Weight at Slaughter and Carcass Characteristics of Indigenous Castrated Matebele Goats Reared On Range in Zimbabwe

Abstract

A study was conducted to demonstrate that dimensions of carcass parameters and carcass compositions are influenced by adult mature weight at slaughter in castrated indigenous Matebele goats kept on range at Matopos Research Station, Bulawayo, Zimbabwe. Records of carcass parameters of indigenous  Matebele goats from selected mature adults at slaughter, 20 - 24 kg (378 records), 25 - 29 kg (292 records), 30 - 34 kg (283 records), 35 - 39 kg (292 records), 40 - 44 kg (257 records) and >45 kg  (237 records)  were obtained over a period of 15 years (1989 - 2004) and analysed for carcass performance. The goats  reached the selected adult mature weight ranges of 20 - 24, 25 - 29, 30 - 34, 35 - 39, 40 - 44 and >45 kg at 2.03, 2.44, 3.45, 4.50, 4.72 and 6 years of age respectively. Data on performance parameters and weight of organs as a percentage of empty body weight (EBW) containing the effects of the studied adult mature weight ranges were analysed using the General Linear Models (GLM) procedure of the Statistical Analysis System (SAS 1999-2000). The highest hot carcass mass (HCM) averaged 19.50± 0.38 kg for goats slaughtered at >45 kg. There was a significant difference (p<0.01) in cold carcass mass for different adult mature weights at slaughter. The goats slaughtered at weights above 25-29 kg had significantly heavier leg length (LGL), front barrel (FBL) and deep side (DPS) than those slaughtered at 20-24 kg, however there were no differences (p>0.01) amongst adult mature weight at heavier slaughter weights. The goats slaughtered at >45 kg weight had the highest (p<0.01) dressing percentage (DP) and goats slaughtered at 20 - 24 kg of weight had the lowest (p<0.01) DP. The proportion of pelt, kidneys, heart and mesenteric fat were constant. There was a significant (p<0.01) difference between kidney fat amongst groups, which increased with increasing weight. Optimal point of slaughter for castrated Matebele goat on range may be attainable between 25 and 35 kg of adult mature weight at slaughter under range management.