Effects of FGA sponge and Ovsynch based protocols on reproductive performance of fat-tailed ewes during the breeding season [Aşi{dotless}m mevsimindeki yaǧli{dotless} kuyrukli{dotless} koyunlarda FGA ve Ovsynch temelli senkronizasyon protokollerinin üreme performansi{dotless} üzerine etkileri]

The effects of different synchronisation prototocols on the reproductive parameters of fat-tailed ewes during the breeding season were studied herein. seventy-one multiparous fat-tailed ewes were randomly divided into four treatment groups,as follows; group 1 (long-term fga): for a total of 20 ewes,20 mg fga sponges inserted intravaginally for 14 d,plus an i.m. injection of 400 iu pmsg upon the sponge withdrawal,group 2 (short-term fga): for 18 ewes,the insertion of sponges for 8 d,plus the pmsg injection on day 8 upon the sponge withdrawal,group 3 (ovsynch): for 17 ewes,an i.m. injection of 0.004 mg gnrh on day zero,followed by the injection of 125 μg pgf2α on day 7 and the second gnrh injection on day 9,and group 4 (short-term fga plus ovsynch): for 16 ewes,the fga sponge inserted along with the first gnrh injection (as day zero),pgf2α injection on day 7 upon the sponge withdrawal,and the second gnrh injection on day 9. the results showed that; time to onset of oestrus (p<0.001),duration of oestrus (p<0.05),the rates of pregnancy (p<0.01) and lambing (p≤0.001) differed between the synchronisation groups. overall,findings of onset/duration of oestrus and pregnancy/lambing rates suggest that; the standard ovsynch synchronisation programme was markedly inferior to the long- and short-term fga sponge protocols in fat-tailed ewes during the breeding season.