Genetic and non-Genetic Effects on the Fleece Weight of Boujaâd and Sardi Sheep Breeds

Abstract

The analysis concerned 1937 and 2005 fleece weights of Boujaâd and Sardi sheep breeds, respectively. Data were collected during eight years from 1994 to 2001 at Deroua Experimental Station of INRA. Age at shearing, year of shearing and the animal sex had significant effects on the fleece weight of sheep of both breeds. Males under the age of 18 months showed the highest performance. Repeatability and heritability of fleece weights were estimated with the REML method applied to an animal model. Repeatability estimates for fleece weight were 0.46 and 0.57 for Boujaâd and Sardi, respectively, and heritability estimates were 0.27 and 0.40, respectively. The regression of the additive genetic value of each animal for fleece weight, estimated by the BLUP animal model, on its birth year, showed an annual genetic progress of 32 g/year for Boujaâd and 68 g/year for Sardi. It was concluded that selection would be very efficient to improve the fleece weights of Boujaâd and Sardi breeds.