EVALUATION OF ESTABLISHED BREEDS OF SHEEP IN CANADA FOR DAILY GAIN AND BODY WEIGHTS

Breed differences were assessed in the daily gain and body weights of 6356 lambs from the Federal-Provincial Canadian Record of Performance program. The breeds represented were Suffolk, Hampshire, Oxford, Lincoln, Columbia, Rambouillet, Dorset, Corriedale, Leicester, North Country Cheviot, Southdown and Finnish Landrace. Sources of variation due to the influence of year, sex, type of birth and rearing, age of dam, time of year of birth, breeder (flock) and interactions were determined together with linear regressions of daily gain and body weights at 50 and 100 d on age of lamb within breed. Significant interactions between breed and year showed that the ranking of breeds varied from year to year, probably due to sampling associated with the breeds that had fewer lambs assessed. Of the meat-type sire breeds, the Suffolk was superior in growth performance of lambs, followed by the Oxford, and Hampshire breeds. Lamb growth performance was intermediate in the Finnish Landrace Dorset, North Country Cheviot and Rambouillet breeds and lowest in the Corriedale, Leicester, Columbia, Lincoln and Southdown breeds. Key words: Sheep, breed, daily gain, body weights