The Protective Effect And Mechanism Of Arctiin On Broiler Chickens Infected With Pullorum

The purpose of this experiment is to investigate the preventive effect of arctiin on Salmonella pullorum infection in broiler chickens.Animal experiments mainly use arctiin on growth performance,immune organ index,intestinal morphology,immune level,and serum endotoxin after Salmonella pullorum infection in broiler chickens.And the effects of diamine oxidase levels,cytokines and cecal intestinal flora to investigate the preventive effect of arctiin on Salmonella pullorum challenge in broilers.In vitro experiments are mainly based on the minimum inhibitory concentration and growth curve of arctiin on Salmonella pullorum,Adhesion rate,biofilm formation ability and metabolic effects,to investigate the mechanism of arctiin on the prevention and treatment of Salmonella pullorum infection in broilers,in order to provide scientific basis for the development of arctiin as an anti-anti-additive.In the experiment,360 1-day-old yellow-feather broiler chicks with healthy and basically the same weight were selected.The experimental chickens were randomly divided into 6 treatment groups,each with 6 replicates,and each replicate with 10 chickens.One control group was fed with basal diet,one challenge group was basal diet + Salmonella pullorum gavage challenge,and the experimental group was ARC100 group(basic diet+100mg/kg arctiin),ARC200 group(Basal diet+200mg/kg arctiin),ARC400 group(basic diet+400mg/kg arctiin),antibiotic group(basic diet+100mg/kg chlortetracycline).The entire test period is 28 days,divided into the early stage of growth performance feeding(1-14 days old)and the late stage(15-28 days old),the early stage of challenge feeding(1-19 days of age),and the late stage of challenge feeding(1-28 Day-old),the experimental chickens are free to eat and drink,23 h light,immunization and daily management are carried out in accordance with routine feeding and management.At the age of 19 days,one test chicken was randomly selected from each replicate and slaughtered and sampled after the blood was drawn;at the age of 28 days,one test chicken was randomly selected from each replicate and slaughtered and sampled after the blood was drawn.The results show:(1)The addition of 200mg/kg arctiin to the basal diet significantly reduced the feed-to-meat ratio of broilers from 1 to 14 days(P<0.05),the feed-to-meat ratio,daily gain,and daily feed intake of broilers.The challenge group and other experimental groups There is no significant difference between them.(2)The level of serum endotoxin in the pre-challenge period was significantly higher in the challenge group and the arctiin 200mg/kg group than the other experimental groups(P<0.05),and there was no significant difference in the other experimental groups(P>0.05),Serum diamine The content of oxidase(DAO)and antibiotics was significantly higher than that of the other experimental groups(P>0.05).Compared with the control group,the level of serum endotoxin(LPS)in the late stage(28d)of the challenge group was significantly increased(P<0.05).In the arctiin addition group,the level of serum DAO in the 100mg/kg group was the lowest,which was comparable to that in the challenge group.There was a significant difference between the groups(P<0.05).(3)There was no significant difference in the morphology of the jejunum and ileum in the experimental groups in the early stage.In the later stage,compared with the experimental groups,the ileal villi of the challenge group were significantly lower than those of the control group and the antibiotic group(P<0.05).Among the arctiin groups,the ileal villi of the200mg/kg arctiin group were the highest,and the ileal crypts of the challenge group Significantly shallower than the control group,antibiotic group and arctiin 200mg/kg group(P < 0.05),the ileal villi crypts were also lower than the challenge group than the other experimental groups,which was significantly different from the antibiotic group(P<0.05).(4)The levels of IgM and IgA between the groups were significantly different 3 days after the challenge(P<0.01).The serum IgM levels in the control group and other experimental groups were significantly higher than those in the challenge group(P<0.05).The levels of IgM and IgG were significantly different between the groups 12 days after the challenge(P<0.05).In the control group,the arctiin 100mg/kg group,the IgM level was significantly higher than the challenge group(P < 0.05),and the IgG level in each experimental group Both were higher than the challenge group,the antibiotic group and the control group were significantly different from the challenge group(P<0.05).(5)After 3days of challenge,compared with the control group,the serum IL-8 and INF-γ levels of the challenge group were significantly reduced(P<0.05).After12 days of challenge,the levels of IL-8,IL-1β,and INF-γ were significantly increased compared with the other experimental groups(P<0.05).In vitro experiments show:(1)Arctiin does not have the activity of inhibiting the growth of Salmonella pullorum,but arctiin can significantly inhibit the adhesion rate of Salmonella pullorum and can significantly affect the formation of Salmonella pullorum biofilm.(2)Through the study of the metabolome blood of Salmonella pullorum,it can be found that arctiin can affect the metabolism of Salmonella pullorum,and 19 different metabolites can be screened.