Effects of progestagen and pmsg on estrous synchronization and fertility in Kivircik ewes during natural breeding season

Abstract

An experiment was conducted using indigenous Kivircik ewes to evaluate the effect of intravaginal progestagen sponges, containing 30 mg of fluorogestone acetate (FGA), followed by administration of pregnant mare serum gonadotrophin (PMSG) on inducing synchronized oestrus in the season and fertility. Three times of PMSG administration relative to sponge withdrawal (24 h before (n = 30), at (n = 29) or 24 h after (n = 29)) and two routes of PMSG administration (intramuscular (n = 46) and subcutaneous (n = 42) were compared for estrous response, number of multiple births and fecundity rates. There were no significant differences in terms of estrous response, due to differences in the time and route of PMSG administration. Lambing percentage, proportion of multiple births and fecundity were 75.6, 51.6 and 114.6%, respectively. The administration had a significant effect on lambing (p<0.05). multiple birth and fecundity rates (p<0.01). The subcutaneous administration of PMSG resulted in a significantly higher lambing rate (p<0.05) and fecundity rate (p<0.01), compared to the intramuscular injection of the PMSG.