Columbia and Suffolk Terminal Sire Breed Effects

Abstract

An experiment that utilized the Suffolk breed as a standard of comparison was designed to evaluate the Columbia breed as a potential terminal sire breed. Lambs were born in 1978 to 333 Finncross ewes bred to Columbia (18) or Suffolk (10) rams. Breed of sire did not significantly affect ewe prolificacy, litter viability, number of lambs weaned per ewe lambing or litter weaning weight at 49 days of age. Litters sired by Columbia rams were lighter (P>.10) at birth than Suffolk-sired litters. Suffolk-sired lambs had higher (P>.05) birth weights, preweaning daily gains and weaning weights than lambs sired by Columbia rams. Sire breed effects on postweaning daily gain and 154-day weight were not significant but favored progeny of Suffolk rams by 4 and 2%, respectively. Columbia-sired lambs had lower leg conformation scores (P>.01), less fat depth (P>.05) and less percentage kidney fat (P>.10) than lambs sired by Suffolk rams. Progeny of Columbia rams tended to have a greater estimated percentage of trimmed retail cuts (P> .10) and less carcass weight per day of age (P>.10) than Suffolk-sired lambs, while production of retail cuts per day of age was comparable for the two breed groups. Lambs sired by Suffolk rams had higher carcass conformation scores (P>.10), maturity scores (P>.05) and flank firmness scores (P>.10) than progeny of Columbia rams. Sire breed effects on carcass quality grade were not significant. We concluded that Columbia rams produced progeny comparable in lean growth rate and carcass quality to progeny sired by Suffolk rams and that the Columbia breed may serve effectively as a terminal sire breed.