THE GROWTH PATTERNS OF CARCASS TISSUES WITHIN WHOLESALE CUTS IN FATTENING STEER

Abstract

An investigation was conducted on beef carcasses, aimed at identifying the growth patterns of wholesale cuts and their tissues in steer during fattening phase. This study involved 69 grass-fed steers with a live-weight range of 300 to 600 kg. They had entered, or were progressing along, their fat deposition phase. An allometric model (Huxley, 1932) was used to study the growth patterns of carcass tissues within wholesale cuts. In general, The growths of muscle and fat within wholesale cuts followed similar patterns. Some differences in growth patterns between muscle and fat were identified on the dorsal region. The growth impetus for fat moved from the thoracic backwards to the lumbar region which was the reverse of the growth impetus for muscle. Differential growth patterns occurred between intermuscular (IM) fat and subcutaneous (SC) fat. With IM fat, its growth movement was similar to that of total fat where there was a concentration of growth in the lumbar area and thin flank as side weight increased. With SC fat, there were growth movements from the ventral region to the dorsal region of the carcass. Bone growth within wholesale cuts showed a less clear pattern. Keywords : Fattening Phase, Steer, Growth Pattern, Carcass Tissue, Wholesale Cut.