Carcass characteristics of male Alpine kids slaughtered at different weights

Abstract

With a view to increasing meat yield by changing slaughter weight, this research has been carried out to evaluate variations in dressing percentage, carcass and meat quality, and fat composition in male Alpine kids. Sixty-six kids were used: Group 1 (20 animals) was slaughtered at the weight of 11.8 ± 0.15 kg, Group 2 (20 animals) at 15.7 ± 0.08 kg and Group 3 (26 animals) at 19.4 ± 0.22 kg. Animals were fed milk-replacer and, from the 11th day, a diet consisting of 70% concentrate mixture and 30% wheat bran. Main ingredients of milk replacer were dried skim milk (not less than 60%), fat (tallow and coconut oil), dried whey from sheep milk. Composition, on a dry matter basis, was 24.9% crude protein, 25.2% crude fat, 0.9% crude fibre, 6.8% ash, 42.2% N-free extract and 4.22 Mcal/kg metabolizable energy. Main ingredients of the concentrate mixture were grains, soybean oil meal, molasses, carob meal and minerals. The composition was 21.9% crude protein, 4.9% crude fat, 7.7% crude fibre, 7.9% ash, 57.6% N-free extract and 3.38 Mcal/kg metabolizable energy. The left side of all animals was divided into fore and rear quarters. Moisture content and area of longissimus dorsi muscle and fatty acid composition of fat were determined. The most interesting results for (a) the dressing percentage (carcass/empty liveweight); (b) the longissimus dorsi area and (c) the saturated/unsaturated fatty acid ratios were for Groups 1, 2 and 3: a) 55.30, 57.50 and 56.50% (1 vs. 2: P < 0.05); b) 4.50, 6.16 and 6.55 cm (2 and 3 vs. 1: P < 0.01); c) for sternal fat 0.707, 0.694 and 0.612; for inguinal fat 0.884, 0.826 and 0.728. Overall results suggest that slaughter weight of kids should be increased from the present 8–10 kg to 15–16 kg in order to improve dressing percentage, loin muscle size and the proportion of unsaturated fatty acids in sternal and inguinal fat.