Thirteen Katahdin (KT) sired male lambs were weaned at 60 days, placed in individual pens and fed on a mixture of commercial feed pellets (14% CP) and sugar cane bagasse. Each ram was randomly assigned to one of 4 groups. Animals in each group were reared to mean live-weights (± 1 kg) of 35 kg (Group 1), 40 kg (Group 2), 45 kg (Group 3) and 50 kg (Group 4). Average daily gain (ADG), feed conversion ratio (FCR), total feed cost per unit weight gained as well as dressing percentage was not significantly different (P>0.05) among groups. Based on these indices as well as the significantly (P<0.01) longer post weaning period required to attain the respective live-weights associated with the significantly greater (P< 0.01) deposition of belly fat and the relatively low increases in income over feed costs, it is recommended that KT crossbred lambs be slaughtered upon attaining a live-weight of 35 kg.