37℃持续热应激肉鸡血气改变的动态分析  

Dynamic Blood Gas Analysis of Broiler Chickens Under 37℃ Constant Heat-stress

作　　者：李静[1] 乔健[1] 高铭宇[1] 欧德渊[1] 邹淑梅[1] 王慧煜[1] 

机构地区：[1]中国农业大学动物医学院,北京100094

出　　处：《畜牧兽医学报》2005年第5期471-475,共5页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：国家自然科学基金资助项目(30070567)

摘　　要：80只25日龄雄性AA肉鸡,随机分为对照组(21~24 ℃,相对湿度50%±5%)和试验组(37 ℃±0 5 ℃,相对湿度70%±5%),自由采食和饮水。在12 d的试验期间,动态检测血气指标、呼吸频率、直肠温度和生产性能的变化。结果显示:热暴露初期呈现代偿性呼吸性碱中毒,其特点为动脉血二氧化碳分压(3.82±0 36)降低,pH(7.48±0 04)升高;中期呈现失代偿性代谢性酸中毒,其特点为血浆HCO-3 浓度(19.00±2.55)降低,pH(7.37±0 06)显著下降(P<0 05);后期酸碱平衡趋于正常。热应激后,肉鸡日增重和日采食量极显著下降(P<0 01)、料肉比极显著升高(P<0 01);呼吸频率极显著升高(P<0 01);热暴露第1、5、7、9 和12 天体温极显著升高(P<0 01)。动脉血氧分压与呼吸频率呈极显著负相关(P<0 01),与体温呈显著负相关(P<0 05);血氧饱和度与体温极显著负相关(P<0 01)。表明37 ℃持续热应激的肉鸡呈现由代偿性呼吸性碱中毒转变为失代偿性代谢性酸中毒,最后趋于正常的动态变化过程。Eighty 25-day-old male AA broilers were divided randomly into two groups (40×2): the control group (21～24℃, 50%±5% relative humidity) and thermostress group ((37±0.5) ℃,70%±5%relative humidity). The blood gas analysis, respiration rate, rectal temperature and production performance of broiler chickens were examined continuously.In thermostress group, 24 hours treatment induced a compensated respiratory alkalosis, which was characterized by the decreased partial pressure of CO_2 (PaCO_2)and the increased pH in artery; about 6 days later there was a decompensated metabolic acidosis, which was characterized by the dropped arterial blood bicarbonate ion (HCO^-_3) and the decreased pH value (P<0.05); 12 days after thermostress acid-base balance was almost resumed. Body weight gain and feed intake of thermostressed chickens were decreased significantly (P< 0.01), and feed/gain was increased significantly (P<0.01). The respiration rate and rectal temperature of heat-stressed broiler chickens were increased significantly (P<0.01) at 1, 5, 7, 9 and 12 days after thermostress. The oxygen partial pressure (PaO_2) had a significantly negative correlation with respiration rate (P<0.01) and rectal temperature (P<0.05). The arterial blood oxygen saturation(SaO_2)had a significantly negative correlation with rectal temperature (P<0.01). These results showed that there are the significant acid-base balance disturbance, the severely affected physiological function and decreased production performance in the broiler chickens under 37℃ constant heat-stress.

关 键 词：热应激 动态分析 代谢性酸中毒 呼吸频率 二氧化碳分压 相对湿度 血氧饱和度 负相关 AA肉鸡 自由采食 血气指标 动态检测 生产性能 直肠温度 酸碱平衡 日采食量 变化过程 碱中毒 呼吸性 热暴露 试验组 试验期 日增重 料肉比 

分 类 号：S858.31[农业科学—临床兽医学] S858.292[农业科学—兽医学]