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Interactions Between Body Condition at Calving and Cooling of Dairy Cows During Lactation in Summer
Abstract
This study examined the interactions between dietary manipulation for increased body condition during the last trimester of pregnancy (spring) and postpartum cooling (summer lactation). Effects of diet on milk production of Holstein cows were examined to determine whether body stores could compensate for reduced DMI during heat stress. Cows calving between May and July with high (3.8 on a six-point scale) or low (2.7) body condition scores were assigned postpartum to be cooled by sprinkling and ventilation or to serve as uncooled controls. Cooled cows ate 1.6 kg more DM/d and consumed 9 L less of water/d than uncooled cows. Cooled cows maintained body temperatures below 38.9 degrees C during day hours; peak body temperature for uncooled cows was 39.7 degrees C. For 8 wk postpartum, glucose and insulin concentrations in plasma were unaltered by cooling or body condition. The NEFA were lower, and urea was slightly higher, for cows with low body condition. Milk production increased 1.9 kg/d with cooling, fat production increased with both body condition and cooling, and protein production increased with cooling but not with body condition. Performance was lowest for the uncooled subgroup with low body condition. Among cooled cows, no advantage was attributable to high body condition. An additive effect of high body condition and cooling on milk production in summer was not evident.
... Taking into account that at the time of day these physiological variables were measured (1430), the cooling equipment had been active for 4 h 30 min, estrés calórico moderado, mientras que las vacas sometidas al sistema de enfriamiento presentaron promedios de TAR (77.5 resp/min) y TER (39.1°C ), ligeramente menores que el grupo testigo. Considerando que al momento de la medición de estas variables fisiológicas por la tarde (1430) el sistema de enfriamiento había operado ya por 4 h 30 min, y a que a esta hora del día las condiciones climáticas fueron muy cercanas a su pico máximo del día (1530), estos resultados sugieren que el sistema de enfriamiento utilizado fue efectivo en relación a la reducción del estrés por calor en comparación con las vacas sin este sistema (1,27) . ...
... Un estudio señala que el efecto combinado de bajas reservas corporales y un bajo consumo de alimento en condiciones de estrés calórico fue evidente cuando vacas presentaron CC al parto menor a 2.5 (27) . A pesar de estos resultados se ha sugerido que la CC ideal para una vaca durante su periodo seco es de 3.75 (15) , lo que indica que las vacas del presente estudio iniciaron su periodo seco con una CC ligeramente elevada. ...
... En un experimento donde se relacionó época del año con hormonas tiroideas, los valores de T 4 variaron en un rango de 48.6 y 39.7 ng/ml para invierno y verano respectivamente, mientras que las concentraciones de T 3 se localizaron en un rango de 1.04 y 0.79 ng/ml para invierno y verano, respectivamente, los cuales coinciden con los encontrados en el presente estudio (30) . Se ha observado que las concentraciones de hormonas tiroideas en vacas lecheras varían inversamente con la temperatura ambiental, ya que vacas secas and that at that hour the climate conditions are near to its higher point (1530), results obtained in this study suggest that the cooling system used was helpful to reduce heat stress (1,27) . ...
In order to determine some physiological responses 60 d prepartum and production responses postpartum to a cooling system in summer, 24 multiparous Holstein cows were allocated to two groups: one group with (n=12) and a second group without (n=12) cooling. Cooled cows showed a lower (P<0.05) respiration rate (77.5 vs 83.7 breaths/min) and rectal temperature (39.1 vs 39.3 degrees C) in the afternoon, than non-cooled (control) cows. Serum thyroxin and triiodothyronine levels were higher (P<0.05) in cooled cows than in non-cooled cows (38.0 vs 30.2 ng/ml and 0.857 vs 0.681 ng/ml, respectively). Calf birth weight showed only a numerical trend to be higher (P=0.421) in cooled cows (35.7 vs 32.9). Milk production showed a tendency (P=0.144) to be higher in the cooled (28.1 kg) than in the non-cooled group (25.2 kg), while fat content (P<0.05) was greater in the cooled (3.2%) than in the non-cooled group (2.9%); therefore, average fat-corrected milk production at week eight postpartum was higher (P<0.01) for the cooled group (28.6 vs 25.7 kg) compared to control. However, milk production and protein percent were similar (P>0.05). Reproductively, only total conception rate was higher (P<0.05) in cooled cows than in non-cooled cows (100 vs 63.6%). Non-cooled cows showed a 42% culling rate, while no cow was culled in the cooled group (P<0.05). An economic analysis showed a net profit of 75 dollars cow/year for the cooling system. Results show that cooling dry cows reduce heat stress, that resulted in higher fat-corrected milk and milk fat production in the subsequent lactation and in higher economical benefits for dairy producers.
... The impact of BCS on subsequent health condition, dairy production and fertility had been evaluated by many researchers who recorded that low BCS suppressed peak milk yield and milk production traits in dairy herds, but cows with high BCS had no advantage in milk production (Flamenbaum et al., 1995). While Bayram et al. (2012) reported that milk yield, corrected 305 milk yield (305MY) and daily milk yield (DMY) of cows with low BCS at calving were significantly higher than those with moderate BCS. ...
... Moreover, the advantage of the high BCS group under the KKC system over the FC one for TMY, peak milk yield, and period, is in disagreement with Flamenbaum et al. (1995), who recorded no differences (P>0.05) among cooled cows having high BCS. ...
... among cooled cows having high BCS. Furthermore, the absence of positive interaction of KKC cooling system and BCS for peak period and yield disagrees with Flamenbaum et al. (1995), who indicated significant higher peak production due to heat stress relief (cooling) by BCS level. ...
Under tropical environments cow’s body condition at calving may influence productivity and health performance. Therefore, the current research evaluated the impact of body condition score (BCS) at calving on milk production traits and health problems of primiparous and multiparous cows raised under two cooling systems in semi-arid environment. Milk yield parameters and health disorders data at different parities were obtained from 1700 Holstein cows, which were managed under Korral Kool (KKC) and fan (FC) cooling systems in Saudi Arabia. The results revealed that KKC system induced high level of milk production improvement (305TM, days in milk, daily milk yield) (P<0.05) compared to FC, especially in multiparous cows. There was an advantage of the high BCS group under KKC system over the FC system for peak yield and period. Cows from both cooling systems having moderate BCS outdid the other groups for total milk yield. Low BCS primiparous cows reared under KKC system were the most to suffer from stillbirth (18%), and calving ease (26.1%) in winter, while high BCS were the most to be treated for mastitis (8.5% in summer). On the other hand, spring calved multiparous cows raised under FC system suffered more from lameness (21.57% - high BCS) and milk fever (4.4% - moderate BCS). Further, cows having moderate BCS kept under KKC system had the highest incidence of lameness (62.2%), and abomasum displacement (4.4%). In conclusion, achieving correct BCS at calving and cooling system is important to avoid calving subsequent lactation performance and metabolic disease losses.
... These results go in barrel with the findings of Pryce and Lovendahl (1999), , and Grummer et al. (2004), as they concluded that medium and high BCS of dairy cattle attained high milk yield [1,3,4 ]. In contrast, Boisclair (1986) and Flamenbaum et al. (1995) proved that there was no significant difference among different dairy cattle condition scores on dairy performance parameters [12][13][14]. Dairy cattle BCS possessed no significant difference in days to peak values, while it significantly differed in initial milk, peak milk yield as well as LP values. ...
... These results go in barrel with the findings of Pryce and Lovendahl (1999), , and Grummer et al. (2004), as they concluded that medium and high BCS of dairy cattle attained high milk yield [1,3,4 ]. In contrast, Boisclair (1986) and Flamenbaum et al. (1995) proved that there was no significant difference among different dairy cattle condition scores on dairy performance parameters [12][13][14]. Dairy cattle BCS possessed no significant difference in days to peak values, while it significantly differed in initial milk, peak milk yield as well as LP values. As, medium condition score cows produced significantly more initial and peak milk values (27.96± 0.12 and 35.32± 0.16 kg, respectively) as much as over condition score cows (27.69± 0.11 and 37.20± 0.18 kg, respectively) and it produced more initial and peak milk than low condition score cows (20.40± 0.18 and 25.90± 0.13 kg, respectively) at (p<0.05). ...
The present study was conducted to detect the effect of prepartum body condition score (BCS) on dairy cattle performance. Throughout the study, a total of 7956 dairy records were collected from six Holstein Friesian farms. According to the prepartum BCS, dairy cows were grouped into three main categories-low, medium, and over condition score cows for BCS values of 2-3, 3-4 and 4-5, respectively. Dairy cattles with BCS values under the level of 2 were culled as a part of culling policy in these farms. Productive parameters of milk yield (daily yield, 305-day yield and total yield), milk curve (days to peak, initial milk yield, peak milk yield and lactation persistency [LP]), milk somatic cell count (SCC) and somatic cell score (SCS), as well as some reproductive parameters (days to first estrus and days open) were determined to indicate the best dairy cattle prepartum BCS sustained high dairy performance. Prevalence of lameness and metabolic diseases (milk fever, abomasum displacement [DA] and ketosis) were also investigated in dairy cattle among different prepartum BCS. The best prepartum BCS was elucidated to reduce the prevalence of such diseases. Results of the present study revealed that the medium condition score cows produce more milk as compared to the over condition score cows. Medium condition score cows showed improved udder health and reproductive parameters. On the other hand, they showed decreased prevalence of lameness, milk fever, DA and ketosis. In contrast, it was obvious that over condition score cows suffered more from these metabolic disorders than low and medium BCS cows. The prevalence of lameness was more evident in low than in medium and over condition score cows.
... Essentially, there are five key areas on the body re-gions of cows that need to be assessed for BCS namely, the area between the tail head and pin bones, inside of the pin bones, backbone, hips and curvature between the hips and pin bones. There are different scoring scales, but the most common system in use for dairy cows in the US uses a scale of 1 to 5 with 1 being emaciated, 2 thin, 3 average, 4 fat and 5 obese (Wildman et al. 1982;Flamenbaum et al. 1995). It is common to divide the scale into 0.25 point increments (Ferguson et al. 1994;Wildman et al. 1982;Edmonson et al. 1989). ...
... Additionally, energy store may vary up to 40% in cows with similar bodyweight (Andrew et al. 1994). Therefore, body condition scoring has received considerable attention as a means to estimate tissue mobilization (Domecq et al. 1997;Flamenbaum et al. 1995). The inter-calving profile of BCS is a mirror image of the milk lactation profile (Roche et al. 2009). ...
... These results go in barrel with the findings of Pryce and Lovendahl (1999), , and Grummer et al. (2004), as they concluded that medium and high BCS of dairy cattle attained high milk yield [1,3,4 ]. In contrast, Boisclair (1986) and Flamenbaum et al. (1995) proved that there was no significant difference among different dairy cattle condition scores on dairy performance parameters [12][13][14]. Dairy cattle BCS possessed no significant difference in days to peak values, while it significantly differed in initial milk, peak milk yield as well as LP values. ...
... These results go in barrel with the findings of Pryce and Lovendahl (1999), , and Grummer et al. (2004), as they concluded that medium and high BCS of dairy cattle attained high milk yield [1,3,4 ]. In contrast, Boisclair (1986) and Flamenbaum et al. (1995) proved that there was no significant difference among different dairy cattle condition scores on dairy performance parameters [12][13][14]. Dairy cattle BCS possessed no significant difference in days to peak values, while it significantly differed in initial milk, peak milk yield as well as LP values. As, medium condition score cows produced significantly more initial and peak milk values (27.96± 0.12 and 35.32± 0.16 kg, respectively) as much as over condition score cows (27.69± 0.11 and 37.20± 0.18 kg, respectively) and it produced more initial and peak milk than low condition score cows (20.40± 0.18 and 25.90± 0.13 kg, respectively) at (p<0.05). ...
The present study was conducted to detect the effect of prepartum body condition score (BCS) on dairy cattle performance. Throughout the study, a total of 7956 dairy records were collected from six Holstein Friesian farms. According to the prepartum BCS, dairy cows were grouped into three main categories— low, medium, and over condition score cows for BCS values of 2–3, 3–4 and 4–5, respectively. Dairy cattles with BCS values under the level of 2 were culled as a part of culling policy in these farms. Productive parameters of milk yield (daily yield, 305-day yield and total yield), milk curve (days to peak, initial milk yield, peak milk yield and lactation persistency [LP]), milk somatic cell count (SCC) and somatic cell score (SCS), as well as some reproductive parameters (days to first estrus and days open) were determined to indicate the best dairy cattle prepartum BCS sustained high dairy performance. Prevalence of lameness and metabolic diseases (milk fever, abomasum displacement [DA] and ketosis) were also investigated in dairy cattle among different prepartum BCS. The best prepartum BCS was elucidated to reduce the prevalence of such diseases. Results of the present study revealed that the medium condition score cows produce more milk as compared to the over condition score cows. Medium condition score cows showed improved udder health and reproductive parameters. On the other hand, they showed decreased prevalence of lameness, milk fever, DA and ketosis. In contrast, it was obvious that over condition score cows suffered more from these metabolic disorders than low and medium BCS cows. The prevalence of lameness was more evident in low than in medium and over condition score cows.
... Numerous studies of microclimates have been conducted under controlled environments aiming at reducing the effects of heat accumulation on milk yield and fertility, for example by evaporative cooling achieved through a combination of sprinklers and fans (Her et al., 1988;Flamenbaum et al., 1995), but only a few have dealt with the contribution of barn design to the cow's response to heat stress especially for small holder dairy farms in tropical areas. In northern Thailand, the highest THI occurrs in the rainy season with the highest humidity and high temperatures causing the lowest reproductive performance in this area (Punyapornwithaya et al., 2005). ...
... It is interesting to note that the primiparous fat cows produces more milk than older fat cows and vice versa. The impact of BCS on subsequent milk production had been evaluated by many researchers who recorded that higher milk yield was strongly supported by moderate BCS (Mushtaq et al. 2012) while others reported that cows with high BCS had no advantage in milk production (Flamenbaum et al. 1995) or negative correlation between milk yield and body condition (Mikone et al. 2013). ...
The present experiment was carried out to know the effect of parities on body score, back fat thickness and milk yield of Jersey crossbred cows. A total of 43 crossbred jersey cattle were examined for 120 days postpartum and divided into four groups, based on their parity number. Correlation and relationship study has revealed significant effect of parity on various parameters. The overall correlation coefficient between BCS and BFT were found to be 54%, 92%, 94% and 90% for P1, P2, P3 and P4 respectively. However, positive to negative significant correlation between BFT and milk yield by parity 1,2,3,4 were 46%, 26%, -10% and -12% respectively. Increased BCS at calving was associated with greater MY in first and second parity cows, and reduced MY in cows of third parity or greater. Furthermore, the correlation coefficient between BFT and BW were found to be low in P1 (r=0.58) and high in P4 (r=0.78). The changes in body fat thickness (BFT) and body weight (BW) by parity difference were most distinct in younger cows i.e. -47.92 percent and -12.05 percent respectively. Relationship (R²) between BFT and BCS in different parity group were 0.29, 0.87, 0.85 and 0.83 respectively (p<0.001). Finally, in case of primiparous cow BFT is valid for estimation of subcutaneous fat and second parity onwards BCS can be adopted to predict the body fat reserve of crossbred animals.
... Si la temperatura ambiental alcanza valores por encima de los 20° C para los animales de origen templado y 26° C para los de origen tropical, se produce una falla en los sistemas de termorregulación, aumenta la temperatura rectal, disminuye el consumo de alimento, baja de la producción de leche con un cambio en su composición (Flamenbaum, 1995). Se ha reportado que la glándula mamaria se ve afectada en su desarrollo durante la etapa de preparto, disminuyendo la producción de leche en las siguientes lactaciones (Tao et al., 2012). ...
Los bovinos para cualquier propósito zootécnico son unidades de producción que funcionan bien o mal según se adapten o no al ambiente. Es indispensable saber cómo funciona un animal no solo por sus características físicas, sino también por sus cualidades de adaptación y sobrevivencia. El objetivo de este trabajo fue evaluar los efectos del Índice de Temperatura Humedad (ITH) sobre algunos parámetros reproductivos de vacas lecheras de la raza Holstein Friesian, se calculó también el ITH para limitar dos periodos; uno con ITH altos (73.6 a 76.3) entre abril y septiembre, y otro con ITH bajos (67.6 a 71.4) de octubre a marzo, se consideró como base para determinar estrés térmico al ITH. Al incrementar el valor del índice de temperatura humedad, los servicios por concepción se acrecentaron al igual que la presencia de fetos momificados (P˂0.01), esto indica que el estrés térmico provoca alteraciones en la fertilidad, así como problemas para el mantenimiento de la gestación. Poco se sabe de la influencia directa de la temperatura medioambiental sobre las anomalías reproductivas, por lo que se requiere de una mejora constante de las instalaciones y de un buen manejo para brindar el bienestar adecuado a los animales.
... La quantité de cétones présente dans le foie des vaches thermiquement stressées va elle aussi augmenter et ceci à travers la ß-oxydation des acides gras (Hao et al., 2016). Flamenbaum et al. (1995) et Ronchi et al. (1999) ...
... For example, farmers could invest in structures or plant trees to provide shade, though trees may be preferred because they provide better air circulation and can often have better cooling effects because of evapotranspiration. They could also invest in fans or cooling sprays (Flamenbaum et al. 1995;Her et al. 1998;Igono et al. 1987). ...
We use both biophysical and bioeconomic models to assess the impact of climate change on Honduran agriculture out to 2050. We find that for some key crops, such as maize and sugarcane, yield reductions will likely be larger in Honduras than most of the rest of the world will experience. We argue that the highest-value crop for Honduras—coffee—may also be the hardest hit by climate change.
... These findings were in accord with the reports of Mohammed et al. (1988) that cows with BCS of 2.5 produced less milk than those with 3 to 3.5. Flamenbaum et al. (1995) also reported that milk production for 150 days of lactation was greater for cows at higher BCS (3.80 ± 0.08) than for cows at low BCS (2.65 ± 0.07). Similarly, Pedron et al. (1993) observed that BCS was related (P<0.05) to peak production, and one unit of BCS was associated with 422 kg 305 day milk production in Holstein cows, the value being lower than the predicted values of the present study, ...
... Correa et al. (2002) reportaron una producción de 4 kg de leche/d más en vacas que fueron enfriadas a base de aspersores y abanicos durante 8 h continuas diariamente sobre vacas sólo con sombra. Otra alternativa de enfriamiento es la que realizaron Flamenbaum et al. (1995) los cuales enfriaron a vacas Holstein durante 11 h cada 2 h con lapsos de 30 min, obteniendo tan solo 1 L de diferencia en relación a vacas solo con sombra. Es necesario considerar otros aspectos que ayuden a reducir el estrés calórico como lo es el aspecto nutricional, ya que la energía liberada que resulta del metabolismo se encuentra íntimamente ligada con la termorregulación, digestibilidad y motilidad intestinal de la vaca (West, 1999), la reducción de la cantidad de fibra que se considera como un elemento que genera mucho calor, puede reducir el calor interno del animal (Cummnis, 1989), así también si modificamos la proporción de grasas, proteínas puede mejorar el desempeño fisiológico. ...
Dentro de las principales actividades de las Universidades Públicas se encuentra la investigación como parte del proceso formativo de los estudiantes, esta investigación no estaría completa sin la difusión de los resultados hacia los pares académicos, los interesados en el área y hacia el público en general.
Es en este contexto que nace el Foro de Investigación en Ciencias Agropecuarias ESCA-UAC en su tercera edición, con la participación de nuestros colegas de la Universidad de Colima, y la Universidad Autónoma de Campeche a través de la Escuela Superior de Ciencias Agropecuarias como un esfuerzo conjunto de difundir el quehacer científico de nuestra máxima casa de estudios y demás investigadores que amablemente nos hicieron llegar sus contribuciones científicas para su difusión a través de nuestro evento.
Prueba del acierto en este evento son los resúmenes que se encuentran en este documento, donde se tratan temas de interés para toda la comunidad como lo son los trabajos en reproducción, salud pública, sistemas de producción ovino, salud de las especies domésticas, genética, fauna silvestre y producción de leche y abejas.
Un especial agradecomiento a nuestros colaboradores por su paciencia para con los aciertos y desaciertos, que sabemos que en un futuro serán los menos, y finalmente a todas las personas que se involucraron en la organización de evento que tuvo como producto final el libro “Avances en la Investigación Agropecuaria en México”, el cual llego a buen fin, haciendo posible llegar a acuerdos de colaboración en ciencia y desarrollo tecnológico con nuestros pares.
Esperamos que esta obra resulte de gran ayuda para aquellos investigadores consolidados y aquellos que se inician en este arte de la comprensión-explicación de los fenómenos biológicos como lo fue para aquellos que vivimos la experiencia e intercambiamos ideas y conocimientos que sentarán las bases de los futuros trabajos de investigación.
Dr. Juan José Vargas Magaña
Compilador
... In Po Valley, northern Italy, Speroni et al. (2006) found 16% less milk yield after the start of the hot period regarding before the star of the hot period in multiparous dairy cows under milking parlor system. Following, diverse authors have shown their preoccupation respect to heat stress topic on milk yield in different parts of the world such as Missouri, Arizona, U.S., Israel, México, etc. (Igono et al., 1987(Igono et al., , 1992Her et al., 1988;Flamenbaum et al., 1995;Correa et al., 2002;Avendaño et al., 2006Avendaño et al., , 2010Adin et al., 2009). Also, St-Pierre et al. (2003) reported that heat stress greatly affected economic loss by the US dairy industry and that estimated losses ranged from $897 to $1,500 million, annually. ...
Authors' Contribution JAHR, JMO, LJGM, OFPR and RJMB wrote the initial manuscript. JAHR, JMO, ACGC, and MIU corrected the manuscript attending the reviewer's suggestions and language of the manuscript. Heat stress has severe effects in organisms. Dairy cattle is susceptible to suffer behavioral, physiological and reproductive damages due heat stress. Breeding searching for tolerant heat stress genes and their incorporation in crossbreeding programs has gained interest in dairy cattlemen concerned by the global warming and greenhouse effect in the environment. This review shows and update of the crossbreeding in dairy cattle in both hemispheres. Here, is reviewed the effect of heat stress on dairy cattle; the mechanism of autoregulation; the benefits of the heterosis in crossbreeding cattle by hybridization; the body condition score in crossbred dairy cattle; the yields in crossbreds; here is also discussed that even when there have been many crossbreeding in dairy cattle, but when the producer choose a system crossbreeding in dairy cows always mostly contemplate only body weight, body condition score, dry matter intake, and feed efficiency. Is suggested to contemplate other traits like genetic potential, lactation (305 d), lactation number, fertility rate, and economic impact to observe clarity the potential of each crossbred in dairy cattle in the future.
... The annual economic losses to the US dairy industry were estimated at $1.5 billion if cows were housed with only shade; however, this figure was reduced by 43% when the models included water spray and fans. 1 Indeed, when cows have access to soakers, both feeding time 42 and DMI increase in many studies, 52,57,58 and daily milk yields have been reported to be 1.5 to 3.7 kg higher. 20,59,60 Although the bulk of the research on cooling has focused on lactating cows, there is also a large body of evidence that heat stress in dry cows negatively affects their future productivity, fertility, and immune function, 61 as well as the performance, health, and survival of their offspring. 2,62 Because soakers and fans can mitigate these effects, recent models have indicated that providing heat abatement to dry cows is profitable. ...
Heat stress results in substantial economic losses to the dairy industry and is problematic for animal welfare. Soaking cattle with water is an effective form of heat abatement. This technique cools cattle when water evaporates from the skin and drips from the animal, and cools the microclimate. To evaluate cooling effectiveness and make appropriate adjustments to heat abatement, animal-based indicators should be recorded in addition to environmental measures. Ideally, heat abatement should be provided to all life stages of dairy cattle and soakers should be combined with shade.
... The reduction in appetite under heat stress is a result of elevated body temperature and may be related to gut fill. Most of the earlier workers reported lower RT, RR but higher DMI for cows receiving evaporative cooling than for cows in shed alone or under shed plus fan management system (Flamenbaum et al., 1995 andChan et al., 1997). Cooling may directly influence milk secretion from mammary gland, but its primary effect is to restore feed intake that has been suppressed due to elevated level of heat stress. ...
... The reduction in appetite under heat stress is a result of elevated body temperature and may be related to gut fill. Most of the earlier workers reported lower RT, RR but higher DMI for cows receiving evaporative cooling than for cows in shed alone or under shed plus fan management system (Flamenbaum et al., 1995 andChan et al., 1997). Cooling may directly influence milk secretion from mammary gland, but its primary effect is to restore feed intake that has been suppressed due to elevated level of heat stress. ...
Twenty-four Karan Fries cattle in early lactation with good body condition score (>3 at 6
point scale) were allotted four treatments randomly in summer to study the effect of
cooling in combination with altered fodder concentrate ratio on various production
parameters. Provision of cooling as well as higher concentrate allowances significantly
(P<0.05) improved the nutrients intake of the animals. Composition of various milk
constituents didn’t differ significantly (P>0.05) by feeding or cooling strategies. Animals
with access to evaporative cooling had greater milk yield than cows with fan alone.
Highest overall milk yield was recorded in T4 group cows (16.96 Kg/cow/day) followed
by T3, T2 and T1 cows (15.98, 13.99 and 13.07 Kg/cow/day) respectively. In conclusion,
higher concentrate allowances in the ration along with evaporative (T4) cooling system
was the best strategy to maximize production in summer.
... The reduction in appetite under heat stress is a result of elevated body temperature and may be related to gut fill. Most of the earlier workers reported lower RT, RR but higher DMI for cows receiving evaporative cooling than for cows in shed alone or under shed plus fan management system [11,8] . Cooling may directly influence milk secretion from mammary gland, but its primary effect is to restore feed intake that has been suppressed due to elevated level of heat stress. ...
24 Karan Fries cows in early lactation with good body condition (>3 at 6 point scale) were randomly allotted to four treatments to study the impact of modified microclimate on production performances. Treatments were; Shed (T1), Shed with fan (T2), Shed with fan and water bath (T3) and Shed with fan and sprinklers (T4). The T4 group had lower maximum, minimum, dry bulb as well as wet bulb temperatures and Thermal Humidity Index than other treatment groups. The rectal and skin temperatures, respiration and heart rates of animals were lower in T4 group. Composition of various milk constituents didn't differ significantly (P>0.05) by various cooling strategies. Higher milk yield was recorded for the animals which were provided evaporative cooling system. Highest overall milk yield was recorded in the animals of T4 group followed by T3, T2 and T1 groups. Thus, evaporative cooling system (T4) was proved to be the best strategy to maximize production in the summer season.
... The non-esterified fatty acid (NEFA) which is the metabolite of triglyceride had been studied by several researchers in relation to thermal stress. Reduction in plasma NEFA (Nonaka et al., 2008 andFlamenbaum et al., 1995) and increased use of NEFA as fuel in liver and peripheral tissues (Ronchi et al., 1999) ...
Heat stress and its implications on ruminants,buffaloes
... In controlled experiments, similar inconsistency was observed. The milk fat percentage of heat-stressed or noncooled cows was decreased (Moody et al., 1971), not changed (Knapp and Grummer, 1991;Flamenbaum et al., 1995;Tarazón-Herrera et al., 1999), or increased (Garner et al., 2016) compared with that of cows exposed to thermal neutrality or provided with cooling. ...
Heat stress reduces cow milk yield and results in a significant economic loss for the dairy industry. During lactation, heat stress lowers milk production by 25 to 40% with half of the decrease in milk synthesis resulting from the reduced feed intake. In vitro studies indicate that primary bovine mammary epithelial cells display greater rates of programmed cell death when exposed to high ambient temperatures, which may lead to a decrease in the total number of mammary epithelial cells in the mammary gland, partially explaining the lower milk production of lactating cows under heat stress. The function of mammary cells is also altered by heat stress. In response to heat stress, mammary cells display higher gene expression of heat shock proteins, indicating a need for cytoprotection from protein aggregation and degradation. Further, heat stress results in increased gene expression without altering protein expression of mammary epithelial cell junction proteins, and does not substantially influence the integrity of mammary epithelium. These data suggest that the mammary gland strives to maintain cell-to-cell junction integrity by synthesizing more proteins to compensate for protein losses induced by heat stress. During the dry period, heat stress negatively affects mammary gland development by reducing mammary cell proliferation before parturition, resulting in a dramatic decrease in milk production in the subsequent lactation. In addition to mammary growth, the mammary gland of the heat-stressed dry cow has reduced protein expression of autophagic proteins in the early dry period, suggesting heat stress influences mammary involution. Emerging evidence also indicates that heifers born to cows that experience late-gestation heat stress have lower milk yield during their first lactation, implying that the maternal environment may alter mammary gland development of the offspring. It is not clear if this is due to a direct epigenetic modification of prenatal mammary gland development by maternal heat stress. More research is needed to elucidate the effect of heat stress on mammary gland development and function.
... Investigaciones realizadas (17,18) muestran que los terneros nacidos de vacas refrigeradas en preparto presentan mayor peso (tanto como 10 %). Collier et al. (12,13) informaron que las vacas que durante su periodo de transición en verano fueron manejadas con sombra parieron terneros 3,1 kg más pesados que los animales sin sombra (39,7 vs. 36,6 kg). ...
Se utilizaron 30 vacas en preparto que se alojaron en un corral seco con acceso a sombra artificial durante el verano. Las vacas fueron distribuidas en dos grupos: sin refrescado (TS) y con refrescado (TR) en el sector comedero. El peso corporal y la condición corporal fueron evaluadas al inicio y a los 25 días. La frecuencia respiratoria se realizó dos veces por semana en cuatro momentos del día. El registro de comportamiento dos veces a la semana. Los datos de analizaron con t Student y χ2. El peso y condición corporal no presentaron diferencia signifi cativa. Se observó un efecto del tratamiento en el día y horario para la frecuencia respiratoria (p<0,0001). La conducta de parado a la sombra fue al que dedicaron mayor tiempo en ambos tratamientos 27 % en TS y 29 % en TR. No hubo diferencias en la producción lechera entre TS y TR: 31,4 l/v/d y 30,6 l/v/d respectivamente.
... Cows fed high quality RUP yielded 3.8 and 2.8 kg more milk under evaporative cooling and sheded environments, respectively, than those fed low quality proteins. Flamenbaum et al 23 ., examined the interactions between dietary manipulation for increased body conditions (3.8 vs. 2.7 on a six point scale) and post partum cooling (summer lactation). Milk production increased 1.9 kg/d with cooling, fat production increased with body condition and cooling, and protein production increased with cooling but not with body condition. ...
... Requirements for specific nutrients such as Na, K and Mg increases during thermal stress compared to ther moneutral conditions. At environmental temperature of 40°C, there is a 28-fold increase in the urinary excretion of potassium compared to cows maintained at 15°C (Flamenbaum et al., 1995). Therefore, in tropical conditions the microelement deficiencies in dairy cattle are quite common and frequent. ...
The present study was conducted to determine the effect of free choice salt and mineral licks on dry matter intake, milk yield, milk composition, blood biochemical parameters and micromineral profile in crossbred cows. Twenty four lactating Holstein Friesian crossbred cows were randomly distributed in 3 groups of 8 animals each based on milk yield. The cows in control group were fed basal ration to meet their nutrient requirements while tradition universal multi blocks and tradition fertility blocks/licks provided by Akzo Nobel were supplemented free choice in multi and fertility groups, respectively in addition to basal diet. The duration of the study was 120 days. The mean dry matter (DM) intake was similar in all the groups. The free choice multi and fertility licks increased the milk yield by 2 kg per cow per day as compared to control group where as multi lick also improved the milk fat and protein content. The control group had a lower persistency of milk yield during the experimental period as compared to multi and fertility groups. Supplementation of free choice multi and fertility licks did not affect levels of blood biochemical profile and monitored plasma micromineral content of crossbred cows.
... When cows had access to 1.3 or 4.9 L/min sprinklers, milk yield was, on average, 3.7 and 3.3 kg/24 h higher, respectively, compared with the control. Earlier studies in Israel's Mediterranean climate likewise found that intermittent spray increased milk yield by 1.5 to 2.6 kg/24 h on average (Her et al., 1988;Flamenbaum et al., 1995). Dry matter intake decreased on warmer days, but 4.9 L/min spray mitigated this relationship, consistent with what others have found when sprinklers are provided (Morrison et al., 1981;Strickland et al., 1989;Gaughan et al., 2004). ...
Dairies commonly mount nozzles above the feed bunk that intermittently spray cows to dissipate heat. These sprinklers use potable water-an increasingly scarce resource-but there is little experimental evidence for how much is needed to cool cows in loose housing. Sprinkler flow rate may affect the efficacy of heat abatement, cattle avoidance of spray (particularly on the head), and water waste. Our objectives were to determine how sprinkler flow rate affects cattle behavioral, physiological, and production responses when cows are given 24-h access to spray in freestall housing, and to evaluate heat abatement in relation to water use. We compared 3 treatments: sprinklers that delivered 1.3 or 4.9 L/min (both 3 min on and 9 min off, 24 h/d) and an unsprayed control. Nine pairs of high-producing lactating Holstein cows received each treatment at a shaded feed bunk for 2 d in a replicated 3 × 3 Latin square design [air temperature (T): 24-h maximum = 33 ± 3°C, mean ± SD]. Cows spent 5.8 ± 0.9 h/24 h (mean ± SD) at the feed bunk overall, regardless of treatment. With few exceptions, cows responded similarly to the 1.3 and 4.9 L/min flow rates. Sprinklers resulted in visits to the feed bunk that were on average 23 to 27% longer and 13 to 16% less frequent compared with the control, perhaps because cows avoided walking through spray. Indeed, when the sprinklers were on, cows left the feed bunk half as often as expected by chance, and when cows chose to walk through spray, they lowered their heads on average 1.7- to 3-fold more often than in the control. Despite possible reluctance to expose their heads to spray, cows did not avoid sprinklers overall. In warmer weather, cows spent more time at the feed bunk when it had sprinklers (on average 19 to 21 min/24 h for each 1°C increase in T), likely for heat abatement benefits. Compared with the control, sprinklers resulted in 0.3 to 0.7°C lower body temperature from 1300 to 1500 h and 1700 to 2000 h overall and attenuated the rise in this measure on warmer days (for each 10°C increase in T, body temperature increased by on average 0.5 to 0.7°C with sprinklers vs. 1.6°C without). Sprinkler access also resulted in milk yield that was, on average, 3.3 to 3.7 kg/24 h higher than in the control treatment. In this hot and dry climate, 1.3 L/min cooled cows more efficiently than 4.9 L/min, as the lower flow rate achieved equivalent reduction in body temperature and increase in milk yield relative to no spray, despite using 73% less water.
... Moreover, Deen et al. (2010) found that blood glucose was lower during summer months when compared to winter months at different weeks postpartum, from week 1 to week 6. The possible mechanisms by which heat stress reduces plasma glucose concentrations include reduced DMI (Abilay et al., 1975; Roman-Ponce et al., 1981; Flamenbaum et al., 1995), altered metabolic hormone secretion and the partitioning of energy to thermoregulation (Finch, 1986). Subclinical inflammation of the endometrium takes place in the absence of signs of endometritis, as determined by cytology (LeBlanc and Duffield, 2002). ...
A total of 65 multiparous cows that calved during the hot season (n = 21), temperate season (n = 23) or cold season (n = 21) were used to investigate the relationships between heat stress, seasonal changes, metabolic traits, body condition score (BCS), resumption of ovulation and occurrence of subclinical endometritis (SE). Cows were monitored for the first 7 weeks of lactation by ultrasonographic examination. Blood sampling and BCS evaluations were performed on a weekly basis. Plasma progesterone (P4) and blood metabolites related to energy status including beta-hydroxybutyrate, nonesterified fatty acids, total cholesterol, blood glucose and blood urea nitrogen were analyzed. Resumption of ovulation postpartum was confirmed by the first detection of a corpus luteum or a rise in P4 >= 1 ng/ml. Moreover, subclinical endometritis was diagnosed by brush cytology on day 40 +/- 2 of lactation and cows having polymorphonuclear cell percentages (PMN%) >= 5 were considered SE positive. As expected, mean temperature humidity index differed (P < 0.001) among hot (75-85), temperate (50-65) and cold seasons (35-45). The BCS in cows that calved during the hot season was lower (P < 0.001) when compared with those that calved during the cold and temperate seasons. The percentage of cows that resumed ovulation in the first 45 days of lactation was greater (P < 0.05) for those that calved during the hot season (90%) than the temperate season (60%). The concentration of NEFA was greater (P < 0.05) for cows that calved during the cold season than the hot season during different weeks postpartum. The concentration of glucose in weeks 4 to 7 postpartum was greater (P < 0.01) for cows that calved during the temperate season when compared to cows that calved during the hot season. There was no difference in the prevalence of SE according to calving season. The percentage of PMN tended (P < 0.1) to be greater in cows with SE during the temperate season than during the hot season. In conclusion, calving season may influence BCS, blood metabolites and resumption of ovulation whereas no association with prevalence of subclinical endometritis was observed.
... Similar results of increased milk production of 1.9 kg/day in dairy cows cooled by sprinklers and fans during summer [30] and 15% increase in milk yield in Friesian cows provided with ventilation and sprinkling during summer [31] corroborating the Values with different superscripts in a row differ significantly (p<0.001). SE=Standard error Values with different superscripts in a row differ significantly (p<0.001). ...
Aim: The aim of this study was to assess the effect of microclimate alteration on temperature-humidity index (THI), milk yield, and milk composition of Murrah buffaloes during summer for a period of 90-day from March to May-2014 at Buffalo Research Station, Venkataramannagudem, Andhra Pradesh, India.
Materials and Methods: A total of 40 lactating Murrah buffaloes were selected having similar body weight, parity, and milk yield. They were divided into four groups of 10 each. Three groups of buffaloes were provided with microclimate alteration using supplemental cooling like foggers, fans and foggers plus fans, and the fourth group (control) was without any cooling system. The daily THI was measured using dry and wet bulb thermometer. The physiological responses viz. rectal temperature, respiration rate, and pulse rate were measured by a clinical thermometer, measuring the flank movements a minute and observing the pulsation of the middle coccygeal artery at the base of tail with the help of finger. Milk samples were analyzed for chemical composition viz., fat, solids-not-fat (SNF), total solids (TS), specific gravity.
Results: In the present study, significant (p
... These fi ndings were in accord with the reports of Mohammed et al. (1988) that cows with BCS of 2.5 produced less milk than those with 3 to 3.5. Flamenbaum et al. (1995) also reported that milk production for 150 ...
A new body condition score (BCS) system was developed for Murrah buffaloes. The skeletal check points were identifi ed based on the anatomical features and carcass fat reserves. A new BCS chart with a 1-5 scale having 0.5 increments examining eight skeletal check points was developed. The ultrasonographic assessment of the precision of BCS system in 10 buffaloes for each point of the 1-5 scale indicated that BCS adequately refl ected the actual fat reserves. The infl uence of body condition score at calving (BCS) on the reproductive and productive performance studied in 24 (4 × 6 completely randomised design) and 40 (4 × 10 completely randomized design) buffaloes, respectively, revealed that buffaloes of BCSc group 3.5-3.99 showed the best performance among the four BCSc groups with earlier (P < 0.05) resumption of ovarian activity (29.33 days), a shorter (P < 0.01) postpartum an estrus period (46.66 days), a shorter (P < 0.05) service period (58.83 days), fewer services per conception (1.50), a higher rate of fi rst service conception (66.66%) with higher (P < 0.01) breeding effi ciency (90.64 percent). The milk production traits like total milk yield up to 18 weeks of lactation (1658.67 kg), 305 day predicted lactation yield (3187.3 kg), peak milk yield (16.5 kg), milk protein and solids not fat were also higher in BCSc of 3.5-3.99 followed by the BCSc groups of 4.0-4.49, 3.0-3.49 and 2.5-2.99.
... As cows were subjected to efficient feeding programs based upon dairy cattle body condition score, stage of lactation and lactation milk yield, in addition to mastitis control program and periodical estimation of the BCS and its adjustment during lactation length and dry off period maximized dairy production. The increasing of dairy cattle milk yield, the increasing of time needed to reach the top of milk curve, as thus due to high peak milk yield [17,18]. The results were in agreement with those of Refs. ...
The present study was conducted to detect the effect of management practice during the transition phase and prepartum body condition score (BCS) on dairy cattle performance. Throughout studying, a total of 7956 dairy records from six Holstein Friesian farms were collected. Dairy cows were allocated in three main transition systems (TS I, TS II, and TS III) according to their management practice during their transition phase. Moreover, within each transition system, dairy cows were regrouped into three categories according to their prepartum body condition scores, as low, medium, and over-condition score cows for BCS values of 2–3; 3–4, and 4–5, respectively. Cows which were under the level of 2 BCS were culled as a part of culling policy in these farms. Productive parameters of milk yield (daily yield, 305-days yield and total yield), milk curve (days to peak, initial milk yield, peak milk yield, and lactation persistency), milk somatic cell count (SCC) and somatic cell score (SCS), as well as some reproductive parameters (days to first estrus and days open) were determined to indicate the best dairy cattle transition management routine together with prepartum BCS sustained high dairy performance. Analysis of the collected data revealed that: TS I with periodical estimation and adjustment of BCS and efficient pre-and post-milking hygiene produced high dairy performance parameters and udder health condition (low SCC and SCS). Medium-condition score cows produced milk as much as over-condition score ones; however, they improved udder health, and reproductive parameters among all of dairy Holstein transition systems.
... It is difficult to cool dairy cows sufficiently to overcome humidity and heat during summer months in the southeastern U.S. Consequently, feed intake is depressed and milk production declines. Various methods of cooling (1,3,6,7,9,14,21,22) have been tried in an effort to minimize the effect of heat stress caused by higher temperature and humidity. ...
Forty-eight mid-lactation Holstein cows were assigned to one of four treatments and kept within an open freestall barn from June 13 to September 15, 1996. Treatments were 1) sprinklers in the feed alley plus misters over the freestalls; 2) sprinklers in the feed alley; 3) misters over the freestalls; 4) no water cooling. Fans over feed alleys and free stalls were on continuously when temperature exceeded 23.8°C. Sprinklers operated for four 3-min cycles/h and mist was on continually above 27.8°C. Cows were group-fed the same diet. Half the stalls were bedded with mortar sand and half with rubber-filled mattresses. Least squares means for the four treatments, respectively, were area PM temperature: 25.8b, 28.7a, 26.1b, 29.3a °C; area PM humidity: 89.6a, 72.1b, 87.2a, 68.3b%; respiration rate (per minute): 51c, 53c, 58b, 70a; rectal temperature: 38.7b, 38.7b, 38.7b, 39.1a °C; DMI: 24.3a, 23.5a, 22.0b, 22.5b kg/d; milk production: 23.6a, 22.1b, 22.0b, 21.2c kg/d; milk fat: 3.6, 3.6, 3.5, 3.6%; milk protein: 3.2a, 3.3a, 3.1b, 3.2a%; body weight gain: 0.38, 0.41, 0.31, 0.20 kg/d; and cooling water use: 3749, 3633, 428, 0 L/d. Water accumulation was not observed in the free stalls. Cows remained in free stalls more for the treatment with mist over the free stalls. Indicators of mastitis (SCC and bacterial culture) did not differ among treatments. Although cooling either area was advantageous, cows with mist in the free stalls and sprinklers at the feedbunk areas produced more milk than cows with either system alone.
... BCS was assessed on a 5-point scale (Ferguson et al. 1994;Flamenbaum et al. 1995) and the optimum was set at 3.50 scores with higher values deducted from 3.50, i.e. 3.75 was converted to 3.25, etc. This was necessary to appropriately reflect the optimum BCS in the modelling process. ...
The aim of this study was to check the effectiveness of classification and regression trees (CART), support vector machines (SVM) and generalized linear model (GLZ) in the detection of difficult calvings in the Polish Holstein-Friesian Black-and-White heifers and to identify the most influential predictors of such calvings with special regard to oestrogen receptor alpha (ERα) and cytochrome P450 (CYP19) aromatase genotypes. A total of 529 calving records containing four continuous and four categorical predictors were analysed. Calving category (difficult vs. easy) was a dependent variable. The most significant predictors were as follows: gestation length, body condition score index and calving age (for CART), as well as ERα genotype (for GLZ). Sensitivity (percentage of correctly diagnosed difficult calvings) and specificity (percentage of correctly diagnosed easy calvings) on a test set were 70.0% and 94.7% (for CART) as well as 50.0% and 99.0% (for SVM and GLZ), respectively. The studied models were characterized by good detection performance and high specificity and reliability of predictions.
... When cows had access to 1.3 or 4.9 L/min sprinklers, milk yield was, on average, 3.7 and 3.3 kg/24 h higher, respectively, compared with the control. Earlier studies in Israel's Mediterranean climate likewise found that intermittent spray increased milk yield by 1.5 to 2.6 kg/24 h on average (Her et al., 1988;Flamenbaum et al., 1995). Dry matter intake decreased on warmer days, but 4.9 L/min spray mitigated this relationship, consistent with what others have found when sprinklers are provided (Morrison et al., 1981;Strickland et al., 1989;Gaughan et al., 2004). ...
Abstract Text:
The accumulation of heat load can be problematic for dairy cow welfare and productivity. Sprinklers effectively reduce heat load, but little is known about the optimal amount of water needed for cooling, or about cattle behavioral responses to this resource. Two studies assessed how flow rate affected 1) the effectiveness of sprinklers and 2) cattle preferences. In Exp 1, 19 lactating cows were restrained at the feed bunk for 1 h/d and received 1 of 4 treatments in a crossover design: Control (0 L/min; 3x total) or sprinkler (0.4, 1.3, and ≥ 4.5 L/min, 6x each). Spray was delivered in 4 cycles (3-min on, 12-min off). Cooling effectiveness was evaluated using body temperature (BT) and respiratory rate (RR), by taking the differences between measurements recorded before the first spray cycle (-2 min) and after the final cycle (49 min). In Exp 2, 18 lactating cows were tested in a shaded Y-maze, with 3 pairwise comparisons between either the Control (0 L/min) and/or 0.4 or 4.5 L/min sprinklers. For each pairing, cows chose once daily (12 min/d) for 8 consecutive d. In Exp 1, BT and RR differed among all 4 treatments: as flow rate increased, so did cooling effectiveness (P < 0.01, GLMM). However, for BT there was an interaction with weather [volume*air temperature (AirT), P < 0.004]. At AirT < 28°C, both sprinklers ≥ 1.3 L/min kept BT from rising (P ≤ 0.003), whereas at AirT ≥ 32°C, only the ≥ 4.5 L/min sprinkler did (P ≤ 0.001). In Exp 2, cows tended to choose 0.4 L/min over Control 69% of the time (SE: 9.3%, P = 0.096, Wilcoxon signed-rank test), and showed no preferences in the other comparisons (4.5 L/min: 58% vs. Control, SE: 9.4%; 42% vs. 0.4 L/min, SE: 9.6%; P ≥ 0.552). However, preferences for 4.5 L/min over Control tended to depend on weather (P = 0.065, GLMM): at AirT ≤ 24.9°C, the probability of choosing 4.5 L/min was 0.40, whereas at AirT ≥ 30.0°C, this increased to 0.74. In conclusion, sprinkler flow rate influenced both cooling effectiveness and cattle preferences. In warmer weather, sprinklers ≥ 4.5 L/min were most effective, and were preferred over shade alone. However, more work is needed to fully understand how cattle choose to use cooling resources throughout the day.
Keywords: heat load, preference, sprinklers
... Concentration of cortisol in plasma decreases milk production. Exposure of cows to elevated ambient temperatures increases concentrations of cortisol in plasma therefore reducing milk production (Christison and Johnson, 1972;Flamenbaum et al., 1995). The establishment of milk production before gestation is vital to support for a beef cow to support a calf. ...
... These fi ndings were in accord with the reports of Mohammed et al. (1988) that cows with BCS of 2.5 produced less milk than those with 3 to 3.5. Flamenbaum et al. (1995) also reported that milk production for 150 days of lactation was greater for cows at higher BCS (3.80±0.08) than for cows at low BCS (2.65±0.07). ...
In the present study, an attempt was made
to compare the relative efficacy of different tests
used for diagnosis of brucellosis in buffaloes at
the field level. A total of 51 specimens, each of
milk and serum from clinically suspected subjects
in the field were studied. The true prevalence of
brucellosis was 13.72% with apparent prevalence
of 33.34% and 17.64% by the milk ring test
(MRT) and the Rose Bengal plate agglutination
test (RBPT), respectively. The overall agreement
between RBPT and serum tube agglutination test
(STAT) was higher (96.07%) as compared to MRT
and STAT (80.89%). Both MRT and RBPT showed
100% sensitivity. Specificity of RBPT was higher
(95.45%) than MRT (77.27%), when compared
with STAT. The positive predictive value of MRT
and RBPT was 0.412 and 0.778 respectively, with
both the tests having negative predictive value of 1
when compared with STAT. The kappa value also
revealed that RBPT and STAT had almost perfect
agreement (kappa value = 0.852), whereas MRT
and STAT (kappa value = 0.493) had substantial
agreement
... These fi ndings were in accord with the reports of Mohammed et al. (1988) that cows with BCS of 2.5 produced less milk than those with 3 to 3.5. Flamenbaum et al. (1995) also reported that milk production for 150 days of lactation was greater for cows at higher BCS (3.80±0.08) than for cows at low BCS (2.65±0.07). ...
In this study, thiamine-responsive
polioencephalomalacia (PEM) was detected in
seven non-descript buffaloes of a dairy farm in
Jammu and Kashmir State of India. Clinical cases
showed variable signs including disorientation,
aimless walking with a high stepping gait due
to blindness, anorexia, opisthotonus or head
retraction (star gazing), muscle tremor, convulsion
and recumbency. The result of the study of clinical
cases treated by parenteral injection of thiamine
preparation showed a good response within 12 h
after initial treatment. The immediate response
to the specific treatment coupled with the reports
of general hematology and other diagnostic test
used routinely in field was diagnostic for PEM and
differentiated it from other neurological conditions
based on the animals’ response to injection of
thiamine beside specific clinical findings
The negative consequences of heat stress on the dairy industry are substantial. Elevated ambient temperatures lead to a cascade of detrimental effects, including declines in productivity and elevated morbidity and mortality at various life stages, including pre- and post-weaning, during the dry period, and during lactation. The impacts of elevated ambient temperatures leading to heat stress in lactating dairy cows have been well-established. These include changes in autonomic and behavioral thermoregulation, reductions in dry matter intake, impaired immunity and health, altered mammary gene expression, and reduced milk production. More recently, heat stress implications on non-lactating cattle, for example, the dry dairy cow, have begun to be documented. Heat-stressed dry cows have altered immune function, metabolism, mammary development, and milk production in the subsequent lactation, even after the heat stress insult has been removed. Further, there is substantial evidence of maladaptive responses arising from late-gestation intrauterine hyperthermia, affecting multiple tissues and organs, and persisting as lifelong deficiencies lowering dairy cattle survival and productive potential. As predicted, climate change trends will continue to affect dairy cattle. There is an urgent need to develop practical strategies to effectively identify dairy cattle at risk of heat stress and offer interventions tailored to their age and physiological status to prevent the onset of heat stress in these animals.
Abstract. Body condition score is a well pointer of cows energy reserves during the lactation
season and can be a good measure of cows that are capable of balance well between milk
production and feed intake. From a review of researches, it was found the importance of
determining the body condition score in the management of dairy cows, as it is related to milk
production, reproductive performance and health status, as the over or excessive and low body
condition score has a negative impact on the general performance of dairy cows. Thus,
measuring the body condition may be an essential instrument in the management of cows to
increase milk production, improve reproductive performance and reduce the incidence of
health problems
Body condition score is a well pointer of cows energy reserves during the lactation season and can be a good measure of cows that are capable of balance well between milk production and feed intake. From a review of researches, it was found the importance of determining the body condition score in the management of dairy cows, as it is related to milk production, reproductive performance and health status, as the over or excessive and low body condition score has a negative impact on the general performance of dairy cows. Thus, measuring the body condition may be an essential instrument in the management of cows to increase milk production, improve reproductive performance and reduce the incidence of health problems.
2019
The present investigation was carried out to evaluate the effect of heat ameliorative measures (fans, foggers, green agro shadenet) on physiological, haematological, biochemical and milk production parameters in Surti buffaloes. Lactating Surti buffaloes (36) were equally divided into two groups and kept in two sheds. Group I animals were housed in a shed without any modification while Group II animals housed in a shed fitted with fans and foggers inside the shed and roof top white washed with microfine lime and open paddock was covered with green shade net and foggers were fitted. There were significant differences in the THI values of both inside and outside of the sheds at majority of periods during the hot-dry season. The floor and roof temperature of control shed at almost all-time intervals was significantly higher than the floor temperature of treatment shed. Significant difference in rectal temperature was observed at 14 and 28 days while respiration rate was significantly lower in animals of treatment shed. In treatment group, total erythrocyte count and haematocrit was significantly low at day 21 and mean platelet volume was significantly high at day 42. Significantly high levels of cholesterol, chloride and sodium at day 21 and glucose, protein, triglyceride, GSH, TAS and sodium at day 42 were observed in treatment group. Weekly milk yield (kg) during hot-dry season was significantly higher for treatment group than control group at 3rd, 4th and 5th weeks of the experiment. Evening milk yield of treatment group was significantly higher than the control and the cumulative milk yield (for 42 days) was also significantly higher for treatment group than control group (180.08 vs. 150.80 kg). It can be concluded that microclimate modifications help in reducing heat stress and has beneficial effect on physiological responses, blood biochemical parameters and total milk production in lactating Surti buffaloes during hot dry season.
Dentro de las principales actividades de las Universidades Públicas se encuentra la investigación como parte del proceso formativo de los estudiantes, esta investigación no estaría completa sin la difusión de los resultados hacia los pares académicos, los interesados en el área y hacia el público en general.
Es en este contexto que nace el Foro de Investigación en Ciencias Agropecuarias ESCA-UAC en su tercera edición, con la participación de nuestros colegas de la Universidad de Colima, y la Universidad Autónoma de Campeche a través de la Escuela Superior de Ciencias Agropecuarias como un esfuerzo conjunto de difundir el quehacer científico de nuestra máxima casa de estudios y demás investigadores que amablemente nos hicieron llegar sus contribuciones científicas para su difusión a través de nuestro evento.
Prueba del acierto en este evento son los resúmenes que se encuentran en este documento, donde se tratan temas de interés para toda la comunidad como lo son los trabajos en reproducción, salud pública, sistemas de producción ovino, salud de las especies domésticas, genética, fauna silvestre y producción de leche y abejas.
Un especial agradecomiento a nuestros colaboradores por su paciencia para con los aciertos y desaciertos, que sabemos que en un futuro serán los menos, y finalmente a todas las personas que se involucraron en la organización de evento que tuvo como producto final el libro “Avances en la Investigación Agropecuaria en México”, el cual llego a buen fin, haciendo posible llegar a acuerdos de colaboración en ciencia y desarrollo tecnológico con nuestros pares.
Esperamos que esta obra resulte de gran ayuda para aquellos investigadores consolidados y aquellos que se inician en este arte de la comprensión-explicación de los fenómenos biológicos como lo fue para aquellos que vivimos la experiencia e intercambiamos ideas y conocimientos que sentarán las bases de los futuros trabajos de investigación.
Dr. Juan José Vargas Magaña
Compilador
Present study was conducted on twenty four Surti buffaloes in their mid lactation to study the change in heamato-biochemical profile under different cooling system in hot-dry and hot-humid conditions. These animals were divided randomly into four groups based on body cooling systems provided i.e., without body cooling system (control, T1), fogging (T2), showering (T3), and wallowing (T4). Study was conducted in two phases with hotdry (April-May, 2012) and hot-humid (June-July, 2012) climate. Overall result of treatments showed that the afternoon percent THI was significantly (P<0.05) lower under showering (T3-80.65±0.17) than other treatments (T1-83.31±0.17, T2-81.94±0.15 and T4-83.31±0.17). Overall results showed that the mean value of Hb in gm % (T1-10.18±0.05 Vs. T2- 10.87±0.08, T3- 11.54±0.05 and T4-11.53±0.05), RBC count in million/mm³ (T1-6.54±0.04 Vs. T2- 6.99±0.04, T3-7.19±0.04 and T4-7.08±0.04) and WBC count in cells/μl (T1-15.56±0.08 Vs. T2- 16.62±0.08, T3-16.74±0.07 and T4-16.83±0.08) of Surti buffaloes was significantly lower in control group (T1) than cooling treatments (T2, T3 and T4). The mean value of PCV (%) during hot-humid condition was significantly (P<0.05) higher as compared to hot-dry condition in their respective treatments. Overall mean value of blood glucose in mg/dl (T1-61.48±0.55, T2-65.26±0.76, T3- 71.99±0.74 and T4-67.42±0.65), total protein in gm/dl (T1-7.74±0.05, T2-8.08±0.07, T3-8.15±0.09 and T4-8.44±0.07), BUN in mg/dl (T1-33.64±0.35, T2-35.23±0.41, T3-35.56±0.45 and T4-35.02±0.35), total cholesterol in mg/dl (T1-57.49±0.82, T2- 71.26±1.25, T3-82.64±1.16 and T4-89.26±1.14) and triglyceride in mg/dl (T1-31.76±0.68, T2- 34.02±0.65, T3-35.80±0.66 and T4-34.44±0.67) was significantly (P<0.05) lower in control (T1) than cooling groups (T2, T3 and T4). However, total protein in g/dl did not differed significantly between T1 and T2. Overall albumin concentration was significantly (P<0.05) higher under control (T1-3.99±0.04) than cooling systems (T2-3.38±0.05, T3-2.96±0.06 and T4-3.13±0.07). No definite trend was observed for various blood metabolites between hot-dry and hot-humid conditions.
The objective of this study was to determine the association among different housing and management practices on the prevalence of lameness, hock lesions, and thin cows on US dairy operations. This study was conducted as part of the National Animal Health Monitoring System's Dairy 2014 study, which included dairy operations in 17 states. Size categories were assigned as follows: small (30–99 cows), medium (100–499 cows), and large (≥500 cows). Trained assessors visited 191 dairy operations from March through July 2014 and recorded locomotion and hock scores (on a 3-point scale), and the number of thin cows (body condition score ≤2.25) from a total of 22,622 cows (average 118 cows per farm). The majority of cows (90.4%) were considered to be sound (locomotion score = 1), 6.9% were mild/moderately lame (locomotion score = 2), and 2.7% were severely lame (locomotion score = 3). Similarly, most cows (87.3%) had no hock lesions (hock score = 1), 10.1% had mild lesions (hock score = 2), and 2.6% had severe hock lesions (hock score = 3). A low percentage of cows (4.2%) were thin. Univariate comparisons were performed using PROC LOGLINK, which accounts for study design and weighting. Variables meeting the univariate screening criterion of P < 0.20 were eligible for entry into multivariable models. Statistical significance in the multivariable models was declared at P < 0.05. Large operations had a lower within-herd prevalence of cows with locomotion score ≥2 and locomotion score = 3 compared with small or medium-sized operations. Operations on which cows were kept primarily on pasture had a lower percentage of locomotion score = 3 than those housed in freestall or open/dry lot operations. The use of sand bedding was associated with a lower within-herd prevalence of locomotion score ≥2 than straw/hay or dry/composted manure as the primary bedding material. Sand bedding was also associated with a lower within-herd prevalence of locomotion score = 3 than other bedding types except for rubber mats or mattresses. Operations that housed cows in an open/dry lot had a lower percentage of hock score ≥2 and hock score = 3 than other housing types. Providing sprinklers for heat abatement and having a nutritionist balance rations for cows was associated with a lower percentage of thin cows. Results from this study highlight management practices that may reduce the prevalence of lameness, hock lesions, and thin cows on dairy operations in the United States.
Body condition is a very important factor for the estimation of metabolic energy reserves in cows. In this paper - the evolution of the estimation of body condition in cows has been presented. At present - especially in the USA - a 5 or 6 point body condition score (BCS) is in use. This scale allows for a reliable evaluation of the state of nourishment of cows and herds. A normal value of BCS in cows in different reproductive stages as well as-this score for Polish cows coming from individual or large farms have been given. The influence of body condition at drying off on post partum metabolic disorders, fertility, effectiveness of insemination and intensity of heat signs was demonstrated. Body condition also plays an important role during the supplementation of progesterone, synchronization of heat and/or effectiveness of embrio transfer. The relationship between body condition scoring and effectiveness of OPU and quality of in vitro produced embryos has been proved. The means by which the continuous monitoring of body condition enables the attainment of satisfactory results in reproduction are presented in the conclusion.
This investigation aimed at to analyse systematic influences on body condition scores (BCS) in Israeli-Holstein cows. Five kibbutz herds in Israel were selected for the study. The production units were situated in the coastal region of the Mediterranean. Milk production of cows was about 11,000 kg of milk in all herds with a fat content of 3.21% and a protein content of 2.87%. Herd size varied between 251 and 374 cows. The data recording began in October 1994 and ended in July 1995. Altogether, 770 cows of the Israeli-Holstein breed were included in the study. At 14-day-intervals condition scores on a scale of 1 to 5 with 0.25 increments judged at lumbar region, ischial and ileal tuberosities as well as the tail head region were recorded. Employing LSQ-models significant systematic effects on body condition scores showed kibbutz, lactation number, calving season and stage of lactation. The additive genetic influence of the sire on body condition scores was significant. The sire's influence on postpartum loss of condition and the subsequent gain was significant, the estimated heritabilities for condition loss being between 26% and 32%, for condition gain between 13% and 19%. Differences among cows in body condition scores may be explained to some extent by additive genetic effects what should be taken into account in recommendations for sire selection.
An experiment was conducted to find out the effect of housing systems and sprinkling water on crossbred cow during summer season in Kerala State. Providing shade significantly reduced the ambient temperature. Temperature and relative humidity did not differ due to sprinkling of water. Milk yield of cows in loose house with sprinklers was significantly higher. Heat stress increased the water intake and reduced the DM consumption. Sprinkling water on cows during hot hours of the day significantly reduced the water intake and increased DM consumption. The results suggest that during the summer season of Kerala loose housing and sprinkling of water may be practised to alleviate heat stress, increase DM consumption and augment milk production.
Holstein cattle performance is negatively affected by heat stress conditions. The objective of the present study was to determine the effect of a spray and fan cooling system on lactating cows performance under hot environment temperatures at Mexicali Valley, Baja California. Sixty one cows (2 to 5 lactations) were randomly assigned to one of two treatments at the start of the lactation period: a control group that had only shades at the central part of the housing pen (S); and a treated group that had a cooling system under the shade (E). This study lasted 135 d (May to September) with daily maxima temperatures between 39 and 49 °C and relative humidity between 30 and 50%. Cooled cows had higher (p<0.01) average milk production (30.5±0.94 kg/d) than control cows (26.6±0.98 kg/d). Fat and protein in milk were not different (p>0.05) between cooled (3.30±0.061 and 3.19±0.047%) and control (3.30±0.062 and 3.28±0.048%) cows, but somatic cell count average was higher (p<0.05) in the control group (313 919 ±120 503 cells) compared with the cooled group (293 019±118 542 cells). Breathing rate was greater (p<0.01) for S cows (87.8±1.8 breathings/min) than E cows (68.7±1.7 breathings/min). Pregnancy rate was higher (p<.05) in the S group (92%), than in the E group(50%). At the end of the experiment, body condition score was not different (p>0.05) between treatments. These results indicate that a cooling system based on spray and fans is an effective alternative to increase productive and reproductive efficiency in lactating Holstein cows under hot environmental conditions.
Many biologists have accepted the concept that the weather-sheltering effect of dense forest cover (i.e., thermal cover) reduces energy expenditure of large ungulates and therefore enhances survival and reproduction. Providing thermal cover for ungulates has become a key habitat objective for western elk ranges. However, it remains uncertain that thermal cover significantly influences the nutritional condition, survival, or productivity of wild ungulates. During 1991-95, we tested the hypothesis that the sheltering effect of thermal cover is of sufficient magnitude to enhance condition of elk (Cervus elaphus nelsoni) during summer and winter. Relative condition of captive young cows was monitored during 4 winter and 2 summer season-long experiments. These elk were placed in pens (2-3 elk per pen, n = 12 pens) at the center of 2.3-ha treatment units, each unit providing 1 of 4 levels of cover: (1) dense cover (≥70% forest canopy closure), (2) moderate cover (40-69% canopy closure), (3) zero cover (complete clearcuts), and (4) a combination of dense cover and zero cover. Controlled diets were set to induce moderate mass loss (5-10%) in winter and moderate growth in summer. Solar and net hemispherical radiation flux, windspeed, temperature, and relative humidity also were measured in the treatment units. We found no significant, positive effect of thermal cover on condition of elk during any of the 6 experiments. In contrast, dense cover provided a costly energetic environment, resulting in significantly greater overwinter mass loss, fat catabolism, and (in 1 winter) mortality. These results were consistent in all 4 winters despite variable temperature regimes ranging from mild to relatively severe. In summer, we found no significant effects of forest cover on condition or growth of yearlings, although elk in dense forest cover generally consumed less water than those in the zero or moderate cover treatments. Our data indicated that (1) the enhanced performance of elk with little or no thermal cover in winter was due to the greater levels of solar radiation flux and (2) potential energetic benefits of thermal cover (from reduced windspeed, elevated nocturnal temperature, and nocturnal long-wave radiation flux during winter, and shading from solar radiation in summer) were negligible in respect to the thermoregulatory capabilities of elk. We conclude that (1) thermal cover does not appreciably enhance the energetic status and productive performance of elk in climatological settings similar to those of our study, (2) providing thermal cover is not a suitable solution for inadequate forage conditions, and (3) habitat management based on the perceived value of thermal cover should be re-evaluated. Elk biologists should refocus their attention to the influences of forest management on (1) forage resources and related production potential of forest successional stages and (2) vulnerability of ungulates to harvest and harassment. Because the majority of empirical support for the thermal cover hypothesis is derived from observational studies of habitat selection, our findings amplify the difficulty associated with determining need or requirement, relevant in the context of population productivity, from empirical observations of habitat use.
Heat stress at the initiation of lactation negatively impacts the total milk production. Climatic conditions appeared to have maximum influence during the first 60 days of lactation when high-producing cows are in negative energy balance and make up for the deficit by mobilising body reserves. High-yielding cows are affected more than low yielding ones because the upper critical temperature shifts downwards as milk production, feed intake and heat production increase. High humidity seems to affect buffaloes less than cattle, since buffaloes may be superior to cattle in humid areas if shade or wallows are available. Heat stress causes the rostral cooling centre of the hypothalamus to stimulate the medial satiety centre which inhibits the lateral appetite centre and consequently lowers milk production. The heat-stressed cows depend on glucose for body energy needs; therefore, less glucose is directed towards the mammary gland, and there is a decline in milk production. Negative energy balance is associated with various metabolic changes that are implemented to support the dominant physiological condition of lactation. Marked alterations in both carbohydrate and lipid metabolism ensure partitioning of dietary-derived and tissue-originating nutrients towards the mammary gland, and many of these changes are mediated by endogenous somatotropin which is naturally increased during periods of negative energy balance. Milk constituents are greatly affected by hyperthermia. The ability to use powerful new tools in genomics, proteomics and metabolomics to evaluate genetic differences between animals in their response to thermal stress will yield important new information in the next quarter-century and will permit the selection of cattle for resistance to thermal stress.
Heat stress induces infertility in farm animals and represents a major source of economic loss to the livestock sector. The decrease in animal fertility is caused by elevated body temperature that influences ovarian functions, oestrous expression, oocyte health and embryonic development. Protection from heat stress during dry period is particularly crucial for a high-producing cow since it involves mammary gland involution and subsequent development, rapid fetal growth and induction of lactation. Cows and cycling buffaloes under heat stress have lower plasma inhibin concentrations, reflecting reduced folliculogenesis, since a significant proportion of plasma inhibin comes from small- and medium-sized follicles. Concentrations of plasma FSH are higher during the preovulatory period in summer and are associated with lower circulating concentrations of inhibin. The neuroendocrine mechanisms controlling gonadotrophin secretion are more sensitive to heat stress particularly in animals with low concentrations of plasma oestradiol. Environmental temperature and humidity 2 days prior to insemination is critical for conception than at any other phase of the reproductive cycle. A rise in rectal temperature diverts blood from the visceral organs to the peripheral circulation due to redistribution of blood to alleviate heat, which could reduce perfusion of nutrients and hormones to the endometrial and oviductal tissues affecting reproductive functions. In terms of steroid production, the thecal cells are more susceptible than granulosa cells to heat stress and express a delayed effect of heat stress in both medium-sized and preovulatory follicles. A rise in testicular temperature in bulls similar to other mammals with external testes leads to reduced sperm output, decreased sperm motility and an increased proportion of morphologically abnormal spermatozoa in the ejaculate. X and Y spermatozoa are affected differentially by high temperature. The plasma concentrations of insulin, IGF-I and glucose are low in summer months compared to winter months () probably because of low dry matter intake and increased negative energy balance. Insulin is required for the development of follicles and has beneficial effects on oocyte quality. Genetic selection for heat adaptability, both natural and artificial, is likely to modulate the impact of heat stress on reproductive functions, and therefore, genetic selection for thermal tolerance may be a necessity under climate change conditions.
A series of studies were carried out to investigate the effects of increasing environmental temperature (20°C, 28°C and 33°C) under a constant (80%) relative humidity (RH) on the physiological responses, utilization of nutrients and energy and nitrogen metabolism of Holstein heifers (n = 4, initial body weight = 251 ± 19kg, initial age = 10.1 ± 1.0 months). All the heifers were fed Italian ryegrass silage, Alfalfa hay cubes and concentrate to meet the heifer’s energy and protein growth rate of 0.8kg/day. The energy balance was measured daily by means of indirect calorimetry on the last 4 days of each temperature treatment. The results were as follows ; 1) The relatively high environmental temperature of 28°C with RH 80% increased the rectal temperature by 1.3°C and the respiration increased by 57 breaths per minute compared to the rectal temperature and respiration at 20°C and RH 80%. At 33°C with RH 80%, the rectal temperature and respiration rate increased by 2.2°C and by 73 breaths per minute, respectively, compared to those at 20°C and RH 80%. 2) Dry matter intake decreased at 28°C and above because of reduced roughage intake. As high environmental humidity reduced the latent heat dissipation from heifers even at 28°C, the increase in body temperature contributed to the decreased dry matter intake. 3) The effects of high environmental temperature on the dry matter digestibility of feed have been attributed to the reduction in the passage rate of digesta and the changes in feed composition because of the decreased roughage intake. 4) Blood alanine aminotrans-ferase, total cholesterol, glucose, alkaline phosphatase and triiodothyronine were significantly decreased as environmental temperature increased ; however, blood urea nitrogen increased. 5) Nitrogen and energy retention significantly decreased at 28°C and above, whereas nitrogen and energy digestibility increased. 6) At 20°C and 28°C, energy retention of body fat was higher than the energy retention of body protein, however, energy retention at 33°C was negative and body fat of the heifers was mobilized. These results show that the detrimental effects of high environmental temperature at 80% RH on the performance of Holstein heifers appeared at 28°C and above, and that the effects of high humidity were even more severe at 33°C.
Ninety-six Holstein multiple-lactation cows averaging 115 days in milk (DIM) and 60 Holstein first-lactation cows averaging 97 DIM at the initiation of a 10-wk study between June 10 and August 22, 1998 were used to evaluate the effectiveness of three different cooling sys-tems. Thirty-two multiparous cows and 20 first-lactation cows were assigned to each of three pens that contained different cooling systems. The three cooling systems consisted of : 1) a single row of 36-inch fans, spaced at 24-ft intervals over the freestalls and over the feed row, 2) 56-inch ceiling fans spaced at 12-ft intervals over the freestalls, and 3) polytube longitudinal cooling over the freestalls. Each of the three cooling systems utilized similar sprin-kler systems located over the feed line. Dry matter intake, respiration rates, milk production, and body condition scores were measured. Cows cooled with overhead 36-inch fans pro-duced more milk and had lower respiration rates than those cooled with other methods. The cows cooled with ceiling fans tended to produce more milk than those cooled via the polytube. Dry matter intake also tended to be greater for cows cooled by overhead 36-inch fans.
In two trials, three groups of eight dairy cows were fed for 2 months before calving to achieve condition scores at calving of 1·5 to 2 (low), 2·5 to 3 (medium) and 3·5 to 4 (high). For 16 weeks after calving, all cows were given a complete diet composed of silage, malt distillers' grains, barley, swedes and soya bean meal (metabolizable energy 12·25 and 12·35 MJ/kg dry matter in trials 1 and 2 respectively).
In both trials, significant differences were found between groups in dry-matter intake after calving. Cows that had higher condition scores at calving ate less and reached maximum intake of dry matter later than cows with lower condition scores (high, medium and low condition-score cattle attained maximum intakes in 14·5, 12·7 and 9·3 weeks in trial 1, and in 141, 9·6 and 7·9 weeks in trial 2). In trial 1, no difference was found in milk yield but, in trial 2, cows that had lower condition scores at calving produced slightly more milk. In both trials, cows that had higher condition scores at calving lost more body weight and condition, over a longer period, and started to regain the losses later than cows with lower condition scores. The biological efficiencies of milk production (energy output/energy input) from 8 weeks before calving until 16 weeks after calving were 0·302, 0·299 and 0·295 in trial 1, and 0·312, 0·290 and 0·306 in trial 2, for the low, medium and high groups respectively.
It was concluded that cows with lower condition scores at calving produced more milk directly from food rather than via body fat, were in positive energy balance earlier in lactation and over the total period were biologically more efficient than cows with higher condition scores. There appears to be no benefit from feeding cows to achieve a condition score greater than 1·5 to 2 at calving if high-energy complete diets are offered in early lactation.
Comparisons were made of the performance of cooled and uncooled cows housed under an open-side freestall barn located in a hot, humid environment. The effects of cooling in a nearby holding area were also studied. Average daily milk production for the cows cooled in the freestall barn was 20.2 kg (44.4 lb) versus 18.1 kg (39.8 lb) for uncooled cows (P < 0.01). Feed consumption increased from 17.8 (39.2) to 19.1 kg/day (42.0 lb/day) when cows were cooled in the freestall (P < 0.01) and from 18.3 (40.3) to 18.6 kg/day (40.9 lb/day) when cows were cooled in the holding area (P < 0.05). Milk protein content was increased from 3.39 to 3.51% by cooling in the freestall barn (P < 0.01). An economic analysis indicated that sprinkler and fan cooling systems offer advantages in hot, humid climates.
Twenty muhiparous and 16 primipar- ous Holstein cows were fed either a high energy or low energy diet during the dry period to achieve different degrees of body condition. Three weeks postpartum, cows were randomly assigned to either a high protein (23% CP) or a low protein (14.5% CP) diet. The diet contained 21% ADF during wk 3 through 6 postpartum and lowered to 9% ADF during wk 7 through 14 postpartum to depress fat test. Cows fed the low energy prepartum diet had less fat depression when fed the high protein postpartum diet com- pared with the low protein diet. Milk fat depression was more severe for all cows fed the high energy prepartum diet. De- pression in milk fat percentage for multi- parous cows was 30.8, 10.2, 34.5, and 26.0% for high energy-high protein, low energy-high protein, high energy- low protein, and low energy-low protein groups, respectively. For primiparous cows, milk fat depression was 37.3,24.1, 37.0, and 34.6%. After the fiber change, depression in acetate to propionate ratio was less for muhiparous cows fed high protein than for those fed low protein. Prepartum energy did not influence acetate to propionate ratio depression that resulted from the fiber change.
A scoring system with 1 to 5 scale was devised to measure body condition of dairy cows at any point during the lactation cycle. Cows were scored on appearance and palpation of back and hind quarters only. Relationships of body weight, frame size measurements, milk production, and characteristics related to the body condition scoring system were determined. During 18 too, 28 cows in each of 29 dairy herds were used for body measurements and body condition scores. Data were obtained from each herd at 3-mo intervals. Body weight and frame size measurements could not be correlated with body condition score. Dairy cows of greatest efficiency of milk production showed no significant increase in body condition during lactation, had fewer days open, but had lower per- sistency of lactation. Dairy cows that in- creased significantly in body condition during lactation were less efficient pro- ducers, had a greater number of days open, and had high body condition scores at the end of lactation. The body condition scoring system is a means of accurately determining body condition of dairy cows, independent of body weight and frame size.
To study their relationship to milk yield, the concentrations, in jugular venous blood, of thyroxine iodine (T4I), thyroxine (T4), 3,5,3'-tri-iodothyronine (T3), glucose, non-esterified fatty acids (NEFA), triglycerides, phospholipids, cholesterol, total protein, albumin, urea, haemoglobin and packed cell volume (PCV) have been measured in 36 cows (Simmental, Swiss Brown, Holstein and Simmental × Holstein) of different ages during a full lactation, pregnancy, dry period, parturition and 150 days of the ensuing lactation. Thyroid hormones and triglycerides were negatively, and total protein, globulin, cholesterol and phospholipids were positively, correlated with uncorrected or corrected milk yield during several periods of lactation, whereas glucose, NEFA, albumin, urea, haemoglobin and packed cell volume were not correlated with milk yield. The 10 animals with the highest milk yield (18·9 to 23·5 kg/day) exhibited significantly lower values of T4I, T4, T3 and glucose, significantly higher levels of total protein and globulin and tended to have higher levels of NEFA than the 10 cows with the lowest milk yield (10·9 to 14·3 kg/day) throughout or during certain periods of lactation, whereas concentrations of triglycerides, phospholipids, cholesterol, albumin, haemoglobin and PCV did not differ. Changes in T4I, T4, T3, glucose and total protein during lactation were also influenced by age, presumably associated with an increase in milk production with age. T3 was consistently lowest and cholesterol and phospholipids, during later stages of lactation, were highest in Holsteins, which had the highest milk yields of all breeds. Changes of blood parameters were mainly caused by shifts in energy and protein metabolism in association with level of milk production
An experiment with 25 dairy cows was performed to investigate the effects of different energy intakes on food intake, performance and blood hormone and metabolite levels during the last 70 days of pregnancy and the first 125 days after parturition. Compared with animals fed ad libitum before parturition, cows fed only according to requirements during the same time showed no decrease of food intake at calving. Cows fed at a restricted level also showed a faster increase in food intake, a smaller energy deficiency at the onset of lactation and a smaller weight loss after parturition. Peak milk yield was also lower, but the peak was maintained for a longer period, and during the first 2 months of lactation these cows had higher concentrations of glucose and lactic acid, and lower concentrations of non-esterified fatty acids and ketone bodies in the blood. Weight losses, and decrease of milk production during the 1st weeks of lactation were higher in cows fed only 0·75 of requirements during the first 60 days of lactation than in animals whose energy intake was planned to cover energy requirements, and during the first 2 months of lactation levels of unesterified fatty acids, ketone bodies and urea were higher, whereas levels of insulin, thyroxine and triiodothyronine were lower. Endocrine and metabolic changes seen during early lactation suggested improved glucose homeostasis, diminished fat mobilization and ketogenesis in cows given reduced amounts of energy during the dry period compared to animals fed ad libitum. To prevent the development of acetonaemia an adequate energy supply during the first part of lactation is, however, of greater importance.
From July 1975 to January 1977, 225 cows in three autumn-calving dairy herds were condition-scored, weighed and milk-recorded at monthly intervals. The condition score at calving was related to the ability of the animal to achieve potential milk yield. This potential milk yield was denned by the lactation curve prediction. Animals below condition score 2 at calving did not achieve their predicted milk yield, and those above condition score 2½ yielded more than their predicted milk yield. Cows in poor condition at calving gave low, late peak milk yields with a high persistency, and those in good condition at calving gave high, early peak milk yields with a lower persistency. A positive relationship of 25 ± 1·6 kg live weight per unit of condition score was established within cows in months 1 to 7 of lactation. After month 7 of lactation foetal development caused changes in live weight without changes in score.
Two groups of nine British Friesian cows were fed from about 32 weeks before calving to achieve condition scores at calving of 2·5 (thin) and 4 (fat). For 10 weeks after calving all cows were offered 7 kg hay daily in four feeds, with concentrates given five times daily according to appetite.
During early lactation, the group of fat cows had lower dry-matter intakes and daily milk yields and yielded less milk protein and lactose than the group of thin cows. The mean yield of milk over the whole lactation was 500 kg less in the fat cows but the difference was not significant. The fat cows lost 48 kg body weight and 1·20 units condition score during early lactation compared with 27 kg body weight and 0·52 units condition score in the thin cows. No difference in reproductive performance was found between the two groups but significantly more cases of disease occurred in the fat cows than in the thin cows.
It is concluded that cows that are fat at calving eat less than thin cows, give the same or less milk than thin cows, mobolize more body tissue and lose more weight after calving than thin cows and suffer more disease.
Thermoregulatory reactions of lactating cows (33 Kg milk/day) have been measured in summer (Tg 25° - 39°C) and in winter (Tg 9, 5° - 24°C) at 3-hr intervals, during four 24-hr cycles. The animals maintained an almost continuous peripheral vasodilation throughout the experimental period. The upper ambient temperatures at which a dairy cow maintains homoeothermy were calculated for different metabolic rates. At the maintenance level a dry cow may maintain homoeothermy at up to 24°C without sweating and up to 40°C if sweating at 50% of the maximal sweating capacity. For a cow producing 30 kg milk/day, the respective figures were 12°C and 24°C respectively. These data indicate that the thermoregulatory capacity of the animals in the natural climate considerably expands the thermal comfort temperature range.
Physiological factors affecting voluntary dry matter intake (VDMI) by cows were studied. An excess energy intake is often observed when low-yielding cows are consuming high energy diets. This does not suggest a regulation of intake such as to maintain energy balance. Variations of VDMI between animals and during lactation were analysed. Evidence was obtained for a good enough adjustment of intake to the cows' needs when highly "ingestible" and high energy diets are given, but a failure of this regulation is observed at the beginning and at the end of lactation. Some aspects of metabolic and hormonal control and of physical limitation of intake were reviewed and some practical consequences of the studies on voluntary dry matter intake regulation were drawn.
Weather data and breeding records for a Holstein herd of 1300 cows in Hawaii were evaluated to determine effects of climate on reproductive performance. The dairy is in a coastal climate near latitude 21 degrees N. Average maximum temperature, relative humidity, and resulting temperature-humidity index for the warmest month of the year were 31 C, 44%, and 79. Average minimum temperature and attending values for the same period were 20 C, 96%, and 68. From late April to November, conception rates were correlated negatively with the average temperature-humidity index of each day of the estrous cycle beginning 11 days prior to breeding. Slopes of regression lines differed, suggesting varying sensitivity of conception rate to heat stress on different days of the cycle. The temperature-humidity index of the 2nd day prior to breeding was most closely correlated with conception rate. Conception rates declined from 66% to 35% as the index increased from 68 to 78. Only the temperature-humdity index of the 2nd day prior to breeding had a significant partial correlation coefficient when the index of the 2nd and 1st day prior to breeding, the day of breeding, and the day following breeding were each evaluated with the index of the others held constant.
Six midlactation Holstein cows were exposed to treatments of thermal comfort environments with ad libitum or restricted (70% of ad libitum) DM intake and a thermal stress environment with ad libitum intake in two balanced 3 X 3 Latin squares to evaluate effects on mammary blood flow and other physiological measurements. Daily DM intake decreased from 17.8 kg in thermal comfort with ad libitum intake to 12.5 kg in thermal comfort with restricted intake and to 14.8 kg in thermal stress. Daily milk production decreased from 23.9 kg in thermal comfort ad libitum to 22.2 kg in thermal comfort restricted and 21.6 kg in thermal stress. Mammary blood flows (half udder) over the entire sampling interval (18 h) were 5.1, 4.3, and 4.5 L/min for treatments: thermal comfort, ad libitum intake; thermal comfort, restricted intake; and thermal stress, ad libitum intake. Mammary blood flows did not differ significantly among between treatments. Relationship of hald udder blood flow (L/min) to previous day's DM intake (kg/d) was described by the linear equation: L/min = .49 + (.27 kg/d); r2 = .46; and the quadratic equation: L/min = 6.04 - (.54 kg/d) + (.03 [kg/d]2); r2 = .55. Mammary blood flows 10 min before through 10 min after milking machine attachment were greater for cows at thermal comfort and ad libitum intake than for cows at thermal comfort and restricted intake or thermal stress and ad libitum intake (5.5, 4.8, and 4.8 L/min).
In trial 1, the effects of dietary energy (102, 131 or 162% of requirement) in the dry period and of sodium bicarbonate (0 or .75% of diet dry matter) in early lactation were assessed with 31 cows in a 3 X 2 factorial arrangement of treatments. Body condition and weight increased linearly with prepartum energy. Dry matter intake and milk yield were similar across treatments through 12 wk postpartum. Sodium bicarbonate increased milk fat content only in the 131% group, an effect apparently related to greater mobilization of fat in that group. In trial 2, energy treatments imposed in late lactation (145 to 55 d prepartum) and in the dry period (55 to 0 d) were 1) cows fed to requirement in both periods, 2) cows overfed in the first and underfed in the second period, 3) cows fed to requirement in the first and overfed in the second period, and 4) cows overfed in both periods. Cows in treatments 1 and 2 (normal) calved in a thinner state than those in 3 or 4 (fat). In the first 12 wk postpartum, intake did not differ, but cows in groups 3 and 4 produced more milk. Sodium bicarbonate imposed factorially postpartum increased milk fat content. Overconsumption of energy prepartum did not impair production when high energy total mixed rations were fed postpartum.
The reproductive performance of 74 Israeli Holstein dairy cows was examined during summer. Cows were fed prepartum to reach high (3.8) and low (2.6) body condition scores by 1 mo prepartum. After calving, half of each group were cooled seven times a day for 30 min by sprinkling and ventilation. Cows were inseminated starting 60 d postpartum. Daily mean body temperatures of cooled and noncooled cows were 38.6 and 39.2 degrees C, respectively, with differences between them reaching 1 degree C and more during the hot hours. Body condition affected only the time taken postpartum to the start of ovarian activity (26 d for high and 32 d for low body condition groups). Estrous behavior lasted longer in cooled (16 h) than in noncooled (11.5 h) cows of the low body condition group only. Conception rate was higher in cooled than in noncooled cows (59 vs. 17%). Pregnancy rate at 90 d postpartum was higher in cooled (44%) than in noncooled cows (14%). Progesterone concentrations were higher in inseminated nonpregnant and in noninseminated cyclic cooled cows than in noncooled cows and were similar in pregnant cows of both cooled and non-cooled groups. The present cooling method appears to have a high potential for improvement of summer fertility.
Effect of cooling on body temperature, milk production, estrous behavior, and reproductive performance was examined in 66 estrous-synchronized, Israeli-Holstein dairy cows. Cooling was by an automated system, which actuated sprinkling (30 s) followed by forced ventilation (4.5 min) for 30-min periods. Cows were cooled 9 times/d between 0500 and 2100 h over 10 d, starting 1 d before expected estrus until d 8 post estrus. Cooling reduced typical diurnal rise of body temperature in summer heat-stressed cows by .5 to .9 degrees C, and body temperature was maintained close to normothermic temperature (38.6 degrees C). Milk production of cooled cows was 2.6 kg/d (+8%) above control at end of the cooling period. More cooled cows than noncooled exhibited standing estrous behavior; in noncooled cows, silent ovulations or anestrus were more frequent. Conception rate of cooled cows did not differ from control, suggesting need for a longer than a 10-d cooling period for improvement of fertility. The cooling system has potential to alleviate heat stress in dairy cows and to improve their thermal balance, productive, and reproductive performances.
A method for cooling dairy cattle based on repeated wetting to attain maximal water trapping in the coat, followed by its rapid evaporation by using forced ventilation has been examined. Effects examined include duration of wetting, duration of cooling, and density of the animals in the holding area. The coat was wetted by inverted static sprinklers. Also examined was the extent to which the diurnal increase in rectal temperature can be prevented. The maximal decrement of temperature was attained at 30 min after cessation of cooling in all trials. Wetting the coat for 10 s was less effective than for 20 or 30 s; the latter did not differ in their effects. Cooling animals for 15, 30, and 45 min produced decrements in temperature of .6, .7, and 1.0 degrees C, respectively. Maintaining animals at a density of 1.9 m2/cow in the holding area reduced to about half the decrement as compared with a density of 3.5 m2/cow. When cows were cooled 5 times per day for 30 min, temperatures were maintained within 38.2 to 38.9 degrees C during the day, which were significantly lower than for those not cooled.
Lipolytic adaptations of bovine adipose tissue during late pregnancy, lactation, and dry period were studied in Holsteins. Treatment groups consisted of first lactation daughters of high or low bulls based on Predicted Difference for milk. Heifers were fed either a 60% concentrate, 40% hay diet or a 40% concentrate, 60% hay diet from 0 to 140 d lactation. Feeding a low energy diet for the first 140 d of lactation did not affect adipose tissue lipolytic rates measured in vitro. Epinephrine and norepinephrine responsiveness of bovine adipose tissue increased prior to parturition, increased further in early lactation, then remained elevated during lactation and into the dry period. This responsiveness was unaffected by feeding low energy diets. Basal glycerol release in high genetic merit heifers was 64, 17, 40, 23, 20, and 42% greater than in low genetic merit heifers at -30, -15, 30, 60, 180, and 349 d about parturition. Response to norepinephrine was 15, 20, 18, and 15% greater in high genetic than low genetic merit heifers and response to epinephrine was 12, 20, 14, and 50% greater in high genetic than low genetic merit heifers at 30, 60, 180, and 349 d postpartum. The lack of a dietary energy restriction effect on lipolysis in early lactation suggested that these rates were near the physiological maximum for those animals. Rates of lipolysis were positively related with milk fat production. This study indicates a genetic component in adrenergic regulation of lipolysis in adipose tissue, independent of energy balance, in supporting lactation.
During the 1984 summer, effects of spray and fan in freestall areas and feeding areas on milk yield, plasma growth hormone and prolactin, freestall utilization, and economic significance for Holstein cows were studied. Weekly milk and rectal temperatures at morning and afternoon milkings were higher for cows in shade than in shade with spray and fan cooling. Compared with rectal temperature, milk temperature measured in the clawpiece provided a more reliable indicator of heat stress than in the milk meter. Diurnal pattern of rectal temperature from 4-h measurements showed an average of 12 h in which maximal rectal temperatures of cows in shade were greater than 39 degrees C, but cows in the shade plus spray plus fan group had rectal temperatures below 39 degrees C all day. Plasma growth hormone was higher and prolactin lower for cows in shade plus spray and fan than cows in shade only. Cows cooled with spray and fan under shade produced 2 kg/cow per d more than cows in shade alone. Economic analysis showed a net income of 22 cents/cow per day for spray plus fan under shade. Results suggest that milk temperature is a practical technique to assess heat stress in dairy cattle, and the use of spray plus fan is a profitable means to maximize cow comfort and lessen stress-induced decline in milk production.
Digestible energy levels of 115% (low- prepartum) and 160% (high-prepartum) of maintenance requirements were pro- vided for groups of 32 Holstein cows dur- ing the last six to eight weeks of gesta- tion. All 64 cows were factorially assigned to two energy levels postpartum. One group was fed concentrates sufficient to maintain body weight through a complete lactation (high-postpartum). The second group was fed according, to the energy requirements of lactation recommended by the National Research Council in 1958 (low-postpartum). Unadjusted 305-day yields of milk, fat, protein, and lactose plus minerals were 5,600, 193.6, 190.4, 298.2 (low-prepartum-low-postpartum) ; 7,002, 223.0, 233.6, 367.2 (low-prepartum- high-postpartum) ; 6,223, 210.9, 208.6, 327.7 (high-prepartum-low-postpartum) ; 6,534, 210.9, 220.9, 337.2 kg (high-prepartuln- high-postpartum), respectively. Prepar- tuna energy levels did not significantly (P < .I)5) affect milk or milk component yields, but the higher postpartum level increased (P < .05) production of milk, protein, and lactose without affecting (P < .05) percentages of milk compo- nents. Oleic acid was increased (P < .05) in milk (Weeks 3 ~o 4) from cows receiving the high prepartum level and'palmitic acid was significantly higher (P < .05) from cows offered the high postpartum level (Weeks 15 to 16). Clinical ketosis and elevated blood ketones were more preva- lent (P < .05) in cows offered the high prepartum level, and were most pro- nounced in the high pre-low-postpartum sequence. An average of 1.86 megacal of digestible energy was required per kilo- gram of solids-corrected milk to maintain
We have studied the effects of 60-min infusions of dopamine (DA), norepinephrine (NE), epinephrine (E), isoproterenol (ISO), phenylephrine, phentolamine, and propranolol alone, of 60-min infusions of NE, E, and ISO in the presence of propranolol, and of 7-min infusions of ISO in the presence of phenylephrine on FFA levels in blood plasma of cows, heifers, and steers fed according to requirements. The effect of 60-min infusions of propranolol on FFA levels was also studied in steers fasted for 4 days. In addition, plasma levels of FFA, free glycerol, glucose, lactic acid, and E were measured during E infusions before and after 4 days of fasting in steers. Plasma FFA increased during NE, E, ISO, and phentolamine infusions, whereas DA and phenylephrine had no effect. Propranolol inhibited the effects of NE, E, and ISO on FFA. Propranolol alone had no significant effect on FFA levels in fed animals, but lowered the elevated FFA levels in fasted animals. The increases in FFA and glycerol during E infusions were more marked in starved than in fed animals, whereas the increases in glucose and lactic acid were smaller. Basal plasma E concentrations were similar in fed and fasted animals, but plasma E increased to higher levels during E infusions in starved than in fed animals. The data suggest that in cattle, as in other species, beta-adrenergic agonists and beta-adrenergic components of catecholamines elevate plasma FFA, whereas alpha-adrenergic agonists and DA have apparently no effect or no direct effect. Low plasma insulin levels, exposition of fat cells to higher circulating levels of E during E infusions, and decreased reesterification of FFA in starved compared to fed animals may contribute to increased lipolytic activity and the enhanced FFA response to E infusions during fasting.
Hot weather causes heat stress in dairy cattle. Although effects are more severe in hot climates, dairy cattle in areas with relatively moderate climates also are exposed to periods of heat stress. The resultant decrease in milk production and reproductive efficiency can be offset by implementation of a program consisting of cooling through shades, ventilation and spray, and fans. The economic benefit should be determined before installation of equipment to reduce heat stress.
Out of 128 surveys mailed to dairy farms that had been identified by the nine DHI processing centers as the top milk producing herds in the country, 61 surveys were returned. The predominant forage being fed was corn silage, followed by legume hay and haylage. On average, 6.7 feed additives and 3.5 alternative feeds were fed. Producers reported the following incidences of metabolic disorders: parturient paresis, 7.2%; displaced abomasum, 3.3%; ketosis, 3.7%; and nonspecific downer cow syndrome, 1.1%. Producers scheduled detection of estrus 3.1 times per day. Only 18.3% of the herds used routine synchronization of estrus. Artificial insemination was used on 94.8% of the cows and 88.5% of the heifers. The most important trait in sire selection was PTA for milk. For mastitis control, 75.4% of the producers practiced predipping, 85.2% used individual paper towels, 93.4% practiced postdipping, and 95.1% treated all cows at cessation of milking. Increased profitability and lower costs or higher returns were the primary motivators of these producers. Veterinarians were the most frequent source of information, followed by farm magazines. Satellite delivery of educational programs was the least acceptable delivery method. Extension professionals need to be cognizant of the producers' preferred information sources and delivery systems to ensure accurate, timely, cost-effective transfer of technological advances.
Practical relationships were determined between milk production, health, and reproduction with the amount and use of body fat in high producing lactating Holstein dairy cattle. Approximately 350 cows and heifers > 15 mo of age in a high producing herd were assigned body condition scores at monthly intervals for 24 mo. Production of 305-d FCM averaged 9541 kg (range 8826 to 10,818 kg). Body condition score at each of four calvings at 30, 60, 90, 120, and 305 DIM in each parity and loss in score in each lactation were summarized. Multiple regression related scores to milk and milk fat production, reproduction, and disease variables within and among lactations. No difference in score occurred at calving or at dry-off among parities. The range of body condition scores was less than is commonly reported; however, loss of condition increased with increasing parity from .3 in first lactation to .9 body condition score units in lactations > or = 4. The body condition score varied quadratically with DIM but, at a given DIM, was not related to the daily milk production on that DIM. Parity had a stronger relationship with milk and milk fat production than did body condition score. However, within lactation, body condition score at calving and the loss of score were related quadratically to milk production. No significant relationships of body condition score to the incidences of pyometra, metritis, retained placenta, cystic ovarian disease, AI per conception, days to first AI, or dystocia existed in this herd.
Twenty-four Holstein cows in midlactation during summer in southern Arizona were fed diets supplemented with a combination of blood, fish, and soybean meals (high quality protein) or corn gluten meal (low quality protein). Diets were balanced for CP content and estimated ruminal protein degradability, but they differed in Lys concentration (.98 vs. .59% of DM). Milk yield for the 56-d trial was higher by 11% for cows fed high than for cows fed low quality protein and higher by 9% for cows receiving evaporative cooling plus shade than for cows receiving shade alone. Milk fat and protein yields also were greater for high than for low quality protein and for evaporatively cooled plus shade than for shade treatments. Intake of DM tended to be higher for cooled cows but was unaffected by protein source. Cooled cows had lower rectal temperatures (38.6 vs. 39.1 degrees C) and respiration rates (64 vs. 82/min) than noncooled cows. Interactions between protein quality and cooling method were not statistically significant; however, cooled cows fed high quality protein had higher milk yield than noncooled cows. Digestibility of DM was higher for the low than for the high quality diet, but CP digestibilities were not different. Cows fed supplemental protein of higher Lys content were more productive.
Hyperthermia and body energy store effects on fertility and ovarian function in dairy cows
- Wolfenson
The effect of body condition at calving on the production of Friesian cows and heifers
- Land
The relationship between thermal state and distribution of cardiac output in the rabbit
- A Lublin
Environmental modifications to improve production and fertility
- Berman