Subchronic Hepatic Injury Model Of AA Broilers Induced By AFB1 And Curcumin Intervention

Liver,an important detoxification organ,most of the toxins absorbed by the intestine were passed through the process of biotransformation and detoxification.Therefore,liver is also vulnerable to internal and external toxic substances.Aflatoxin B1（AFB1）is one of AF,which has a very strong toxicity.It is an important research goal for us to study the pathogenesis of liver injury induced by AFB1 and to create the protecting hepato drugs with high economic value,high activity and great curative effects.Curcumin is a main active ingredient in Curcuma longa.It is a natural food additive,antioxidant and anti-inflammatory drug.In this experiment,the sub chronic liver injury model induced by AFB1 in AA broilers was established.According to the activities of ALT and AST,liver tissue oxidative stress indexes（GSH-Px、SOD、MDA）and pathological sections in liver as the bases for judging the AFB1 concentration induced liver injury.And observing the clinical symptoms of AFB1 poisoning.Through the intervention of curcumin,analysing the effect of curcumin application on sub-chronic liver injury induced by AFB1.These results provide a solid and fundamental bases for the prevention of AA broilers sub-toxicity induced by AFB1,the research of toxic AFB1 mechanism and the application of curcumin in veterinary clinic.Results:1.Establishment of AFB1-induced subchronic liver injury model in AA broilersContinuous exposure in high dose(5 mg·kg^-1),medium dose(3 mg·kg^-1)and lose dose(1 mg·kg^-1)AFB1 for 28 days,compared with control group,high dose AFB1 group hepatosomatic index significantly increased（P<0.05）,ALT and AST activity were significantly increased（P<0.01）,GSH-Px and SOD activity in liver were obviously decreased（P<0.01）and MDA content in liver was markedly rised（P<0.01）.Results of pathological sections showed that liver structure w as blurred and there are hepatocytes steatosis,structural dissappearance and inflammatory cell infi ltration in AFB1 high dose group.Medium and high dose AFB1 can reduce AA broilers’ weight significantly.It was suggested that the sub-chronic liver injury model could be successfully establis-hed after continuous exposure of 5mg·kg^-1 AFB1 for 28 days.And AFB1 poisoning symptoms and weight decreased could be observed in AA Broilers.2.The effects of curcumin on subchronic liver injury induced by AFB1 in AA broilersIn this experiment,the clinical symptoms,liver index,serum transaminase activity,biochemical indexes and histopathological analysis of liver tissue were determined to evaluate the intervention effect of different dose curcumin groups(150 mg·kg^-1,300 mg·kg^-1 and 450 mg·kg^-1)on the injury of AA broiler subchronic liver induced by AFB1.After curcumin intervention 28 d,compared with the AFB1 model group,AFB1 poisoning clinical symptom in AA broilers reduction,the average daily gain increased,liver injury significantly reduced.The alleviate degree of liver injury was dose-dependent with curcumin.It indicated that curcumin has protective effect on AA broilers subchronic liver injury induced by AFB1 in the condition of continuous exposure and curcumin intervention.Stop poisoning and curcumin intervention,compared with the control group,livers in AFB1 model group still has significant liver injury,which did not reduce compared to 28 d at 35 d.High dose of curcumin can effectively antagonize the post-toxicity of AFB1.It suggested that high dose curcumin has post-effect,can alleviate AFB1 toxicity.The result showed that the sub-chronic liver injury model could be successfully established after continous exposure of 5 mg·kg^-1 AFB1 for 28 days.The curcumin could effectively antagonize AFB1-induced AA Broiler sub-chronic liver injury,play a protection role.In particular,the protective effect of high dose curcumin is more durable,which can effectively relieve the toxicity of AFB1.The proposed intervention dose is 450 mg·kg^-1.