Marker-assisted introgression of fecundity mutation into Bar-barine sheep breed under low input production system

Abstract

The interest for gene fecundity introgression becomes an interesting method to improve sheep litter size in developing countries. In Tunisia, the Barbarine sheep is low prolific breed. A new mutation (FecXBar) in (BMP15) gene causing increased prolificacy in heterozygous and sterility in homozygous ewes has been recently discovered in Barbarine prolific line (W), created through a prolificacy-based selection program. The aims of this study were to screen and disseminate the FecXBar mutation into non-carrier conventional flocks using artificial insemination (AI) technique and based on a three-tier breeding program. The genotyping was carried out to screen the prolific mutation in the parents and their offspring F1. The AI of 334 conventional ewes using four prolific carrier rams yielded 143 lambs of which 53.15% are females. The genotyping of FecXBar in F1 animals showed that the mutation segregated in 35% of the total offspring animals and 65.8% from produced females. At puberty age, these females will be mated with conventional rams to produce improved prolific males. The scale-out of the suggested breeding program presents a starting point to produce carriers’ males in order to disseminate the fecundity mutation into commercial flocks.