Comparative advantages of cervical insemination over natural mating on production of crossbred lambs for export market.

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 (P0.05). 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.