Beef carcasses, weighing between 190 and 240 kg, were selected to represent the South African commercial market and the
national carcass classification system. This system classifies carcasses based on age and carcass fatness, regardless of genotype (Agricultural Product Standards Act, 1990 (Act No. 119 of 1990)). The three age groups selected were from class A (younger than 18 months and no permanent incisors have erupted), class AB (18–24 months, with one to two permanent incisors)