Study On The Prevention And Control Of Chicken Colibacillosis In Zaozhuang Area

With the development of the chicken industry, colibacillosis has a graually harmful effect on the chicken industry in Zaozhuang area, which results in great damage in economics.The immunity and prevention of vaccine will fail to achieve the expected effects because of the wide existence of colibacillosis with complexed coil stertypes, which leads to clinically drug abuse strengthening the drug sensitivity of bacteria and maintaining the left drug which is bad for our health. This paper aims to study the prevention and control of colibacillosis in Zaozhuang and probes the causes and rules of coliacillosis, distrubition of coil stertypes and drug resistence state and works towards a technical and sound measures by tests on home-made vaccine and compand agent. The tests compose of three parts:1. Epidemiology SurveyThe test concentrates on chicken colibacillosis by veterinary epedemiology method, which shows that the inducing factors of the diseases is very complicated with disease rate of 31.6% and death rate of 14.43%accounting for 42% of the total diseases.The chickens of differen day ages all have the chance to get disease, among which the age of 15-35 days are dominate disease age accounting for 50%-60%, the age of 35-40 and 7-15 days are sencondary and the age of less than 7 days and more than 40 days start less diseases. Moreover, egg layers tends to start disease in times of before and after producing eggs as well as the summit period of laying eggs and less in incubation times.Colibacillosis can be seen in every season with cold winter from Decomber to the next January and high temparature and rainy, damp season from July to Auguse as well as the temparature-changing season from April to May accounting for 84% of the total diseases. 2. Separation and Identification of Pathogenic and Drug Sensitive TestThe test extracts 22 fatal colibacillosis out of 27 types of naturally chicken colibacillosis data by regular separation method in five districts and one city in Zaozhuang with separation rate of 81.49%. Among all the 20 coli strains, 9 of O₇₈serotype, 4 O₃₅ serotype, 2 O88 serotype, 1 O₂ serotype, 1 O₁₈ serotype, 1 O₅ serotype , 1 O₁₅ serotype and 1O₁₁₁ serotype. Furthermore, O78, O35 and O88 serotypes are dominate accounting for 75% of typing strains, among which, O₇₈ serotype is junior accounting for 45%. The drug sensitive test of bacteria shows that separated strains have taken up different drug resistence, 86.36% to amikacin, cephradine and cefotaxime, 81.82% to cefazolin , 77.27% to florfenicol. But there do exists certain differences in drug resistence and sensitive strains in Zaozhuang.3. Study on Colibacillosis Prevention and Control in ZaozhuangThree fatal serotypes (O₇₈,O₃₅,O₈₈) choosing from the 8 separated coli serotypes, are made into oil emulsion inactivated vaccine with protection rate of 98% by field immunity test. Chosing amikacin, ribavirin, dexamethasone and VC as compound agent, the protection rate changes to 97.5% by control test to infected chicken, which is more effective comparing to amikacin (the protection rate 90.0%). In addition, the compound agent will achieve the maximum clinical effect by injection method. The result provides scentific and technical support for prevention and control of chicken colibacillosis.