Abstract
This study was conducted at the animal farm of the department of Animal Science, College of Agriculture, University of Tikrit, during the period from May 5, 2013 till January 1, 2014. The experiment included 48 ewes of Awassi breed with average body weight of 46.19±1.05 kg. Synchronization of estrus was done by vaginal sponges (Progestagen 20mg) for 12 days before mating. The animals were divided into four groups, injected with (GnRH 0.1mg, hCG 150IU. P4 12.5mg) hormones for the first three groups respectively, while the control one was injected with normal saline. All treatments and control were injected by eight doses, one each per seven days , started from the seventh day of mating until the Fifty-sixth day of pregnancy. No significant differences (P≥0.05) had shown in the weights of new born males and female. Still, fertility and lambing rate significant increase (P≤0.05) in groups compared with control. The result of prolificacy showed a significant increase (P≤0.05) in two treated groups hCG and P4 compared with GnRH and control. Increase of late fetal mortality in control Followed by the P4 group. It was concluded from this study that. This study concludes that treated Awassi ewes by GnRH, hCG and P4 hormones during early pregnancy had been instrumental to significant increase some characteristics of reproductive performance.
Main Subjects