Effect Of Fly Maggot Antimicrobial Peptide Combined With Astragalus Polysaccharide On Immune Performance Of Yellow-feather Broilers

Objective: to provide green and healthy additives for animal production.Yellow feathered broilers were fed with fly maggot powder combined with astragalus polysaccharide.The feed intake,daily gain,serum immune biochemical indexes and intestinal flora quantity of the tested chickens were measured,and the combined effects of fly maggot powder and Astragalus Polysaccharide on immune and growth performance of animals were analyzed.Methods: daily gain and feed intake of yellow feathered broilers were measured,and the effects of fly maggot powder combined with Astragalus Polysaccharides on growth performance and slaughter performance were analyzed;serum immune biochemical indexes were detected by ELISA kit;intestinal flora was counted by plate counting method;intestinal mucosal lymphocytes and goblet cells were measured by paraffin section method;The expression of intestinal mucosal factors(TGF-β4 and TNF-αm RNA)was detected by Q RT-PCR.Results:1.The average daily gain rate(P<0.05)was significantly higher than that of the control group(P<0.05)In the powder group(P<0.05),the feed to weight ratio(F/g)was significantly lower than that of the control group(P<0.01),significantly lower than that of the maggot powder group(P<0.05),and the body weight before slaughter was significantly higher than that of the control group(P<0.05);there was no significant difference in the bloodletting weight,slaughter rate,eviscerated rate,half eviscerated rate and chest muscle rate among the experimental groups(P>0.05);the leg muscle rate of broilers in the fly maggot powder combined with astragalus polysaccharide group was significantly higher than that in the control group The protein apparent metabolic rate of the control group was higher than that of the other groups(P< 0.01).2.The serum total protein content of broilers in the fly maggot powder combined with astragalus polysaccharide group was higher than that of the control group,fly maggot powder group,astragalus polysaccharide group and antibiotic group,but there was a significant difference between the two groups(P<0.05),and the albumin concentration was significantly higher than that of the control group,maggot powder group and antibiotic group(P<0.01).The contents of Ig G and Ig M in fly maggot powder combined with astragalus polysaccharide group were significantly higher than those in control group,maggot powder group,astragalus polysaccharide group and antibiotic group(P<0.01).The number of E.coli in duodenum,jejunum and ileum of broilers in each experimental group was significantly lower than that in the control group(P<0.01),and the number of Lactobacillus in duodenum,jejunum and ileum of the experimental groups was significantly lower than that of the control group(P<0.01),and the number of Lactobacillus in the duodenum,jejunum and ileum of the experimental groups was higher than that of the control group(P<0.01)Except for duodenum,the number of Lactobacillus in jejunum and ileum was significantly higher than that in maggot powder group and astragalus polysaccharide group(P<0.01).The number of lymphocytes and goblet cells in duodenum,jejunum and ileum of broilers was significantly higher than that of control group and antibiotic group(P<0.01),and that of maggot powder combined with astragalus polysaccharide group was significantly higher than that of maggot powder group and astragalus polysaccharide group(P<0.01).There was no significant difference in the expression of TGF-β4 in duodenum of broilers(P>0.05);in jejunum,the expression of TGF-β4 in myiasis powder group was lower than that in control group and astragalus polysaccharide group(P<0.05);in ileum,the expression level of TGF-β4 in myiasis powder group was lower than that in control group and astragalus polysaccharide group(P<0.01);in ileum,maggot powder group was lower than that in Astragalus polysaccharide group and antibiotic group(P<0.01).TNF-ɑ in duodenum and jejunum was higher than that in control group,but lower in ileum.Conclusion: The combination of fly maggots powder and astragalus polysaccharide can improve the growth performance and immune performance of yellow feather broiler and the combination of the two is better than that of single addition,which indicates that fly maggots powder combined with astragalus polysaccharide can be used as green feed additive in animal production.