Performance of crossbred sheep from a synthetic Dam Line

Abstract

ABSTRACTThe performance of traditional Border Leicester × Blackface cross- breds (Greyfaces) was compared with Blackface crosses from a synthetic Dam Line developed from four breeds; Finnish Landrace (47%), East Friesian (24%), Border Leicester (17%) and Dorset Horn (12%). The Dam Line crosses were lighter (−10%), showed earlier sexual maturity, were more prolific (+12%) and weaned more lambs (+13%) than the traditional crosses but had similar litter weights and flock survival. The lambs from the Dam Line crosses grew more slowly (−5%) (comparing twins with twins and singles with singles) but their carcass composition and carcass grades were similar to those from the traditional crosses.An assessment of the relative biological efficiency for meat production of the two crossbred types indicated an advantage of about 10 to 12% in favour of the Dam Line crossbred type.