مرکز منطقه ای اطلاع رساني علوم و فناوري - Effect of recombinant follicle stimulating hormone (rFSH) on some fertility parameters in Awassi ewes synchronized with PGF2α in the breeding season

Abstract :

The present study was aimed at the investigation of the effects of Recombinant Follicle Stimulating Hormone (rFSH) on fertility in Awassi ewes synchronized with PGF2α in the breeding season. The fifty thoroughbred Awassi ewes used in the study were injected twice with 0.150 mg of Tiaprost (PGF2α, Iliren®) at a 10-day interval. Following the second PGF2α injection, the ewes were randomly distributed into two equal groups. The ewes included in the first group were not subjected to any additional injection and were referred to as the PGF2α group (Group 1, n=25). The animals included in the second group (Group 2, n=25) were administered 10 IU Follitropin (rFSH, Puregon®), diluted 1:10 with physiological saline, 24 hours before the second PGF2α injection. Ewes were tested for estrus by a fertile teasing ram three times a day (06.00, 14.00 and 20.00 h), for one hour each time. Ewes exhibiting estrus were mated naturally. Pregnancy was determined by transrectal ultrasonography on 40. d after mating. Estrus was observed at a rate of 88.0 % in Group 1 and 92.0 % in Group 2. The rate of pregnancy was 100 % in the first group and 95.6% in the second group. The rate of lambing was 100 % and 95.5 % in Groups 1 and 2, respectively. Furthermore, twin pregnancy rates were 4.5 % in the first group and 57.1% in the second group. While differences between the groups were determined to be significant (p 0.001), no significant difference was detected for pregnancy, estrus or lambing rates. In conclusion, it was determined that the administration of rFSH to Awassi ewes in the breeding season, 24 hours before the second PGF2α injection, led to an increase in twin pregnancy rates. Thereby, this protocol can be used as an alternative synchronization method to increase fertility. It has been concluded that further studies are needed to determine the effect of different doses of rFSH on fertility in ewes.