Effects of Antimicrobial Peptide PR39 on Performance,Serum Immune Indexes and Intestinal Microflora of Weaner Piglets

This experiment was conducted to investigate the effects of antimicrobial peptide PR39 on performance,serum immune indexes and intestinal microflora of weaner piglets.A total of 120 weaner piglets at 28days of age with the similar body weight were randomly allotted into 4 groups with 3 replicates per group and10 piglets per replicate(half male and half female).The piglets in control group were fed a basal diet,those in experimental group Ⅰ were fed the basal diet+120 mg/kg kitasamycin,those in experimental group Ⅱ were fed the basal diet+200 mg/kg ntimicrobial peptide cecropin,and those in experimental group Ⅲ were fed the basal diet+300 mg/kg antimicrobial peptide PR39.The experiment lasted for 21 days.The results showed as follows:compared with control group,the two kinds of antimicrobial peptides both significantly increased average daily gain of piglets,while significantly reduced feed to gain ratio and diarrhea rate(P0.05).Compared with control group,the two kinds of antimicrobial peptides both significantly increased serum immunoglobulin G content(P0.05),serum immunoglobulin M content in experimental group Ⅱ was significantly increased(P0.05),serum immunoglobulin A,complement 3 and 4 contents tended to be increased(P 0.05).Compared with control group,the two kinds of antimicrobial peptides both significantly reduced the number of Escherichia coli in cecum,colon and rectum(P0.05),while the number of Bifidobacterium in cecum in experimental group Ⅱ was significantly increased(P0.05).In conclusion,the dietary supplementation of antimicrobial peptides can improve performance of weaner piglets,decrease the diarrhea rate,increase serum immunoglobulin contents,and stimulate beneficial bacteria proliferation,but inhibit pathogenic bacteria proliferation.