Effects of Gender and Age on Performance and Harvest Traits of Boer × Spanish Goats

Abstract

Cameron. M.R., Hart, S.P., Sahlu, T., Gilchrist, C., Coleman, S.W. and Goetsch, A.L. 2001. Effects of gender and age on performance and harvest, traits of Boer × Spanish goats. J. Appl. Anim. Res., 20: 141–155. Sixty Boer × Spanish goats ware used to determine, effects of gender and age on performance and harvest triats. Wethers, females and males (16.8, 15.6 and 16.9 kg initial body weight, respectively) consumed a high concentrate diet from 116 to 340 d of age, with harvest at. 56-d intervals. Average dry matter intake for the entire experiment was lowest among genders for females (671, 534 and 682g/d; P<0.05) and average daily gain was greater for males and wethers than for females (119, 89 and 138 g/d for wethers, females and males, respectively; P<0.05). Dressing percentage was similar among genders and lowest among ages at. 116 d (41.7, 48.5, 49.9, 51.3 and 50.9% for 116, 172, 228, 281 and 340 d, respectively; P<0.05). internal fat mass was lower (P<0.05) for males than for wethers and females (5.1, 6.9 and 7.0% empty body weight, respectively) and increased with age (2.3, 5.4, 6.3, 7.7 and 9.9% empty body weight; 0.32, 1.08, l.60, 2.77 and 1.08 kg at ll6, 172, 228 and 340 d of age, respectively). Carcass scores and grades were similar among genders. Among genders, males had the greatest (P<0.05) carcass percentages of separable bone (27.1, 27.0 and 29.4%) and lean (50.1, 49.7 and 54.1%) and were lowest in fat (18.0, 19.5 and 12.7% for wethers, females and males, respectively). Carcasses were having 38.9, 29.9, 27.0, 22.6 and 20.7% hone; 0.7, 18.3, 15.1, 21.0 and 22.4% fat; and 49.4, 48.5, 50.9, 53.9 and 53.8% lean at 116, 172, 228, 284 and 340 d, respectively. In summary, differences among genders of Boer crossbred goats in performance and harvest traits were not influenced by age between approximately 4 and 11 mo. However, changes in carcass characteristics differed between 4 and 6 mo of age more than from 6 to 11 mo; and mass of internal fat increased with age and was nearly as great, as that of carcass fat at each age.