酵母多糖对断奶仔猪生长性能、肠道形态和肠道免疫状态的影响

Effects of Yeast Polysaccharide on Growth Performance,Intestinal Morphology and Intestinal Immune Status of Weaned Piglets

本试验旨在研究酵母多糖对断奶仔猪生长性能、肠道形态、抗氧化能力和肠道免疫状态的影响。试验选取体重[(6.89±0.88)kg]相近、健康状况良好的21日龄长×大×杜杂交阉公断奶仔猪32头,随机分为4个组,每组8个重复,每个重复1头猪。对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮中添加0.1%酵母多糖(0.1%酵母多糖组)、0.2%酵母多糖(0.2%酵母多糖组)、55 mg/kg吉他霉素和20 mg/kg硫酸黏菌素(抗生素组)的试验饲粮。预试期3 d,正试期28 d。结果表明:与对照组相比,1)饲粮中添加0.1%酵母多糖可显著增加断奶仔猪的平均日增重和平均日采食量(P<0.05),显著降低盲肠内容物pH(P<0.05);添加0.1%和0.2%酵母多糖和抗生素可显著降低料重比(P<0.05);2)饲粮中添加0.1%和0.2%酵母多糖有增加断奶仔猪空肠绒毛高度的趋势(0.05<P<0.10),添加0.1%酵母多糖和抗生素可显著增加回肠上皮内淋巴细胞数量(P<0.05);3)饲粮中添加0.2%酵母多糖和抗生素可显著降低断奶仔猪的十二指肠黏膜超氧化物歧化酶(SOD)活性(P<0.05),添加0.1%、0.2%酵母多糖和抗生素可显著降低空肠黏膜SOD活性(P<0.05);4)0.2%酵母多糖组断奶仔猪的十二指肠黏膜白细胞介素-6(IL-6)的mRNA表达量显著降低(P<0.05),回肠黏膜白细胞介素-10(IL-10)的mRNA表达量显著提高(P<0.05);0.1%、0.2%酵母多糖组和抗生素组的空肠黏膜肿瘤坏死因子-α(TNF-α)的mRNA表达量有降低趋势(0.05<P<0.10)。综上所述,酵母多糖可提高断奶仔猪的生长性能,降低盲肠pH,改善肠道形态并降低肠道炎症。在本试验条件下,仔猪饲粮中酵母多糖的适宜添加水平为0.1%。

This study was conducted to investigate the effects of yeast polysaccharide on growth performance,intestinal morphology,antioxidant capacity and intestinal immune status of weaned piglets.Thirty-two healthy Landrace×Yorkshire×Duroc castrated male weaned piglets at 21-day-old with similar body weight of(6.89±0.88)kg were randomly divided into 4 groups with 8 replicates per group and 1 pig per replicate.Pigs in control group were fed a basal diet,and the others in experimental groups were fed the basal diets supplemented with 0.1%yeast polysaccharide(0.1%yeast polysaccharide group),0.2%yeast polysaccharide(0.2%yeast polysaccharide group)and 55 mg/kg kitasamycin and 20 mg/kg colistin sulfate(antibiotic group).The pretest lasted for 3 days,and the test lasted for 28 days.The results showed as follows:compared with control group,1)diet supplemented with 0.1%yeast polysaccharide significantly increased average daily gain and average daily feed intake of weaned piglets(P<0.05),and significantly decreased pH of cecal content(P<0.05).Diet supplemented with 0.1%and 0.2%yeast polysaccharide and antibiotic significantly deceased the ratio of feed to gain(P<0.05).2)Diet supplemented with 0.1%and 0.2%yeast polysaccharide had a tendency to increase jejunal villus height of weaned pigs(0.05<P<0.10).The number of ileal intraepithelial lymphocytes in 0.1%yeast polysaccharide and antibiotic group was significantly increased(P<0.05).3)Diet supplemented with 0.2%yeast polysaccharide and antibiotic significantly decreased the activity of superoxide dismutase(SOD)in duodenal mucosa of weaned pigs(P<0.05).Diet supplemented with 0.1%and 0.2%yeast polysaccharide and antibiotic significantly decreased the activity of SOD in jejunal mucosa of weaned pigs(P<0.05).4)The expression level of interleukin-6(IL-6)mRNA in duodenal mucosa of weaned pigs in 0.2%yeast polysaccharide group was significantly decreased(P<0.05),and the expression level of interleukin-10(IL-10)mRNA in ileal mucosa in 0.2%yeast polysaccharide group was significantly increased(P<0.05).The expression level of tumor necrosis factor-α(TNF-α)mRNA in jejunal mucosa in 0.1%and 0.2%yeast polysaccharide and antibiotic groups had a tendency to reduce(0.05<P<0.10).It is concluded that yeast polysaccharide can improve growth performance of weaned piglets,reduce the pH value in cecum,improve intestinal morphology and reduce intestinal inflammation.Under the conditions of this experiment,the appropriate supplemented level of yeast polysaccharide in piglet’s diets was 0.1%.