A systematic review and meta-analysis of ovarian lavage sperm artificial insemination and its impact on reproductive performance in external fertilization of fish

This study was conducted to determine social-economic characteristics of farmers and inseminators, to determine the performance of beef cattle reproduction in the implementation artificial insemination (AI) program, institution of AI and to determine of income from beef cattle farmers was used AI and also factors influencing them. Respondents consist of 60 farmers and 33 Inseminators were taken by using purposive sampling. This research used primary data and secondary data were taken by using survey method. Observed variables were social-economic characteristic of respondent, performance of beef cattle reproduction (calf weaning, postpartum mating, service per conception (S/C) and calving interval (C.I)), institute of AI and income of beef cattle farmers. This research use analysis which consist of t- test to compare performance of beef cattle reproduction between AI program with natural breeding and regression analysis to know the factors affecting of income level. The result of research showed that calf weaning and C.I of AI at t- test have significant difference compare to natural breeding, post partum mating and S/C on AI and natural breeding shows insignificant difference. Analysis result of regression showed F equal to 9.007 significant (P< 0.01) and coefficient of determinant R2 equal to this 0.505 that mean 50.50% dependent variable can be explained by free variable, while the rest 49.50% explained by other variables outside. The factors that significantly affected the option of income are farm experience (P<0.01), cost of breeding (P<0.10), and dummy variable (P<0.01). The farm experience and dummy variable had positive effect while cost of breeding had negative effect. Keyword : Insemination, Beef cattle, Performance of reproduction.

This research aims to determine Bali cows’ reproductive management and performances, kept by smallholder farmers with intensive and semi-intensive production systems in South Konawe Regency. A total of 55 farmers and 110 Bali cows was interviewed and observed. The data was captured consists of farmers’ characteristics, reproductive management, and reproductive performances. An independent sample t-test analyzed the data. The farmers with intensive and semi-intensive production systems could detect the estrus well (69.57 and 59.09%) and mated by artificial insemination (AI) (70.83 and 86.11%). There was a significant difference (P <0.05) related to the first estrus age (1.98±0.82 vs. 1.92±0.18 years), the first mating age (2.84±0.23 vs. 2.77±0.34 years), service per conception with natural mating and AI (1.00±0.00 vs. 1.20±0.42 and 1.70±0.76 vs. 1.44±0.57 times). There were no significant differences in the first calving age, gestation length, postpartum estrus, postpartum mating, weaning age, calving interval, and cow reproduction index. The pre-weaning mortality and calf crops were 6.25 and 9.68%; 76.79 and 71,70%. To conclude our findings, the farmers in South Konawe Regency carry out reproductive management well. Bali cows’ reproductive performance with an intensive system is better than the semi-intensive system based on the calf crop.

AIM: To describe the effect of treatment of cows not detected in oestrus (NDO) with progesterone (P4) and oestradiol benzoate (ODB) in one lactation, on the reproductive and productive performance in the subsequent lactation. METHODS: Cows (n=770 from nine herds) which were NDO 10 days before the planned start of the seasonal breeding programme (PSM) were blocked by herd, age (2 or >2 years old) and ovarian status (i.e. with or without a palpable corpus luteum; CL), and treated either with an intravaginal progesteronereleasing device and ODB and resynchrony, or were left as untreated controls. In the following lactation, data were collected on the occurrence of endometritis, NDO, breeding dates, pregnancy test results and milk production. The effect of treatment and ovarian status in the previous lactation on the incidence of disease, and the proportions submitted for service, conceived and pregnant in the subsequent lactation were analysed. Calving dates and intervals from start of breeding to first insemination and conception were analysed using Kaplan Meier survival analysis. Additional multivariate analyses were undertaken to include known confounders such as age, breed, herd, calving date and milk production, as well as the cyclic status (i.e. previously cycling, NDO, or ‘late-calving’) in the previous lactation, to examine the potential ‘carryover’ effects of previous status on the reproductive performance in the subsequent lactation. RESULTS: Treatment of NDO cows resulted in an earlier calving date (Julian calving date 214, 95% CI=207–221, vs 224, 95% CI=220–228; p=0.005), more female calves reared (31.4% vs 23.3%; p=0.01), and reduced risk of being NDO (33.9% vs 46.1%; p=0.002) in the subsequent lactation compared with controls. There were no differences in the incidence of peripartum disease, or the proportion of cows submitted, conceived or pregnant between the Treatment and Control groups in the subsequent lactation (p>0.2). Previously CL-positive (+ve) NDO cows were less likely to produce a female calf that was reared (19.0% vs 29.9%; p=0.005), more likely to be treated as NDO (26.4% vs 18.6%; p=0.02), less likely to conceive by the end of the subsequent lactation's breeding programme (82.2% vs 87.8%; p=0.09), and took longer to conceive (41 vs 33 days from the PSM to conception) than cows that were NDO-CL-negative (-ve) in the previous lactation. There was no interaction between ovarian status and treatment for any of the outcome variables (p>0.05). Cows that were NDO or late-calving in the previous lactation were more likely to be NDO (p<0.005), treated as NDO (p<0.005), and have longer PSM Animal Health Centre, PO Box 21, Morrinsville, New Zealand. Author for correspondence. Email: smcdoug@ahc.co.nz to conception intervals (p<0.005) in the subsequent lactation than cycling herdmates, despite inclusion of factors known to confound reproductive performance in analyses. CONCLUSIONS: Treatment of NDO cows resulted in more female calves reared, earlier calving and a reduced risk of being NDO in the subsequent lactation. Status (i.e. NDO-CL+ve or NDO-CL-ve) affected some reproductive measures in the subsequent lactation, and the effect of treatment in the subsequent lactation differed between the two groups for some measures. Reproductive performance in the subsequent lactation was not improved despite the earlier calving date and longer calving to PSM intervals. Additionally, the previous season's status was still important in the subsequent season's reproductive performance, despite adjusting for known confounders of fertility. CLINICAL RELEVANCE: The economic benefits from treatment of NDO cows are likely limited to effects of an earlier calving date and potential for longer lactation and increased milk yield, increased number of calves derived from artificial insemination and from a reduced number of NDO cows in the subsequent lactation. Effects of improved reproductive performance in the subsequent lactation were not demonstrated and hence should not be included in any economic analysis of therapy of NDO cows.

Reproductive strategies for dairy heifers based on 5d-Cosynch with or without an intravaginal progesterone device and observed estrus

Reproductive management practices and performance of Canadian dairy herds using automated activity-monitoring systems

Characteristics of offspring derived from conventional and X-sorted bovine sperm

Mixing aggression intensity is associated with age at first service and floor type during gestation, with implications for sow reproductive performance

Background: The present study was conducted with the objective of assessing major factors that affect the reproductive performance and disorders of dairy cows in Rajshahi region. Methods: A cross-sectional study was conducted during the period from January 2014 to June 2015. Data on herd size, feed quality, breeding, grazing, management system, reproductive disorders, age at puberty, age at firs calving, post-partum heat period, service per conception, days open and calving interval of 500 cows were collected from farm owners by administering a questionnaire. We recorded the important diseases contacting farmers by mobile phone and visiting the farms. The effect of farm size, rearing system, feed quality and preventive measure on reproductive performance were evaluated by analysis of variance and Duncan multiple range test. Unpaired T-test was used to compare the reproductive performance according to breeding. Chi-square test was used to compare between two categories of a dichotomous outcome.. Results: The age at puberty, age at first calving, post-partum heat period, service per conception, days open and calving interval were 26.42±0.22 m, 35.48±0.22 m, 121.85±3.48 days, 1.93±0.04, 136.80±3.57 days and 401.04±3.94 days, respectively. Farm size had significant effect (P&lt;0.05) on all reproductive traits (RT) except on service per conception and days open. The best reproductive performance (RP) was found in small size farm, good quality of feed, AI breeding method and preventive measure by veterinarian. Among the disorders, anoestrus, abortion, repeat breeding, retained placenta were most prevalent followed by dystocia, mastitis, vaginal prolapse, pyometra, metritis, uterine prolapse, milk fever, and still birth. The highest prevalence of reproductive disorders (RD) was found in intensive rearing system (39.8%). The prevalence of all RDs was higher in artificially inseminated cows (59.6%) than those bred by natural service (19.0%). Conclusion: The study revealed a lower RP of dairy cows and higher prevalence of RDs. The better reproductive performance was recorded in small than large and medium farms. Good quality of feed should be offered to dairy cow for better reproductive performance. Artificial insemination should also be preferred than natural service for better reproductive performance. Measures to control reproductive diseases should be undertaken in large herds and intensive housing system.

Associations among patterns in daily body weight, body condition scoring, and reproductive performance in high-producing dairy cows

Associations Between Herd Characteristics and Reproductive Efficiency in Dairy Herds

This analysis introduces a stochastic herd simulation model and evaluates the estimated reproductive and economic performance of combinations of reproductive management programs for both heifers and lactating cows. The model simulates the growth, reproductive performance, production, and culling for individual animals and integrates individual animal outcomes to represent herd dynamics daily. The model has an extensible structure, allowing for future modification and expansion, and has been integrated into the Ruminant Farm Systems model, a holistic dairy farm simulation model. The herd simulation model was used to compare outcomes of 10 reproductive management scenarios based on common practices on US farms with combinations of estrous detection (ED) and artificial insemination (AI), synchronized estrous detection (synch-ED) and AI, timed AI (TAI, 5-d CIDR-Synch) programs for heifers; and ED, a combination of ED and TAI (ED-TAI, Presynch-Ovsynch), and TAI (Double-Ovsynch) with or without ED during the reinsemination period for lactating cows. The simulation was run for a 1,000-cow (milking and dry) herd for 7 yr, and we used the outcomes from the final year to evaluate results. The model accounted for incomes from milk, sold calves, and culled heifers and cows, as well as costs from breeding, AI, semen, pregnancy diagnosis, and calf, heifer, and cow feed. We found that the interaction between heifer and lactating dairy cow reproductive management programs influences herd economic performance primarily due to heifer rearing costs and replacement heifer supply. The greatest net return (NR) was achieved when combining heifer TAI and cow TAI without ED during the reinsemination period, whereas the lowest NR was obtained when combining heifer synch-ED with cow ED.

As global demand for sheep products increases, improving reproductive efficiency and lamb growth performance has become a priority for sheep farmers. Artificial insemination (AI) offers several advantages over natural mating, including improved genetic selection and disease control. This study contributes to understanding the impact of different mating methods and semen preservation techniques on reproductive performance and growth traits in Palestinian Assaf sheep under local breeding conditions. The research included 123 adult Assaf ewes from two farms, which were hormonally synchronized and divided into three groups for different reproductive biotechnologies. Group 1 (G1) comprised 50 ewes inseminated with frozen semen straws, while Group 2 (G2) had 37 ewes inseminated with fresh semen from genetically superior rams. Both G1 and G2 used 0.5 mL straws containing 250 million sperm, with insemination occurring 48 h post sponge removal and eCG hormone injection. Group 3 (G3) consisted of 36 ewes that underwent natural mating at a ratio of 1 ram to 6 ewes. The study revealed that insemination methods significantly affected fertility rates (45.4, 61.1, and 71.9% for G1, G2, and G3, respectively; p < 0.05). Artificial insemination notably enhanced lamb performance indicators (p < 0.05), although it did not significantly influence prolific lambing (p > 0.05). Prolific lambing significantly impacted birth weight, weaning weight, and average daily gain at 60 days across all groups (p < 0.05), but not the average daily gain or final weight at 180 days (p > 0.05). The management system significantly affected birth and weaning weights at 60 days (p < 0.05), but not the final weight at 180 days or prolific lambing (p > 0.05). Lamb sex significantly influenced average daily gains at 60 and 180 days, as well as final weight at 180 days (p < 0.05). The findings suggest that, while artificial insemination with semen from elite rams may reduce fertility rates, it significantly improves lamb performance rates. In conclusion, our study demonstrates that, while natural mating offers higher fertility rates, AI with fresh semen can be a valuable tool for improving lamb growth performance in Palestinian Assaf sheep. These findings provide valuable insights for sheep farmers in the region to optimize reproductive strategies and enhance lamb production.

Does feeding extruded linseed to dairy cows improve reproductive performance in dairy herds? An observational study

The objective of this retrospective observational study was to evaluate associations between predictor variables and reproductive performance outcomes in seasonal-calving, pasture-based dairy cows. Individual cow data were available from 5,845 lactations across 21 herds in 2022 and 2023. Cow data records included genomic proofs, milk production, calving and reproduction events, as well as health and estrus alerts from automated activity monitoring systems. The breeding start date (BSD) was defined for each herd, and reproductive outcomes included the proportion of cows submitted for artificial insemination (AI) within 21 d of BSD (SR21), first service pregnancy per AI (P/AI1), BSD to conception interval (BSD-CI), and the proportion of cows pregnant in 42 d (P42) and 84 d (P84). Several cow-level factors were evaluated in univariable and multivariable models: parity (1, 2, 3, ≥4), number of automated estrus alerts (AEA) before BSD (0, 1, ≥2), fertility subindex (FI; high [>€93.58], medium [€93.58-68.14], low [<€68.14]), severity of automated health alerts (AHA) within 50 DIM (none, mild [index >65], severe [index ≤65]), calving assistance (unassisted vs. assisted or twins), milk yield at 80 DIM, DIM at BSD, and semen type (sex-sorted vs. conventional). Several factors were associated with reproductive performance. Cows with ≥2 AEA before BSD had greater SR21 (94% vs. 85%), greater P/AI1 (52% vs. 42%), and shorter BSD-CI (23 vs. 27 d) than cows with no AEA. High- and medium-FI cows had greater reproductive performance compared with low-FI cows (P/AI1: 49%, 48% vs. 44%; BSD-CI: 23, 23 vs. 25 d, respectively). Cows with no or mild AHA in early lactation had greater P/AI1 (49%) and shorter BSD-CI (23 d) than those with severe AHA (44% and 25 d). Primiparous cows had greater reproductive performance (P/AI1: 50%; BSD-CI: 23 d) than multiparous cows (≥4 lactations: 45%, 24 d). The DIM at BSD was significant across all fertility outcomes, whereas milk yield was not. To identify subgroups with large differences in reproductive performance potential, variables associated with reduced reproductive performance were assigned risk score values for poor reproductive performance proportional to β-coefficients from the multivariable model. Cows were subsequently stratified by risk score into low (score ≤2, 25% of data), medium (3-8, 54% of data), and high risk (≥9; 21% of data). High-risk cows were more likely to be multiparous, have no AEA, fewer DIM at BSD, and have early-lactation health alerts. High-risk cows had lower SR21 (74%), P/AI1 (37%), P42 (51%), and P84 (71%) and reduced hazard of pregnancy (0.50, 95% CI: 0.46 to 0.55) than low-risk cows (SR21: 96%, P/AI1: 61%; P42: 80%, P84: 90%). Combining multiple predictors enabled identification of subgroups with more meaningful fertility differences than any single factor alone. These findings support the future development of targeted reproductive management strategies and decision-support tools for pasture-based, seasonal-calving systems. Further work is needed to evaluate the utility of this grouping approach for real-time on-farm decision making.

Feed costs represent ~50% of beef production costs making selection for improved efficiency without affecting female reproduction critical to the cow/calf sector. Objectives were to determine the relationship between post-weaning feed efficiency and female fertility in commercial (n = 19) and half-blood Lowline-influenced Angus heifers (n = 20). Yearling heifers were delivered to the CSU, Chico Farm cattle feeding unit 45-d post weaning and randomly assigned to one of three 7 x 18 m pens, equipped with GrowSafe feeding units. Heifers were given ad libitum access to water and a forage-based diet targeting 0.68 kg gain/d (TDN: 54%, CP: 14%, and NDF: 39.7%, on a DM basis) for 72-d. Feed efficiency measures included dry matter intake (DMI), feed conversion ratio (FCR) and residual feed intake (RFI). Heifer RFI was calculated as the difference between predicted DMI and actual DMI during the trial. Feed efficiency groups were identified as: 1) low RFI (0.5 SD above the RFI mean), 2) marginal RFI (+/- 0.5 SD about the RFI mean), and 3) high RFI (0.5 SD above the RFI mean). Serial weights were taken every 14-d to calculate average daily gain (ADG) and metabolic midweight (MMWT). Heifers were synchronized using a 14-d CIDR-PG protocol. Heifers received PG injection 16-d post-CIDR removal and were equipped with an estrous detection patch. Estrous behavior was observed morning and evening for 90-h. Heifers were artificially inseminated (AI) 12-h post-standing estrus and injected with 2 mL GnRH. Pregnancy determination via rectal palpation occurred 6-mos after initial AI. Reproductive measures included: first service conception (FSC), pregnancy rate (PR), and response to estrous synchronization (RES). Reproductive traits were analyzed using the GLM procedures of SPSS with a binary logistic response. Breed type and feed efficiency group were independent variables. Relationships among reproductive measures and performance were analyzed using logistic regression of SPSS, fitting the independent variables of ADG, DMI, and RFI. Traits FSC, PR, and RES did not differ among breed types or feed efficiency groups (P &amp;gt; 0.05) and DMI, ADG and RFI were not predictors of FSC, PR, nor RES (P &amp;gt; 0.05). Cumulatively, results indicate there is no relationship between feed efficiency and reproductive performance. Producers can select for low RFI to decrease feed costs without compromising reproductive performance.