Data from terminal study conducted to evaluate post-weaning growth and carcass traits of Texel, Suffolk and Columbia sired offspring were used to evaluate cultural energy analysis of lamb production in the feedlot or on pasture and in the feedlot. Study was initiated with exposing 82 whiteface ewes composed of primarily Polypay X Dorset ewes to Texel, Suffolk or Columbia rams for 35-day breeding season. The ewes were wintered outdoors on average quality alfalfa hay fed at a level to meet their NRC (1985) requirements and were not fed any concentrate during late gestation or lactation.