Effect of extender and artificial insemination on reproductive efficiency of ewes inseminated with frozen sperm

The aim of this study was to determine the effect of freezing medium and artificial insemination method on reproduction efficiency of Zandi ewes inseminated with frozen semen. One hundred and sixty Zandi ewes (3-4-years old, 55 kg weight) received CIDR for 12 days and at the time of CIDR removal received 400 IU of eCG and were artificially inseminated 54 h after CIDR removal. The ewes divided into two insemination groups of vaginal and trans-cervical, then, each group was inseminated with frozen sperms in extenders containing egg yolk or soybean lecithin. The results showed that the extender didn’t have any effect on sperm viability, semen lipid peroxidation and reproductive performance (P>0.05), but the artificial insemination method had a significant (P