Estimates of combining abilities and maternal influence in crosses between Merino, Ossimi and Barki sheep

Abstract

SUMMARYA total of 523 lambing records were used to study general combining ability (g.c.a.), maternal ability and specific combining ability (s.c.a.) for three breeds of sheep, the native Ossimi and Barki and the Fleisch Merino. All possible combinations along with the pure breeds were represented. Traits studied were: birth, weaning (4-months) and yearling body weights; lamb survival at weaning; fleece weight and staple length.Ossimi showed the highest g.c.a. estimates for all traits except birth weight and fleece weight where Merino was the best, and survival where Barki was the best. Barki showed the worst g.c.a. in all traits except survival and staple length for which Merino had the lowest estimates.Barki exhibited the best maternal ability in weaning and yearling body weights and lamb survival, while Ossimi was best in the other traits. Merino was consistently worst in maternal ability. The two native breeds interacted more favourably with each other than with Merino in lamb production traits. Among the purebred lambs, the Ossimis performed the best in all traits except fleece weight where they were excelled by the Merinos. It was concluded that for marketing weights (i.e. weaning and yearling) and especially when viewed with respect to survival, the Ossimi × Barki cross offers the highest production; while for fleece weight the Merino × Ossimi is the best.