PSIII-12 - The effects of PGF2 and PGF2 plus GnRH on estrous behavior and pregnancy outcomes in dairy goats

Abstract: Artificial insemination protocols depend on efficient behavioural oestrus detection and insemination time in dairy goats. Here we examined the effects of two synchronization protocols, prostaglandin F2α (PGF2α; protocol 1) and PGF2 plus gonadotropin-releasing hormone (GnRH; protocol 2) on estrus behavior, body temperature, pulse frequency, pregnancy protein B (PPB) levels, and pregnancy rates in Alpine and Saanen goats. Forty does (3.9 ± 0.28 year) were divided into two groups (20 each) with 10 Alpine and 10 Saanen females in each group. In protocol 1 goats were injected with 10 mg/goat PGF2α on day 0 and 11. In protocol 2 each goat was injected with 10 mg PGF2α on day 0, and 43 µg GnRH on day 9 and then 10 mg PGF2 α on day 11. Estrus signs were detected on 24-36 hours after the second dose of PGF2α. Body temperature and pulse frequency were recorded on days 11, 12, 13, and 14 after the second dose of PGF2α. Goats showed estrus signs were naturally bred with the same breed mature buck. Blood samples were collected on days 28, 35, and 42 post-breeding (PB) to assess PPB levels, and ultrasonography was performed on day 50 (PB) to confirm pregnancy. The percentage of female showed estrous was higher in protocol 1 than in 2 (70% vs. 60%). Irrespective to the breed, rectal and vulval temperature was higher in the protocol 2 than 1 at day 11 after PGF2 α injection, however it was the opposite at days 12, 13, and 14. However, the pulse frequency was higher (P< 0.05) in protocol 2 at all the time point. Pregnancy rates were 71.4% and 75.0% for protocols 1 and 2, respectively. Irrespective to the synchronization protocols, the pregnancy rates were significantly higher (P< 0.05) in Alpine than Saanen goats. In conclusion, both PGF2 and PGF2-GnRH protocols were effective in synchronizing estrus in Alpine and Saanen goats, with minor differences in estrus response rates and pregnancy outcomes. Breed-specific variations were observed within the protocols, indicating a potential influence of breed on the efficacy of estrous synchronization. This study contributes valuable insights to goat breeding programs and promotes more efficient and sustainable livestock management practices.