Reproductive Performance Of Cows Research Articles

Effects of Season Variation on Water, Feed, Milk Yield and Reproductive Performance of Dairy Cows in Smallholder Farms in Eastern Africa

Aim: The smallholder dairy industry in Eastern Africa continues to be characterized by seasonality driven milk fluctuations and reproductive performance of dairy cows. In this review, we present important effects of changes in seasons on water, feed quantity and quality, milk yield and reproductive performance of dairy cows in smallholder dairy farms.
 Methods: We considered peer-reviewed publications from 1990 to 2019, and extracted any information pertaining to the effects and intensity of changes in seasons and implications on water, feed quality and quantity, milk yield and reproductive performance.
 Results: Seasonal variation in rainfall, characteristic of the East Africa region, is strongly reflected in cropping and feeding calendars. Hence, 305-days lactation milk production per cow in Eastern Africa ranges from 850-3150 kg/cow/year, which has not increased, partly because of lack of improvement in nutrition and management, but also due to slow genetic selection of breeds that matches available feed to milk yield and reproductive performance. High milk fluctuations arise mostly because of farmers’ dependence on rainfall for feed production and rarely make provisions for preserving fodder for the dry season, as there isn’t adequate forage (fodder and pasture) even during the wet season.
 Conclusion: For the smallholder dairy farmers to remain competitive, it is important to increase the dairy value chain capability to manage implications of changes in seasons on milk yield and reproduction. Therefore, in order to overcome the current seasonal changes, we have discussed technological interventions in adoption of practical, sustainable farmer-led strategies for optimizing water and feed production, milk yield and reproductive performance in Eastern Africa. We have also identified knowledge gaps where research is needed to guide dairy value chain stakeholders on how to ameliorate current seasonal changes or that we expect will occur in the future.

Comparison of FTAI and Natural Service Breeding Programs on Beef Cow Reproductive Performance, Program Cost and Partial Budget Evaluation

The study compared a natural-service breeding (NSB) program to a single fixed-time artificial insemination (FTAI) program on beef cow reproductive efficiency, breeding costs and partial budget evaluation. Eighty Black Angus lactating beef cows (5-6 yrs of age; n = 80; BW = 599.4±78.6 kg) were randomly assigned by age, days postpartum to either FTAI (FTAI cow) or NSB (NSB cow) breeding program. The FTAI cows received a CIDR for 7 d and 100 μg (2 mL) i.m. injection of GnRH, following this 25 mg (5 mL) i.m. of PGF2α i.m. with CIDR removed. Then a second 25 mg (5 mL) i.m. injection of GnRH approximately 66 h (d 10) after initial injection to ensure luteal regression, and artificially inseminated with semen by a trained technician. The NSB cows were exposed to bulls at a bull:cow ratio of 1:25 for a 63 d breeding season. Results indicated that a NSB program can be a lower cost ($85 vs. $123) compared to FTAI program on a per cow basis. If improvements in conception rate, calf weaning rate, and total 205 d adjusted wean weights are incorporated, a partial budget analysis reveals FTAI can increase net profit by $284 per cow.

Effects of Area Specific Mineral Mixture (ASMM) Supplementation on Production and Reproductive Parameters of Crossbred and Desi Cows: A Field Study

A field study was conducted to evaluate the effects of supplementation of area specific mineral mixture (ASMM) on the production and reproductive performance of cows. 16 animals of both crossbred and desi cows each were evaluated for production and reproduction performances. In all treatment groups (n=8), ASMM was supplemented @ 50 g cow-1 day-1 and @ 30 g cow-1 day-1 to crossbred and desi cows respectively. The control groups (n=8) of each experiment were without ASMM supplementation. In case of productive performance, milk production and milk composition parameters were studied for a period of 90 days of lactation where as dissolution of common reproductive disorders were screened for reproductive performance. Average daily milk yield in the crossbred cows supplemented with ASMM on 90th day and 120th day were 7.72 ± 0.19 L cow-1 and 7.52 ± 0.12 L cow-1 in contrast to 5.96 ± 0.14 L cow-1 and 5.63 ± 0.21 L cow-1 in the control group. Similarly average daily milk yield in the desi cows supplemented with ASMM on 90th day and 120th day were 4.17 ± 0.09 L cow-1 and 3.70 ± 0.08 L cow-1 in contrast to 3.06 ± 0.03 L cow-1 and 2.92 ± 0.04 L cow-1 in the control group. No significant supplemental effects on the milk composition parameters in all the groups were found. First postpartum estrus and number of AI per conception were lesser but conception rates were higher in both crossbred and desi treatment groups compared to respective control groups. It can be concluded that continuous supplementation of area specific mineral mixture enhanced the productive and reproductive efficiency of both crossbred and desi cows.

Relationship between body condition score, blood metabolites, oxidative stress and reproductive performance in transition dairy cows

The aim of the current study was to investigate the relationship between prepartum body condition score (BCS), blood metabolites (Glucose, BHB), oxidative stress (MDA, GSH-Px) in transition period and some reproductive parameters in Holstein dairy cows. 50 cows were divided into two groups (low BCS, n=25, BCS = 2.75-3.0 and adequate BCS, n=25, 3.25 ≤ BCS ≤ 3.75) according to BCS on the 21 st day before expecting calving. BCS was also recorded at 0 and +21 days after calving. Blood samples collected at -21, 0 and +21 days from calving for MDA and GSH-Px analysis as well as at -21, +14 and +21 days of postpartum for glucose and BHB. Reproductive parameters obtained from farm records were also collected. MDA concentrations were higher in group of low BCS compared to group of adequate BCS at -21 and 0 d related to calving (p<0.05). GSH-Px activity was lower in group of low BCS than adequate one during the transition period (p<0.05). Low BCS group also showed higher concentrations of BHB at +14 and +21 days after calving. During the transition period, low BCS group had lower glucose concentrations compared to adequate one (p<0.05). Adequate BCS group of cows showed shorter intervals of calving to first estrus (p<0.01) and calving to conception (p<0.01). In conclusion, cows with lower BCS at the prepartum period had worse metabolic and oxidative balance during the transition period. This situation also causes worse reproductive performance in cows.

Relationship between body condition score, blood metabolites and oxidative stress in transition period and reproductive performance of dairy cows

The aim of the current study was to investigate the relationship between prepartum body condition score (BCS), blood metabolites (Glucose, beta-hydroxybutyrate; BHB), oxidative stress (Malondialdehyde; MDA, Glutathione peroxidase; GSH-Px) in transition period and some reproductive parameters in Holstein dairy cows. Fifty cows were divided into two groups [low-BCS = 2.75-3.0 (n=25); adequate-BCS = 3.25-3.75 (n=25)] according to BCS on the 21st day before expected calving. BCS was also recorded at 0 and +21 days after calving. Blood samples collected at -21, 0 and +21 days from calving for MDA and GSH-Px analysis as well as at -21, +14 and +21 days of postpartum for glucose and BHB. Data on reproductive parameters obtained from farm records were also collected. MDA concentrations were higher in group of low-BCS compared to group of adequate-BCS at -21 and 0 d related to calving (p&lt;0.05). GSH-Px activity was lower in group of low-BCS than adequate one during the transition period (p&lt;0.05). Low-BCS group also showed higher concentrations of BHB at +14 and +21 days after calving. During the transition period, low-BCS group had lower glucose concentrations compared to adequate one (p&lt;0.05). Adequate-BCS group of cows showed shorter intervals of calving to first estrus (p&lt;0.01) and calving to conception (p&lt;0.01). In conclusion, cows with lower BCS at the prepartum period had worse metabolic and oxidative balance during the transition period. This situation also was associated with worse reproductive performance in cows.

Seasonal changes in the reproductive performance in local cows receiving artificial insemination in the Pursat province of Cambodia.

ObjectiveThe present study aimed to survey seasonal changes in reproductive performance of local cows receiving artificial insemination (AI) in the Pursat province of Cambodia, a tropical country, to investigate if ambient conditions affect the reproductive performance of cows as to better understand the major problems regarding cattle production.MethodsThe number of cows receiving AI, resultant number of calving, and calving rate were analyzed for those receiving the first AI from 2016 to 2017. The year was divided into three seasons: cool/dry (from November to February), hot/dry (from March to June), and wet (from July to October), based on the maximal temperature and rainfall in Pursat, to analyze the relationship between ambient conditions and the reproductive performance of cows. Body condition scores (BCS) and feeding schemes were also analyzed in these seasons.ResultsThe number of cows receiving AI was significantly higher in the cool/dry season than the wet season. The number of calving and calving rate were significantly higher in cows receiving AI in the cool/dry season compared with the hot/dry and wet seasons. The cows showed higher BCSs in the cool/dry season compared to the hot/dry and wet seasons probably due to the seasonal changes in the feeding schemes: these cows grazed on wild grasses in the cool/dry season but fed with a limited amount of grasses and straw in the hot/dry and wet seasons.ConclusionThe present study suggests that the low number of cows receiving AI, low number of calving, and low calving rate could be mainly due to poor body condition as a result of the poor feeding schemes during the hot/dry and wet seasons. The improvement of body condition by the refinement of feeding schemes may contribute to an increase in the reproductive performance in cows during the hot/dry and wet seasons in Cambodia.

Effects of various mastitis treatments on the reproductive performance of cows

BackgroundThe purpose of the study described here was to evaluate the effects of different supportive treatments - such as antioxidants, immunomodulators, and nonsteroidal anti-inflammatory drugs (NSAIDs) - in mastitic cows treated with intramammary antibiotics on the efficacy of mastitis therapy and fertility indices. Fertility indices, including time to first insemination, conception rate, time between calving and conception (open days), and number of services per conception (insemination index), were evaluated for 300 dairy cows. Sixty cows without apparent clinical signs of mastitis were assigned 100 days after calving to a Control group. Another 240 cows with clinical mastitis were systematically divided into four experimental groups (I–IV) of 60 cows each. All mastitic cows were treated with approved intramammary antibiotics in recommended doses. Cows in Group I were treated with intramammary antibiotics only. Cows in Groups II, III, and IV, received intramammary antibiotic therapy and a single injection with antioxidants, an immunomodulator (lysozyme dimer), or an NSAID (flunixin meglumine), respectively.ResultsThe lowest treatment efficacy of mastitic quarters and cows was noted in Group I (51.6 and 53.3%; p > 0.05). The best recovery rate was noted in Group II (63.3 and 66.7%; p > 0.05), followed by Group III (58.3 and 60.9%) and Group IV (58.3 and 58.0%; p > 0.05). The above data did not differ statistically (p > 0.05). The animals with mastitis (Groups I–IV) showed prolonged time to first insemination, more open days, higher insemination index, and lower conception rate than the control cows (p < 0.05). The conception rate of healthy cows and of successfully treated cows was insignificantly lower than that of cows required prolonged antibiotic therapy. Supportive treatments improved the mastitis recovery rate compared with intramammary antibiotics only. The efficacy of mastitis treatments affected the reproduction indices: in cows requiring prolonged treatment with antioxidants, a shorter time to first insemination was needed than in other groups (p < 0.05). Fewer days open were observed between the group with antioxidants and the control group (p < 0.05).ConclusionsClinical mastitis negatively affects reproductive indices (days open, pregnancy rate after first AI, NSC) in dairy cows. Different types of supportive medicine, such as antioxidants (vitamin C and E, and β-carotene), lysozyme dimer, or NSAID can be useful in improving fertility in mastitis cows treated with antibiotic only. It has been proven that each supportive treatment improved antibiotics efficiency and the antibiotic combined with the antioxidants was the most effective treatment.

Reproductive performance of northern Australia beef herds. 2. Descriptive analysis of monitored reproductive performance

A population-based epidemiological study was conducted between 2007 and 2011 and involved 78 northern Australian commercial beef-breeding herds and in excess of 56 000 cattle concurrently monitored. Cow reproductive performance was described from the biannual assessment of fetal age and lactation status. Both novel and well established measures of performance were used within four broad country types and included the following: percentage of lactating cows pregnant within 4 months of calving; percentage of cows pregnant within an approximate 12-month reproductive cycle (annual pregnancy); fetal and calf loss between confirmed pregnancy and weaning; percentage of cows contributing a calf at weaning and percentage of non-pregnant females retained for re-mating. The results from the present study described the variation in reproductive performance of commercial beef herds across northern Australia and defined typical and achievable levels of performance. The results from the study suggest that a weaning rate of 66% is a more realistic target level of performance for the Northern Forest, while weaning rates of at least 75–80% are realistic for other country types. Female-cattle performance was much lower in the Northern Forest than in the other country types. In absolute terms, there were 15–20% fewer surviving mated cows contributing a calf at weaning in an annual production year and ~4% more missing pregnant cows, which was associated with the ~20% higher retention of non-pregnant cows for re-mating. The reproductive performance of herds varied substantially among and within country types, with a 20–30% variation in reproduction rates and 5–15% variation in fetal and calf loss for half of the herds in all regions. Further analyses were performed and identified the major causes of this variation and are reported in subsequent papers within this series. The results from the present study appear to suggest that substantial opportunities to increase the reproductive performance of northern beef herds exist, providing that the causes of this variation are able to be identified and alleviated.

Effects of in-feed clinoptilolite treatment on serum metabolic and antioxidative biomarkers and acute phase response in dairy cows during pregnancy and early lactation

The objective of this study was to evaluate the effects of in-feed clinoptilolite (CPL) on serum metabolic and antioxidative biomarkers, acute phase proteins and reproductive performance in cows during pregnancy and lactation. A total of 78 Holstein-Friesian cows were randomly assigned into two groups: the treatment group, cows fed CPL (n = 38) which received 50 g of powdered CPL twice a day from day 180 before parturition to day 60 postpartum; and the control group (n = 40). Blood samples were taken on days 180, 90, 60, 30 and 10 before parturition, on day of calving and on days 5, 12, 19, 26, 33, 40 and 60 postpartum, and were analysed for metabolic biomarkers: glucose, triglycerides, total cholesterol, high density lipoprotein cholesterol, non-esterified fatty acids, beta-hydroxybutyrate (BHB), antioxidative biomarkers and acute phase proteins: paraoxonase-1 (PON1), apolipoprotein A-I, haptoglobin (Hp) and serum amyloid A (SAA). CPL supplementation increased concentration of glucose and significantly decreased (P < .05) level of BHB during puerperium. The SAA concentration in CPL-fed cows was significantly decreased (P < .05) on days 33, 40 and 60 postpartum as well as Hp concentration on days 0 and 12 postpartum. The results of this study suggest that the CPL-fed cows may have improved metabolic status due to the tendency of greater glucose levels and decreased BHB values during early lactation. In addition, acute phase response was lower (P < .05) in CPL-fed cows. Such an outcome might be attributed to the effect of dietary CPL on intensity and severity of the negative energy balance and inflammatory response in dairy cows.

Reproductive performance of cows and genetic correlation with weight gains and principal components of traits used in selection of Nelore cattle

The objectives of this study were to estimate heritability and genetic correlations for female traits (HR: heifer rebreeding; NC53: number of calves at 53 months of age; HP: heifer pregnancy at 18 months of age; AFC: age at first calving) and weight gains (BWG: from birth to weaning; WYG: from weaning to yearling) in Nelore cattle. Additionally, the relationship of these female traits with four principal components (PC) of predicted breeding values for traits used as selection criteria in this population was evaluated (i.e., weaning and postweaning weight gain, visual scores of conformation, finishing precocity and muscling, and scrotal circumference). The PC were obtained in previous analyses using phenotypic data from 600,132 animals. Low to moderate heritability were estimated for the females traits (HR: 0.12 ± 0.01; NC53: 0.13 ± 0.01; HP: 0.33 ± 0.02; AFC: 0.20 ± 0.01) and weight gains (BWG: 0.24 ± 0.01 and 0.14 ± 0.04 for direct and maternal effects; WYG: 0.21 ± 0.01). The genetic correlations between female traits were favorable, with positive and high estimates between HR, NC53 and HP (0.83 ± 0.03–0.94 ± 0.01) and negative between HR, NC53 and HP with AFC (-0.66 ± 0.02–−0.98 ± 0.01). Heifer rebreeding showed a moderate and negative genetic association with BWG and a positive association with WYG. The genetic association of NC53 with weight gains was positive and favorable (0.31 ± 0.03 with BWG and 0.42 ± 0.04 with WYG). Low genetic correlations were obtained between weight gains with HP and AFC. The first PC, with positive coefficients for all traits, showed a low and favorable genetic association with HP and AFC, but zero with HR and NC53. The second PC, which contrasted weaning and yearling traits, was genetically associated with HR (−0.17 ± 0.03). The third PC, related to early maturity, showed low and negative (favorable) genetic correlations with HR, NC53 and HP (−0.09 ± 0.01–−0.14 ± 0.02) and a positive genetic association with AFC (0.13 ± 0.01). The combination PC showed positive and low genetic correlations with HR and HP (0.12 ± 0.03 and 0.19 ± 0.02, respectively), and negative with NC53 and AFC (−0.08 ± 0.01 and −0.18 ± 0.02, respectively). In general, no relevant genetic antagonism was observed between female traits and weight gains; thus, simultaneous genetic improvements in these traits are possible. The selection based on principal components to achieve a particular breeding objective can provide low or no genetic gains in female traits. Our results thus reinforce the need to use reproductive traits measured directly in females as selection criteria to obtain improvements in sexual precocity and longevity of beef cows.

23 Timing of concentrate supplementation during late gestation impacts calf pre-weaning growth, but not reproductive performance of Bos indicus-influenced cows

Abstract This study evaluated the effects of timing of dried distillers grains (DDG) supplementation during late-gestation on performance of Bos indicus-influenced cow-calf pairs. At about 84 d before calving (d 0), 84 mature Brangus cows were stratified by BW and BCS (422 ±42 kg; BCS = 5.0 ± 0.14) and assigned randomly to bahiagrass pastures (14 cows/pasture). Treatments were assigned randomly to pastures (2 pastures/treatment) and consisted of no prepartum supplementation (CON), 1 kg/d of DDG from d 0 to 84 (LATE84; 84 kg of DM/cow); or 2 kg/d of DDG from d 0 to 42 (LATE42; 84 kg of DM/cow). The respective weekly supplement amount was divided and offered into 3 feeding events (Monday, Wednesday, and Friday). Cow BCS were assessed on d 0, 45, 84 (calving), 140 and 224 (start and end of breeding season, respectively). Calf BW was collected at birth and weaning (d 346). Growth and reproductive data were analyzed using SAS MIXED and GLIMMIX procedures, respectively. Cow BCS from d 45 to 224 did not differ between LATE84 and LATE42 cows (P ≥ 0.20) but was always the least (P ≤ 0.05) for CON cows. Calving date, calf birth BW, and percentage of pregnant cows on d 283 did not differ (P ≥ 0.19) among treatments. Calf pre-weaning ADG and BW at weaning did not differ (P ≥ 0.58) between LATE42 and CON calves, but LATE84 calves tended to have the greatest pre-weaning ADG (P = 0.10; 0.88, 0.83, and 0.82 ± 0.02 kg/d, respectively) and BW at weaning (P = 0.10; 263, 254, and 252 ± 4.4 kg, respectively). Therefore, timing of prepartum DDG supplementation did not impact cow reproductive performance. However, calf pre-weaning growth tended to be enhanced when cows received longer vs. shorter or no periods of prepartum DDG supplementation

151 Timing of concentrate supplementation during late gestation impacts calf pre-weaning growth, but not reproductive performance of Bos indicus-influenced cows

Abstract This study evaluated the effects of timing of dried distillers grains (DDG) supplementation during late-gestation on performance of Bos indicus-influenced cow-calf pairs. At about 84 d before calving (d 0), 84 mature Brangus cows were stratified by BW and BCS (422 ±42 kg; BCS = 5.0 ± 0.14) and assigned randomly to bahiagrass pastures (14 cows/pasture). Treatments were assigned randomly to pastures (2 pastures/treatment) and consisted of no prepartum supplementation (CON), 1 kg/d of DDG from d 0 to 84 (LATE84; 84 kg of DM/cow); or 2 kg/d of DDG from d 0 to 42 (LATE42; 84 kg of DM/cow). The respective weekly supplement amount was divided and offered into 3 feeding events (Monday, Wednesday, and Friday). Cow BCS were assessed on d 0, 45, 84 (calving), 140 and 224 (start and end of breeding season, respectively). Calf BW was collected at birth and weaning (d 346). Growth and reproductive data were analyzed using SAS MIXED and GLIMMIX procedures, respectively. Cow BCS from d 45 to 224 did not differ between LATE84 and LATE42 cows (P ≥ 0.20) but was always the least (P ≤ 0.05) for CON cows. Calving date, calf birth BW, and percentage of pregnant cows on d 283 did not differ (P ≥ 0.19) among treatments. Calf pre-weaning ADG and BW at weaning did not differ (P ≥ 0.58) between LATE42 and CON calves, but LATE84 calves tended to have the greatest pre-weaning ADG (P = 0.10; 0.88, 0.83 and 0.82 ± 0.02 kg/d, respectively) and BW at weaning (P = 0.10; 263, 254 and 252 ± 4.4 kg, respectively). Therefore, timing of prepartum DDG supplementation did not impact cow reproductive performance. However, calf pre-weaning growth tended to be enhanced when cows received longer vs. shorter or no periods of prepartum DDG supplementation

Late embryonic losses in supplemented grazing lactating dairy cows: Risk factors and reproductive performance

The main objective of this study was to evaluate the risk factors for late embryonic loss (LEL) in supplemented grazing dairy cows. Additional objectives were to assess the incidence of LEL and its association with the reproductive performance of cows. A data set containing productive, reproductive, and health records of 13,551 lactations was used. A retrospective case-control study involving 631 cows with LEL (cases) and 2,524 controls (4 controls per case within each study year) was run. A case of LEL was defined when the embryo had no heartbeat or there was evidence of detached membranes or floating structures including embryo remnants by ultrasonography (US) at 28 to 42 d post-artificial insemination (AI), whereas a non-case was defined as a cow diagnosed with positive pregnancy by US 28 to 42 d post-AI and reconfirmed as pregnant 90 ± 7 d post-AI. Four controls per case were randomly selected from the non-cases with a temporal matching criterion (±3 d around the date of the fecundating AI of the case). Multivariable logistic models were offered with the following predictors: year of LEL (2011 through 2015), season of LEL (summer vs. fall vs. winter vs. spring), parity (1 vs. 2 vs. ≥3), uterine disease (UD), non-uterine disease (NUD), body condition score at parturition, body condition score at 28 to 42 d post-AI (BCS-LEL), days in milk (DIM), and daily milk yield (MY). Statistical significance was set at P < 0.05 and a tendency was set at P ≤ 0.10. We found that 4.7, 22, and 23% of cows had LEL, UD, and NUD, respectively. Cases tended to have higher daily MY than controls (32.5 vs. 31.8 kg); also, cases had much longer calving to pregnancy interval (226 vs. 118 d), lower hazard of pregnancy [hazard ratio = 0.39, 95% confidence interval (CI) = 0.35-0.43], and higher odds for non-pregnancy [odds ratio (OR) = 2.89, 95% CI = 2.37-3.54] than controls. We found that the odds for LEL increased with parity number (OR = 2.48, 95% CI = 1.99-3.08 for parity ≥3) and with BCS-LEL <2.50 (OR = 1.81, 95% CI = 1.33-2.47). Conversely, the odds for LEL decreased with BCS-LEL >3.00 (OR = 0.70, 95% CI = 0.53-0.91). The odds for LEL increased with UD (OR = 1.23, 95% CI = 1.01-1.49), NUD (OR = 1.24, 95% CI = 1.01-1.54), DIM (OR = 1.03, 95% CI = 1.00-1.05), and daily MY (OR = 1.14, 95% CI = 1.04-1.25) in univariable models only. Finally, the odds for LEL were not associated with year, season, DIM, and body condition score at parturition. In conclusion, LEL is associated with extended calving to pregnancy interval, and among its risk factors are parity number and BCS-LEL.

Postpartum Uterine Bacterial Contamination without Clinical signs in Rela-tion to Reproductive Performance in Dairy Cows

The study was performed to find out the relation between the uterine bacterial contaminations without clinical signs and postpartum (PP) reproductive performance of dairy cows. So that, uterine bacterial samples from postpartum dairy cows total (n = 44) were taken at 3rd, 15th and 30th day, and the bacterial count and score were applied. The animals were grouped to low, medium and high uterine bacterial contamination (15, 15, and 14 cows for each group respectively) according to score. Results revealed that uterine bacterial score (UBS) was decreased by the time in 3rd, 15th and 30th day (PP) for Low bacterial contamination group (5.73, 2.80, and 1.20 respectively), for Medium bacterial contamination group (7.80, 2.73, and 1.47 respectively), and for High bacterial contamination group (9.29, 6.57, and 2.21 respectively). Also, it revealed that there was a significant increase (P&lt;0.05) in the duration of lochia in High than Low and Medium bacterial contamination groups. At 3rd day (PP), uterine location in all cows was represented in the abdominal cavity, but at15th day (PP), uterine involution as reaching to its normal non pregnant position in pelvic cavity was delayed in High (50%) than Low (80 %,) and Medium (53.30%) UBS groups. Moreover, at 30th day, uterine location in all cows was represented in pelvic cavity. The first estrus (PP) was significantly shorter in Medium, Low than High UBS groups. The number of services per conception showed a significant increase in High than in Low and Medium UBS groups. Also, at the 90th day (PP), the conception rate was lower in High UBS group than Low UBS group and Medium UBS group. We conclude that there was a relation between postpartum uterine bacterial contamination without clinical signs especially high contamination and reproductive performance in cows.

Relationships between welfare and reproductive performance in French dairy herds

This study aimed to investigate the relationship between cow reproductive performance and welfare evaluated at the herd level using the Welfare Quality protocol. The 11 criteria, four principles (good feeding, good housing, good health and appropriate behavior, scale 0–100) and overall welfare category (excellent/enhanced/acceptable/not classified = poor welfare) were included as risk factors for calving to first service interval (CFSI) and calving rate (CR). The confounding factors cow breed, parity, season of calving and AI, calving to AI interval, rank of AI (1–3) and milk production were taken into account. The sample included 3951 AIs (2172 AI1, 1182 AI2, 597 AI3) in 124 French commercial dairy herds.Median CFSI was shorter for the cows bred in herds with a higher overall welfare category (median 75 and 76 days in enhanced and acceptable herds vs. 86 in poor welfare ones, P = 0.02). The scores for absence of injuries and expression of social behavior tended to be associated with CFSI (P < 0.10). Calving rate (34.5%) was not related to the overall welfare category. However, CR was positively related to the good housing score and a positive trend was observed with the scores for absence of prolonged hunger and absence of injuries. In conclusion, this study confirms a positive relationship between CFSI and welfare in dairy cows with no explicit links with specific aspects of animal welfare.

Production and reproduction performance of buffalo, crossbred and indigenous cows in different agro-climatic zones of Uttar Pradesh

The present study was undertaken to assess the production and reproduction performance of dairy animals among the farmers using mKisan services in different agro-climatic zones of Uttar Pradesh. A total of 225 farmers (45 each from five agro-climatic zones of UP) with their 301 buffaloes, 235 crossbred cows and 304 indigenous cows were considered. The study revealed that average daily milk yield, lactation length, lactation milk yield, peak milk yield, dry period, age at first calving, service period, services/ conception and calving interval for buffaloes were 5.7±0.6 L/day, 298±20 days, 1746.4±94 L, 8.7±0.5 L, 215±21 days, 1295±104 days, 174±15 days, 2.1±0.3 and 446±42 days, respectively, for crossbred cows, 7.2±0.5 L/day, 280±21 days, 2200.4±104 L, 11.0±0.4 L, 232±20 days, 1175±111 days, 179±18 days, 2.6±0.4 and 439±53 days, respectively and for indigenous cows, 3.8±0.4 L/ day, 193±18 days, 1180.8±83 L, 5.9±0.3 L, 165±15 days, 1548±94 days, 261±14 days, 2.5±0.5 and 314±43 days, respectively. The production and reproduction performance of dairy animals of Western zone and Mid-Western zone was significantly higher than Central Plain zone, North Eastern zone and Bundelkhand zone. Experience in livestock farming, accessibility of information sources, social relation &amp; participation and herd size were positively and significantly correlated (0.167–0.359) with performance of dairy animals at household level. Whereas knowledge about dairy farming and message utilization index were having highly significant and positive relation (0.548, 0.511) with performance of dairy animals at household level.

Inferior fertility and higher concentrations of anti-Müllerian hormone in dairy cows with longer anogenital distance

Anogenital distance (AGD), which is an indicator of prenatal androgen exposure, has been reported to have high variability and negative association with fertility in dairy cows. Prenatal exposure to androgens could influence the development of primordial follicles and size of ovarian reserve, which is related to reproduction. However, the relationship between AGD and size of ovarian reserve has not been studied. Therefore, the present study was conducted to determine the association between AGD and circulating anti-Müllerian hormone (AMH), as an indirect marker of ovarian reserve, and to evaluate serum AMH concentration and reproductive performance in dairy cows with short and long AGD. Anogenital distance was measured 28 to 32 d postpartum, and based on the median of AGD, cows were divided into 2 subsets including short (n = 43) and long (n = 43) AGD groups. Afterward, serum AMH was evaluated on the day of estrus in cows that were estrus-synchronized. Furthermore, reproductive data of dairy cows during the previous lactation period were collected from the herd database. Concentrations of serum AMH tended to be positively associated with length of AGD, and there was a tendency for higher serum AMH concentrations in the long (634.89 ± 74.52 pg/mL) than short (451.39 ± 45.92 pg/mL) AGD group (0.05 <P ≤ 0.10). There was a tendency for more days to first service, lower first service conception rate, and higher proportion of repeat breeders in long (99.95 ± 5.34 d, 30.23% and 32.56%, respectively) than short (89.07 ± 4.97 d, 48.84% and 16.28%, respectively) AGD cows (0.05 <P ≤ 0.10). Services per conception did not differ between short (2.30 ± 0.27) and long (2.93 ± 0.29) AGD cows (P > 0.05). Calving to conception interval was prolonged in long (194.30 ± 17.12 d) than short (147.14 ± 13.11 d) AGD cows (P ≤ 0.05). In conclusion, the present study revealed elevated serum AMH concentrations and poor reproductive performance in cows with longer AGD compared with cows with shorter AGD.

Reproduction Performance of Ongole Grade Cows and Its Crossbreds in Pacitan Regency, East Java Province, Indonesia

This study aimed to determine the reproduction performance of Ongole grade cows and its crossbreds in Pacitan district, East Java province, Indonesia including the age of first mating (AFM), the age of first calving (AFC), service per conception (S/C), postpartum oestrus (PPO), postpartum mating (PPM). The research method was a direct research conducted in the field and using survey method with purposive sampling. This research was conducted in 2010 using reproduction data on Ongole grade cows (PO) and its crossbreds. The crossbreds were LimPO (LimousinexPO) and SimPO (SimmentalxPO). During observation, this study used 35 heads of each breed. Data were analyzed descriptively. Reproduction performance analysis result of PO, LimPO, SimPO cows respectively obtained; 1) AFM were 1.86±0.39 years; 1.74±0.25 years; 1.79±0.28 years, 2) AFC were 2.95±0.44 years; 2.73±0.28 years; 2.72±0.29 years, 3) S/C were 1.71±0.87; 1.42±0.56; 1.55±0.66, 4) PPO were 4.14±1.23 months; 4.00±1.09 months; 4.63±1.16 months, 5) PPM were 5.27±1.54 months; 4.42±1.30 months; 4.63±1.57 months.

Growth and Reproductive Performance of Rangeland Beef-Cattle as Influenced by Controlled and Uncontrolled Populations of Horn Flies (Diptera: Muscidae).

A 4-yr study was conducted on native rangeland to assess the growth and reproductive performance of cows (Bos taurus) infested with naturally occurring seasonal populations of horn flies (Haematobia irritans). One hundred five Angus × Hereford cow-calf pairs were evaluated as a randomized complete block that was replicated across 4 yr. Cows were approximately 39 d postpartum at the beginning of each yearly trial and were randomly allocated to either an untreated control (UTC) or an insecticide-treated (TRT) herd. Horn fly populations were monitored throughout each yearly replication and blood serum progesterone levels were used to estimate postpartum interval lengths and days to pregnancy. Initial body weights of cows were collected in May with final body weights and calf weaning weights acquired in October of each year. Monthly horn fly control ranged from 85.55 to 99.57% throughout the 4 yr. Cows within UTC herds maintained on average 530.10 ± 94.74 more (P = 0.0015) flies per animal than TRT. However, no differences were detected between treatment groups for any of the reproductive parameters evaluated (P > 0.05). Despite a lack of difference in the reproductive parameters measured, TRT cows gained more (P = 0.0492) weight throughout the fly seasons when compared to UTC cattle. Furthermore, calves paired with insecticide-treated cows tended (P = 0.0680) to wean 16.28 ± 8.04 kg heavier than calves paired with cows exposed to naturally occurring horn fly populations.

Postpartum oestrous cycling resumption of yak cows following different calf weaning strategies under range conditions.

Early weaning can improve body condition and reproductive performance of cows. The objectives of this study were to examine and compare oestrous cycling resumption, behaviour and blood parameters of yak cows following four different strategies of calf weaning. Twenty-six yak cows (4-8years) and their calves (94.3±2.4days) were studied in which calves were: weaned naturally with free access to their mothers (NW; n=13); weaned abruptly and separated permanently from their mothers (PW; n=5); separated temporarily from their mothers for 15days (TW; n=5); and fitted with nose plates for 15days, but allowed free access to their mothers (NP; n=3). Yak cows with sucking calves (NW) spent more time grazing in the cold season (from d 39 to 84). Based on serum progesterone concentrations, none of nine NW yak cows resumed oestrous cycling during the study, while seven of nine yak cows with weaned calves resumed cycling (3/3 for PW; 2/3 for TW; and 2/3 for NP yaks). We concluded that early weaning improved postpartum reproductive performance of yak cows on the Qinghai-Tibetan plateau and that abrupt and permanent weaning was an appropriate strategy.