Research Article
Salima Bacha, Baghdad Khiat
Abstract
The current study was designed to evaluate the effect of different doses of pregnant mare serum gonadotropin (PMSG) on reproductive performance of Rembi ewe during seasonal anoestrus. A total of 120 sheep and 12 rams of Rembi ewe lamb were used in this experiment. Vaginal sponges containing 40 mg of fluorogestone acetate were inserted into the vagina of the ewes. The sponges were withdrawn on day 7 and 300 IU of PMSG (group 1, n=30, 500 IU of PMSG (group 2, n=30) and 700 IU of PMSG (group 3, n=30) were injected intramuscularly. The rates of fertility in groups 2, 3, 4 and the control group were found as 86,2%, 79,3%, 72,4%, and 44,8%, respectively. Fecundity rates were 1.14%, 1.20%, 1.03% and 0.48% in groups 2, 3, 4 and the control group, respectively. The rates of prolificacy in groups 2, 3, and 4 which received different doses of PMSG and the control group were found as 1.08%, 1.52 %, 1.43%, and 1.08%, respectively. Lambing rates were obtained as 67.5%, 77.5%, 77.5% and 58.8% in groups1, 2, 3 and in control group, respectively. The effect of the hormonal treatments on the birth weight of lambs averaging 1.90 ± 0.16, 2.60 ± 0.11 and 3.25 ± 0.19 kg respectively. The application of 500 IU PMSG was rather more effective than injections of 300 IU and 700 IU in Rembi ewes being outside the breeding season.