抗菌肽对断奶仔猪生长性能、免疫机能及粪便微生物菌群的影响

Effects of antimicrobial peptides on growth performance,immune function and fecal microflora of weaned piglets

为研究添加不同水平的抗菌肽对断奶仔猪生长性能、免疫机能及粪便微生物菌群的影响,采用单因素随机设计试验,选择体重相近的28日龄"杜×长×大"三元杂交断奶仔猪60头随机分成4组,每组15个重复,每个重复1只,1组为对照组饲喂基础日粮,试验2、3、4组分别添加0.5、1.0、1.5 g/kg的抗菌肽,试验期为28 d,在试验结束后测定其生长性能、免疫机能及粪便微生物菌群结构。结果表明:(1)试验3、4组的试验末重、平均日增重均显著高于1组(P<0.05),试验2、3、4组的平均日采食量均高于1组,差异性不显著(P>0.05),试验3、4组的料重比、腹泻率均显著低于1组(P<0.05);(2)试验3、4组血清中的IgG、IgA、IL-2含量均显著高于1组(P<0.05),试验2、3、4组血清中的IgM、IL-6含量均高于1组(P>0.05);(3)试验3、4组粪便中大肠杆菌的含量显著低于1组(P<0.05),试验2、3、4组粪便中沙门菌的含量均低于1组(P>0.05),试验3、4组粪便中双歧杆菌和乳酸杆菌的含量显著高于1组(P<0.05)。说明1.0 g/kg抗菌肽添加可以提高断奶仔猪生长性能和免疫机能,改善肠道菌群结构平衡。本研究为抗菌肽进一步的临床应用奠定基础。

In order to study the effects of different levels of antimicrobial peptides on growth performance,immune function and fecal microflora of weaned piglets,6028-day-old"Duloc×Landrace×Yorkshine"three-way crossbred weaned piglets with similar weight were randomly divided into four groups,15 replicates in each group,1 in each replicate.Group 1 was fed with basic diet as the control group.Antimicrobial peptides of 0.5,1.0,1.5 g/kg were added in groups 2,3 and 4,respectively for 28 days.At the end of the experiment,growth performance,immune function and faecal microbial flora structure were measured.The results showed that:(1)The final weight and average daily gain of groups 3 and 4 were significantly higher than those of group 1(P<0.05).The average daily feed intake of groups 2,3 and 4 was higher than that of group 1(P>0.05).The feed-weight ratio and diarrhea rate of groups 3 and 4 were significantly higher than that of group 1(P<0.05);(2)The serum IgG,IgA and IL-2 contents of groups 3 and 4 were significantly higher than that of group 1(P<0.05).The levels of IgM and IL-6 in serum of groups 2,3 and 4 were higher than those of group 1(P>0.05);(3)The levels of E.coli in feces of groups 3 and 4 were significantly lower than those of group 1(P<0.05).The levels of Salmonella in feces of groups 2,3 and 4 were lower than those of group 1(P>0.05).The contents of Bifidobacterium and Lactobacillus in feces of groups 3 and 4 were significantly higher than those of group 1(P<0.05).The results indicated that 1.0 g/kg antimicrobial peptide could improve the growth performance and immune function of weaned piglets,and improve the structure balance of intestinal flora.This study lays a foundation for the clinical application of one-step antimicrobial peptide.