作　　者： ; ; ;

机构地区： 中国农业科学院北京畜牧兽医研究所动物营养学国家重点实验室

出　　处： 《畜牧兽医学报》 2008年第6期827-831,共5页

摘　　要： 选择体重相近、健康的5周龄AA肉鸡公鸡和北京油鸡公鸡各108只,评价持续高温对其生产性能、胴体组成、脂肪沉积的影响,比较其对高温耐受性的差异。试验设3个处理:34℃持续高温,自由采食(试验组,34AL);21℃适温,自由采食(适温对照组,21AL);21℃适温,采食量与34AL组相同(采食配对组,21PF)。所有仔鸡在人工环控舱饲养至8周龄试验结束。结果表明:AA肉鸡在持续高温下的采食量比适温对照组降低45%(P<0.001),日增重由61.45 g/d降至22.29 g/d(P<0.001),饲料利用率明显降低(P<0.05)。对北京油鸡而言,热暴露虽然也使采食量大幅下降(下降幅度为20%,P<0.001),但日增重却没有受到高温的影响,饲料利用率明显提高(P<0.05)。北京油鸡在试验期间无一死亡,而高温处理的AA肉鸡死亡率高达36%。与适温对照组相比,高温试验组AA肉鸡的胸肌率明显下降(P<0.05),肌间脂肪和皮下脂肪的沉积率明显降低(P<0.01),腹脂沉积率无明显变化(P>0.05)。北京油鸡胸肌率未受到高温的影响,但热暴露北京油鸡腹脂沉积率明显高于适温对照组(P<0.05),肌间脂肪和皮下脂肪的沉积相对稳定(P>0.05)。研究表明,北京油鸡对高温表现出极高的耐受性,在持续34℃高温下正常的生长、发育没有受到影响;AA肉鸡在持续34℃高温下,正常的生长、发育被极大程度地破坏,死亡率高。北京油鸡适应高温的调节机制可能与其在高温下腹脂沉积增加及饲料利用率提高有关。 The effects of chronic heat stress on growth, carcass traits and fat deposition were investigated in two breeds of broilers. Male chickens （108, 5 wk old） from Arbor Acres （AA） and Beijing-You （BJY） respectively were equally distributed to 3 treatments： constant high ambient temperature at 34℃ with ad libitum feeding （34AL）, constant optimal ambient temperature at 21℃ with ad libitum feeding （21AL）, and constant optimal ambient temperature 21℃ but pairfed to the amount consumed by the 34AL group （21PF）. The results showed that under hot condition, for AA broilers, the feed intakes were decreased by 45G （P〈0. 001）and average daily gain （ADG） were decreased from 61.45 g/d to 22.29 g/d, the feed efficiency decreased significantly. While for BJY chickens, their growth were not affected by high temperature even though the feed intake were decreased. The mortality of heat-stressed AA broilers was 36% but all of the BJY groups survived the experimental feeding period. The breast muscle rate and fat deposition of heat-stressed AA broilers were decreased significantly. While the breast muscle rate of BJY chickens were not affected by high temperature and abdominal fat deposition rate of BJY chickens was enhanced by heat stress （P〈0.05）. The data indicated that BJY chickens had higher resistance to extreme heat comparing with AA broilers which got bad growth performance under high temperature. The higher feed efficiency and enhanced abdominal fat deposition rate would account for the high adaptability to extreme heat in BJY chickens.

关 键 词： 热应激 生长 胴体性状 脂肪沉积 肉鸡

领　　域： [农业科学] [农业科学]