Alleviation Of Toxic Effects Of Zearalenone By Modified Attapulgite And Vitamin E In Broiler Chickens

This study was conducted to evaluate the toxic effects of zearalenone(ZEA)on the growth performance,serum physiological and biochemical indexes,immunity,liver function of broilers.Also,effects of modified attapulgite and vitamin E supplementation on the growth performance,serum physiological and biochemical indexes,immune and liver function,digestive function,and ZEA residues in the tissues of broilers fed diets contaminated with ZEA were also investigated in order to explore the validity and feasibility of their detoxification effect,which would in turn provide a foundation for the their application.The thesis consisted of 3 parts as follows:Trial 1 was conducted to study the effects of ZEA on serum parameters,hepatic oxidative damage,and ZEA residues in tissues of broilers.A total of 120 chickens were randomly allocated into 2 groups with 6 replicates of 10 birds each,receiving the basal diet or basal diet contaminated with 2 mg ZEA/kg diet.The results showed as follows:1)ZEA decreased total protein(TP)and albumin(ALB)concentrations(P<0.05)whereas increased activities of aspartate aminotransferase(AST),alanine aminotransferase(ALT),and alkaline phosphatase(ALP)in the serum when compared with control group(P<0.05);2)There were no differences(P>0.05)in the concentrations of serum immunoglobulin A(IgA),immunoglobulin G(IgG),immunoglobulin M(IgM),interleukin 2(IL-2),interleukin 5(IL-5)or tumor necrosis factor a(TNF-?);3)ZEA increased concentrations of malondialdehyde(MDA)whereas decreased superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px),and reduced glutathione(GSH)content in the liver of broilers(P<0.05);4)The addition of ZEA increased(P<0.05)the ZEA residue in liver of broilers.In conclusion,ZEA would alter serum metabolites,induce hepatic oxidative damage,and increase the accumulations of ZEA in liver of broilers.Trial 2 was to investigate the effects of modified attapulgiteand vitamin E on the growth performance and digestive function of broiler chickens fed diets contaminated with ZEA.A total of 240 chickens were randomly allocated into 4 groups with 6 replicates of 10 birds each.The dietary treatments were as follows:1)the control group given the basal diet;2)the contaminated group given the basal diet supplemented with 2 mg ZEA/kg diet;3)the attapulgite group given the basal diet supplemented with 2 mg ZEA/kg diet and 1 kg modified attapulgite/t diet;4)the vitamin E group fed the basal diet supplemented with 2 mg ZEA/kg diet 100 mg vitamin E/kg diet.The results showed as follows:1)Compared with the control group,ZEA contamination reduced the average daily gain(ADG)and the average daily feed intake(ADFI)of broilers(P<0.05),whereas the modified attapulgite or vitamin E inclusion improved compromised ADG of broilers fed diets contaminated with ZEA(P<0.05);2)ZEA decreased serum TP and ALB concentrations of broilers(P<0.05),and the reduced TP and increased low density lipoprotein(LDL)content induced by ZEA inclusion were reversed by modified attapulgite and vitamin E(P<0.05);3)ZEA decreased the activities of pancreatic trypsin and anterior intestinal amylase and lipase whereas increased mucosal maltase activity in jejunum of broilers(P<0.05).Modified attapulgite increased the activities of pancreatic trypsin,and anterior intestinal amylase,lipase,and trypsin(P<0.05)of broilers fed the diet contaminated with ZEA(P<0.05).The inclusion of vitamin E increased activities of pancreatic trypsin and anterior intestinal amylase,whereas decreased the activity of mucosal maltase activity in jejunum of broilers(P<0.05).Broilers fed diet supplemented with modified attapulgite exhibited higher activities of pancreatic trypsin,anterior intestinal lipase,and jejunal maltase(P<0.05).4)ZEA reduced the apparent digestibility of organic matter(OM)of broilers(P<0.05).Modified attapulgite and vitamin E improved dry matter(DM),organic matter(OM),and ether extract(EE)utilization of the broilers given the ZEA diets(P<0.05).The results suggested that the modified attapulgite and vitamin E would partially reverse the negative effect on the growth performance and digestive function of broilers induced by ZEA contamination.Trial 3 was conducted to evaluate the effects of modified attapulgite and vitamin E on immunity,liver function,and ZEA residues in the tissues broilers fed ZEA contaminated diet.The experimental design was the same as that in Trial 2.The results showed that 1)ZEA decreased the spleen index of broilers,and the inclusion of modified attapulgite alleviated this effect in broilers fed the diet contaminated with ZEA(P<0.05).However,similar effect was not observed in broilers fed the diet supplemented with vitamin E(P>0.05);2)ZEA decreased the concentrations of IgA,IgM,IL-2,IL-5 and TNF-? in the serum broilers(P<0.05).In modified attapulgite group and vitamin E group,the concentrations of IgA,IgG,IgM,IL-2,IL-5 and TNF-a in the serum were increased(P<0.05)when compared with the negative control.Broilers fed the diet supplemented with modified attapulgite exhibited higher concentrations of IgA,IgG,IgM and and TNF-a in the serum broilers(P<0.05)compared with the vitamin E group(P<0.05);3)ZEA increased serum ALT activity whereas decreased hepatic T-SOD activity(P<0.05).Modified attapulgite and vitamin E significantly decreased serum ALT activity of broilers induced by ZEA inclusion(P<0.05).In contrast,modified attapulgite increased the activity of GSH-Px in the liver of broilers ingesting the ZEA contaminated diet(P<0.05);4)The supplementation of modified attapulgite significantly reduced the ZEA residue in the liver and breast muscle of broilers fed the ZEA contaminated diet(P<0.05),the similar effect was observed in breast muscle of broilers in the vitamin E group.The results suggested that the modified attapulgite clay and vitamin E can improve immunity,liver function,and reduce the accumulations of ZEA in the tissue of broilers.These results implied that ZEA(2 mg/kg)would increase the accumulations of ZEA in liver of broilers,induce hepatic oxidative damage,and alter serum metabolites.The supplementation of modified attapulgite and vitamin E would reduce the accumulations of ZEA in the tissue of broilers,and the modified attapulgite and vitamin E would partially reverse the negative effect on the growth performance,digestive function,immunity and liver function of broilers induced by ZEA contamination.