Carcass characteristics and economic profitability of Xinong Saanen male kids under different slaughter ages in intensive production systems

摘要

Abstract The aim of the study was to evaluate the effect of slaughter age on growth performance,carcass characteristics and profitability of Xinong Saanen male kids.A total of 96 kids were selected from three slaughter ages over four years (2010–13).The kids were assigned to three treatment groups,slaughter at 8 months (T1),10 months (T2) and 12 months (T3).T1 had significantly (P＜0.05) higher average daily gain (0.11±0.02) than T2 (0.1±0.04) and T3 (0.08±0.01).There was no significant difference of slaughter weight and total weight gain between T2 and T3.The effect of slaughter age on edible non carcass weights (liver and gall bladder,empty intestines,non-carcass fat and testes) were significant difference (P＜0.05).The percentage of lean,bone and fat were significantly affected by age at slaughter (P＜0.01),carcass lean had highest (62.8％) and lowest (59.8％) percentage in T1 and T3,respectively.T2 showed significantly (P＜0.01) higher bone percentage than T1 and T3,the percentage of fat increased significantly (P＜0.01) with increasing slaughter age.In addition,slaughter age affected the net profit,the marginal cost tend to be higher than marginal revenue after 8 months of age.In conclusion,based on carcass characteristics,the best finishing weights for intact Xinong Saanen male kids is 8 months of slaughter age.To our knowledge this is the first study conducted on dairy male kids,it will contribute in understanding the growth performance and carcass characteristics of dairy kids as related to age and in making wise decisions from economic standpoints.