本试验旨在研究热应激条件下脂肪来源对肉兔生产性能、养分消化率及血清脂质代谢和抗氧化指标的影响。试验选择30日龄的断奶新西兰兔600只，随机分成5个组，每个组6个重复，每个重复20只。对照组饲喂基础饲粮，各脂肪添加组分别饲喂含2%牛油、猪油、玉米油、豆油的饲粮。试验兔均饲养在热应激兔舍（温湿指数为29.5±0.5）中。试验期7周。结果表明：与对照组相比，热应激条件下饲粮中添加不同来源的脂肪均可以显著提高肉兔的平均日增重（P<0.05），显著降低料重比（P<0.05），其中以玉米油的效果最佳。与对照组相比，热应激条件下饲粮中添加不同来源的脂肪均可以显著提高肉兔的干物质和粗蛋白质消化率（P<0.05），显著降低粗脂肪消化率（P<0.05），但对粗灰分和粗纤维消化率无显著影响（P>0.05），其中玉米油组的干物质消化率最高，豆油组的粗蛋白质消化率最高。与对照组相比，热应激条件下饲粮添加牛油或猪油可以显著提高肉兔血清甘油三酯和总胆固醇含量（P<0.05）；玉米油组和豆油组肉兔血清甘油三酯和总胆固醇含量则与对照组差异不显著（P>0.05）。与对照组相比，热应激条件下饲粮添加豆油和玉米油可以显著提高肉兔血清超氧化物歧化酶活性和总抗氧化能力（P<0.05），显著降低血清丙二醛含量（P<0.05）；牛油组和猪油组血清超氧化物歧化酶活性、总抗氧化能力和丙二醛含量则与对照组差异不显著（P>0.05）。由此可见，热应激条件下，饲粮添加不同来源的脂肪均可提高肉兔生产性能及干物质和粗蛋白质消化率，从整体效果来看，玉米油 > 豆油 > 猪油 > 牛油；饲粮添加牛油或猪油可提高肉兔血清甘油三酯和总胆固醇含量，对机体抗氧化能力的影响不显著；饲粮添加豆油或玉米油对肉兔血清甘油三酯和总胆固醇含量无显著影响，但可显著提高机体的抗氧化能力。

This experiment was conducted to evaluate the effects of fat source on performance, nutrient digestibility and serum lipid metabolism and antioxidant indices of meat rabbits under heat stress. Six hundred 30-day-old weaned New Zealand rabbits were randomly divided into five groups, and each group included six replicates and each replicate included 20 rabbits. Rabbits in control group were fed a basal diet, and rabbits in fat addition groups were fed diets contained 2% butter, lard, corn oil and soybean oil, respectively. The experiment lasted for seven weeks, and all rabbits were fed in the rabbit house under heat stress environment (temperature-humidity index was 29.5±0.5). The results showed as follows: compared with control group, diet with different sources of fat under heat stress condition could significantly increase the average daily gain of meat rabbits (P<0.05), significantly decrease the feed/gain (P<0.05), and the corn oil had the best effect. Compared with control group, diet with different sources of fat under heat stress condition could significantly increase the digestibility of dry matter and crude protein (P<0.05), and significantly decrease the digestibility of ether extract, but had no significant effect on the digestibility of ash and crude fibre (P>0.05). The digestibility of dry matter of corn oil group was the highest, and the digestibility of crude protein of soybean oil group was the highest. Compared with control group, diet with butter or lard under heat stress condition could significantly improve the contents of triglyceride and total cholesterol in serum (P<0.05), but the contents of triglyceride and total cholesterol in serum of corn oil group and soybean oil group were not significantly different (P>0.05). Compared with control group, diet with corn oil or soybean oil under heat stress condition could significantly improve the serum superoxide dismutase activity and total antioxidant capacity (P<0.05), and significantly reduce the serum malondialdehyde content (P<0.05), but the serum superoxide dismutase activity, total antioxidant capacity and malondialdehyde content of butter group and lard group were not significantly different (P>0.05). The results indicate that diet with different sources of fat under heat stress condition can increase the performance and the digestibility dry matter and crude protein of meat rabbits, and the overall effect shows corn oil group > soybean oil group > lard group > butte group. Diet with butter or lard under heat stress condition can significantly improve the serum triglyceride and total cholesterol contents, but has no significant effect on the antioxidant capacity of meat rabbits. Diet with corn oil or soybean oil under heat stress condition has no significant effects on the serum triglyceride and total cholesterol contents, but can significantly improve the antioxidant capacity of meat rabbits.