Enhancing pregnancy rates in Bali cattle (Bos javanicus) through prostaglandin F₂α–based estrus synchronization

This study evaluated the effectiveness of estrus synchronization using prostaglandin F2α (PGF2α) in Bali cattle and assessed the pregnancy outcomes following the initial treatment and subsequent resynchronization. Ten Bali cattle received two PGF2α injections, administered 11 days apart, following standard recommendations. Animals exhibiting estrus were artificially inseminated, and pregnancy diagnosis was performed 30–45 days post-insemination using ultrasonography. Cattle that failed to conceive during the first cycle underwent a resynchronization protocol two weeks later. The synchronization protocol produced a 100% estrus response, with an initial pregnancy rate of 40% (4 cattle). Resynchronization of the six non-pregnant cattle yielded two additional pregnancies (33.3%), resulting in an overall pregnancy rate of 60%. These findings demonstrate that PGF2α is effective in regulating the estrus cycle and enhancing the reproductive efficiency of Bali cattle, particularly when integrated with a resynchronization strategy.