本試驗旨在探討去勢對雄性台灣黑羽土雞在生長期的血液紅血球相、白血球相、睪固酮濃度、雞冠及尾羽發育之影響。試驗選取體重相近10週齡商業黑羽土雞共24隻，並把雞隻分成對照組（假手術）、摘除1個睪丸及摘除2個睪丸（閹雞）三組，每處理8隻，試驗為期6週，在雞隻12、14及16週齡時，每處理全部雞隻以翼下靜脈採血，分析血液紅血球相、白血球相與血清睪固酮濃度，並在14及16週齡測量雞冠與肉髯高度和寬度及16週齡尾羽長度。結果顯示，公雞經去勢會顯著降低紅血球數目、血紅素濃度與血容比值，且其雞冠與肉髯高度與寬度為最小(P<0.05)，惟摘除單睪丸對上述性狀影響不顯著。摘除單睪丸之雞隻血液睪固酮濃度之平均值為假手術公雞者之69%，顯示摘除單睪丸後可能有補償性睪丸肥大。睪固酮濃度與雞冠或肉髯之發育皆為正相關。從閹雞血液在12及14週齡時，分別有最低的血液異嗜球及最高的淋巴球百分比，以及最低的異嗜球／淋巴球之比值觀之，去勢可減少雄性台灣黑羽土雞在生長期的緊迫。
The objective of this experiment was to study the effects of castration on erythrocyte and leukocyte profiles, testosterone levels in blood and crown development of Taiwan black-feather country cockerels during growing period. Twenty-four 10-weeks old Taiwan black-feather country cockerels with similar body weight were randomly allocated into three groups which were castrated (capon), hemicastrated and sham. At 12, 14, and 16 weeks of age, blood was taken from wing vein for erythrocyte and leucocyte profiles and testosterone levels determinations. The height and width of crown and wattle or tail feather length were measured during 14-16 weeks of age period. Results indicated that Red blood cell, hemoglobin and packed cell volume were the highest in capon; The height and width of crown and wattle or tail length were the lowest in castrated birds among all three groups. And there were no significant difference between sham and hemicastrated groups were observed. There were positive correlation between testosterone level, crown, wattle and tail height, width and length. During the experiment, the average testosterone level in hemicastrated bird was 69% of that in sham birds, assuming that hemicastrated birds mayhave developed a compensatory testicular hypertrophy. Based on the lowest H/L ratio observed in castrated birds, it is concluded that castration may reduce stress in male Taiwan black-feather country cockerels during growing period.
