Milk Production Of Primiparous Cows Research Articles

Assessing Transition Cow Management in Dairy Cows for Improved Health, Milk Production, Pregnancy and Culling Outcomes

Understanding of the social environment has the potential to benefit dairy cow welfare and production. Our aim was to evaluate the associations of stocking density, calving density, days spent in a pre-partum group before calving (days spent in close-up, DCU) and the number of days from a pen filling event (addition of new cows to the pre-partum pen) on early-lactation health, production, pregnancy and culling outcomes in dairy cows. Data were gathered from 2780 cows in 2 herds. Herd management and reproductive records were analyzed for cows receiving treatment in the first 30 d of lactation (days in milk, DIM) for clinical mastitis, reproductive tract disease, ketosis, milk fever and displaced abomasum. Principal component analysis was used to account for the relationship between gestation length (GL) and DCU and their association with early lactation disease, milk production, pregnancy and culling outcomes. The effect of stocking density, the number of days from a pen filling event to calving and the calving density experienced by a cow in her week of calving was also evaluated. Causal inference was used to correct for confounding bias due to farm identity. The odds of disease in the first 30 DIM increased with stocking density before calving. A quadratic association was found between the first principal component (PC1), representing the combined effect of GL and DCU, and the odds of disease in multiparous cows only. Early lactation milk production and 305 d milk production in multiparous cows increased with PC1 score. Quadratic relationships were found between stocking density at d 8 to 2 before calving with both early lactation and 305 d milk production in multiparous cows but no associations were found in primiparous cows. Calving density showed a quadratic association with 305 d milk production in primiparous cows. The number of days from the last pen filling event to calving was not associated with changes in milk production. Disease occurrence was negatively associated with both early lactation and 305 d milk yield in multiparous cows but only with early lactation milk production in primiparous cows. The occurrence of disease was associated with a delayed time to pregnancy only in primiparous cows while both disease and being in lactation group ≥ 3 were negatively associated with time to pregnancy in multiparous cows. Week 4 milk (W4MK) was positively associated with reduced time to pregnancy in multiparous cows. For primiparous cows, increasing age at calving was associated with increased culling risk, while being in lactation group ≥ 3 was associated with increased culling risk in multiparous cows. Culling risk decreased with increasing W4MK in all cows. These results suggest that gestation length, time spent in close-up and stocking density are important factors influencing disease incidence in early lactation and subsequent lactation performance but had differing effects on primiparous versus multiparous cows. A better understanding of how pre-partum management factors influence postpartum health and milk production can help farms to plan facilities and organize the day-to-day management of cows and will assist in improving cow welfare and productivity.

Produção leiteira de vacas primíparas de acordo com o sexo da cria

Milk production in Brazil occupies the fourth position in the world ranking, with milk corresponding to one of the six essential products for Brazilian agriculture. The present study aimed to analyze the influence of the calf's sex at first calving on milk production (kg/milk/lactation) of cows. Using data from 43 bovine females, in which they were divided into two groups: Group I (male calving primiparous cows – MCPC) and Group II (female calving primiparous cows – FCPC). Subsequently, the data collected regarding milk production (kg of milk/lactation) were subjected to the normality test and analysis of variance, using the Tukey test. And the statistical analyses were performed using the public domain SISVAR 5.6 software. Dairy production of female calving primiparous cows (8,635.5) showed higher milk production (P < 0.05) than male calving primiparous cows (7,415.5), demonstrating in general aspects the existence of a positive effect of the sex of the calf in the milk production of primiparous cows. In conclusion, the sex of the calf creates an influence on milk production in the first lactation, where female calving primiparous cows tend to produce more milk.

Relationships among lying and standing behaviour, body condition score and milk production in primiparous cows

The aim of this study was to examine the time budgets of 20 lactating primiparous Italian Holstein cows and to determine the relationships between lying and standing behaviour, milk production and Body Condition Score in the first stage of lactation. Parturition period ranged from 15 September to 31 March and in the first seven lactation days all cows were equipped with individual 3-axes acceleration and angular displacement loggers, throughout 150 days for lying and standing behaviour measuring. Body Condition Scores (BCS) were estimated weekly, while milk production (in both morning and evening milking) and humidity and temperature air data were collected daily. Average individual milk yield was 27.3 ± 6.24 kg/d and milking time was 4.95 ± 1.94 min. Individual BCS was on average 3.46 ± 0.30 and standing daily time was 13.5 ± 2.26 h/d. Primiparous cows with BCS at parturition <3.25 quite regained BCS after 20 weeks of lactation, but produced on average 2.3 kg/d (p < .001) less than the other cows. Primiparous cows with standing time <14 h/d in the first 21 days of lactation showed higher BCS than the others cows (+0.11 on average, p < .001), but did not produce more milk (+0.1 kg/d, p = .25) on average and showed smaller Linear Score (logarithm transformation of milk somatic cell count) than other cows. Primiparous cows with standing time <14 h/d had higher number of lying bouts and less minutes between two lying bouts, probably due to a higher cow activity to feeding. Multiple regression on milk production showed a low effect of standing time, but primiparous cows lost 0.34 kg/d (p < .05) for each standing hour. HIGHLIGHTS Primiparous cows with standing time <14 h/d in the first 21 days of lactation showed higher BCS than the others cows Primiparous cows with standing time <14 h/d showed smaller somatic cell count Primiparous cows lost 0.34 kg/d for each standing hour

Effects of reduced in utero and post-weaning nutrition on milk yield and composition in primiparous beef cows

Development and long-term retention of replacement beef females in a semi-arid environment are of a major concern for extensive livestock producers. Furthermore, the demand of not only producing a thriving, healthy calf, but having sufficient milk to support that first calf is essential. To address this issue, we conducted a 3-year study measuring milk production and milk constituent yields in primiparous beef heifers (n=48; 16/year reared under two different feeding regimens) raising steer calves. Cows received 1.8 or 1.2 kg/day winter supplementation for ~80 day before parturition and their heifer calves were then randomly assigned to heifer development treatments that provided ad libitum (AL) or 80% (less than ad libitum (LAL)) of ad libitum feed post weaning. Heifers developed on the AL treatment also received 1.8 kg/day winter supplementation for life, whereas heifers developed on the LAL treatment received 1.2 kg/day winter supplementation for life. Milk production of primiparous cows was measured with a portable milking machine every other week from days 27 to 125 postpartum. Milk yield for the 125-day lactation period was calculated from area under the lactation curve approximated by trapezoidal summation. The ANOVA model included in utero winter nutrition, post-weaning heifer development treatment, year and their interaction. Heifers subjected to the AL treatment reached peak milk yield ~12.3 day later (P=0.02) than heifers receiving LAL treatment. In addition, an in utero nutrition×post-weaning heifer treatment×year interaction existed (P⩽0.04) for milk peak yield, average daily milk yield (kg/day) and nutrient composition (protein, lactose, fat, solids non-fat, g/day). These interactions manifest as changes in magnitude and rank across the 3 years of the study. Livestock production in extensive environments is subject to variations in seasonal precipitation patterns and quality and quantity of grazeable forage and these fluctuations have a large impact on milk yield. In summary, the gestational nutritional environment of a heifer’s mother may interact with the heifer’s nutrient consumption during post-weaning growth and the current year to trigger variation in year-to-year milk production.

Periconceptional Heat Stress of Holstein Dams Is Associated with Differences in Daughter Milk Production during Their First Lactation

The fertility of lactating Holstein cows is severely reduced during periods of heat stress. Despite this reduction in fertility, however, some inseminations conducted during heat stress result in successful pregnancies from which heifer calves are born. Many of these heifer calves are retained and raised to enter the milking herd as replacement animals. Heat stress experienced by these females around the time they were conceived may confer long-lasting effects that alter subsequent milk production capacity. The objective of this study was to examine the relationship between periconceptional heat stress and subsequent milk production of primiparous cows. National Dairy Herd Improvement Association data was obtained from Dairy Records Management Systems. Records included Holstein cows that had completed at least one lactation in one of three states with large populations of dairy cattle and which are known for having hot, humid summers: Georgia, Florida or Texas. Dates of conception were calculated by subtracting 276 d from the recorded birth date of each individual cow. Records for cows conceived within the months of June, July, and August were retained as heat stress-conceived (HSC) cows (n = 94,440); cows conceived within the months of December, January, and February were retained as thermoneutral-conceived (TNC) contemporaries (n = 141,365). In order to account for the effects of environmental conditions on total milk production for a given lactation, cows were blocked by season of calving (winter, spring, summer or fall). Adjusted 305-day mature-equivalent milk production was evaluated with a mixed model ANOVA using SAS, in which random effects were used to account for variability between herds. Of the cows that calved in the summer, fall and winter, TNC cows had higher milk yield than the HSC cows in all states. Interestingly, the cows that calved in the spring presented a unique relationship, with HSC cows producing more milk. Overall however, heat stress at the time of conception is associated with lower milk production during the first lactation. While this association does not prove cause and effect, it does provide justification for additional investigation into whether heat stress around the time of conception results in long-term, detrimental consequences for the conceptus.

Peripartum infection with Streptococcus uberis but not coagulase-negative staphylococci reduced milk production in primiparous cows

The effect of an intramammary infection (IMI) at calving on the milk yield of heifers during their first 200 d in milk (DIM) was estimated by comparing monozygotic twins, where one member had a naturally occurring IMI detected at the first milking after calving and the other twin did not. Data collected weekly over a full lactation for 29 twin pairs were used to estimate the effects of a peri-calving Streptococcus uberis IMI on milk yield and composition. Data for 19 twin pairs were used to estimate the effects of pericalving coagulase-negative staphylococci (CNS) IMI. A heifer with a Strep. uberis IMI produced 200kg (7%) less milk during the first 200 d of lactation compared with her uninfected twin, with significant differences evident throughout the 200-d period. Similar milk losses were recorded for heifers that developed CM or remained subclinical. An elevated milk SCC for infected heifers was only apparent for the first month (d 2–30), although SCC tended to remain high during the second (d 31–60) and third (d 61–90) months. Milk protein concentrations were greater in the Strep. uberis-infected twin over the 200-d period, whereas fat and lactose concentrations showed little change. An IMI caused by Strep. uberis was associated with a lower milk yield, whereas an IMI by CNS was not, despite CNS-infected twins having a higher SCC than their uninfected twin for the first 30 d of lactation.

Effects of postpartum uterine diseases on milk production and culling in dairy cows

The objective was to quantify the effect of postpartum uterine diseases on milk production and culling. Data from 2,178 Holstein cows in 6 herds enrolled in a randomized clinical trial were used. Milk production data from the first 4 Dairy Herd Improvement Association (DHIA) test-days and culling data from farm records were collected. Retained placenta (RP; ≥24 h after parturition) and metritis [≤20 d in milk (DIM)] were diagnosed by farm managers using standardized definitions. Farms were visited weekly and cows were examined at 35 and 56 (±3) DIM using endometrial cytology (cytobrush device), vaginal discharge scoring (Metricheck device), and measurement of cervical diameter by transrectal palpation. Diagnostic criteria for cytological endometritis (CYTO) and purulent vaginal discharge (PVD) were established based on a detrimental effect on subsequent reproduction. Statistical analyses were performed using linear mixed models, logistic regression models, and Cox proportional hazard models, accounting for the effects of experimental treatments and herd clustering. Milk production and culling were the outcomes. Primiparous and multiparous cows were modeled separately for milk production. Milk production of primiparous cows was unaffected by uterine diseases. The effect of metritis on milk production was variable over time in multiparous cows: it decreased production per cow by 3.7 kg at the first DHIA test, but was not different at later tests. Retained placenta decreased milk production by 2.6 kg/d in multiparous cows through the first 4 DHIA tests. The projected effects of metritis and RP in multiparous cows were reductions of 259 kg and 753 kg over 305 DIM, respectively; these effects were additive. Neither CYTO nor PVD affected milk production. Culling risks at 30 and 63 DIM were unaffected by RP and metritis. Culling hazard up to 300 DIM was unaffected by RP, metritis, CYTO, or PVD, whether or not pregnancy status, milk production, and displaced abomasum were accounted for. Uterine disease decreased pregnancy rate, which was a substantial risk factor for culling; however, if affected cows became pregnant they were not at greater risk of culling.

Performance and Feeding Behavior of Primiparous Cows Loose Housed Alone or Together with Multiparous Cows

Lactating Holstein cows (52 multiparous and 90 primiparous) were monitored over a period of 10 mo to observe effects of grouping primiparous cows (PPC) separately from multiparous cows (MPC) on performance, feeding behavior, feed intake, feed efficiency, and milk production of PPC. Cows were kept in 2 symmetrical pens each equipped with a robotic milking unit, 2 waterers, and 28 feeding spaces. Typically, 100 lactating cows were present at a time, thereby ensuring 1.78 cows per feeding place in each pen. One pen (PP) was composed exclusively of PPC whereas the other pen (PM) included 30% PPC and 70% MPC. Primiparous cows were evenly distributed to each pen by days in milk and daily milk production. As they calved, additional primiparous cows were assigned sequentially to each of the 2 treatment groups; multiparous cows calving during the study were allocated to the PM group. Both PP and PM groups were managed equally and were fed the same basal ration twice daily plus 3 kg/d of concentrate during milking. Individual eating behavior and feed consumption at each visit were monitored electronically. Milk production was recorded daily, and milk composition monthly. Observed arithmetic means and standard errors are presented but application to other management situations is limited because animals within pen were not independent. Total dry matter intake (18.7 vs. 18.1±0.9 kg/d) and milk production (25.9 vs. 25.6±0.8 kg/d) of PPC were similar in both the PM and PP groups, respectively. Primiparous cows in the PP group had numerically more visits to the robotic milking unit (3.26 vs. 2.68±0.15) and to the feed troughs (4.91 vs. 4.02±0.43), but apparently spent less time eating (2.72 vs. 3.22±0.1 h/d) than did PPC in the PM group. Differences in feed efficiency were low but PPC in the PP group had numerically higher feed efficiency at times through 200 d in milk. Alternative grouping strategies illustrate potentially important differential responses among primiparous cows that warrant further study.

Feeding intensity of pregnant heifers: Effect of feeding intensity during gestation on performance and plasma parameters of primiparous Ayrshire cows

The effect of different feeding intensity at two stages of gestation on performance of primiparous cows was studied in 40 pregnant Ayrshire cows. The feeding intensity was either medium (M) or high (H) in period 1 (2–6 months of pregnancy) or period 2 (7–9 months of pregnancy) resulting in treatments MM, MH, HM and HH. Before pregnancy all heifers were reared to gain 650 g/day. In period 1, heifers on H feeding intensity, grew significantly faster than heifers on M (844 vs. 638 g/day; SEM=18.9). Daily gains in period 2 were affected by feeding intensity in period 1 and were 710, 1042, 636 and 874 g on MM, MH, HM, and HH diets, respectively. The body weights at calving were 462, 498, 480 and 499 kg on MM, MH, HM and HH diet, respectively. Feeding intensity in period 1 had no effect on milk production, but H plane of nutrition in period 2 increased milk yield by approximately 11% (22.6 vs. 20.3 kg/day, P<0.004). Medium feeding intensity in period 1 increased postpartum DMI, and decreased postpartum mobilization of body reserves. Mobilization was positively correlated with BCS at calving ( r=0.48; P<0.003) and with plasma free fatty acid ( r=0.73; P<0.0001) and β-hydroxybutyrate concentrations ( r=0.69; P<0.0001). Prepartum treatments had no effect on postpartum plasma growth hormone (GH) or prolactin concentration, but high feeding intensity in period 2 decreased insulin (INS) concentration postpartum. No relationships were found across treatments between milk yield and prepartum plasma hormone concentrations, but a positive correlation was found between milk yield and postpartum GH and GH/INS. The results show that high compared with medium feeding intensity during the first two trimesters of gestation does not improve milk production of primiparous cows. Instead, during the last trimester a high feeding intensity is required for maximum milk yield.