- 期刊
閹公雞、復陽雞及公雞之屠體及肌肉物理性狀比較
Comparison of carcass traits and muscle physical properties of capon, slip and intact birds in Taiwan country chicken cockerels
摘要
本試驗旨在比較閹公雞、復陽雞及公雞間之屠宰率、屠體部位與器官比例及肌肉物理性狀之差異。試驗選用畜試土雞台畜肉十三號公雞，雞隻於10週齡去勢，並餵給生長期飼料（10－18週齡）及肥育期飼料（19－28週齡）。於28週齡時再將閹公雞處理組，依雞冠有無再度發育，分為閹公雞組與復陽雞組。雞隻經24小時禁食後，進行個別雞隻秤重，每處理組逢機犧牲16隻。試驗結果顯示，屠宰率、腹脂、心臟、腿部、背部及胸部比例，於三者間呈顯著（P＜0.05）差異。屠宰率、心臟及腿部比例以公雞為最高，閹公雞為最低，而腹脂、背部及胸部比例，以閹公雞為最高，公雞為最低。閹公雞之頭頸比例顯著（P＜0.05）較復陽雞或公雞為低。翅膀及腸道比例，則以閹公雞顯著（P＜0.05）較復陽雞或公雞為高。閹公雞之脾臟比例顯著（P＜0.05）較復陽雞為低。公雞之腳部比例顯著（P＜0.05）較閹公雞為高。胸寬、砂囊及肝臟比例於三者間無顯著差異。閹公雞之肌纖維直徑及面積顯著（P＜0.05）較公雞為細且小。閹公雞肌肉之韌度顯著（P＜0.05）低於公雞，但肌肉之咀嚼性及彈力於三者間無顯著差異。綜合本試驗之結果顯示，雞隻去勢會影響屠宰率、屠體部位與器官比例及肌肉物理性狀。復陽雞各性狀之表現則介於閹公雞或公雞間。
並列摘要
An experiment was carried out to compare dressing, carcass part and organ ratios and muscle physical properties of capons, slips and intact birds in Taiwan country chicken cockerels. One hundred and seventy-six Taiwan country chicken cockerels were randomly assigned to caponized or intact male groups. Caponized birds were surgically altered at 10 weeks old and raised to 28 weeks old. At 28 weeks of age, the capons were separated into capon and slip groups, depending on the atrophy of the comb and wattle in size, after 24 h of feed deprivation, 16 birds from each group, were weighted, sacrificed and cut. The results showed that intact birds had the highest (P ＜ 0.05) dressing, heart and thigh ratios and the lowest (P ＜ 0.05) abdominal fat, back and breast ratios followed by slips and capons. The percentage of head and neck were significantly (P ＜ 0.05) greater in the intact birds and slips, while the capons had a greater (P ＜ 0.05) percentage of intestine and wing. Compared with capons, intact birds had a significantly (P ＜ 0.05) greater feet ratio. In addition, the spleen ratio in the capons was significantly (P ＜ 0.05) lower than in the slips. Breast width, gizzard and liver ratios were not affected by the treatments. However, the capon had the smallest (P ＜ 0.05) muscle toughness, muscle fiber diameter and area followed by slips and intact birds, but was not significantly different in the muscle elasticity and chewiness. Moreover, our findings also indicate that the castration resulted in a significant alteration in carcass and organ traits and muscle physical properties.