Investigation of Possibility of Increasing Lamb Production with Flushing plus Ram Effect or the Administration of Various Pregnant Mare Serum Gonadotropin Doses in Akkaraman Ewes

The effect of ram effect plus flushing or different doses of pregnant mare serum gonadotropin (PMSG) on lamb production in Akkaraman ewes was investigated. For this aim, 124 Akkaraman ewes were randomly divided into five group; The groups were PMSG300 (n=25), PMSG500 (n=24), PMSG700 (n=25), Flushing plus Ram effect (n=25) and Control (n=25) groups. The oestruses in PMSG groups were synchronised using vaginal sponge (for 12 d) containing 20 mg fluorogestone acetate and ewes were im injected 75 μ cloprostenol and 300, 500 and 700 IU PMSG in PMSG300, PMSG500, and PMSG700 groups, respectively, 24 h before sponge removal. Oestrus was checked for 5 d following sponge removal. After four weeks flushing, oestrus was checked for 4 wk in Flushing plus Ram effect group. Control ewes had no extra administration and, were checked for oestrus during August and September. Oestrus was checked for 30 min twice a day with teaser rams in all groups and ewes in oestrus were hand-mated. While pregnancy and survival rates were similar, birth rate in PMSG700 group and fecundity rate in Flushing plus Ram effect and Control groups were lower than that in PMSG500 group (P 0.05). As a result, it is concluded that 500 IU PMSG injection 24 h before sponge removal can synchronise oestrus and increase fecundity rate in Akkaraman ewes synchronised with intravaginal progesterone plus prostaglandin2alpha injection.