Article

The Effect of Extended Calving Intervals in High Lactating Cows on Milk Production and Profitability

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Abstract

A field trial was conducted to examine the effect of extended calving interval (CI) on production and profitability of high yielding cows (n = 937). First insemination was performed at 154 and 93 d postpartum (pp), for treatment and control primiparous cows, respectively, and at 124 and 71 d pp for treatment and control multiparous cows, respectively. During the first experimental lactation, average daily value-corrected milk (VCM) yield was 28.5 and 27.7 kg/d of CI for treatment (n = 131) and control (n = 133) primiparous cows, respectively. No significant difference in average daily VCM yield (33.0 and 32.8 kg/d of CI) was found between treatment (n = 271) and control (n = 215) multiparous cows . In the first 150 d of the subsequent lactation, there were significant differences in milk and VCM production in favor of the treatment primiparous cows (41.4 vs. 39.7 kg of VCM/d) but no significant differences in the production of multiparous cows. Primiparous and multiparous cows with extended lactations were more profitable. During the first experimental lactation, there were advantages of 0.19and0.19 and 0.12/d of CI in the net returns for primiparous cows and multiparous cows with longer CI, respectively. When the economic analysis included the first experimental lactation plus the first 150 d of the subsequent one, the net return per day of CI was higher for cows with an extended voluntary waiting period: 0.21/dand0.21/d and 0.16/d for primiparous and multiparous cows, respectively. A delay of 60 d with respect to the usual voluntary waiting period in the beginning of inseminations of high yielding cows has economic advantages and allows the farmer an option for decisions regarding individual cows.

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... Controlled EL studies, where one or more experimental groups of cows with EL were compared with a control group with a lactation length close to 10 months are shown in Table 1. All studies conducted under high-input conditions with high-producing dairy cows, often fed a total mixed ration (TMR), indicated that there is very little to no adverse effect of EL on average daily milk yield compared with control lactation lengths (van Amburgh et al. 1997;Rehn et al. 2000;Arbel et al. 2001;Österman and Bertilsson 2003;Lehmann et al. 2016, Niozas et al. 2019aBurgers et al. 2021a). In fact, Edvardsson Rasmussen et al. (2023b) found a higher daily yield in second-lactation, but not first-lactation, cows on EL across 16 commercial herds. ...
... In a number of studies, the effect of parity (i.e. primiparous versus multiparous cows) on milk yield during EL was investigated (Rehn et al. 2000;Arbel et al. 2001;Lehmann et al. 2016;Niozas et al. 2019a;Jarman et al. 2020;Burgers et al. 2021b). Although peak lactation yield may be lower in primiparous cows, they overwhelmingly exhibited greater lactation persistency during the EL period and therefore maintained lactation better than did multiparous cows during EL. ...
... For EL to become an acceptable on-farm management tool, its implementation has to be at least cost-neutral and preferably increase farm profitability. A number of studies have been conducted to quantify the economic impact of EL, on the basis of actual farm data (van Amburgh et al. 1997;Arbel et al. 2001;Malcolm 2005;Butler et al. 2010;Browne et al. 2014;Dalcq et al. 2018;Burgers et al. 2022) or on simulated scenarios (Rotz et al. 2005;Inchaisri et al. 2011;Kok et al. 2019;Lehmann et al. 2019). Although most studies have indicated a neutral or positive impact of EL on profitability, it is difficult to draw firm conclusions, given the range of models, input variables and assumptions employed and different durations of EL (Table 5). ...
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Traditionally the lactation cycle of a dairy cow is based around a 12-month calving interval, allowing for 10 months of lactation, followed by a 2-month dry period. This means that the cow has to conceive within 2–3 months after calving, when she is also at peak lactation and metabolically is in a negative energy balance. Such challenging physiological conditions make it challenging for the cow to conceive at this time and many modern high-producing cows fail to get pregnant within the constraints of a 12-month calving interval. In addition, many cows still produce at a high level at drying-off time, increasing the risk of intramammary infections. Therefore, delaying conception past peak production and, as a result, extending the lactation beyond 10 months may increasingly be necessary. Additionally, extended lactation (EL) may offer other advantages such as fewer calves being born and thus fewer ‘surplus’ calves needing to be culled at a young age, fewer health and welfare issues and improved environmental outcomes (i.e. less greenhouse-gas emission; less antibiotic usage) during the lifetime of the animal. Extending lactation is a straight forward management practice in high-input dairy systems where a consistent supply of feed supplements is readily available, but may be more challenging to implement in low(er)-input pasture-based systems. The latter are much more seasonal, with a 12-month calving interval allowing pasture growth and quality to match the cow’s nutritional demands; cows calve in spring when high-quality pasture is abundant and are dried-off during winter when pasture growth is more limited. In this review, we explored the impact of EL in both high-input systems and pasture-based systems. It covers the effects of EL on milk production, composition and processing, as well as on reproductive performance, health and welfare, and environmental and economic outcomes.
... Extending the VWP results in longer lactation lengths and calving intervals (Van Amburgh et al., 1997;Rehn et al., 2000;Arbel et al., 2001;Österman and Bertilsson, 2003;Stangaferro et al., 2018a, b;Niozas et al., 2019a;Burgers et al., 2021b). Longer lactations prolong the period of late lactation, where milk production is generally lower, yet increase the number of lactating days relative to dry days. ...
... In most of the reviewed studies, a longer VWP resulted in a lower MY/CI for multiparous cows, and [a higher MY/CI] for primiparous cows (Figure 2), while in several studies VWP length had no significant effect (Rehn et al., 2000;Arbel et al., 2001;Österman and Bertilsson, 2003). Within multiparous cows, yield of cows with a VWP of 200 d was lower than that of cows with a VWP of 50 d when expressed as fat-and-protein-corrected milk per day of calving interval (Burgers et al., 2021b), and within primiparous cows, yield of cows with a VWP of 150 d was higher than that of cows with a VWP of 90 d when expressed as value-corrected milk per day of calving interval (Arbel et al., 2001). ...
... In most of the reviewed studies, a longer VWP resulted in a lower MY/CI for multiparous cows, and [a higher MY/CI] for primiparous cows (Figure 2), while in several studies VWP length had no significant effect (Rehn et al., 2000;Arbel et al., 2001;Österman and Bertilsson, 2003). Within multiparous cows, yield of cows with a VWP of 200 d was lower than that of cows with a VWP of 50 d when expressed as fat-and-protein-corrected milk per day of calving interval (Burgers et al., 2021b), and within primiparous cows, yield of cows with a VWP of 150 d was higher than that of cows with a VWP of 90 d when expressed as value-corrected milk per day of calving interval (Arbel et al., 2001). Niozas et al. (2019b) found a similar production per day in lactation for cows with a VWP of 40, 120, or 180 d, with an increase in lactation length of 106 d and an increase in dry period length of 10 d for a VWP of 180 d, also implying that MY/CI was not affected. ...
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Approximately 150 million households around the globe are engaged in milk production. In most developing countries, milk is produced by smallholders, and milk production contributes to household livelihoods, food security and nutrition. Milk provides relatively quick returns for small-scale producers and is an important source of cash income. In recent decades, developing countries have increased their share in global dairy production. This growth is mostly the result of an increase in numbers of producing animals rather than a rise in productivity per head. In many developing countries, dairy productivity is constrained by poor-quality feed resources, diseases, limited access to markets and services (e.g., health, credit and training) and dairy animals’ low genetic potential for milk production. Unlike developed countries, many developing countries have hot and/or humid climates that are unfavourable for dairying. Traditionally, dairy farmers are recommended to aim for a 1-yr calving interval, as this would maximize milk production and income. Longer calving intervals would extend the period in late lactation, when milk production is lower. However, there may be several reasons to re-evaluate the traditional lactation length, including increased productivity of modern dairy cows, and potential benefits of longer lactations for cow health and welfare. Moreover, although farmers are advised to aim for a 1-yr calving interval, in practice calving intervals mostly exceed 1 yr. Some cows might be better suited for an extended CInt than others, due to differences in milk yield level, lactation persistency, or health status, which would justify a customized CInt based on individual cow characteristics. This study aims to investigate 13 farms with customized CInt, with respect to calving to first service interval (CFSI), accomplished CInt, services per conception (SC), conception rate at first artificial insemination (CR1AI), peak yield, lactation persistency, 305-d yield, and effective lactation yield. In total, 4,858 complete lactations of Holstein Friesian cows between 2012 and 2022 from the 13 farms were grouped by parity and CFSI or CInt.
... [5][6][7] Evaluating the reproductive efficiency of a given dairy farm is an essential element; whether the farm is running with profit. 8 Important indicators have to be included during the monitoring and evaluation system. Parameters such as age at first service, age at first calving, calving interval, and service per conception and so on has to be included in order to evaluate day to day activity, monitor the progress, analyze and interpret farm status. ...
... The total net loss per day for a cow is 231€ on poorly managed farm; which is 305*231 is about 70,455€ annual loss per cow without including calf crop. 8 This is mainly depend on management, climatic stress and inadequate feed supply that affect prepubertal growth, consequently stunted heifers do not reach puberty at right time. 24,25 A similar finding of wide interval age at first calving observed in Hawassa and DebreBiran cities smallholder dairy farm. ...
... The average day's open in a good situation is 83(67-130) in a most standard dairy farm. 8 This study shows all parity group of the cow had above 142 days "day's open" which ranges from 56 to 818 days. The finding indicates very poor production performance. ...
Article
Study was conducted between November 2015 and March 2016 at Alagae dairy farm. The objective of study was to evaluate ten years record and the current status of dairy farm. A total of 370 cow’s record and 105 monitored dairy cows’ were used for the study. The overall mean months of 27.68±6.48 age at first service, 37.8±6.88 age at first calving, 16.36±5.2 calving interval, 6.93±4.79 days open (DO) and 10.32±2.84 lactation length (LL) observed. Increasingly, 1.38±0.54 number of services per conception (NSC) and average daily milk yield of 8.22±2.2 liters/day/cow were observed in the dairy farm. Average daily milk yield had a significant difference (p<0.05) between Holstein and their crosses. Reproductive performance did not show difference between retrospective and longitudinal studies using Mann Whitney U – test. Similar health problems like abortion, dystocia, metritis, repeat breeder, retained fetal membrane, mastitis and pre-weaning calf mortality observed in both retrospective and longitudinal studies cows. Physical damage and infectious diseases were also common in the farm. In conclusion, this study revealed that the reproductive performance of the dairy farm was below the acceptable standard. Therefore, appropriate measures should be implemented at Alagae dairy farm in order to leverage the existing poor reproductive performance of the farm.
... For this reason, it is of critical importance to investigate new possible management routines to allow for flexibility and thereby resilience, and to question old 'truths'. One of the practices that has been challenged in several studies over many years (Arbel et al. 2001;Gaillard et al. 2016;Römer et al. 2020;Burgers 2022) is that a cow should have one calf per year to be most profitable (Strandberg & Oltenacu, 1989;Inchaisri et al. 2011;Steeneveld & Hogeveen, 2012). ...
... However, the drawback is that results from one research herd may not be as generalizable as those in studies performed on multiple commercial herds. As shown in Figure 6, some studies have reported results for primiparous and multiparous cows separately (Schindler et al. 1991;Ratnayake et al. 1998;Arbel et al. 2001;Österman & Bertilsson, 2003;Burgers et al. 2021b). This makes the results more relevant for this thesis, as for some variables, such as persistency, there are differences between primiparous and multiparous cows. ...
... In Paper I, cows in the EXT treatment had lower milk yield at dry-off than cows in the CONV treatment. This was also the case on comparing the ExtExt and ExtConv treatments in Paper III, and is in line with findings by Arbel et al. (2001) and Niozas et al. (2019a). Compared with the ConvConv treatment, milk yield before dry-off in the ExtExt treatment did not differ ( Figure 13F), despite the ExtExt cows having a higher yield in early lactation, likely explained by their increased lactation length. ...
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Extension of the voluntary waiting period (VWP) before first insemination after calving, could decrease the frequency of demanding transition periods both at cow and herd level. In the initial study of this thesis, the cows were randomized to an extended (155-205 d) or conventional (35-85 d) VWP and assessed during their first and second lactation. In a later study on customized extended VWP, cows expected to be suited for extended VWP were selected based on high genomic persistency index, calving difficulties or disease in early lactation, and high early lactation yield, and then randomly allocated to extended (≥185) or conventional (≤90) VWP. For cows with randomized extended compared with conventional VWP, milk yield per day in the calving interval was maintained during the first lactation and higher during the second lactation, milk yield before dry-off was lower and reproductive performance was improved. Cows with customized extended VWP showed similar improvements compared with cows expected to be suited for an extended but receiving conventional VWP, but in contrast to the randomized study, the dry period was not longer for cows randomized to customized extended VWP. Extending the VWP had no effect on disease incidence and culling rate. Extended VWP for primiparous cows in high-yielding herds can thus make use of modern dairy cows’ great potential for milk production and fertility, thereby potentially increasing flexibility and resilience in dairy herds.
... Previous randomized studies of fertility measures in cows with extended VWP show conflicting results for NINS (Schneider et al., 1981;Niozas et al., 2019b;Burgers et al., 2022), FSCR (Arbel et al., 2001;Niozas et al., 2019b), and IPL (Schneider et al., 1981;Ratnayake et al., 1998;Niozas et al., 2019b); these results have mostly been reported for primi-and multiparous cows combined. The effect of extended VWP on health indicators show few conclusive results as well; however, Ma et al. (2022) found that cows with an extended VWP of 200 d had higher SCC in the beginning of the subsequent lactation than cows with a 50-d VWP. ...
... The effect of extended VWP on health indicators show few conclusive results as well; however, Ma et al. (2022) found that cows with an extended VWP of 200 d had higher SCC in the beginning of the subsequent lactation than cows with a 50-d VWP. Previous findings on the effects of VWP length on culling are also inconsistent, as Niozas et al. (2019a) reported higher overall culling and culling due to low productivity in cows with 180-d compared with 40-d VWP, whereas Burgers et al. (2022) and Arbel et al. (2001) did not detect any increased risk of culling in cows with extended VWP. In a study by Larsson and Berglund (2000), a smaller proportion of cows with extended VWP were culled due to low fertility. ...
... However, this gives the herd manager more time to gather information about the cows and their yield, potentially leading to better-informed decisions about culling. This theory, in combination with the possibility that the farmers may have had preconceptions that high-yielding cows may be better suited to extended VWP, based on results from previous studies (Arbel et al., 2001;Römer et al., 2020), was supported by our findings on milk yield per day during early lactation in cows not receiving their planned VWP treatment. From 4 to 33 DIM, we found no difference in average daily yield between the VWP treatments, indicating that at the start of intervention for the conventional VWP treatment, compliance did not depend on milk yield. ...
Article
When the voluntary waiting period (VWP), defined as the days between calving and when the cow is eligible to receive the first insemination, is extended, high-yielding dairy cows may have better opportunities to regain energy balance before first insemination. This study investigated the effect of an extended (145-215 DIM, n = 280) or conventional (25-95 DIM, n = 251) VWP treatment on fertility, disease incidence, and culling rate in cows during their first lactation. The cows were also followed through a second lactation without intervention regarding VWP, during which the farmers could decide when they wished to start the inseminations. This was done in a randomized-controlled study on 16 high-yielding commercial herds in southern Sweden containing a total of 531 primiparous cows of the Holstein (HOL) and Red Dairy Cattle (RDC) breeds. Data from the Swedish national dairy herd recording scheme (SNDRS) collected between August 2018 and September 2021 were used in the analysis, including records on breed, calvings, estrus intensity, inseminations, disease, somatic cell count (SCC), culling date, and culling reason. During first lactation, more cows receiving the extended VWP treatment showed strong estrus intensity (score 4-5, 55% vs. 48%), and fewer showed moderate estrus intensity (score 3, 35% vs. 43%), at first insemination, compared with cows receiving the conventional VWP treatment. First service conception rate (FSCR) was higher (67% vs. 51%) and number of inseminations per conception (NINS) was lower (1.6 vs. 2.0), during the first lactation, for cows receiving the extended compared with the conventional VWP treatment. For disease incidence rate or culling rate expressed as number of events per cow-time in the study, there were no differences between the cows receiving the 2 VWP treatments in any lactation. Calving to first service interval (CFI) during second lactation was longer (86 vs. 74 d) for cows with extended compared with conventional VWP. In conclusion, primiparous cows with extended VWP showed improved reproductive functions, in the form of higher estrus intensity, higher FSCR, and lower NINS, during the first lactation. However, there was no apparent effect on these fertility measures during the following lactation (without VWP intervention), and no differences in disease prevalence or culling between cows receiving the 2 VWP treatments in either lactation. Compliance with the planned VWP treatment was lower for cows with planned extended compared with planned conventional VWP treatment. We studied the "intention-to-treat" effect, i.e the results for all cows randomized to each treatment regardless of whether the planned VWP was achieved or not, to identify any bias arising due to degree of compliance. However, we found no difference in culling rate between cows randomized to an extended VWP compared with those randomized to a conventional VWP. These findings can be used to support management decisions on VWP length in high-yielding dairy herds.
... The effect of voluntary waiting period (VWP), defined as the period between calving and when the cow is permitted to receive the first insemination, on milk production and economics has been examined in several previous studies but with inconclusive results. Randomized controlled studies have generally found extended VWP to be more economically favorable relative to conventional VWP (Arbel et al., 2001;Burgers et al., 2021a), than previous simulation studies (Strandberg and Oltenacu, 1989), simulation studies based on data from voluntary extension of the VWP , and studies based on retrospective data (Holmann et al., 1984;Inchaisri et al., 2011). Since the time of those studies, average yearly milk yield (MY) of dairy cows has increased dramatically. ...
... Planned extended VWP has been shown not to affect milk production per CInt day during the first lactation (Österman and Bertilsson, 2003;Niozas et al., 2019a;Burgers et al., 2021a) or to increase it (Arbel et al., 2001). Milk yield during early lactation after a previous lactation with extended VWP is reported to be higher (Arbel et al., 2001;Lehmann et al., 2016) or similar (Burgers et al., 2021a) to that after a previous lactation with conventional VWP. ...
... Planned extended VWP has been shown not to affect milk production per CInt day during the first lactation (Österman and Bertilsson, 2003;Niozas et al., 2019a;Burgers et al., 2021a) or to increase it (Arbel et al., 2001). Milk yield during early lactation after a previous lactation with extended VWP is reported to be higher (Arbel et al., 2001;Lehmann et al., 2016) or similar (Burgers et al., 2021a) to that after a previous lactation with conventional VWP. In a 3-yr study, Österman and Bertilsson (2003) monitored 1 group of cows with 3 consecutive 12-mo CInt and another group with 2 con-secutive 18-mo CInt and found no difference between the groups in ECM yield per day of CInt during the second lactation. ...
Article
Extending the voluntary waiting period (VWP) for primiparous cows can have a positive impact on fertility without a negative impact on milk production per day in the calving interval (CInt). We investigated the effect of extended VWP during first lactation on milk yield (MY) during 2 consecutive lactations in primiparous cows. The study involved 16 commercial herds in southern Sweden. A total of 533 Holstein and Red dairy cattle (Swedish Red, Danish Red, Ayrshire) dairy cows were randomly assigned to a conventional 25 to 95 d VWP (n = 252) or extended 145 to 215 d VWP (n = 281). Data on calvings, inseminations, and test-day yields were retrieved from the Swedish Milk Recording System. Cows with VWP according to plan and completing 1 or 2 CInt with a second or third calving were included in the data analysis. Whole lactation and 305-d energy-corrected milk (ECM) yield were higher for the extended VWP group than the conventional VWP group in both the first lactation (12,307 vs. 9,587 and 9,653 vs. 9,127 kg ECM) and second lactation (12,817 vs. 11,986 and 11,957 vs. 11,304 kg ECM). We found no difference between the VWP groups in MY per day during the first CInt or during the first and second CInt combined, although MY per day during the second CInt was around 1.5 kg higher for cows with extended VWP than for cows with conventional VWP. Thus extended VWP for primiparous cows can be used as a management tool without compromising MY.
... It is the interval between date of calving and date of successful conception. It is one of the best indicator variables, which is most commonly used to measure fertility performance in dairy cattle [23]. Days open directly affect CI, which plays a vital role in the achievement of dairy farms. ...
... Number of service per conception has been defined as the number of services required for a successful conception [23]. The number service per conception depends largely on the breeding system used. ...
... Breeding failure has a clear negative influence on milk production and farm income and determines the future sustainability of a dairy farming operation. Milk production level and lactation persistency are crucial factors determining the appropriate calving interval [23]. ...
... Ratnayake et al. (1998) also reported fewer days from first insemination to pregnancy by extending the VWP from 150 days to 240 days. Other studies, however, found no difference in days until pregnancy after the end of the VWP between a conventional versus extended VWP (Schindler et al., 1991;Arbel et al., 2001). ...
... In addition, in these modeling studies the economic consequences were based on milk yield data and it was unknown what the reasons were that cows had an extended lactation, e.g., if it was a deliberate choice by the farmer or that it was due to impaired health or fertility of the cow. More recently, some studies reported the economic result of a deliberately extended VWP (Arbel et al., 2001;Stangaferro et al., 2018;Burgers et al., 2022), including besides milk yield data, also other variables including veterinary costs, culling rate, labor and benefits and costs for calf rearing. In the study of Arbel et al. (2001), yearly net return increased by $0.19 per day of calving interval for primiparous cows when the VWP was extended from 93 to 154 d, and increased with $0.12 per day per calving interval for multiparous cows with extended VWP from 71 to 124 d, only high-producing cows were included in this study. ...
... More recently, some studies reported the economic result of a deliberately extended VWP (Arbel et al., 2001;Stangaferro et al., 2018;Burgers et al., 2022), including besides milk yield data, also other variables including veterinary costs, culling rate, labor and benefits and costs for calf rearing. In the study of Arbel et al. (2001), yearly net return increased by $0.19 per day of calving interval for primiparous cows when the VWP was extended from 93 to 154 d, and increased with $0.12 per day per calving interval for multiparous cows with extended VWP from 71 to 124 d, only high-producing cows were included in this study. In another study, when extending VWP from 60 to 88 d, the yearly cashflow was numerically increased for primiparous cows and numerically decreased for multiparous cows (Stangaferro et al., 2018). ...
Article
The aim of the study was to evaluate the effect of extended voluntary waiting period (VWP) on ovarian cyclicity and reproductive performance of dairy cows. Holstein-Friesian dairy cows (N=154) were blocked and randomly assigned to one of 3 groups with different VWP (50, 125 or 200 d: VWP-50, VWP-125 or VWP-200). Milk samples were collected 3 times a week and analysed for progesterone concentration. Ovarian cycles were classified as: normal (18 to 24 days), short (<18 days) or prolonged (>24 days). For cows that became pregnant within 100 days after VWP, a VWP-200 d was related with fewer days until pregnancy after end of the VWP (19.4 d) compared with VWP-50 or VWP-125 (35.5, 37.3 d respectively). During 100 days (-50 until 50 d) around the end of VWP, cows in VWP-200 had a greater percentage of normal cycles (91.9 vs 58.0%, P <0.01) and a lower percentage of prolonged cycles (6.0 vs 32.7%, P =0.01) compared with cows in VWP-50. In the 4 weeks around the end of the VWP, cows in VWP-125 and VWP-200 had a lower milk yield compared with cows in VWP-50 (32.0, 27.5 vs 37.4 kg/d, P<0.01). Inseminations continued until 300 days in milk, resulting in fewer pregnant cows for longer VWPs. In conclusion, extending the VWP from 50 to 125 or 200 days resulted in a greater percentage of cows with normal ovarian cycles and a lower milk yield around the end of VWP. Moreover, VWP-200 reduced days open after the end of the VWP, compared with VWP-50.
... Extending the VWP results in longer lactation lengths and calving intervals (Van Amburgh et al., 1997;Rehn et al., 2000;Arbel et al., 2001;Österman and Bertilsson, 2003;Stangaferro et al., 2018a, b;Niozas et al., 2019a;Burgers et al., 2021b). Longer lactations prolong the period of late lactation, where milk production is generally lower, yet increase the number of lactating days relative to dry days. ...
... In most of the reviewed studies, a longer VWP resulted in a lower MY/CI for multiparous cows, and [a higher MY/ CI] for primiparous cows (Figure 2), while in several studies VWP length had no significant effect (Rehn et al., 2000;Arbel et al., 2001;Österman and Bertilsson, 2003). Within multiparous cows, yield of cows with a VWP of 200 d was lower than that of cows with a VWP of 50 d when expressed as fat-and-protein-corrected milk per day of calving interval (Burgers et al., 2021b), and within primiparous cows, yield of cows with a VWP of 150 d was higher than that of cows with a VWP of 90 d when expressed as value-corrected milk per day of calving interval (Arbel et al., 2001). ...
... In most of the reviewed studies, a longer VWP resulted in a lower MY/CI for multiparous cows, and [a higher MY/ CI] for primiparous cows (Figure 2), while in several studies VWP length had no significant effect (Rehn et al., 2000;Arbel et al., 2001;Österman and Bertilsson, 2003). Within multiparous cows, yield of cows with a VWP of 200 d was lower than that of cows with a VWP of 50 d when expressed as fat-and-protein-corrected milk per day of calving interval (Burgers et al., 2021b), and within primiparous cows, yield of cows with a VWP of 150 d was higher than that of cows with a VWP of 90 d when expressed as value-corrected milk per day of calving interval (Arbel et al., 2001). Niozas et al. (2019b) found a similar production per day in lactation for cows with a VWP of 40, 120, or 180 d, with an increase in lactation length of 106 d and an increase in dry period length of 10 d for a VWP of 180 d, also implying that MY/CI was not affected. ...
Article
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Traditionally, a 1-year calving interval is advised to farmers from an economical point of view, to realize a yearly peak in milk yield. A 1-year calving interval, however, implies a yearly event of drying-off, calving and start of lactation, which are all associated with an increased risk for diseases and disorders. Deliberately extending the lactation length by extending the voluntary waiting period for first insemination (VWP) reduces the frequency of these challenging events. This reduction in frequency of calvings can be beneficial for cow health and fertility, but also can be of interest to reduce the number of surplus calves and labor associated with drying off, calving and disease treatments. Current concerns with respect to an extended lactation are that milk yield is too low in late lactation, which might be associated with an increased risk of fattening of cows in late lactation, and compromised economic returns at herd level. In addition, limited knowledge is available with respect to consequences for cow performance in the subsequent lactation and for calves born to cows with an extended lactation. Moreover, response of dairy cows to an extended VWP depend on individual cow characteristics like parity, milk yield level or body condition. A customized strategy based on individual cow characteristics can be a future approach to select high-producing cows with persistent lactation curves for an extended lactation to limit the risk for fattening and milk yield reduction at the end of the lactation while benefitting from a reduction in challenging events around calving.
... The CInt has been deliberately extended in experimental studies (Rehn et al., 2000;Arbel et al., 2001;Niozas et al., 2019) and on commercial farms (Lehmann et al., 2016). When CInt was extended from 368 to 430 d for both primiparous and multiparous cows, milk yield and ECM per day of CInt did not differ (Rehn et al., 2000). ...
... Parity could affect the results for milk yield of cows after different VWP. When extending CInt for primiparous cows, milk and ECM yield per day of CInt increased, whereas for multiparous cows, yield stayed the same (Arbel et al., 2001;Lehmann et al., 2016) or decreased (Österman and Bertilsson, 2003). Differences among parities concerning consequences of an extended VWP on milk yield could be related to more persistent lactations for primiparous cows compared with multiparous cows (Niozas et al., 2019). ...
... Primiparous cows seem to be appropriate to select for an extended VWP, without losing milk. This is comparable to other studies, where primiparous cows kept for extended lactations achieved similar or even greater lactation yields compared with primiparous cows in shorter lactations (Arbel et al., 2001;Lehmann et al., 2016). The main reason that primiparous cows achieve the same yield per day of CInt after an extended VWP as after a short VWP of 50 d is their high lactation persistency (Arbel et al., 2001;Lehmann et al., 2016;Niozas et al., 2019). ...
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A 1-yr calving interval (CInt) is usually associated with maximized milk output, due to the calving-related peak in milk yield. Extending CInt could benefit cow health and production efficiency due to fewer transition periods per unit of time. Extending CInt can affect lactation performance by fewer days dry per year, delayed pregnancy effect on milk yield, and greater milk solid yield in late lactation. This study first investigated the effects of 3 different voluntary waiting periods (VWP) from calving until first insemination on body weight, body condition, milk yield, and lactation persistency. Second, individual cow characteristics in early lactation were identified that contributed to milk yield and persistency of cows with different VWP. Holstein-Friesian dairy cows (n = 154) within 1 herd were blocked for parity, calving season, and expected milk yield. Cows were randomly assigned within the blocks to 1 of 3 VWP (50, 125, or 200 d: VWP50, VWP125, or VWP200, respectively) and monitored through 1 complete lactation and the first 6 wk of the subsequent lactation, or until culling. Minimum and mean CInt (384 vs. 452 vs. 501 d for VWP50 vs. VWP125 vs. VWP200) increased with increasing VWP, but maximum CInt was equal for the 3 VWP. Fat- and protein-corrected milk yield (FPCM) was analyzed weekly. Milk yield and FPCM were also expressed per day of CInt, to compare yields of cows with different VWP. Persistency was determined between d 100 and d 200 of the lactation, as well as between d 100 and dry-off. Values are presented as least squares means ± standard error of the mean. During the first 44 wk of lactation, VWP did not affect FPCM yield in both primiparous and multiparous cows. The VWP did not affect milk yield per day of CInt. The VWP did not affect FPCM yield per day of calving interval for primiparous cows. Multiparous cows in VWP125 had FPCM yield per day of CInt similar to that of VWP50. Multiparous cows in VWP200 had lower FPCM yield per day of CInt compared with VWP50 (27.2 vs. 30.4 kg/d). During the last 6 wk before dry-off, cows in VWP125 had lower yield compared with cows in VWP50, which could benefit their udder health in the dry period and after calving. Persistency was better for cows in VWP200 compared with cows in VWP50 (−0.05 vs. −0.07 kg/d). Body weight was not different among VWP groups. Multiparous cows in VWP200 had a higher body condition score in the last 3 mo before dry-off and the first 6 wk of the next lactation, compared with multiparous cows in VWP125 and VWP50. The VWP could be extended from 50 d to 125 d without an effect on daily yield per day of calving interval. Extending VWP until 200 d for primiparous cows did not affect their daily milk yield, but multiparous cows with a 200-d VWP had a reduced milk yield per day of calving interval and an increased body condition in late lactation and the subsequent lactation, compared with multiparous cows with a 50-d VWP.
... Research is so far inconclusive what strategy results in higher milk output -while most studies agree that longer lactation results in higher total lactation MY for primiparous cows, the results diverge whether it also leads to higher MY per day of CI (MY CI , including lactation and dry period). Some studies (Arbel et al. 2001;Mellado et al. 2016) indicated that for primiparous cows in herds with high milk yield (over 10 000 kg for 305-day lactation), longer calving intervals were associated with higher, not lower MY CI . The others (Stangaferro et al. 2018) have not observed any difference in MY CI . ...
... The purpose of the study was to empirically analyse the relationship between CI and MY in Estonian high-yielding herds. Given the limited resources available for dairy farmers -is minimizing CI 1 a justified management objective in the context of ever higher milk yield per day in milk and shorter productive life, as several studies (Rehn et al. 2000;Arbel et al. 2001) suggest otherwise. ...
... Lactation persistency and MY PEAK were hypothesised to be associated with conception timing. 21.5% (Arbel et al. 2001). In these studies, though, deliberate extension of CIs was used for all or selected animals in all sample herds, which was not the case on the farms in our study. ...
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Data about 4 474 high-yielding Estonian Holstein dairy cows from 14 herds was analysed for the impact of the first calving interval length (CI1) on milk yield (MY) and lactation persistency. The results show that cows with CI1 shorter than 12 months have on average 2 345 kg lower milk yield in the first 1 000 days of productive lifetime than those with CI1 between 14 and 16 months. This is caused by lower MY in both the first and the second lactation as well as higher probability of being culled before reaching 1 000 days of productive life.
... У більшості розглянутих досліджень довша тривалість добровільного сервіс-періоду призводила до нижчого добового надою на один день міжотельного періоду (Stangaferro et al., 2018;Burgers et al., 2021), тоді як у кількох дослідженнях довжина аналогічного сервісперіоду не мала істотного впливу на цей показник (Rehn et al., 2000;Arbel et al., 2001;Österman & Bertilsson, 2003). У корів з багаторазовими отеленнями продуктивність корів з сервіс-періодом 200 днів була нижчою, ніж у корів з його тривалістю 50 днів (Burgers et al., 2021). ...
... У цьому ж аспекті автори (Niozas et al., 2019) вважають, що подовжена лактація, яка реалізується насамперед через довший сервіс-період, природно зменшить кількість надлишкових телят, народжених на корову на рік, а подовження сервіс-періоду для високопродуктивних корів до 120 днів не буде мати несприятливих наслідків щодо виробництва молока, вимушеного вибракування, здоров'я вимені або покращення екстер'єру. Тобто, розширений добровільний сервіс-період є більш економічно вигідним порівняно зі звичайним (Arbel et al., 2001;Burgers et al., 2021). ...
Article
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Impact research of the duration of service period on the longevity traits of Holstein and Ukrainian Black-and-White dairy cows was conducted in the herd of private enterprise "Burynske" in Sumy district. It has been established that the milk yield of cows for 305 days and full lactation according to the assessment data of the first, third and best lactations and, in general, for the entire life, grew under the condition of increasing the duration of service period to the level of 140 days, regardless of breed. A further increase in the duration of service period for 141 days led to a decline in the above-mentioned traits. The highest lifetime milk yield was obtained from a group of cows with a service period length of 121–140 days, which amounted to 31955 ± 606.7 kg in Holsteins, and 30188 ± 624.4 kg for Ukrainian Black-and-White dairy breed. Against the background of increase in the duration of service period, rising rates of lifetime, productive use and the number of used lactations was observed in cows of experimental breeds. However, the yield per day of life and productive use decreased in groups of Holstein breed with a service period of ˃ 80–161 < days, from 14.6 to 10.3 kg and from 24.7 to 14.6 kg, respectively. In the groups of cows of the Ukrainian Black-and-White dairy breed with the duration of service period ˃ 80–161 < days, corresponding reduction in milk yield per day of life and productive use amounted to 13.1–9.5 and 21.9–13.2 kg. A direct, medium-level, reliable relationship between the service period length and the traits of lifetime, productive use, milk yield and milk fat during life was revealed, which was within the range of r = 0.193–0.311 in Holstein cows and Ukrainian Black-and-White dairy r = 0.145–0.251. An inverse and highly reliable relationship was found between the duration of service period and the milk yield per day of life and productive use in Holstein cows (r = -0.268 and -0.383) and Ukrainian Black-and-White dairy breed (r = -0.255 and -0.325). The strength of influence the duration of service period of cows on their lifespan, productive use and number of used lactations was 22.4–27.5% for Holstein breed, and 21.4–24.3% for Ukrainian Black-and-White dairy breed. Traits of lifetime milk productivity of Holstein cows depended on the duration of service period by 12.2–31.3% and of Ukrainian Black-and-White dairy cows by 13.4–28.9%.
... Primiparous cows, however, have greater lactation persistency than multiparous cows (Burgers et al. 2021a). As a consequence, extending the VWP for primiparous cows had no effect on milk yield per day of CI (Rehn et al. 2000), or increased milk yield per day of CI in other studies (Arbel et al. 2001;Stangaferro et al. 2018b). ...
... Cows with an extended VWP in some studies had higher conception rates at first AI, and fewer days open after the end of the VWP; though other studies found no effect of VWP on these variables. Differences among studies could be related to (1) Parity of the cows, with no improvement of reproductive performance in primiparous cows (Arbel et al. 2001); (2) Differences in management protocol, i.e., days open after end of the VWP was not reduced when cows were insemination after an estrous synchronization protocol (Stangaferro et al. 2018b) or lactations were managed with use of bovine somatotropin to stimulate milk production (Van Amburgh et al. 1997) or (3) Extent of the VWP contrast and consequences of the VWP extension for body condition. ...
Chapter
Extending lactation length, as well as shortening or omitting the dry period have interesting perspectives on health and fertility of high-producing dairy cows. By extending lactation length, the frequency of critical calving events for the cow reduces, herewith reducing the frequency of periods with increased risk for health problems. Alternatively, shortening or omitting the dry period reduces the number and magnitude of peripartum transitions for the cow, with less milk and a better energy balance after calving. Potential risks of these management strategies are that milk yield of cows at the end of lactation is too low to extend the lactation period, and that cows fatten in late lactation. Therefore, both extending lactation length and shortening or omitting of the dry period might not fit every cow. Individual cow characteristics like parity, milk yield level, body condition, or health status contribute to the response of the cow to an extended lactation or shortened or omitted dry period. These individual cow characteristics can be used in customized management strategies to optimize lactation length or dry period length for individual cows. Customized lactation or dry period length could limit the impact at herd level of disadvantages concerning milk losses and body fattening and maintain benefits for improved cow health and fertility, reduced number of surplus calves, and increased work satisfaction for the farmer.
... Moreover, Allendorf and Wettemann (2015) found that a long calving interval decreases technical efficiency. However, in very high yielding cows, longer calving intervals may be economically beneficial (Arbel R et al., 2001). Calves (Fig. 2) include animals from birth to six months of age, and measures number of dead calves and calves treated by veterinarians, factors which are likely to reduce profits and efficiency. ...
... Thus, a low Fertility indicator due to a long calving interval does not necessarily imply bad animal welfare but may instead be due to poor fertility management. Moreover, under certain circumstances a long calving interval may even be economically beneficial (Arbel et al., 2001). Thus, our indicators aim to capture both the level of animal welfare and the level of management in terms of productivity and economy. ...
... Many studies have been conducted on the effect of lactation number on milk yield in cows. In many of these studies, it was stated that milk production increased with the number of lactations and peaked in the fourth or fifth lactation [12][13][14]. It is reported that the reason for this situation is due to the increase in the number of secretory cells owing to the increased development and size of the udder [15,16]. ...
... In terms of the relationship between lactation number and total milk yield and 305-d milk yield values, the results were similar to those of many other studies in the literature [7,32,35,36]. In many of the studies, it was stated that milk production increased with the number of lactations and peaked in the fourth or fifth lactation [12][13][14]. It is reported that the reason for this situation is due to the increase in the number of secretory cells owing to the increased development and size of the udder [15,16]. ...
Article
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This study was intended to determine whether there was any difference between the parameters of herd size and milk yield based on the hypothesis that the dairy cattle enterprises in the Teke Region used different production methods depending on their herd size. Total milk yield and 305-d milk yield were increased in parallel with the farm-scale and reached 8968.70 ± 124.56 kg and 7632.20 ± 79.67 kg, respectively, in the farms with the largest scale of 101 heads and above (p < 0.001). It was further determined that milk yield decreased significantly in the summer calving season compared to other seasons (Summer: 7897.20 ± 154.48 b, Autumn: 8344.80 ± 169.33 a, Winter: 8054.50 ± 127.22 a, Spring: 8133.60 ± 159.77 a) (p < 0.01). Heat stress is thought to be the reason for the low milk yield in the summer season compared to other seasons. It was shown that the small-scale farms with 1–10 cows had the longest lactation length (394.90 ± 6.90 days) (p < 0.001). It was also determined that there is a directly proportional and significant relationship between the lactation number of Holstein cattle and lactation milk yield and 305-d milk yield values (p < 0.01). It was determined that dairy cattle in the 5th lactation had the highest 305-d milk yield value with 6992.00 ± 164.40 kg. In conclusion, a positive statistical correlation was found between the scale of dairy farms and their milk production parameter.
... Another strategy is to delay the insemination day to a period during which the energy balance is back to positive (which is usually not the case for the typical 10 mo of lactation). This delay of rebreeding leads to an extended lactation that appears to be more advantageous, in terms of daily milk yield and economic profitability, for primiparous cows compared with multiparous cows (Arbel et al., 2001;Osterman and Bertilsson, 2003;Gaillard et al., 2016). This is probably partly due to the higher persistency of primiparous cows than multiparous, helping them maintain good milk production at the end of lactation. ...
... This is probably partly due to the higher persistency of primiparous cows than multiparous, helping them maintain good milk production at the end of lactation. Regarding pregnancy rates, in most cases, no significant difference was found between cows in extended lactation and cows in a normal 10-mo lactation (Arbel et al., 2001;Gaillard et al., 2016). ...
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Modern animal scientists, industry, and managers have never faced a more complex world. Precision livestock technologies have altered management in confined operations to meet production, environmental, and consumer goals. Applications of precision technologies have been limited in extensive systems such as rangelands due to lack of infrastructure, electrical power, communication, and durability. However, advancements in technology have helped to overcome many of these challenges. Investment in precision technologies is growing within the livestock sector, requiring the need to assess opportunities and challenges associated with implementation to enhance livestock production systems. In this review, precision livestock farming and digital livestock farming are explained in the context of a logical and iterative five-step process to successfully integrate precision livestock measurement and management tools, emphasizing the need for precision system models (PSM). This five-step process acts as a guide to realize anticipated benefits from precision technologies and avoid unintended consequences. Consequently, the synthesis of precision livestock and modeling examples and key case studies help highlight past challenges and current opportunities within confined and extensive systems. Successfully developing PSM requires appropriate model(s) selection that aligns with desired management goals and precision technology capabilities. Therefore, it is imperative to consider the entire system to ensure that precision technology integration achieves desired goals, while remaining economically and managerially sustainable. Achieving long-term success using precision technology requires the next generation of animal scientists to obtain additional skills to keep up with the rapid pace of technology innovation. Building workforce capacity and synergistic relationships between research, industry, and managers will be critical. As the process of precision technology adoption continues in, more challenging and harsh, extensive systems it is likely that confined operations will benefit from required advances in precision technology and PSM, ultimately strengthening the benefits from precision technology to achieve short-and long-term goals.
... In this poor fertility scenario, extending the calving interval not necessarily negatively influences economic returns of the dairy operations (Groenendaal et al. 2004;Inchaisri et al. 2011). On the contrary, extended calving intervals of highyielding cows could have economic advantages and allows the farmer an option for decisions regarding individual cows (Arbel et al. 2001). Additionally, planned EL in intensive dairy herds may improve herd efficiency, health, longevity, and welfare of cows and herd profitability (Lehmann et al. 2019). ...
... Twelve to 13 months calving interval have been a general recommendation for maximizing dairy herd profitability (Hansson and Óhlmér 2008;Dono et al. 2013); however, the present study has justified longer calving intervals for subfertile high-producing cows based on increased milk yield per lactation due to the lessened effect of pregnancy on milk yield in cows with excessive days open (Penasa et al. 2016). Other studies have demonstrated that a delay of first insemination post-calving compared to the usual voluntary waiting period of highyielding cows has economic advantages (Arbel et al. 2001;Lehmann et al. 2016;Stangaferro et al. 2018). Services per pregnancy were affected by number of extended lactations (P < 0.01), being lowest for cows with no extended lactations and highest in cows with five successive EL (Table 1). ...
Article
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A total of 1338 high-yielding cows with five lactations from a large well-managed commercial dairy operation in a hot environment of northern Mexico were used to evaluate milk yield and reproductive performance of cows undergoing unplanned extended lactations (EL; > 450 days). The null hypothesis that cumulative milk yield during five consecutive lactations is the same in cows not having unplanned EL and cows with several EL was tested. All EL resulted from cows failing to become pregnant with ≥ 4 services. Cows were allocated to 1 of 6 groups according to the number of EL (EL0 for cows with no EL to EL5 for cows with 5 EL). Cumulative milk yield was highest (P < 0.01) for EL5 cows (95,499 kg) and lowest for EL0 cows (56,236 kg). Likewise, cumulative days in milk were greatest (P < 0.01) in EL5 (2968 days) and lowest in EL0 (1857 days) cows. Mean milk yield per lactation increased linearly with the increase in the number of extended lactations with a maximum of 19,099 kg of milk/lactation for EL5 cows. Mean daily milk yield/productive life was lowest (P < 0.01) for EL0 (30.2 kg) and highest for EL5 (32.1 kg). The percentage of days in milk relative to days from birth to the end of the fifth lactation was highest for EL5 (78.1%) and lowest for EL0 (59.6%), with EL2 to EL4 cows intermediate. Length of calving interval was longest (P < 0.01) for EL5 (24.7 months) and shortest for EL0 (15.5 months) cows. It was concluded that it is worthwhile maintaining high-yielding cows incapable to conceive before 230 days in milk because they did conceive again and produced considerable amounts of milk during their productive life, which substantially prolonged their permanence time in the herd.
... ,Chakraborty et al. (2010) andPatil et al. (2018) but lower values were reported byKumar et al. (2000) andSuresh et al. (2004), however, higher estimates ranging from 13.7 to 26.4 kg/day were obtained byArbel et al. (2001) andZambianchi et al. (1997) in Holstein cows. The heritability estimates of the production efficiency traits viz. ...
Article
The study employed data collected from 662 Murrah buffaloes meticulously documented over a 24-year period (1996-2019). The data were sourced from historical pedigree records maintained at the buffalo farm of the Department of Livestock Production and Management (LPM) at Lala Lajpat Rai University of Veterinary and Animal Sciences in Hisar. The average values under univariate animal model for production efficiency traits viz. MCI and MSC were 4.84 kg/day and 1.33 kg/day, respectively. Six univariate animal models were utilized to compute (co)variance components and heritabilities for traits related to first lactation production efficiency. Among these models, Model 1 was identified as the most suitable for calculating milk yield per day of calving interval (MCI), while Model 2 proved optimal for milk yield per day of age at second calving (MSC). Maternal effects were observed to influence MSC (ranging from 0.09 to 0.22). The heritability estimates for the production efficiency traits, namely MCI and MSC, were 0.35±0.12 and 0.15±0.09, respectively. The breeding values for production efficiency traits ranged from 0.46kg/day for MCI to 0.63 kg/day for MSC. A significant and positive genetic correlation between additive and maternal effects was identified, ranging from 0.41 to 0.98. This suggests a consistent and strong interaction between genetic factors inherited from the dam. Rank correlation of breeding values across all six models ranged from 0.71 (non-significant) to 1.00 for MCI and MSC.MCI exhibited positive genetic and phenotypic trends, showing annual increases of 0.009±0.005 kg/day and 0.148±0.018 kg/day, respectively. In contrast, MSC displayed a very low negative genetic trend (-0.001±0.001 kg/day), while a positive phenotypic trend was observed at 0.047±0.006 kg/day per year. These trends indicate that both selection and management practices are concurrently contributing to the improvement of production efficiency traits.
... Statistical data indicate that the fertilization rate of cows is 85~95%, while the birth rate of fetuses is only 30~50% [1,2]. Reproductive issues in cows result in extended calving intervals and hinder reproductive efficiency, which ultimately leads to significant economic losses [3,4]. Addressing reproductive issues in cows occupies a central position within the field of bovine research, and a multitude of studies have been undertaken in this area in the past [5][6][7]. ...
Article
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Pregnancy failure in the first trimester of cows significantly impacts the efficiency of the dairy industry. As a type I interferon exclusively to ruminants, IFN-τ plays a key role in maternal recognition and immune tolerance of fetuses. Macrophages are the most common immune cells within the ruminant endometrium. Nevertheless, deeply analyzing the mechanisms of IFN-τ regulating macrophage polarization still needs further study. In this study, a notable decline of bta-miR-30b-5p expression via the increase of SOCS1 was observed in uterine tissues of pregnant cows. We then confirmed that the 3′UTR of SOCS1 was to be directly targeted by bta-miR-30b-5p. After that, we demonstrated that this obviously promoted the bovine macrophages (BoMac) polarized to M2 through enhancing SOCS1 expression with the treatment of IFN-τ. Furthermore, we found that SOCS1 restrained the expression of the key proteins p65 and p-P65 in the NF-κB pathway. Causing, the wide range of cross-species activities of IFN-τ, therefore we established a pregnant mouse model for the future confirmation of the above mechanism. The results verified that IFN-τ significantly improved this mechanism and maintained normal pregnancy status in mice, but miR-30b-5p significantly reduced the M2 polarization by inhibiting SOCS1, which activated the NF-κB signaling pathway, and then leading to the failure of embryo implantation. All these results indicated that IFN-τ can regulate immune tolerance during pregnancy by promoting M2 macrophage polarization through inhibiting bta-miR-30b-5p targeting SOCS1 to deactivate the NF-κB signaling pathway.
... Reproductive performance and milk yield are the two determining factors on profitability of a dairy farm (Arbel et al. 2001). During the last decades, however, the reproductive efficiency of dairy cattle have significantly been declined because of changes in the management and environment of commercial dairy farms and genetic selection for milk production (Lucy 2001;Weigel 2006;DeJarnette et al. 2007). ...
Article
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Background Voluntary waiting period (VWP), housing systems and the presence of a veterinarian are effective factors on reproductive performance of a dairy farm. Objectives This study aimed to investigate the management practices associated with VWP and its effects on reproductive performance. Methods A total of 136,943 records of 21,756 cows that calved between 1990 and 2013 were used. A questionnaire was also conducted with the farms involved to determine if they adjust the timing of insemination based on the body condition score (BCS) of the cows, postpartum health situation (PPHS) or environmental factors such as heat stress and season. The impact of changing the VWP selectively, the presence of a veterinarian and the type of barn on reproductive outcomes like days open (DO), number of services per conception (NSPC) and days to first service (DFS) was examined using a linear mixed model. This model considered animals and herds as random factors and management practices as fixed factors in the analysis. Results Among herds that reported altering the VWP based on heat stress, DFS significantly increased (61.68 ± 0.68 vs. 58.4 ± 0.83) while DO (119.70 ± 1.86 vs. 126.9 ± 2.29) and NSPC (1.98 ± 0.04 vs. 2.48 ± 0.05) reduced compared to herds that did not alter the VWP. Our results showed that farms with a full‐time veterinarian had a better reproductive performance than those with part‐time care (p < 0.05). Housing system was significantly associated with fertility traits, so that cows in free‐stall barns were more fertile than those kept in open‐shed barns. Conclusions The obtained results from this study indicated that management decisions to selectively altering the VWP led to difference in DFS and improved reproductive performance.
... (Singh et al.1986). Another important reproductive trait is days open (DO), and it is interval between date of calving and date of conception (Arbel et al. 2001). Days open directly affect calving interval (CI), which plays an important role in the profitability of dairy farms (Amene et al.2011 andNoakes et al.2001). ...
Article
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The present study was undertaken to evaluate the effect of non-genetic factors such as the period of calving, season of calving, and parity on economically important productive and reproductive traits in crossbred cows (Holstein Friesian × Sahiwal) maintained at livestock experiment station Qadirabad Sahiwal, Pakistan. The study ranged from 1995 to 2014 (20 years). The duration of 20 years was divided into 4 periods (P1, P2, P3, and P4) with each period consisting of five years. Each year was further divided into three seasons winter (November-February), summer (March- June), and spring (July-October) based on geo-climatic conditions prevailing in the region. The parameters used as indicators of reproductive performance in this study were age at first calving (AFC), days open (DO), dry period (DP) and calving interval (CI). The overall least squares mean and standard errors for these reproductive parameters were 1235.23±45.81, 202.08±6.75, 178.4±6.85 and 482±5.97 days, respectively. While productive parameters were lactation milk yield 305 d(LMY), daily milk yield, and Lactation length (LL), and the least squares mean and standard errors of these were 2471.44±78.44 kg,8.07±0.27kg and306.22±4.84 days, respectively. Twenty years (20) data of 641 lactation records of crossbred cows representing the variance analyses indicated that significant (P≤0.05) effect of season of calving on age at first calving (AFC), days open (DO), lactation length (LL), and lactation milk yield (LMY). Least-squares means illustrated that the period of calving also significantly (P≤0.00) affects lactation milk yield (LMY) lactation length (LL) and dry period (DP). Similarly, a significant (P≤0.00) effect of parity on lactation milk yield (LMY), dry period (DP), days open (DO), and calving interval (CI) was noted. It is therefore concluded that the reproductive and productive performance of these crossbred cows is affected by some non-genetic factors and breeders must consider the season of calving, period of calving and parity in the management program because they greatly affect the farm productivity and profitability and they must select animals with higher breeding values to be the parent of the next generation.
... The lactation performance of dairy cattle is usually measured by determining the total milk yield, lactation length, lactation persistency, milk lifetime production and herd life or longevity [3]. Milk production level and lactation persistency are crucial factors determining the appropriate calving interval [4]. In most modern dairy farms, a lactation length of 305 days is commonly accepted as a standard lactation length, but might not work for small holder dairy cows in which the lactation length is extended considerably in most cases [5,6,7]. ...
... It has also been shown that increasing the calving interval to 18 months can have a positive effect on reproductive indicators by reducing the need to treat ovarian abnormalities and increasing conception rates. The results of Arbel et al. [45] suggest that a longer calving interval is preferable for primiparous cows than for multiparous cows. According to García et al. [46], infertile insemination was 3.9 times higher in cows inseminated in the warmer months (May to September) than in those inseminated in the cooler months (October to April). ...
Article
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One of the most important decisions in dairy cattle production today is the correct choice of culling time for cows. In the culling decision process, the farmer has to take into account a number of factors, the complexity of which makes the decision-making task difficult. A crucial factor is the evolution of reproductive indicators. The aim of the research was to develop a microsimulation method that can be used to easily investigate the impact on profitability of increasing pregnancy rates and when the culling decision is made. In the microsimulation, the stock was examined without changing any other conditions. A microsimulation method has been developed to determine with high accuracy the effect of the pregnancy rate and the increase in culling days on the economic indicators of individual dairy farms. By microsimulation, the effect of changing these two parameters on the expected milk production of cows, the most important economic indicator for cattle farms, was investigated. The other parameters of economic importance were simulated using a cattle farm database. The purpose of microsimulation is to assist in producing certain managerial decisions in order to achieve better profitability and economic efficiency. In summary, the results showed that increasing the pregnancy rate can successfully reduce the length of the calving interval, but the improved pregnancy rate did not show a significant increase in milk production. In order to obtain results that can be used by farms, the authors intend to further develop the model in the future, adapting it to farms and taking into account their specificities.
... Extended lactation could benefit cow health and production efficiency due to fewer transition periods in the lifespan of the cow. Extending the voluntary waiting period (VWP) for some cows has resulted in higher milk yield per day of calving interval (14,17,18). In addition, extending the VWP can lower milk yield during the last 6 weeks before dry-off and benefit udder health in the following dry period and the next lactation (10,15,18). ...
Article
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When deciding on the voluntary waiting period of an individual cow, it might be useful to have insight into the persistency for the remainder of that lactation at the moment of the insemination decision, especially for farmers who consider persistency in their reproduction management. Currently, breeding values for persistency are calculated for dairy cows but, to our knowledge, prediction models to accurately predict persistency at different moments of insemination are lacking. This study aimed to predict lactation persistency for DIM 305 at different insemination moments (DIM 50, 75, 100, and 125). Available cow and herd level data from 2005 to 2022 were collected for a total of 20,508 cows from 85 herds located in the Netherlands and Belgium. Lactation curve characteristics were estimated for every daily record using the data up to and including that day. Persistency was defined as the number of days it takes for the milk production to decrease by half during the declining stage of lactation, and calculated from the estimated lactation curve characteristic ‘decay’. Four linear regression models for each of the selected insemination moment were built separately to predict decay at DIM 305 (decay-305). Independent variables included the lactation curve characteristics at the selected insemination moment, daily milk yield, age, calving season, parity group and other herd variables. The average decay-305 of primiparous cows was lower than that of multiparous cows (1.55 *10⁻³ vs. 2.41*10⁻³, equivalent to a persistency of 447 vs. 288 days, respectively). Results showed that our models had limitations in accurately predicting persistency, although predictions improved slightly at later insemination moments, with R² values ranging between 0.27 and 0.41. It can thus be concluded that, based only on cow and herd milk production information, accurate prediction of persistency for DIM 305 is not feasible.
... Determining the duration of the VWP is still unclear in dairy cows. Various studies suggest the optimal VWP is between 42 to 150 days for primiparous and multiparous dairy cows (Arbel et al. 2001, Inchaisri et al. 2011, Toledo-Alvarado et al. 2017, Stangaferro etal. 2018. ...
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The objective of the present study was to compare four different synchronization protocols at the end of various voluntary waiting period (VWP) and evaluate the effect of parity and milk yield on pregnancy rates with synchronization in Simmental cows. All animals were randomly allocated into four synchronization groups and one control group. Parity, milk yield (≤23 kg/d; >23 kg/d), and days in milk (DIM; 45-60, 61-90, >90 days) were compared according to synchronization protocols. Ovsynch (Group I; n=81), Ovsynch+Progesterone (Group II; n=30), G6G (Group III; n=66), 2xG6G (Group IV; n=45), and a control group (n=35) were designed for the study. The parity significantly affected the pregnancy rates in the primiparous cows, especially in Group II (P0.05). There was no significant difference between milk yield and pregnancy rates (P>0.05). In conclusion, the synchronization of Simmental cows with Ovsynch, Ovsynch+Progesterone, G6G, or 2xG6G did not affect pregnancy rates across various DIM. These data suggest that the suitable VWP could be planned according to the farm’s economic and local market targets, with veterinarians able to choose a protocol based on practicality, effectiveness and cost, as well as the specific requirements of the herd.
... The high calving interval may be related to poor management practices and other environmental stress that could affect the animal's return to estrus, heat detection, serving, and conception (Genzebu et al., 2016). Hence, the calving interval affects both the total milk production of the dairy herd and the number of calves born and it is considered an important index of reproductive performance (Arbel et al., 2001). ...
Article
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The economy of livestock production largely depends upon the reproductive efficiency of the animals. This review was conducted to review and generate compiled information about the reproductive traits of crossbred cattle such as age at first service (AFS), age at first calving (AFC), calving interval (CI), days open (DO), and number of services per conception (NSPC) under Ethiopian conditions. All published materials are cited to provide some information on the values of reproductive traits of crossbred dairy cattle. It is concluded that improving the management system such as efficient heat detection and timely insemination, better health management, genetic improvement of crossbreeding, and supplementing of good quality feed resources are required for optimal reproduction performance.
... Since the calving interval plays a significant role in determining breeding effectiveness and influences the economics of milk production, early breeding in most modern dairies aims to produce an ideal calving interval of 12 to 13 months. As a result, the calving interval is regarded as a key indicator of reproductive performance 22 . Long mean calving intervals lead to low calf crops and low output levels in dairy cows. ...
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Introduction: The reproductive performance and management of three cattle breeds under extensive management study was investigated due to a lack of baseline data for animal husbandry practices and planning breeding programs in the study area. This study evaluated the productive and reproductive performance, feed resources, feed management, and major constraints of three breeds of cattle (White Fulani, Sokoto Gudali, and Red Bororo) production under an extensive system in Northern Nigeria. Materials and methods: A structured questionnaire survey and group discussion were used for collecting data. 60 farmers with 30 years of experience in cattle farming were selected to administer the questionnaire. Each breed (White Fulani, Sokoto Gudali, and Red Bororo) was grown by 20 farmers. Results: The results indicated that 70% of the farmers agreed with the first service at the age of 2.3-3 years in the three breeds. The first calving at the age of 3.3-4 years was 40% for White Fulani farmers, while 80% for Sokoto Gudali and Red Bororo farmers respectively. The calving interval in the range of 1-2 years was adequately observed in all three breeds. The age of 13-15 years was reported as the female reproductive period in this study. The total number of calves produced per cow's lifetime in the present study was estimated at 8-11 for White Fulani and Sokoto Gudali, and 4-7 for Red Bororo. Feed resources and management of three breeds of cattle under extensive management indicated that natural pasture was the most common source of feed for cattle in the rainy season. Besides, natural pasture, tree leaves, and shrubs were used as cattle feed in the dry season. The main cattle production constraints reported by the farmers included feed and water in the study area. However, the breeds could survive and produce under these major constraints. Conclusion: Alleviating these constraints could improve the productivity of White Fulani, Sokoto Gudali, and Red Bororo in their natural environment.
... This strategy leads to fewer male calves needing to be cared for-but fewer female calves born for replacement must be considered as one of the possible disadvantages. In terms of economic returns from milk, an extended calving interval (+ 60 days) might even be advantageous, especially in primiparous cows (Arbel et al. 2001). To maintain the license to produce, the dairy sector needs to find practical and socially accepted alternatives that reduce ethical concerns regarding the handling of male dairy calves and reduce the gap between consumer expectations and the reality on farms. ...
Article
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Consumers’ actual knowledge about modern food production is limited, and their judgment is often guided by assumptions or associations that are not necessarily in line with reality. Consumers’ rather unrealistic idea of livestock farming is driven by beautiful and romanticized pictures in advertising. If confronted with the reality of modern livestock farming, consumers’ responses are mainly negative. So far, dairy farming still has a more positive image and thus is less affected by public criticism. However, if made public, some of the current production practices in dairy farming have the potential to reduce consumer acceptance which in turn can have a tremendous effect on farmers. A particularly urgent topic is the handling of male dairy calves. Such calves are often treated as surplus animals due to their low genetic merits for meat, with the risk of resulting in the deprivation of animal welfare. To maintain consumer acceptance of dairy products and find socially accepted alternatives for the handling of male calves, insights into consumer perception of current and future production practices in dairy farming are needed. Thus, the aim of this study is to analyze how consumers evaluate the current situation of male dairy calves and alternatives in male calf management. A quantitative online survey, representative for the German population in terms of gender, age, education, region, and income, was carried out with 1 194 participants in February 2022. Overall, 60% of participants were not aware of the fact that male dairy calves are less appropriate for fattening purposes. Respondents saw a clear need for alternative methods for handling male calves from dairy production. More, our results show that the use of sexed semen encounters consumer resistance, while other alternatives that were evaluated as more natural were more accepted. A cluster analysis identified 3 distinct consumer segments labelled “sexed semen opponents” (31.6%), “undecided” (30.4%), and “proponents of all alternatives” (38.0%) that differed in their acceptance of alternative handling practices of male dairy calves. The results emphasize the gap between consumers’ expectations and reality on farms and the importance of considering consumer preferences when developing future pathways for dairy farming.
... Therefore, 34 DIM was the cut-off value that better establish a relationship between the DIM in which cows reached the nadir of BCS and the P150. The P150 was chosen as a reference due to cows that became pregnant by 150 DIM presented economic advantages and adequate reproductive performance (calving intervals of ~14 months; adapted from Arbel et al., 2001). ...
Article
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This study aimed to compare milk production and reproductive performance in high yield Holstein cows that lose BCS early and late in the postpartum period. Lactating dairy cows (n = 76) were received first timed AI at 60 to 75 DIM using the farm-managed estradiol-progesterone-GnRH–based timed AI protocol. The BCS of all cows was daily evaluated by automated BCS cameras. Aiming to evaluate the effect of the days in milk (DIM) in which a cow reached the nadir BCS on the reproductive parameters, cows were separated into two groups: early BCS loss (n = 42), cows that reached the nadir BCS ≤ 34 DIM, and late BCS loss (n = 34), cows that reached the nadir BCS > 34 DIM. The optimal cut-off point for determining the relationship between days to nadir BCS and pregnancy by 150 DIM (P150) was calculated using the receiver operating characteristic (ROC) curve. From the ROC analysis, the cut-off was 34 DIM (Se, 80.9%; Sp, 66.7%; AUC, 0.74; P < 0.01). No differences (P>0.05) were detected between groups on the BCS and milk production. The average of milk production in both groups was 46.65 ± 6.15 Kg/day. Cows that reached the nadir BCS early postpartum presented lower (P < 0.01) calving interval and greater (P < 0.01) pregnancy at first AI and P150. In summary, cows that lost BCS early had better reproductive performance and had similar milk yield compared with cows that lost BCS late in the postpartum period.
... Therefore, the cut-off value that better establish a relationship between the DIM in which the nadir of BCS was observed and the P150 was 34 DIM. The P150 was chosen as a reference due to cows that became pregnant by 150 DIM presented economic advantages and adequate reproductive performance (calving intervals of ~14 months; adapted fromArbel et al., 2001). ...
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This study aimed to compare milk production and reproductive performance in high yield Holstein cows that lose BCS early and late in the postpartum period. Lactating dairy cows (n = 76) were received first timed AI at 60 to 75 DIM using the farm-managed estradiol-progesterone-GnRH based timed AI protocol. The BCS of all cows was daily evaluated by automated BCS cameras. Aiming to evaluate the effect of the days in milk (DIM) in which a cow reached the nadir BCS on the reproductive parameters, cows were separated into two groups: Early BCS loss (n = 42), cows that reached the nadir BCS ≤ 34 DIM, and Late BCS loss (n = 34), cows that reached the nadir BCS > 34 DIM. The optimal cut-off point for determining the relationship between days to nadir BCS and pregnancy by 150 DIM (P150) was calculated using the receiver operating characteristic (ROC) curve. From the ROC analysis the cut-off was 34 DIM (Se, 80.9%; Sp, 66.7%; AUC, 0.74; P < 0.01). No differences (P>0.05) were detected between groups on the BCS and milk production. The average of milk production in both groups was 46.65 ± 6.15 Kg/day. Cows that reached the nadir BCS Early postpartum presented lower (P < 0.01) calving interval, and greater (P < 0.01) pregnancy at first AI and P150. In summary, cows that lost BCS early had better reproductive performance and had similar milk yield compared with cows that lost BCS late in the postpartum period.
... Parity number has been studied extensively in relation to dairy cattle milk yield during both gestation and parturition. Studies have demonstrated that the conventional milking method maximizes milk yield within the fourth or fifth parity when parity numbers increase [15]. In our study, milk yield increased with increasing parity number, presumably due to growing udder size and development, as well as an increase in secretory cells [16]. ...
Article
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This survey investigated, using robotic milking and rumen sensors, the effects of an adjusted temperature–humidity index (THI) in different geographical areas on milk yield, fat and protein, rumen temperature, and activity in lactating Holstein cows. We additionally explored the effect of parity on milk and rumen temperature and activity under different THI levels during the summer. From January to September 2020, four farms (276 dairy cows) were subjected to the use of robot milking machines, and two farms (162 dairy cows) to the use of rumen sensors. For the temperature and humidity data, the THI was calculated on the basis of the data from the Korea Meteorological Administration (KMA). The data were analyzed using the GLM procedure of SAS. Milk yield and milk protein decreased (p < 0.05), and milk fat increased (p < 0.05) at all farms during the summer, from July to August, when the temperature and humidity were high (THI = 72–79). Milk yields were the highest in the fifth, sixth, seventh, and eighth parities, and the lowest in the fourth (p < 0.05). Milk fat concentration was the highest in the fourth parity and the lowest in the first parity (p < 0.05). In the first parity, the highest levels of milk protein and lactose were seen (5.24% and 4.90%, respectively). However, milk protein concentration was the lowest in the third parity, and the lactose concentration was the lowest in the fifth, sixth, seventh, and eighth parities. According to the rumen sensor, the rumen temperature of the dairy cows at the two farms also continued to increase (p < 0.05) from July to August, and then decreased (p < 0.05) in September. However, the activity in the rumen was increased (p < 0.05) from July to September. In the second parity, the highest rumen temperature (39.02 °C) was observed, while the lowest value (38.28 °C) was observed in the third parity. The highest value of rumen activity (12.26 mg) was observed in the second parity and the lowest value (11.31 mg) in the fourth parity. These data, taken together, confirm that a high THI during summer conditions negatively affects milk yield, milk protein content, and rumen temperature and activity in lactating Holstein cows. It is also demonstrated that various parities affect milk characteristics and the rumen environment in the summer season.
... In cows and heifers, fertility is the ability to enter the estrous cycle and successfully maintain pregnancy until calving and maintain calving pattern. Calving intervals tend to fall within a 12-to 13-month timeframe (Arbel et al., 2001). For beef cattle, females begin to re-cycle and be rebred within 45-60 d of calving to maintain this calving interval. ...
Article
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The human population is ever increasing while the quality and quantity of natural resources used for livestock production decline. This calls for improved product efficiency and the development of improved and sustainable cattle production methods to produce higher quality products to satisfy the demands of both the modern and transient world. The goal of this review was to summarize the interactions, challenges, and opportunities in cattle production relating to their endocrine system, and how reproductive hormones and others impact economically important traits, animal welfare, and human health. A comprehensive literature search was conducted with a focus on analysis of natural hormones and the use of exogenous hormone administration for reproduction, growth, and development of beef and dairy cattle. Hormones regulate homeostasis and enhance important traits in cattle, including fertility, growth and development, health, and the production of both meat and milk products. Reproductive hormones such as testosterone, estradiol, progesterone, and related synthetics like trenbolone acetate and zeranol can be strategically utilized in both beef and dairy cattle production systems to enhance their most valuable traits, but the impact of these substances must account for the welfare of the animal as well as the health of the consumer. This scientific review provides a comprehensive analysis of the bovine endocrine system's impact on food animals and product quality which is vital for students, researchers, livestock producers, and consumers. Although important advances have been made in animal science and related technological fields, major gaps still exist in the knowledge base regarding the influence of hormones on the production and welfare of food animals as well as in the public perception of hormone use in food-producing animals. Filling these gaps through transformative and translational research will enhance both fundamental and applied animal science to feed a growing population.
... Profitability in dairy farming is also influenced by the birth rate of live calves [40]. Despite the development of rearing systems, perinatal mortality (stillbirths) is still very high in confined systems ranging from 5 to 9.6% [41]. ...
Article
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Purpose: The objective of this review is to describe the main technologies (automated activity monitors) available commercially and under research for the detection of estrus and calving alerts in dairy cattle. Sources: The data for the elaboration of the literature review were obtained from searches on the Google Scholar platform. This search was performed using the following keywords: reproduction, dairy cows, estrus detection and parturition, electronic devices. After the search, the articles found with a title related to the objective of the review were read in full. Finally, the specific articles chosen to be reported in the review were selected according to the method of identification of estrus and parturition, seeking to represent the different devices and technologies already studied for both estrus and parturition identification. Synthesis: Precision livestock farming seeks to obtain a variety of information through hardware and software that can be used to improve herd management and optimize animal yield. Visual observation for estrus detection and calving is an activity that requires labor and time, which is an increasingly difficult resource due to several others farm management activities. In this way, automated estrous and calving monitoring devices can increase animal productivity with less labor, when applied correctly. The main devices available currently are based on accelerometers, pedometers and inclinometers that are attached to animals in a wearable way. Some research efforts have been made in image analysis to obtain this information with non-wearable devices. Conclusion and applications: Efficient wearable devices to monitor cows’ behavior and detect estrous and calving are available on the market. There is demand for low cost with easy scalable technology, as the use of computer vision systems with image recording. With technology is possible to have a better reproductive management, and thus increase efficiency.
... cows (Arbel et al., 2001). In practice, farmers that want to extend the CInt on their farm select specific cows for an extended VWP. ...
Article
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Based on modeling studies, a 1-yr calving interval for dairy cows is generally considered optimal from an economic point of view. Recently some dairy farmers are deliberately extending the voluntary waiting period for insemination (VWP) to extend the calving interval. Reasons to extend the VWP are to reduce the frequency of transitions such as dry-off and calving to improve health, to reduce labor associated with these transitions, and to reduce the number of surplus calves. This study aimed to evaluate yearly revenues, yearly costs, and yearly net partial cash flow (NPCF) for individual cows with a VWP of 50, 125, or 200 d based on data from a randomized control trial. The NPCF included revenues and costs for milk yield, calves born, inseminations, concentrate supply, partial mixed ration (PMR) supply, veterinary treatments, discarded milk due to veterinary treatments, culling, and labor (for milking, calving cows, inseminations, and veterinary treatments). Holstein-Friesian dairy cows (n = 153) within one herd were blocked for parity, calving season, and expected (primiparous cows) or previous (multiparous cows) 305-d milk yield. Cows were randomly assigned within the blocks to 1 of 3 VWP (VWP50, VWP125, or VWP200) in wk 6 after calving, and monitored from wk 6 after calving until wk 6 after the next calving or until culling. Revenues and costs were calculated per individual cow and expressed per cow per year. Revenues from milk and costs for PMR and concentrate contributed most to the yearly NPCF. Total yearly revenues were greater in VWP50 compared with VWP200 (€3,169 vs. €2,832), mainly because of €334 greater milk revenues. Total yearly costs were also greater in VWP50 compared with VWP200 (€1,964 vs. €1,729), mainly because of €102 greater concentrate costs. The VWP was not significantly associated with the NPCF per cow per year. A change in milk, feed, or calf price, or a change in labor costs for calving cows or for inseminations had a greater effect on the yearly NPCF of cows in VWP50 compared with cows in VWP200. To investigate variation in NPCF, cows were grouped for yearly NPCF and categorized into 3 economic classes (EC): EC1 (<€1,100/yr), EC2 (€1,100-€1,400/yr), and EC3 (>€1,400/yr). Cows in EC3 had greatest lactation production per day in the experiment (i.e., kg of milk, protein, fat, lactose), and lowest number of veterinary treatments during the experiment.
... If pregnancy is not detected at an early stage, it results in an extension of the calving interval and consequently reduced milk production. It causes economic losses [5,6]. Improving reproductive performance by increasing the pregnancy rate and shortening the calving intervals is a consequence of early pregnancy detection in cows after insemination [7]. ...
Article
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Several decades of improving dairy cattle towards unilateral utilization of dairy cattle led to enormous progress in the field of milk yield; however, it resulted in a number of unfavorable features, such as reproductive disorders, increased calf mortality, and reduced health. Most cases of embryo loss and/or lost pregnancies occur during the first four to five weeks of gestation; accurate detection for pregnancy during this period is likely to contribute to an improvement in gestation rates. A specific protein, interferon-tau (IFNT), stimulates interferon-stimulated genes (ISGs), and their expression increases during gestation within 21 days after insemination. In bovines, the early conceptus undergoes a phase of rapid growth and elongation before implantation, the latter occurring 2-3 weeks after fertilization. IFNT acts mainly in the endometrium of the luminal epithelium. It is a new type I interferon that regulates several genes encoding uterine-derived factors. They are crucial in the processes of preparing the uterus for placenta attachment, modifying the uterine immune system, and regulating early fetal development. Because IFNT is expressed and induces ISGs in the endometrium during pregnancy recognition, it was reasoned that surrogate markers for pregnancy or IFNT might be present in the blood and provide an indicator of pregnancy status in cattle.
... On the other hand, younger cows took longer to attain peak milk yield than older cows and this response seems to be because young cows are not physically mature (Coffey et al., 2006); when they are approaching their first lactation they are in a different metabolic state compared with that of multiparous cows because they require nutrients for their continued growth in addition to that of their udder development and milk synthesis (Wathes et al., 2007). Many studies on the effect of lactation number on milk yields of cows have been conducted and essentially all studies have demonstrated that milk production increases with lactation number and is maximized in the fourth or fifth lactation (Arbel et al., 2001). This is a result of the increasing development and size of the udder (Sorensen et al., 2006) with a consequent increase in the number of secretory cells (Dado and Allen, 1994). ...
Article
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This study has assessed the effects of parity on lactation length, lactation milk yield, and lactation curves for each lactation stage at Haramaya University dairy research and teaching farm. Thirty-one synchronized Holstein Frisian crossbred heifers; with nearly similar age were selected and stall-fed for the whole lactation period. Data were collected on daily milk yield at each stage, days in milk and lactation milk yield, 305 days milk yield, and analyzed using the t-test for means. There was an insignificant effect on lactation length, total lactation milk yield, 305 days total milk yield, mid and late lactation milk yield between the 1st and 2nd lactation numbers. The rate of variation was very high (13.4%) during the early lactation stage. The daily milk yield was significantly influenced by parity (P<0.05). The variation rate of milk yield in the morning milking was ranging from 10- 51%.Further study is required to examine additional aspects of parity on lactation traits such as milk composition and reproductive traits with more lactation numbers
... On the other hand, younger cows took longer to attain peak milk yield than older cows and this response seems to be because young cows are not physically mature (Coffey et al., 2006); when they are approaching their first lactation they are in a different metabolic state compared with that of multiparous cows because they require nutrients for their continued growth in addition to that of their udder development and milk synthesis (Wathes et al., 2007). Many studies on the effect of lactation number on milk yields of cows have been conducted and essentially all studies have demonstrated that milk production increases with lactation number and is maximized in the fourth or fifth lactation (Arbel et al., 2001). This is a result of the increasing development and size of the udder (Sorensen et al., 2006) with a consequent increase in the number of secretory cells (Dado and Allen, 1994). ...
... Although each of these reproductive measures affects the dairy business's profitability in a slightly different way but the calving interval affects both the total milk production of the dairy herd and the number of calves born. Again, milk production levels and lactation persistency are crucial factors for determining the appropriate calving intervals (Arbel et al., 2001). The conventional dairy animals feeding methods are based on the rice straw, natural grass supplemented with few or no concentrate mixture. ...
... Quarter milk flow parameters could be useful information for automated monitoring of health problems (Schukken et al., 2003;Tancin et al., 2003). Many studies established that milk yield increases with increasing the lactation number (Vijayakumar, 2017;Arbel et al., 2001), whereby the analysed milking traits came from separate udder quarters (Tancin et al., 2006). However, there were no studies focused on determining the relationship among cows' lactation and milking traits from each quarter. ...
Article
The study was conducted on 229 dairy cows in Lithuania. DeLaval milking robots were used for cows’ milking. Milk yield (kg), milking duration (min), milk flow (kg/min), peak flow rates (kg/min) by cow lactation in separate udder quarters were analyzed. The statistical analysis of the research data was performed using the data collection and analysis program package Statistical Package for Social Science 22 for Windows, Kolmogorov-Smirnov test and One-Factor Dispersion Analysis (ANOVA) model. Distribution of the udder quarters is very important in the cow milking process. Milk yield from cow front udder quarters was about 4.6 kg (42.2 %) and from rear udder quarters 6.32 kg (57.8 %) (P<0.05). The milk content in front quarters was significantly lower than in the rear udder quarters in all dairy cows (P<0.05). Cows of the first lactation showed lower milk production per milking in all udder quarters when compared to other lactation cows (P<0.05). The duration of milking of cows in third and more lactation in front quarters was shorter than that of the first lactation cows (P<0.005). Along the increase in the number of cows’ lactations, the milking time in the front quarters decreased. The average milk flow and the peak flow in the first lactation cows were found to be lower than that in older cows (P<0.05).
... Низька запліднюваність від штучного осіменіння визначає тривалий сервіс-період, який, у свою чергу, впливає на показники міжотельного періоду (МОП). Через низькі показники виникають тривалі інтервали між отеленнями та збільшуються витрати на відтворення (Arbel et al., 2001). ...
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The article presents the productive and reproductive qualities analysis that characterize the adaptive ability to the conditions of a large industrial complex for the milk production and intensive technology of Holstein and Brown Swiss cows’ usage. To achieve this aim was made an analysis of the productive qualities’ implementation of Holstein and Brown Swiss cows on industrial complexes of milk production. Using the balanced group method, two groups of cows were formed in each by following structure: first-calf heifers – 44%, cows of the second and third lactations – 28% each. The first group was formed from Holstein cows (I, n = 125), and the second group was formed Brown Swiss cows (II, n = 125). It was found that under the industrial milk production, the cows’ lactation period in both Holstein and Brown Swiss breeds is elongated – by 1.23 and 1.16 times higher than normal, respectively. While lactation in Brown Swiss cows averages 355.1 days, it is still 5.29% shorter than in Holstein cattle (P < 0.001), in which it is approximately 373.9 days. It was proved that Holstein cows during their lactation period produced averaged 8839.1 kg of 4% milk, which was inferior to the physical mass by 3.69%. An average of 10 344.5 kg of 4% milk was obtained from Brown Swiss cows for complete lactation, which is 0.4% higher than the physical mass. Namely, if in the Holstein cows the total weight of 4% milk was less than the physical mass, then in Brown Swiss cows, on the contrary, it was higher. At the same time, the level of dairy productivity of Brown Swiss cattle is higher than that of Holstein cows by 14.55% (P < 0.001). It was revealed that the milk quality indicators depending on the animals’ breed. The mass fraction of fat in milk of Holstein cows was on average 3.80%, and in Brown Swiss – on average 4.0 3%, which is 0.23% more in absolute terms (P < 0.001). Animals of two breeds differ significantly in terms of protein content. In Holstein, the mass fraction of protein in milk averaged by 3.25%, while in Brown Swiss this indicator was higher in absolute terms by 0.48% (P < 0.001) and averaged by 3.75%. It is proved, that animals of two breeds had satisfactory reproductive function indicators. In cows of Brown Swiss breed the insemination index averaged by 3.54 units. In Holstein cows, this indicator was at the level of 5.9 units, which is higher than in Brown Swiss by 40.0% (P < 0.001). In Brown Swiss cows, calving-to-conception interval was 140.7 days. At the same time, this indicator in Holstein cows averaged by 202.9 days, which exceeded the Brown Swiss value by 30.66%(P < 0.001). It was found that in the Brown Swiss cows, the infertility period, although long, did not exceed an average of 98.7 days, whereas in Holstein it was at the level of 131.9 days, which is 25.17% more (P < 0.001). In Brown Swiss cattle, 0.35 of calves was not received per animal, and in Holstein cows, this indicator was 23.91% higher (P < 0.001) and averaged by 0.46 calves. It was determined, that the adaptation index for Holstein cows was at the level of 2.55 units. At the same time, in Brown Swiss cows this indicator was higher by 29.2% and averaged by 3.60 units. Thus, in animals of two breeds, there was only a slight imbalance between their body and the environment of exploitation.
... Breeding management was carried out by AI with Holstein semen and performed by a highly trained technician or veterinarians specialized in cattle reproduction (Lleidavet S.L.P, Alpicat, Lleida, Spain). Reproductive performance in cows was assessed through the average number of AI per pregnancy and calving interval [23,24]. Calving interval is defined as the average number of days elapsed between current and previous calving. ...
Article
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Female calves, checked for serum total protein ≥ 5.8 g/dL before 5 days of life, entered the study at 22 days of age after having received pasteurized colostrum and milk (P group, n = 127), or non-pasteurized colostrum and milk (NP group, n = 134). During the heifer-rearing period, productive (body weight; BW) and health parameters (bovine respiratory disease (BRD) and diarrhea) were recorded. Productive (305-d milk yield), reproductive (AI per pregnancy and calving interval), and health parameters (milk somatic cell count; SCC/mL), as well as age at culling, were recorded in a follow-up study. Feeding on-farm pasteurized colostrum and milk during the first 21 days of life reduced morbidity of bovine respiratory disease during the first year of life and diarrhea during the first 180 days of life. Moreover, it increased BW at calving during the first three lactations. It also significantly increases milk production during the first lactation. However, there were no differences in relation to reproductive performance and health of cows in the NP or P group. These results highlight that feeding calves with pasteurized colostrum and milk could improve health and production parameters throughout the heifer-rearing process and during their first lactation.
... Our study revealed significant differences in milking characteristics such as peak milk yield, peak time, and persistency (p < 0.01). The results are consistent with the findings of previous studies [44][45][46][47][48][49], which reported that total milk yield in a 305-d lactation increases with an increase in the parity of Holstein cows. Particularly, some studies reported that peak milk yield increased dramatically from parity 1 to parity 2, and peak milk yield was observed at later periods in primiparous cows and earlier in multiparous cows [47,48]. ...
Article
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The aim of the study was to group the lactation curve (LC) of Holstein cows in several clusters based on their milking characteristics and to investigate physiological differences among the clusters. Milking data of 330 lactations which have a milk yield per day during entire lactation period were used. The data were obtained by refinement from 1332 lactations from 724 cows collected from commercial farms. Based on the similarity measures, clustering was performed using the k-medoids algorithm; the number of clusters was determined to be six, following the elbow method. Significant differences on parity, peak milk yield, DIM at peak milk yield, and average and total milk yield (p < 0.01) were observed among the clusters. Four clusters, which include 82% of data, show typical LC patterns. The other two clusters represent atypical patterns. Comparing to the LCs generated from the previous models, Wood, Wilmink and Dijsktra, it is observed that the prediction errors in the atypical patterns of the two clusters are much larger than those of the other four cases of typical patterns. The presented model can be used as a tool to refine characterization on the typical LC patterns, excluding atypical patterns as exceptional cases.
Article
Dairy farms must constantly evolve to achieve sustainability goals, including profitability, minimal environmental impacts, and improving the well-being of cows and people. Data-driven management practices and automated technologies are a growing opportunity for improving the sustainability of reproductive management. Precision livestock farming technologies coupled with other herd management data, genomic information, and environmental monitoring tools are enabling the development of data-driven targeted reproductive management and automation of management tasks. An improved understanding of associations between putative data predictors of reproductive outcomes enables targeted reproductive management for cows that share similar expected performance or biological features. Tailored management interventions can be applied on subgroups of cows based on automated estrus alerts, genomic predictions, and ovarian status at the time of non-pregnancy diagnosis. Targeted interventions can lead to shorter interbreeding intervals, increased fertility, and fewer unnecessary interventions on cows. Major advances in engineering, advanced data analytics, and a better understanding of dairy cattle biology through data have also enabled progress with automation of management tasks such as detection of estrus, synchronization of ovulation, and pregnancy testing. Although concerted efforts in research and application are still needed to fully realize the full sustainability benefits of data-driven management and automation, collectively these innovations are reshaping reproductive management of dairy cattle.
Article
Extending lactation length reduces the frequency of critical calving events for the cow and herewith reduces the frequency of periods with increased risk for health problems. Moreover, breeding is postponed until a moment later in lactation, which is associated with better conception rates and less days open after start of the breeding period in most studies. Potential risks of an extended lactation are that milk yield of cows at the end of the lactation may be too low which may lead to cows being overconditioned at the end of the extended lactation. Therefore, extending lactation length might not fit every cow. Individual cow characteristics like parity, milk yield level, or body condition determine the response of the cow to an extended lactation. These individual cow characteristics can be used in customized management strategies to optimize lactation length for individual cows. Customized lactation length for individual cows could limit the impact at herd level of disadvantages concerning milk losses and overconditioning and maintain benefits for improved cow health and fertility, reduced number of surplus calves and increased work satisfaction for the farmer. In conclusion, extending lactation length has interesting perspectives for health and fertility of high‐producing dairy cows, although questions remain concerning management approaches to support lactation persistency of cows with an extended lactation, and consequences for calf health and development. Moreover, ongoing studies aim to develop decision support tools to select individual cows for a specific lactation length.
Article
The objective of this study was to compare the effect of early or late breeding on milk production in high producing dairy cows. In this aim, the cows with previous average peak milk yield above 45 kg/d (n = 48) were divided into two groups; Group1 (early bred) included the cows (n = 21) were inseminated between 45 to 75 days in milk (DIM) and Group2 (n = 27; late bred) were inseminated between 76 to 124 DIM. The cows that became pregnant at their first insemination following first estrus selected for the study. Milk yield was recorded every 5 days after calving for the first 45 days then continued for every 15 days for every each cow. Average DIM in early and late bred cows at insemination were 66 (min, 45; max, 75) and 99 (min, 76; max, 124), respectively. Average milk yield up to 271 d was similar between groups, however, average milk yield from 227 to 271 d was lower (P < 0.04) in early bred cows with 26.7 kg/d compare to late bred cows with 30.3 kg/d. Even, there was no relationship between average milk yield up to 271 d, peak milk yield and day of insemination, it may be concluded that milk yield continues with more pronounced stability through the end of lactation in late bred high yielding cows.
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Purpose. The purpose of the article is to substantiate the methodological approach to forecasting the selling price of milk, which is produced and sold by agricultural producers in the Ukrainian market of raw milk. Methodology / approach. The basis of the methodological approach is the construction of models describing the change in sales prices for milk and certain types of dairy products (pasteurized milk with a fat content of up to 2.5 %, sour cream with a fat content of up to 15.0 %, soft fat cheeses) during 2017–2019 and forecasting the sale price of milk for a period of 6 months. The ARIMA model was used in the forecast, taking into account the degree of correlation between changes in the price of milk and the analyzed types of dairy products. The time factor (time lag) of one month and the share of milk in the price of the finished dairy products were also considered. Results. The forecast results allowed us to determine milk sales prices for January–June 2020. In addition, the study showed the lack of a single direction in their change during the bias period, namely – increase in milk sales price during February–January 2020 and its reduction till June 2020. The obtained forecast values of milk selling price, considering the share of milk in the selling price of finished dairy products, were adjusted according to the time lag. Originality / scientific novelty. Novelty is an algorithm for using a methodical approach to forecasting the purchase price of milk, taking into account the correlation between milk prices and prices for certain types of dairy products; time lag and the share of milk prices in the sale price of finished dairy products. Practical value / implications. Comparison of the obtained forecast data of the price with the actual prices of milk sales indicated the existence of insignificant differences between them, proving the adequacy of the proposed methodological approach to be used in forecasting of milk prices at the enterprises.
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Background and Aim: Milk yield (MY) is one of the main factors that affect the economic profitability of dairy farms. Thus, increasing the MY per animal and decreasing the feed cost can lead to economic gains, so the objective of this study was to evaluate the effect of dry period length (DPL), days open (DO), and days in milk (DIM) on the productivity and profitability of dairy cow farms. Materials and Methods: Data used in this study were taken from 3095 lactation records of Friesian dairy cows of private and governmental sectors. The data were classified into 4 DPL categories: DPL1 75 days, 3 DO categories: DO1 ≤90 days; DO2 91-110 days and DO3 >111 days, and 8 DIM categories: DIM1 180-210 days; DIM2 211-240 days; DIM3 241-270 days; DIM4 271-300 days; DIM5 301-330 days; DIM6 331-360 days; DIM7 361-447 days; and DIM8 >447 days. Results: The average net profit (NP) was significantly different (p
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This review considers the likely impact of changing consumer requirements, political pressure, economics and technological advances on the dairy production industry of the future. The vision is one of diverse strategies of production, the majority of milk being produced from cows managed technologically with much greater regard for welfare, with a number of ‘romantic’ strategies such as organic, extensive or dual-purpose production supplying niche markets. The important novel feature of the technological strategy will be an escape from the intensive twelve-month lactation cycle to extended lactations of, say, eighteen months, since this will reduce the number of times the cow is exposed to metabolic and other stresses associated with parturition, peak lactation and rebreeding.
Article
Relative economic merits of three heat detection rates and three conception rates were evaluated by mathematical modeling and dynamic simulation. Three heat detection programs evaluated were: a) poor, with no specific time set aside for detection and detection rate of .35; b) average, with two 45-min observations each day and detection rate of .55; c) good, with three 45-min observations each day and detection rate of .75. Changing heat detection program from poor to average and average to good de- creased days open from 136 to 119 and to 105. Corresponding increases in net return per cow per year were 60and60 and 4. Three breeding programs evaluated were: a) poor, direct service by an in- experienced inseminator and conception rate of .42; b) average, professional artificial inseminator servicing the cows with a single insemination at each service and conception rate of .50; c)good, professional artificial inseminator using two inseminations during each service period and conception rate of .58. Changing breeding program from poor to average and average to good decreased days open from 123 to 119 and to 115. Corresponding changes in net return per cow per year were an increase of 39andadecreaseof39 and a decrease of 7.
Article
The effect of days open and days to first breeding on cumulative calf and milk production in the current and following lactation was studied based on annualized yield in 121.627 Israeli-Holstein lactations. Optimum days open for first parity ranged from 110 for low calf value (500 kg milk) to 91 for high calf value (4000 kg milk). Optimum days open for second parity ranged from 91 for low calf value to 40 for high calf value. Expected production as a function of days to first breeding was computed as a function of probability of conception, which was varied from .4 to .6, and estrus detection, which was varied from .5 to .7. Optimum days to first breeding as a function of calf value and reproductive management ranged from 95 to 65 d for first parity and from 77 to less than 40 d for second parity. Optimum days to first breeding was higher with lower calf value and better reproductive management. Expected losses from early first breeding (40 d in milk), as compared with the optimum, ranged up to 780 kg of FCM for first parity cows, while expected losses from late first breeding (120 d in milk) ranged up to 790 kg for second parity cows.
Article
The study sought to answer the questions: when is the optimal time of conception for a given type of cow? and what is the economic cost of deviations from this optimum? The general approach was to model the incomes and costs over two consecutive lactations for a cow with certain given characteristics, namely calving month, parity and production level. The effect on net return per year (NRPY) of changing the time of conception, from 60 to 220 days postpartum, for such a cow was then studied. For all combinations of characteristics early conception was the most profitable. The effect on NRPY of a delayed pregnancy by one day varied from 0.3 Sw. kr to 11.6 Sw. kr depending on calving month, stage of lactation, parity and production level. A change in the two former substantially affected the loss in NRPY per day of delayed pregnancy. An increase in the two latter gave a small but consistent increase in the loss per day of delayed pregnancy. The seasonal variation in milk price had a large impact on the relationship between NRPY and time of conception.
Article
Effects of early and late breeding post partum on reproduction and produc- tion were investigated in a Holstein herd. Cows were assigned randomly to two groups at calving: an early group bred at the first observed heat following 50 days postpartum and a late group bred at first observed heat 80 days post- partum. Early versus late breeding re- sulted in intervals to first service of 72 + 18 or 93 +- 17 days; conception at 88 + 33 or 121 + 40 days postpartum; and 1.50 (range 1 to 3) or 1.96 (range 1 to 5) services per conception. Postpartum reproductive activity was monitored with milk progesterone analy- ses. Average duration of first estrous cycle was 17 + 7.5 days. The first heat detected by milk progesterone occurred 33 -+ 10 days postpartum compared to the first observed heat at 48 + 26 days postpartum. Calving problems and calving in pasture season delayed conception in the late bred group but did not influence conception in the early bred group. The late bred group produced more fat- corrected milk in 305-day lactation and in the first 150 days of the subsequent lactation. Average daily milk production from beginning of current lactation to day 150 of subsequent lactation (includ- ing the dry period) was the same for both early and late bred groups.
Article
A budgeting procedure using a micro- computer spreadsheet program was used to determine the effect of calving inter- vals on income over feed and variable costs using various milk yields of cows, milk and feed prices, and culling strate- gies based on either age of cow or lacta- tion number. When the culling strategy was based on age of cow with a 12milkpriceandlowfeedprices,incomeoverfeedandvariablecostsofcowsduringa13mocalvingintervalwasslightlylowerthanthoseduringa12mocalvinginterval.Lossesforeachadditionaldayofcalvingintervalfrom12to13mo,andthusdayopen,rangedfrom0to12 milk price and low feed prices, income over feed and variable costs of cows during a 13-mo calving interval was slightly lower than those during a 12-mo calving inter- val. Losses for each additional day of calving interval from 12 to 13 mo, and thus day open, ranged from 0 to .13. Increasing the calving interval to 14 mo increased the losses per day open with a range of .10to.10 to .71 in comparison with a 12-mo interval. Losses per day open for a 15-mo calving interval ranged from .18to.18 to .60 in comparison with a 12-too interval. Factors that reduce income over feed costs, such as lower production, lower milk prices, higher feed prices, and culling at an earlier age decrease the loss in income over feed and variable costs for 14- and 15-too calving intervals in com- parison with a 12-mo interval. When the culling strategy was based on lactation number, extending the calving interval increased the income over feed and varia- ble costs with the greater effect occurring between 12 and 13 too. From these re-
Article
Multiparous cows were assigned before calving to three calving to first insemination intervals. Records of cows conceiving at first or second insemination, were used to construct a model of the lactation curve which incorporated peak production and the effect of progressing pregnancy. The model was used to simulate milk yield during a 4-year period for three production levels and five calving intervals. The model separated the descending part of the lactation curve into a linearly and an exponentially declining component, with the latter becoming distinct at about 20 weeks after conception. Peak yield was negatively correlated with the slope of the linear decline. Within a simulated 4-year period, cumulative milk yields at fixed time periods after calving depended upon the period chosen and the calving-to-conception interval of the cow. Late conceptions resulted in higher cumulative yields at the end of the 1st year, and in lower yields at the 2nd year end, with respect to early conceptions. Smaller differences were found between the intermediate calving intervals. During the 3rd and 4th years the early conceptions had a distinct advantage. Different rates of the linear decline, obtained for the different production levels, changed the magnitude of the yield differences between the calving intervals but not their relative ranking. The model presented offers a means for the suitable choice of the calving cycle according to the length of the period for which a cow is expected to remain in the herd.
Article
The effects of days-open on milk yields in current lactations and in following lactations were estimated from 71 911 current and 68 693 following lactation records. Yields were expressed as 305-day, total and annual records, where annual record = 365 × (total yield/days between calvings). The data were grouped according to current days-open, corrected for initial yield differences and analysed separately for heifers and cows in Moshav (moderate-yielding) and Kibbutz (high-yielding) herds. Current 305-day records increased by 15 to 18 kg milk/day-open up to 90 days-open, and 2 to 3 kg/day-open thereafter. In contrast, the effects of increasing days-open on annual yields were generally small and negative, being positive only for heifers up to 90 days-open. Thus 305-day records heavily under-rated annual yields of fertile cows. For current lactations, 70 to 100 days-open for heifers and 30 to 50 days-open for cows resulted in the highest annual production. Yields in following lactations were positively associated with days-open in the previous lactation. The effect was highest in high-yielding herds, suggesting that high-yielding cows respond positively to some rest between calvings. Combining the effects of days-open on current and following lactation yields and on the calf crop: in high-yielding herds heifers had the highest productivity when mated not earlier than 70 days post partum , while in moderately-yielding herds days-open did not affect productivity. Cows in high-yielding herds achieved highest productivity at 41 to 90 days-open, while cows in moderately-yielding herds were most productive when mated as early as possible. A comparison of the economic value of sire fertility and sire transmitting ability for milk production showed that fertility may often be over-rated.
Article
Few investigations have been performed where effects of a planned increase of the calving interval have been elucidated. In order to study these matters, a research project has started at the Swedish University of Agricultural Sciences (SLU). The study involves researchers both at the Agricultural and Veterinary Faculties at SLU as well as from the dairy industry in Sweden. Experiments are being performed within two experimental herds (approximately 150 cows) belonging to SLU. We are now in the middle of a three-year study comparing 12- and 15-month calving intervals (herd 1) or 12- and 18-month calving intervals (herd 2). In herd 2, two milking frequencies (2 vs. 3 per day) are combined with the two calving intervals. Long-term effects on health, reproduction, milk production (including milk quality) and production efficiency are studied in detail. The plan is to study individual cows in three consecutive years. Interactions with management system and breed will also be investigated. Results from the first lactation show no significant differences in fertility between treatments. So far, milking three times per day has not given a more persistent lactation compared with milking two times a day. Some cases of salty taste of milk have been noticed.
Article
Some years ago, systematic research was initiated to improve quantitative insight into the economic impact of diseases and disease control in livestock. This paper deals with the financial loss at farm level caused by reproductive failure in dairy cattle. Economic calculations concerning the calving interval of cows which differ in age, relative production level and persistence of milk production during lactation were made. On average, an optimal interval of 1 year or less was established, while the loss per day lengthening of the interval (norm-loss) amounted to 1–2 Dutch guilders (Dfl.). Also, 676 norm-losses due to forced replacement because of reproductive failure were determined, dependent on age and relative production level of the culled cow and average herd life of the farm. On average, this norm-loss was determined to be almost Dfl. 500 per culled cow. Based on 71 farms in an investigation in the province of Overijssel, total loss per farm was determined, using the calving interval data, forced replacement data and norm-loss rate described above. On average, the calculated loss amounted to Dfl. 63 per cow per year, of which Dfl. 35.50 resulted from sub-optimal calving interval and Dfl. 27.50 from forced replacement due to reproductive failure. Costs for veterinary treatment and drugs were not included in these elements. Total loss due to reproductive failure was estimated to average about Dfl. 80 per cow per year, which equals about 2% of the gross production value or 10% of an average farmer's income.Finally, considerable differences in loss between farms have been determined. The difference between the 20% of farms with the highest and the 20% of farms with the lowest calculated loss is even more than the average loss. Thus improvment may be achieved on many farms, e.g., with the help of a herd health programme.
Article
Value of days open was estimated by budgeting simulation of a commercial herd situation for Holstein cows of alternative milk yields with varying calving intervals. Values for days open were differences of income over feed cost per cow per day among alternative calving intervals of 12, 13, and 15 mo. Producing abilities for milk of cows corresponding to a 13-mo calving interval were 5900, 6800, 7700, and 8600 kg 3.5% milk per 300-day lactation. Conditions of herd management were a fixed policy of 65 days dry, herd size of 120 cows, group feeding with income-maximizing rations solved by linear programming, and a herd age structure of 30% of cows <36 mo and 70% of cows ⩾ 36 mo.Effect was little on annual income over feed cost in the short run for modest increases or decreases of calving interval. Depending on milk producing ability, minor positive or negative differences occurred by increasing calving interval from 12 to 15 mo. However, there was a positive value per day open (.21to.21 to .40) for all milk producing abilities when calving interval was increased from 12 to 13 mo and a consistently negative value per day open (−.04to.04 to −.23) when it was increased from 13 to 15 mo. Thus, the 13-mo calving interval appears to be close to optimal. Costs associated with changes in either direction from 13 mo were small enough not to be a major management issue when cows were grouped and fed according to milk yield and when dry period was 65 days.
Article
Influences of days open present lactation, days open previous lactation, and days dry previous lactation were fit simultaneously to determine their effects on measures of yield, which were fat-corrected milk, milk, and milk fat, all adjusted to a 305-d mature equivalent basis. Best linear unbiased estimates were obtained. Multiparity analyses were conducted using a model in which later parity records could be compared with more unselected first parity records. Additional parity information made little difference in the influence of previous days dry and previous and present days open on yield. As present days open increased from 20 to 300 d, lactation yields for FCM, milk, and milk fat increased approximately 1250, 1350, and 45 kg. As previous days open increased from 20 to 300 d, lactation yields for FCM, milk, and milk fat increased approximately 625, 650, and 25 kg. Cows dry 60 to 69 d gave the most milk the following lactation. Cows dry less than 40 d produced much less milk the next lactation. Heritability estimates for previous days dry were less than 7%. Multiplicative adjustment factors were developed to adjust lactation yield records for the largely environmental effects of days open and days dry.
Article
Length of open period affected annualized yield [(total lactation yield/calving interval) 365]. Yield was maximum with more days open for low, as opposed to high, peak production and for primiparous, as opposed to multiparous, cows. Interactions with days open were not found for mean herd production or cow production relative to the herd mean. Number of days open for maximum yield was similar for milk, fat, and economically fat-corrected milk [.67 kg milk + 10 kg fat]. Correction factors were derived by smoothed least square means of days open classes. Additive adjustment factors were more appropriate than multiplicative adjustment factors. Records adjusted for days open were not able to predict the following lactation yield significantly better than unadjusted records. Cumulative yield of current and following annualized lactations, including the contribution of the calf expressed in units of milk production, was greatest at 117 and 98 days open for primiparous and multiparous cows. For cows with high peak production maximum yield was with 12 to 14 fewer days open than for cows with moderate peak. Conception prior to 2 mo postpartum had an adverse effect on cumulative yield.
Article
Factors which positively or adversely affect the response of cow groups to different planned conception periods were analyzed and quantified. Cows were randomly assigned to groups for breeding at postpartum intervals of 35 to 59, 60 to 90 and 120 to 150 days in a research herd, or 60 to 90 and 120 to 150 days in a cooperating commercial herd, with a planned preceding dry period of 60 days in both herds. Breeding at 35 to 59 and 60 to 90 days post partum resulted in a lower conception rate among multiparous cows but had no effect on primiparous cows. Genital disorders such as metritis, retained placenta, vulva inflammation and vaginitis, did not affect the start of luteal activity or length of the subsequent cycles, but caused a significant delay of the first behavioral estrus and, consequently, a delay of the first insemination in the earlier breeding groups. About 30% of the cows in the different categories were inseminated three or more times and were considered to be repeat breeders. Response rates (number of cows conceiving on time/number assigned) in the later breeding group improved due to higher submission rates (number of cows submitted on time/number assigned), and the conception rates were higher (number of cows conceiving on time/number submitted). The rates in all groups were adversely affected by repeat breeding and genital disorders. The latter delayed the first insemination and the conception rate.
Effects of interval to first service on reproduction, lactation and culling in dairy cows Results of an integrative computer program of fertility and production data from AI cattle population. Proceed-ingsoftheTenthInternationalCongressonAnimalReproduction and Artificial Insemination
  • D S Harrison
  • C E Meadows
  • L J Boyd
  • J H Britt
Harrison, D. S., C. E. Meadows, L. J. Boyd, and J. H. Britt. 1974. Effects of interval to first service on reproduction, lactation and culling in dairy cows. J. Dairy Sci. 57:628. (Abstr.) Heimann, M. 1984. Results of an integrative computer program of fertility and production data from AI cattle population. Proceed-ingsoftheTenthInternationalCongressonAnimalReproduction and Artificial Insemination. Vol. 1 Urbana, IL
The optimal time for cows to conceive
  • A Harel
  • J Wagner
  • M Zohar
  • Y Pozin
Harel, A., J. Wagner, M. Zohar, and Y. Pozin, 1989. The optimal time for cows to conceive. Cheker Vemaas. (in Hebrew) 11:51–58
A comparison of cows with various open days, milk production, persistence and different calving seasons and its economic impact
  • Remer
Remer, I. 1987. A comparison of cows with various open days, milk production, persistence and different calving seasons and its economic impact. Meshek Habakar Vehachalav. (in Hebrew) 210:53–58.
Statistics, Version 6 Edition
  • Users Guide
SAS, Users Guide: Statistics, Version 6 Edition. 1990. SAS Inst., Inc., Cary, NC.
Results of an integrative computer program of fertility and production data from AI cattle population
  • Heimann
Heimann, M. 1984. Results of an integrative computer program of fertility and production data from AI cattle population. Proceedings of the Tenth International Congress on Animal Reproduction and Artificial Insemination. Vol. 1 Urbana, IL.
Extended calving intervals, BST may be profitable
  • D M Galton
Galton, D. M. 1997. Extended calving intervals, BST may be profitable. Feedstuffs (13/10/97) pp. 11–13.
The cost of an open day: data from the Northern Golan dairy
  • Sadeh
Sadeh, E. 1998. The cost of an open day: data from the Northern Golan dairy. Meshek Habakar Vehachalav. (in Hebrew) 269:31–33.
The optimal time for cows to conceive
  • Harel
Effects of interval to first service on reproduction, lactation and culling in dairy cows
  • Harrison