热应激条件下藿朴蒲苓散对育肥羔羊生长性能、消化性能和血清生化指标的影响

针对夏季绵羊遭受严重热应激现状，研究日粮中添加中草药组方(藿朴蒲苓散)对夏季育肥羔羊生长性能、消化性能、瘤胃发酵参数及血清生化指标的影响。选择200只体重相近、年龄一致的健康育肥公羔羊，随机分为4组，分别饲喂0%(对照组)、0.5%、1.0%和1.5%藿朴蒲苓散，试验期30 d，试验期间舍内温湿指数平均达79.11。试验末检测育肥羔羊生长性能、养分表观消化率、瘤胃发酵参数和血清生化指标。结果表明：1)饲喂0.5%藿朴蒲苓散的羊日增重显著高于对照组(P < 0.01)；日饮水量和日采食量在不同组间未表现出显著性差异(P>0.05)。从生理指标分析，饲喂中草药的羊直肠温度和呼吸频率与对照组比较均未表现出显著性差异(P>0.05)。2)0.5%组的干物质(DM)、中性洗涤纤维、酸性洗涤纤维、粗蛋白、钙和磷等养分表观消化率均显著高于对照组(P < 0.05)，DM消化率较对照组提高7.20%(P < 0.01)，而1.0%和1.5%组的消化率较对照组未表现出显著性差异(P>0.05)。3) 从血清生化指标上，3个给药组的生长激素均显著高于对照组(P < 0.05)，0.5%组含量最高，较对照组提高16.90%；且0.5%组的甲状腺素含量显著高于其他组(P < 0.05)。4)从瘤胃发酵参数分析，3个给药组总挥发性脂肪酸含量、乙酸和丁酸含量均显著高于对照组(P < 0.05)，分别是对照组的1.19~1.30倍、1.18~1.24倍和1.28~1.43倍。综上，本试验条件下，日粮中添加藿朴蒲苓散有助于缓解育肥羔羊的热应激，添加量以0.5%效果更佳。

Effects of Huopopuling Powder on Growth Performance,Digestibility and Serum Biochemical Indexes in Fattening Lambs under Heat Stress

Sheep are suffering from severe heat stress in summer recently, and present study was conducted to investigate the effect of Chinese herbal formulation (Huopopuling Powder) in diet on growth performance, digestibility, rumen fermentation parameters, and serum biochemical indexes in fattening lambs in summer. A total of 200 fattening lambs with similar body weight and the same age were selected and randomly divided into 4 groups, which were fed with 0% (control group), 0.5%, 1.0%, and 1.5% of Huopopuling Powder. The experimental period were lasted for 30 days, and the temperature and humidity index in experimental shed averaged 79.11. The growth performance of fattening lambs, apparent nutrient digestibility, rumen fermentation parameters, and serum biochemical indexes were detected at the end of the experiment. The results were showed as follows: 1) The daily weight gain of lambs fed 0.5% Huopopuling Powder was higher than that of the control (P < 0.01). There was no significant difference in daily water intake and daily feed intake among all groups (P>0.05). For physiological parameter, the rectal temperature and respiratory rate of lambs fed with Huopopuling Powder showed no significant difference compared with the control (P>0.05). 2) The apparent digestibility of nutrients involving dry matter (DM), neutral detergent fiber, acid detergent fiber, crude protein, calcium and phosphorus was higher in 0.5% group than that in the control (P < 0.05). The DM digestibility increased by 7.20% in 0.5% group compared with the control (P < 0.01), while the digestibility in 1.0% or 1.5% group exhibited no significant difference compared with the control (P>0.05). 3) For serum biochemical indexes, growth hormone content was higher in the three Huopopuling-fed groups than that in the control (P < 0.05); Among all groups, the content was the highest in 0.5% group, showing 16.90% higher than that in the control. While thyroxine content in 0.5% group significantly increased compared with other groups (P < 0.05). 4) From analysis of rumen fermentation, fermentation parameters in three Huopopuling supplementation groups demonstrated an increase ranged from 1.19 to 1.30 times in total volatile fatty acid, 1.18 to 1.24 times in acetic acid, and 1.28 to 1.43 times in butyric acid than those in the control (P < 0.05). The results indicate that under the condition of this study, Huopopuling Powder could effectively alleviate heat stress of fattening lambs and its appropriate dose is suggested for 0.5% in diet.