Quantitative carcass traits of bovines and buffalo, slaughtered at different stages of maturity

The study was designed to evaluate the effect of genetic group and slaughter weight on carcass length, back fat thickness, loin eye area, and carcass physical composition, as well as to estimate the relationships among these traits. Sixty intact males, including 16 Nellore (NE), 16 F-1 Holstein-Nellore (HN), 14 1/4 Fleckvieh-5/16 Angus-7/16 Nellore (BM), and 14 Mediterranean crossbred buffalo, were used. Animals from each genetic group were divided into four groups (categories), in such way that each animal had a corresponding one in the other three groups based on initial weight and body condition. One group was randomly assigned to immediate slaughter (AB), two groups were full-fed a ration containing 50% concentrate on a dry matter basis (AL-I and AL-2), and one group received the same ration in restricted amounts supplemented with 15% of protein and energy over maintenance (AR). The animals in AL-I were slaughtered when they reached slaughter weights of 450 kg for NE and BUF and 500 kg for BM and HN, and in AL-2 at weights of 500 kg for NE and BUF and 550 kg for BM and HN (weights corresponding to 100 and 110% of the mature weights of cows in the respective groups). Each AR animal was slaughtered when the corresponding AL-1 animal reached the slaughter weight. There were no differences among genetic groups in regard to loin eye area, expressed as percentage of empty body weight (EBW). Buffaloes had higher back fat thickness, higher proportion of adipose tissue, and a lower proportion of muscle in the carcass than bovines. AL-2 animals had a lower carcass length in relation to weight than the other groups indicating a more compact carcass. NE and BM animals had higher muscle:bone ratios than buffaloes, while HN animals did not differ from each other. Loin eye area was not a reliable indicator of muscularity.