Studies on Estrus Induction in Ewes during Non-Breeding Season

Abstract

The present study was aimed to study estrus induction in 30 randomly selected ewes during a non-breeding season, at government Sheep Breeding Farm Panthal, Katra, Reasi, Jaamu and Kashmir. Ewes selected were divided into 5 groups (GI, GII, GIII, GIV & GV), each group consisting of 6 ewes (n = 6), which were treated with different hormonal protocols as (GI = 1/3 Norgestomet + 200 IU PMSG, GII = 1/3 Norgestomet + Ram effect, GIII = P4 sponge + PMSG 200 IU, GIV = P4 sponge + Ram effect, GV = untreated control). All the ewes (100 %) covered under hormone protocols exhibited induced estrus with intense, fair or weak estrus signs within mean onset of 25.83 ± 1.49 hrs, 44.16 ± 3.97 hrs, 29.16 ± 1.62 hrs and 54.83 ± 1.95 hrs and mean duration of estrus 28.83 ± 1.81 hrs, 36.33 ± 2.75 hrs, 25.66 ± 0.71 and 28.33 ± 2.89 hrs in GI, GII, GIII and GIV, respectively. The conception rate was similar in GI, GII, GIII (50%), while GIV showed lowest conception rate among treated groups (16.66%). The lambing rate was similar in all the groups (100%). In untreated control (GV), none of the ewes exhibited estrus.