ABSTRACT
Valuation of canals of Hereford steers, reared in the inland dryland of the Mediterranean subhumid region of Chile

Julia Avendaño R.1 y Carlos Ovalle M.2
 

During three productive cycles, Hereford steers,startingfrom weaning,were reared and fattened under three fattening alternatives: (E) extensive, 420 kg/29 months of age; (S) semi-extensive, 400 kg/25 months; and (I) intensive, 380 kg/21 months. The steers grazed year round on a natural range and received different supplements, depending on the alternativa's final L.W. and age programed. Slaughter weights of E2, E3, S2, and S3 (454, 467, 457, and 432 kg, respectively) were reached before the programed ages. The programed weights in l were reached only at 21 month-old (397 and 341 kg on 1 and 12, respectively). Carcass weights and Iengths, dressing percentages (R.C.), gross (l.C.B.) and net (I.C.N.) carnosity indexes, and subcutaneous fat thicknesses were statistically different, according to cycle and fattening alternative; ranges were: 216-273 kg; 116-126 cm; 54.4-66.1%;-12.4 to 15.6; 10:1-21:1; and 0.25-0.87 cm, respectively. Eye muscle area (A. L.) and height (H. L.) were different (P < 0.05) for the two cycles analysed; but, only H.L. for S (7.9 cm) was larger (P < 0.05) than for E. Some variables (specially R.C.; A.L.; and H.L.), in ah or some of the alternatives, presented different values from those reported in the hiterature revised, for steers similar to those under trial. Carcass conformation (l.C.B.), together with carcass composition (I.C.N.), of the E and S alternatives, showed a lower proportion of fat tissue with respect to muscular tissue; but carcasses of the I alternative, showed an inadecuate fin ishing grade.

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1 Subestación Experimental Cauquenes (INIA), Casilla 165, Cauquenes, Chile.
2 Estación Experimental Quilamapu (INIA). Casille 426. Chillán, Chile.