Abstract

This investigation was designed to assess reproductive improvement in Barki ewes using different hormonal protocols. Seventy-five non-pregnant and non-lactating Barki ewes were randomly assigned into three equal groups (25 ewes each), namely G1, G2 and G3. (G1) served as control, while (G2) was treated with an intravaginal progestagen impregnated sponge for 12 days then was removed. On the ninth day, all treated ewes received an intramuscular injection of prostaglandin F2α. (G3) was also synchronized as G2, in addition to on the 10th day ewes were received an intramuscular injection of 750 IU PMSG in descending doses for three days so that the last dose was injected at the 12th day concurrently with sponges' removal. Meanwhile, on the 14th day, all ewes in G3 were received an intramuscular injection of hCG hormone (500 IU/ewe). The results showed an increase in plasma progesterone level from the first day of pregnancy and rises up to the last day before parturition. Progesterone was found to be higher in G3 (that had higher twining rate) than in G2 than in G1. Insignificant increase in estrus response was observed in groups (G2, G3) compared to G1 (100, 100 and 92%, respectively). Conception rate was significantly higher in G3 (100%) than G2 (92%) and G1 (88%). While, abortion rate was higher in G1 and surpassing G2 and G3 (9.0, 0.0 and 0.0 %, respectively). Lambing rate was significantly higher in G3 as compared to G2 and G1 groups (100, 92 and 80 %, respectively). While, weaning rate was recorded to be insignificantly higher in G2 than in G1 and G3 (100.0, 95.45 and 94.29%, respectively). It could be concluded that, hormonal manipulation using intravaginal progestagen impregnated sponge and PMSG in the presence of hCG; would be a proper way for enhancing the reproductive efficiency of Barki ewes.