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Objective: To evaluate the ret of ovarian cyclicity with four hormone based protocols during non-breeding season in infertile Corriedale sheep. Methods: The ret to ovarian cyclicity was considered in terms of percent estrous response rate (ERR). The time of exhibition of estrus after either sponge removal or last PGF2-αinjection, was considered as time to onset of estrus. Infertile Corriedale ewes were randomly selected and distributed into four groups corresponding to four hormonal protocols such as PsE (intravaginal progesterone sponges for 12 days and eCG (equine chorionic gonadotropin) at the time of sponge removal;n=6), GP (GnRH on day 0 and PGF2-αon day 5; n=7), GPG (GnRH on day 0, PGF2-αon day 5 and second injection of GnRH on day 7; n=7) and PsPG (Intravaginal progesterone sponges for 12 days, PGF2-αand gonadotropin releasing hormone (GnRH) respectively, at 24 hour before and after sponge removal; n=8). Results: PsPG protocol produced significantly (P<0.05) higher ERR (87.5%) in ewes as compared to GPG (28.57%) but non-significantly (P>0.05) higher than GP (85.71%) and PsE (66%). Estrus was compact and more synchronized in PsPG group because 75 % of ewes exhibited estrus during the first 48 hours. The collective incidence of estrus (78.94 %) was also maximum during the first 48 hours. Conclusion: PsPG estrus induction strategy has a potential to replace eCG based protocols for reting of ovarian cyclicity in infertile Corriedale sheep.