Aim: The aim of this study was to compare the fertility obtained with eCG and PGF2α treatment, at time of FGA impregnated sponge withdrawal or 48 h before, in ewes during anoestrous season.

Materials and Methods: Research was conducted on 80 ewes. The FGA containing sponges were maintained in the vagina for 12 days. Ewes received an intramuscular injection of 400 IU eCG and 125 mcg cloprostenol at the time of sponge withdrawal in the Group1 (n=40) and 48 hours before sponge removal in the Group 2 (n=40). Additionally, all of the ewes in the study received 5 mcg buserelin acetate intramuscularly 40 hours after the sponge withdrawal.

Results: Intervals from sponge removal and the onset of estrus were 35.08±1.75 and 32.12±1.41 hours in Group 1 and Group 2, respectively. The estrus, pregnancy and conception rates were 68.4%, 55.2%, 80.7% and 89.4%, 76%, 85.2% in the Groups 1 and 2, respectively. The twinning rate and litter sizes were 50% and 31%, 150% and 131% in the Groups 1 and 2, respectively. Estrus rate of Group 2 was statistically higher than Group 1 (P<0.05). No statistical difference was found in other fertility parameters between the groups (P>0.05).

Conclusion: It may be stated that the injections of eCG and cloprostenol at the time of sponge removal is supposed an advantage for less requirement of visit to the farms.