研究旨在探讨饲粮添加异亮氨酸(isoleucine,Ile)对断奶仔猪生长性能、血清生化指标和肠道微生物的影响.选取体重为(7.82±0.52)kg的杜×长×大健康仔猪180头,随机分为6个处理,每个处理6个重复,每个重复5头仔猪.6组试验猪分别饲喂含0.78%(对照组)、0.87%、0.94%、1.01%、1.09%、1.16%Ile水平的饲粮.试验期为21 d.结果表明:饲粮Ile水平对断奶仔猪的平均日采食量、平均日增重和饲料转化率均无显著影响(P>0.05).当饲粮中Ile水平为1.01%时,仔猪血清中免疫球蛋白A(IgA)水平显著高于0.87%、0.94%、1.09%、1.16%Ile水平(P<0.05).饲粮Ile水平为0.94%时,尿素(UREA)水平显著高于0.78%Ile水平(P<0.05).同时,当饲粮Ile水平为1.01%时,与0.78%Ile水平相比,提高了有益菌Norank_f_norank_o_Clostridia_UCG_014的丰度,增加了断奶仔猪肠道健康.综上所述,饲粮Ile水平对断奶仔猪的生长性能无影响,与0.87%Ile水平相比,1.01%Ile水平可以显著提高断奶仔猪的血清免疫水平和肠道有益微生物丰度.在本试验条件下,推荐8~17 kg断奶仔猪饲粮Ile水平为1.01%.
This experiment was conducted to study the effects of isoleucine(Ile)on growth performance,serum biochemical indices and intestinal microbiota of weaned piglets.One hundred and eighty Duroc×Landrace×Yorkshine piglets with an average body weight of(7.82±0.52)kg,were randomly assigned to six treatments with 6 replicates and five pigs per replicate.The piglets received the same basal diet supplemented with 0.78%(control group),0.87%,0.94%,1.01%,1.09%and 1.16%Ile,respectively.The feeding trail lasted for 21 days.The results showed that there were no effects of Ile on average daily food intake,average daily gain,and feed conversion rate(P>0.05).1.01%Ile supplementation increased serum IgA level significantly,compared with 0.87%,0.94%,1.09%,1.16%Ile(P<0.05).Compared with 0.78%Ile,0.94%Ile increased serum UREA significantly(P<0.05).Meanwhile,compared with 0.78%Ile,1.01%Ile increased abundance of beneficial bacterial community of Norank_f_norank_o_Clos-tridia_UCG_014.These results indicated that diet supplemented with Ile had no effect on growth per-formance of weaned piglets,however,when the di-etary Ile level was 1.01%,it significantly im-proved the serum immune level and abundance of beneficial microorganisms in the intestines of weaned piglets.Under the conditions of this experiment,it is recommended to have a dietary Ile level of 1.01%for weaned piglets weighing between 8 and 17 kg.