OVSYNCH-BASED SYNCHRONIZATION PROTOCOLS ON FIRST-SERVICE PREGNANCY RATES IN PRIMIPAROUS SIMMENTAL COWS
DOI:
https://doi.org/10.26873/SVR-2344-2026Keywords:
dairy cows, estrus response, Ovsynch, PGF₂α, pregnancy rate, synchronization protocolsAbstract
This study compared the effects of three Ovsynch-based synchronization protocols on first-service pregnancy rates in primiparous Simmental cows under field conditions. Materials and Methods: A total of 69 primiparous Simmental cows meeting the predefined inclusion criteria were randomly assigned to three groups (n = 23/group): PGF₂α pre-treatment followed by Ovsynch (Group 1), classical Ovsynch (Group 2), and Ovsynch with an additional PGF₂α administration on day 8 (Group 3). All animals underwent timed artificial insemination, and pregnancy diagnosis was performed by transrectal ultrasonography 30 days post-insemination. Results: Pregnancy rates were 56.5%, 43.5%, and 34.8% for Groups 1, 2, and 3, respectively, with no statistically significant differences among groups (p > 0.05). Estrus response following the first hormonal administration was observed in 21.7%, 17.4%, and 4.3% of animals, respectively, also without significant differences (p > 0.05). Conclusion: No statistically significant differences were observed among the synchronization protocols with respect to pregnancy rates or estrus response (p > 0.05). The results should be interpreted in light of the pilot nature of the study.
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