several days, culminating in 5 d at 32 degrees C WBT between d 7 and 11. By d 11, the respiratory rate and core body temperature increased (P < 0.001) compared with values at lower ambient temperature on d 1 and 2 when climate-controlled rooms were not operating. Feed intake of Bos taurus was reduced (P < 0.001) by d 11, whereas that of Bos indicus did not change (P = 0.14). Despite no diurnal variation in climatic conditions, core body temperature of both Bos taurus and Bos indicus continued to show a circadian amplitude of approximately 1 degrees C throughout the hottest period. This amplitude increased during the recovery period after heat was removed (up to 1.8 degrees C for Bos indicus and 1.6 degrees C for Bos taurus). Water intake for both Bos taurus and Bos indicus increased when WBT increased (P < 0.01 on d 11). Significant acid-base and blood electrolyte imbalances occurred in both Bos taurus and Bos indicus, with changes in Bos taurus being more substantial and prolonged. The increase in respiratory rate coincided with a decrease in the partial pressures of carbon dioxide and bicarbonate in venous blood. However, during the hottest period, average daily venous blood pH remained unchanged. When the heat load was reduced after d 11, the blood pH decreased, indicating metabolic acidosis. Blood pH declined from 7.44 to 7.36 for Bos taurus (P < 0.001) and from 7.44 to 7.38 for Bos indicus (P < 0.001). Other parameters measured include heart rate; packed cell volume; plasma and urine Na, K, and Cl; urine pH; and specific gravity. Our results suggest that Bos taurus cattle experience significant physiological changes during exposure to prolonged and continuous high heat and humidity, with alterations persisting for some days after the heat-stress conditions subside. Bos indicus experience similar but less pronounced physiological changes.
A feeding trial was carried out with 48 dairy cows in second or later lactation. The experiment started immediately after parturition and lasted for 13 weeks. Basal diets consisted of a mixture of artificially dried grass and maize silage as roughage components and concentrates based on a mixture of by-product feeds. Additional to the basal diet, dried beet pulp, ensiled pressed beet pulp or maize silage was fed. Digestibility of the ration components was determined with in vitro and in vivo methods. The feeding value of both types of beet pulp and maize silages agreed with that reported in literature. The calculated energy balance agreed with liveweight changes. -from Authors
The objective of this study was to compare the effect of the temperature-humidity index (THI) on milk production traits and somatic cell score (SCS) of dairy cows raised in 4 different housing systems: (1) warm loose housing with access to grazing (WG), (2) warm loose housing without access to grazing (WI), (3) cold loose housing with access to grazing (CG), and (4) cold loose housing without access to grazing (CI). For each of the 4 housing systems, 5 farms with a herd size of 70 to 200 lactating cows in Lower Saxony, Germany, were studied. Ambient temperature and relative humidity were recorded hourly in each barn to calculate THI. Milk production data included 21,546 test-day records for milk, fat, and protein yield, and SCS. These data were associated with the average THI of the 3 d preceding the respective measurement, which was divided into 6 classes (<45, ≥45 to <50, ≥50 to <55, ≥55 to <60, ≥60 to <65, and ≥65). Furthermore, bulk milk samples including the fat and protein percentage, and SCS taken 4 to 6 times per month were associated with the average and maximum THI of the 3 d before sampling. Data were recorded from April 2010 to March 2011. In each of the housing systems, monthly THI values above 60, indicating heat stress, were recorded between June and September, with higher values in WI and WG. In all systems, fat-corrected milk, fat, and protein yields of the test-day records decreased in tendency from 60 ≤ THI < 65 to THI >65. In WI and CI, values for SCS were greater in the class THI >65 than in 60 ≤ THI < 65, whereas no difference between any of the THI classes was found in WG and CG. The fat and protein percentage of the bulk milk samples decreased with increasing 3-d maximum THI in all 4 systems, whereas the SCS increased with increasing 3-d average THI. In conclusion, negative effects of heat stress conditions under a temperate climate on milk production traits and SCS were found, although a housing system being superior to the other systems in altering heat stress effects was not identified.
The individual daily water intake of dairy cows has been measured under varying conditions. Two experiments with 60 Holstein cows each were conducted. The consumption of water per day by cows ranged from 14 to 171 kg/cow, with a mean of 82 kg/cow. Applying a multiple regression analysis to the data leads to the following equation: water intake (kg/day)=−26.12+1.516∗average ambient temperature (°C)+1.299∗milk production (kg/day)+0.058∗body weight (kg)+0.406∗Na intake (g/day). The coefficient of multiple determination (r2) was 0.60.
The aim of this study was to determine whether increasing a
lipogenic nutrient (beet pulp; BP) at the expense of a gluco-
genic nutrient (barley grain; BG) can decrease the body condition
score (BCS) of fat cows in late lactation. Eighteen lactating Hol-
stein cows were used in a randomized complete block design. The
cows were 171 ± 16.3 days in pregnancy, 289 ± 35.1 days in milk
and 4.12 ± 0.351 BCS at the beginning of the study. Cows were
assigned randomly to one of three dietary treatments containing:
(1) 234.7 g/kg BG (without BP), (2) 148.7 g/kg BG (86 g/kg BP), or (3)
62.7 g/kg BG (172 g/kg BP). By adding BP, the starch (190.2, 151.0,
and 123.3 g/kg DM) and NDFom (308.6, 319.3, and 337.9 g/kg DM)
levels in the TMR changed. Substituting BG by BP didn’t affect yield
of milk protein and lactose, but milk fat level and milk energy out-
put increased as BP replaced BG. Adding BP caused BCS and back fat
thickness to reduce. Plasma glucose and cholesterol decreased as BP
substituted for BG. Results suggest that inclusion of BP in diets of
fat cows during late lactation may slightly reduce BCS, and increase
milk fat and energy levels, with no effect on milk yield.
Sugar beet pulp is a by-product from the sugar refining industry. Quantities of about 500 000 tonnes of dry matter are available annually for feeding in the UK. The majority is marketed as dried molassed beet pulp (DMBP) with smaller quantities sold as pressed pulp, triple nuts and magnesium nuts.DMBP is a useful ruminant feed containing 12.5 MJ metabolisable energy and 79 g digestible crude protein/kg DM. Crude fibre content is high but of good digestibility. Rations containing a high proportion of DMBP have less of a depressive effect on roughage digestibility than high cereal rations, and acidosis is not a problem. For dairy cows the highly digestible crude fibre has beneficial effects on milk fat. Water soluble carbohydrate content is high so sugar beet pulp products tend to increase total dry matter intake. This readily fermentable carbohydrate aids good utilisation of urea when incorporated into nuts. With added minerals and urea, DMBP is marketed as triple nuts. The inclusion of unpalatable minerals such as magnesium oxide provides an easy way of giving minerals. Magnesium nuts are particularly useful for ensuring adequate magnesium intake of animals grazing spring grass.Owing to the high crude fibre content, sugar beet pulp products are not well suited to pigs and poultry.
The objective of this experiment was to evaluate the effect of feeding total mixed rations (TMR) that differ in structural and nonstructural carbohydrates to dairy cows in early and late lactation on short-term feed intake, dry matter intake (DMI), rumen fermentation variables, and milk yield. A 5 x 5 Latin square experiment with 15 dairy cows was repeated during early and late lactation. The 5 treatments were a TMR with (all on dry matter basis) 55% roughage (a 50:50 mixture of corn silage and grass silage) and 45% concentrate (a 50:50 mixture of concentrate rich in structural carbohydrates and concentrate rich in nonstructural carbohydrates; treatment CON), a TMR with the concentrate mixture and 55% grass silage (RGS) or 55% corn silage (RCS), and a TMR with the roughage mixture and 45% of the concentrate rich in structural carbohydrates (CSC) or the concentrate rich in nonstructural carbohydrates (CNS). Meal criteria, determined using the Gaussian-Gaussian-Weibull method per animal per treatment, showed an interaction between lactation stage and treatment. Feed intake behavior variables were therefore calculated with meal criteria per treatment-lactation stage combination. Differences in feed intake behavior were more pronounced between treatments differing in roughage composition than between treatments differing in concentrate composition, probably related to larger differences in chemical composition and particle size between corn silage and grass silage than between the 2 concentrates. The number of meals was similar between treatments, but eating time was greater in RGS (227 min/d) and lesser in RCS (177 min/d) than the other treatments. Intake rate increased when the amount of grass silage decreased, whereas meal duration decreased simultaneously. These effects were in line with a decreased DMI of the RGS diet vs. the other treatments, probably related to the high neutral detergent fiber (NDF) content. However, this effect was not found in CSC, although NDF content of the TMR, fractional clearance rate of NDF, and fractional degradation rate of NDF was similar between CSC and RGS. Rumen fluid pH was lesser, and molar proportions of acetic acid and of propionic acid were lesser and greater, respectively, in RCS compared with all other diets. Milk production did not differ between treatments. There was no effect of type of concentrate on milk composition, but diet RCS resulted in a lesser milk fat content and greater milk protein content than diet RGS. Lactation stage did affect short-term feed intake behavior and DMI, although different grass silages were fed during early and late lactation. The results indicate that short-term feed intake behavior is related to DMI and therefore may be a helpful tool in optimizing DMI and milk production in high-production dairy cows.
This study investigates whether dry matter (DM) or water intake is affected by the presence of disease or estrus in dairy cows and whether water intake can serve as an accurate substitute for monitoring changes in DM intake (DMI). A combined cumulative sum (CUSUM) and Shewhart monitoring scheme is proposed to detect DMI changes and emerging disease or estrus. Daily readings from 35 inline water meters for 35 water cups in a tie-stall barn at the University of Minnesota were collected from September 2005 until June 2006. Two cows were assigned to each water cup. Individual DMI were recorded for each of the 70 cows on the study. All drug or hoof treatments administered to the cows along with breeding and calving events were also recorded and classified as 1 of the following 6 event categories: estrus, calving, mastitis, fever, hoof treatment, and other. Analysis of covariance was used to identify factors significantly changing intake. Only the first 150 d in milk (DIM) were considered in the analysis. Six event categories plus DIM, ambient temperature, relative humidity, and parity were entered as independents into the model. Calving, primiparity, and health events categorized as "other" were associated with decreased DM and water intake. Mastitis decreased DMI and fever negatively affected water intake. Both intakes increased with DIM, and water intake decreased with increase in humidity. Covariance analysis was used to investigate the relationship between DMI and water intake. In model 1, analysis was done for a pair of cows, whereas model 2 modeled DMI of the whole group of 70 cows. Water intake, ambient temperature, humidity, and DIM were entered as independents in both models and parity was entered in model 1. Polynomial models and 2-way interactions were also considered. Water intake, ambient temperature, DIM, and DIM(2) were kept in final models 1 and 2, and parity was kept in model 1. Final models for cow pairs and a group of 70 cows resulted in R(2) of 0.50 and 0.82, respectively. The proposed CUSUM-Shewhart DMI monitoring scheme successfully detected emerging disease even in the first week of lactation. Monitoring water intake can serve as an alternative to measurements of DMI for groups of cows and has the potential of predicting change in individual cow health and estrus status.
Lactating dairy cows metabolize large amounts of water and are affected rapidly by water deprivation. Total body water, half-life of body water, size of component pools, and exchanges among them have been quantitated in several studies. The data underscore the dynamic nature of water metabolism in lactating cows. Water is lost in milk, urine, feces, and various forms of evaporation. Sources of water include drinking, feed, and metabolic (oxidation) water. Factors that have been shown to influence drinking behavior include eating pattern, water temperature, whether water is given in a trough or water bowl, flow rates into water bowls, animal dominance if water bowls are shared, and stray voltage. Important environmental factors modulating water consumption of dairy cattle are DMI, nature of the diet, milk production, temperature, and humidity. Equations have been proposed to predict water consumption based on measures of some of these variables. Water is of paramount importance both physiologically and nutritionally; therefore, it is not surprising that its metabolism indirectly may affect many feeding and management decisions. Ample water of acceptable quality must be provided to maximize milk production.
Twelve lactating Holstein cows in 2nd lactation were allocated randomly, six each, to two feeding treatments: high concentrate (1 kg dairy concentrate to 2 kg milk produced) and low concentrate (1 kg dairy concentrate to 4 kg milk produced) from 7 to 106 days postcalving. Forage and water were provided ad libitum. Milk and butter fat yields and rectal temperatures were examined in relation to 9 weather variables (minimum, maximum and mean temperatures, relative humidity, temperature-humidity index (THI), radiation, wind velocity and mean temperature of the previous day). Averages for milk yield, fat yield and rectal temperature were respectively 20.4 kg, 0.7 kg and 38.9 degrees C for the high concentrate treatment and 18.4 kg, 0.6 kg and 38.6 degrees C for the low concentrate treatment. Whether conditions accounted for 5.6%, 0.8% and 10.8% of the day to day variation in milk yield, fat yield and rectal temperature, respectively, for the high concentrate group and 29.4%, 9.7% and 0.6%, respectively, for the low concentrate group. Only measures of ambient temperature, especially mean temperature, were closely associated with these traits.