Development of a new protocol for estrus induction and synchronizationin multiparous weaned sows

Abstract

Estrus induction and estrus synchronization with P.G. 600 to improve the reproductive performance of multiparous sows is a standard protocol. However, its nonavailability in India and higher cost warrants development of new protocols without compromising the reproductive performance. The present study compared the efficacy of two different protocols for estrus induction and synchronization in multiparous sows. The sows (n=80) were randomly divided into two groups. In group-I, sows (n=40) were injected with P.G. 600 (equine chorionic gonadotropin [eCG] 400 I.U. and human chorionic gonadotropin [hCG] 200 I.U.) and in group-II, P.G. 450 (eCG 300 I.U. and hCG 150 I.U.) intramuscularly. Reproductive performance parameters, including estrus induction, treatment to estrus induction interval, estrus duration, farrowing rate, live born piglets/litter, stillborn piglets, total piglets born/litter, litter size at weaning and pre-weaning mortality were analyzed between two groups. Estrus induction and farrowing rate were numerically higher in group-II but statistically nonsignificant. Treatment to estrus induction interval was 55.59 h and 55.57 h, respectively in group-I and group-II. Similarly, total litter size at birth and litter size at weaning were non-statistically higher in group-II as compared to group-I. In conclusion, the present study demonstrated that estrus induction and synchronization can be successfully achieved in multiparous sows with P.G. 450 and this will reduce the cost of hormonal treatment and optimize the reproductive efficiency in Indian condition.