Selection differentials and breeding values of Bharat Merino Ram lambs

The performance records of 679 Bharat merino ram lambs born over a period of 13 years (1982–94) at Central Sheep and Wool Research Institute, Avikanagar, Rajasthan, India, situated in the semi-arid region of North-Western India were collected. The selection differential measured as superiority over the contemporaries for the six-month body weight ranged between −6.60 and 23.56% and that for the first six monthly greasy fleece weights ranged between 0.82 and 46.30%. The estimates of breeding value of the ram lambs used over the years for the six-month body weight and first six monthly clip showed that only 44.6 and 40.5% of the selected ram lambs had breeding values higher than the mean values of the flock for these traits. These results emphasize the need for accurate selection of ram lambs and high selection intensity for making further genetic advances in this flock for improving its productivity.