The Effects Of Selenium-enriched Probiotics On Growth Performances,Oocysts Shedding And Intestinal Lesions Of Local Chinese Chickens Infected With Eimeria Tenella

This study is carried out to investigate the effects of selenium-enrichedprobiotic(SP)supplementation on growth performance,oocysts shedding and intestinal lesions of local Chinese chickens infected with Eimeria tenella.One-day-old 270 chickens are randomly assigned into five groups,each consisting of three replicates.Chickens in the negative and positive controls(NC,PC)received basal diets only(0.11 mg Se/kg),whereas the other groups are supplied basal diets with probiotics and designated as(P,0.11 mg Se/kg),sodium selenite(SS,0.41 mg Se/kg)and(SP,0.41mg Se/kg)groups.At 21 days of age,except the NC group,all other groups are infected by oral gavage with 1.5 × 104 sporulated E.tenella sporulated oocysts per chicken.Nine chickens from each group(three chickens each replicate)are randomly selected for serum,liver and caecal specimen collection.The results showed that supplementation of P,SS,and SP had significant increase weight gain and feed intake.In addition,these groups showed higher activities of serum superoxide dismutase(SOD)and glutathione peroxidase-1(GPxl),and glucose(GLU),total protein(TP)and alkaline phosphatase(ALP)compared to PC group,whereas feed conversion ratio(FCR),oocyst shedding,intestinal caecal lesions score,alanine(ALT)and aspartate aminotransferase(AST),and serum catalase(CAT)activity andmalondialdehyde(MDA)content remained lower.Moreover,P,SS,and SP groups have lower oocyst shedding and caecal lesion scores.Significant upregulation of the glutathione peroxidase-1(GPxl),glutathione peroxidase-4(GPx4),SelenoproteinW(SelW)and interferon gamma(IFN-y)mRNA expression are detected in the SP group,followed by SS group compared to the P group.Whereas mRNA expression downregulated in the PC group compared to NC,P,SS and SP groups.The NC and P there are no statistical significant difference in mRNA expression,except that IFN-y mRNA level upregulated in P group.In conclusion selenium-enriched probiotic supplementation add value to poultry producers by enhancing growth performance,antioxidant capacities,mRNA gene expression,and reduction of oocyts shedding and the intestinal caecal lesion score of chickens and provide to protection against Eiemria tenella infection.