Repeat Breeding Syndrome and its Management Protocols in a Dairy Farm

Abstract

Aims: The study involved sixty dairy cows aimed at identifying causes of repeat breeding syndrome, assessing the responses to three hormonal protocols, and evaluating conception rates following natural and artificial insemination.  Place and Duration of Study: The study was conducted at Dairy Castle Farm in Birol, Dinajpur (25°31'–25°46' N; 88°26'–88°38' E), from June 2018 to May 2019. The area has a humid subtropical climate (20–35°C, 70% humidity). Methodology: Three protocols—Select synch, Ovsynch, and PGF2α plus PGF2α—were administered based on rectal palpation findings. Estrus was detected via visual signs and vaginal electrical resistance thrice daily. Cows in estrus were inseminated by Artificial Insemination and natural service. Pregnancy was confirmed by non-return to estrus within 21 days and rectal palpation at 90 days post-insemination. Results: Approximately 54.72% of cows were diagnosed with cystic ovarian degeneration. Estrous response rates were high across all protocols: 100% for Select synch and Ovsynch, and 89.47% for PGF2α plus PGF2α. The mean onset of estrus was similar among groups: 49 ± 3.41 hours for Select synch, 48.6 ± 2.98 hours for Ovsynch, and 44.26 ± 15.8 hours for PGF2α plus PGF2α, with no significant differences observed. Duration of estrus also showed no significant differences: 40.1 ± 3.85 hours for Select synch, 47.1 ± 5.61 hours for Ovsynch, and 37.5 ± 13.44 hours for PGF2α plus PGF2α. The conception rates following induction of estrus by Select synch (GnRH+PGF2α) protocol, Ovsynch (GnRH+PGF2α+GnRH) and PGF2α plus PGF2α protocol in dairy cows served naturally used in this experiment were 100%. It can be concluded that hormonal treatments may effectively use for improving conception rates in repeat breeder dairy cows. Conclusion: Hormonal protocols effectively synchronized estrus in Repeat Breeding Syndrome (RBS) cows. To improve RBS management: Ensure strict semen quality control during storage/transport, train AI technicians in proper insemination techniques and timing and prioritize natural service where AI infrastructure is inadequate.