Study On The Experimental S.enteritidis Infection In Chickens

S.enteritidis is a non-host-specific pathogenic bacterium.It is an important human food-borne pathogens and caused animal disea.The main way to infect S.enteritidis through poultry.In recent years,with improvement in breeding industry,S.enteritidis infections are becoming more serious, and many cases of septic or cellulose showed exudative inflammation.To the broiler industry has resulted in serious economic losses,but also increase the risk of causing a public health problem. The broiler in Chongqing isolation and Identification from Salmonella enteritidis.The object of this article is study of bacterial infection in broiler in vivo distribution,induction of antibody production and serum biochemical indicators of the impact.It is lay the foundation for study of Salmonella enteritidis infection control measures and the establishment evaluation system of broiler Salmonella enteritidis contamination.1.The virulence of S.enteritidis for chickensInfected 12-day-old Sanhuang broiler through two ways:oral application inoculation,muscle of thorax inoculation with five different dosages.The median lethal dose of oral application inoculation is8.51×10~9 CFU.The median lethal dose of muscle of thorax inoculation is 8.52×10~8 CFU.2.The vivo distribution of S.enteritidis infection in chickensAfter infecting chickens with S S.enteritidis by muscle of thorax inoculation It is could be separated froln heart-blood and liver at 6 hours after inoculation.12 hours later,the bacterium could be separated from spleen,liver,lung,kidney and heart-blood.The bacteria could be isolated from brain at 24 hours after inoculation.3.The changes of pathologic histology with infected chickensSome chickens behaved obvious clinical symptom.Dissect the dead chickens,there was thicken epicardium and many exudations on heart,cardiac muscle fibers swelling,some showed severe granular degeneration and break.liver bleeding,Cerebrum telangiectasia and hyperemia, blood capillary swollen.Hepatic cell showed serious granular degeneration Spleen central artery vascular endothelial cell swelling,vessel wall structural disorder,acinus lienalis showed small amounts of acidophil leukocyte and more akaryocyte.4.The impact of serum biochemical indicators in infected chickensSalmonella enteritidis strain was used to infect 20 days age Sanhuang chiekens.Blood samples were collected from jugular vein at 12h,24h,48h,72h,96h,120h,144h,168h after infeetion.then analyze data use the Blood automatic biochemical analyzer.The results showed that AST activities were obviously higher than coutrol group(P<0.05) and ALB activities were obviously lower than coutrol group(P<0.05),ALT,LDH-L,GLO activities were increased significantly.TC,ALP activities were decreased significantly.Whole pathological proeess,the content of TP was almost constant.5.The growth and decline of antibody with chickensThe antibody of plate agglutination and agar diffusion are negative at 7 days.At 14days the antibody are masculine.The masculine antibody of plate agglutination until 42days.AGP antibody levels is concerned with the infection severity.35days later,antibody titer reach the peak value and went down.