Abstract

For the past 5 years ram lam bs in an experimental Suffolk flock have been selected on an index o f live weight and ultrasonic fat and m uscle depths at 150 days of age. In 1989 lambs from the selection line showed significant responses o f about 7.8 and 8.7 per cent in index score for males and females respectively, com pared to lam bs from a control line. Preliminary results also show responses of about + 7.6 g lean and -10.2 g la t/k g carcass weight in the extensively-reared crossbred progeny of high index versus low index sires.
 

G. Simm, W. S Dingwall, S. V Murphy, J. Fitzsimons

Proceedings of the World Congress on Genetics Applied to Livestock Production, Volume XV. Beef cattle, sheep and pig genetics and breeding, fibre, fur and meat quality., , 100–103, 1990