Authors : Krittiya Lertchunhakiat, Chainarong Navanukraw, Jiratti Thammasiri, Winai Jaikan, Apiradee Swannakorn, Tossapol Moonmanee and Dale A. Redmer
Abstract: The efficiency of protocols based on synthetic progesterone (Medoxy Progesterone Acetate; MAP) and gonadotropins (PMSG/FSH) for estrus synchronization was evaluated in Thai-native goats. Nulliparous goats (n = 36) were randomly assigned to 3 treatments. Treatment 1 (14 days MAP and PMSG); goats were synchronized using 60 mg MAP for 14 days combined with 300 IU PMSG administration 24 h before MAP removal. Treatment 2 (7 days MAP and PMSG); goats received MAP for 7 days combined with 300 IU PMSG administration 24 h before MAP removal and 5 mg PGF2α administration at MAP removal. Treatment 3 (14 days MAP and FSH), goats received MAP for 14 days combined with 3 days of FSH injections in decreasing doses (24 mg total) beginning on day 12 of MAP treatment. Percentage of estrus was 100% detected in goats receiving 14 days MAP and PMSG or 7 days MAP and PMSG whereas 83.3% was observed in goats receiving 14 days MAP and FSH (p>0.05). Time from MAP removal to onset of estrus was significantly advanced (p<0.05) in goats receiving 14 days MAP and FSH (27.8±2.3 h) when compared to goats receiving 7 days MAP and PMSG (42.0±3.5 h). Duration of estrus was longer in goats receiving 14 days MAP and PMSG (34.0±3.3 h) than those receiving 7 days MAP and PMSG (24.0±2.1 h; p<0.05). Results indicate that estrus and ovulatory response of Thai-native goats are not different among protocols, however the use of 14 days MAP and FSH led to shorter interval to onset of estrus than the use of 7 or 14 days MAP and PMSG.
Krittiya Lertchunhakiat, Chainarong Navanukraw, Jiratti Thammasiri, Winai Jaikan, Apiradee Swannakorn, Tossapol Moonmanee and Dale A. Redmer, 2012. Evaluation of Protocols Based on Synthetic Progesterone and Gonadotropin on Estrus and Ovulatory Response in Thai-Native Goats. Journal of Animal and Veterinary Advances, 11: 3385-3389.