Abstract

A study was conducted at Debre Birhan agricultural research center to evaluate the success of artificial insemination (AI) following oestrous synchronization in Washera ewes. A total of 32 ewes were selected from this center. All experimental animals were synchronized using single injection of 1 ml Enzaprost® intramuscularly at unknown stage of estrous cycle. Then ewes were divided into Dorper and Awassi fresh semen cervical insemination. Fixed time cervical insemination was performed in estrous ewes 48–51 hrs following 1 ml Enzaprost® injection with 0.25 ml fresh diluted Dorper and Awassi semen. Out of 32 ewes synchronized, 22 (68.8) of ewes exhibited overt sign of oestrous within 48 hrs of hormone administration. Ewe’s body condition score (BSC) wasn’t found to be a significant factor determining oestrous response to hormone treatment. The overall pregnancy, lambing and fecundity rates for cervical insemination and natural mating were 63.64, 77.27, 121.43 and 57.46, 61.57, 107.14, respectively. There was no significant difference in pregnancy, lambing and fecundity rates among ewes mated with fresh semen cervical insemination and controlled ram mating (P<0.05). The pregnancy, lambing, and fecundity rates for Awassi and Dorper semen were 58.3, 75.0, 128.57 and 70.0, 80.0, 114.29, respectively. No significance differences were observed in pregnancy, lambing and fecundity rates among the genotypes (P<0.05). The current work strongly indicated that artificial insemination following oestrous synchronization has a tremendous impact on terminal crossing, that allows us to import fewer exotic genotypes and producing large number of crossbreed lambs from imported breed with in few years. © 2020. All rights reserved.