Study On Drug Resistance Of E. Coli From Chicken In Gaomi County

Chicken's colibacillosis is a focus or systemic infectious disease,which is caused by E.coli with complicated antigens,multiple serotype and various clinical symptom.Colibacillosis often happens together with various viral or bacterial diseases and has been spread every where in the world.The more and more serious economic losses to poultry industry have been existed.As antibacterial is widely used,the problem of drug-resistance and residual of drug in poultry products increased seriously.It brings serious harm to continuous development of poultry industry and human health.Study on drug-resistance of E.coli has theoretical and practical significance.Three Parts have been ineluded in this experiment:1.The operation of pure culture,dye and observation,AST(antimicrobial susceptibility test) and biochemical experiment of 46 isolates of E.coli from Gaomi county were investigated.The results showed that the cultural characteristics,patterns of structure and basic biological characteristics are basically consistent with the published information.But the result of AST showed that the bacteria are insusceptible for major antibiotics and become multi-drug resistant seriousil,only a few special antibiotics are susceptible to the bacteria.2.The minimal inhibitory concentration(MIC) of benzylpenicillin sodium against 46 isolates of E.coli were detected.The results showed that only 7 isolates(15.22%) can be inhibited by 20IU/ml of benzylpenicillin sodium,and the MIC of 60.87%(28/46) isolates were between 100IU/ml to 200IU/ml,specifically,the MIC of No.12 isolate was about 230IU/ml.3.TEM1 gene codingβ-lactamases were detected by polymerase chain reaction(PCR) in the 46 isolates of E.coli.The results indicated TEM1 gene could were from the 65.22%(30/46) isolates,but not all the ampicillin-resistance isolates were positive.