Epidemiological Investigation And Prevention Of Duck Infectious Serositis In Yanzhou Region

Duck infectious serositis is a contagious disease caused by Riemerella anatipestifer(RA), and cause a primary violation of ducks, turkeys and other birds. The disease isalso known as Riemerella anatipestifer infection (RAI), duck plague syndrome, andso on. The incidence and mortality rates of the disease are very high. The disease hasbecome serious problem to the world duck industry and often caused huge economiclosses. Today, more serotypes of RA has been found. For lack of cross immunitybetween various serotypes of RA and easy to produce drug resistance, RAIs often leadto treatment failure and cause unnecessary economic losses.In this paper, the epidemiology and prevention of duck infectious serositis inYanzhou region were done.The results of investigation indicated in recent years duck infectious serositis inmeat duck farms of Yanzhou had occurred throughout the year, of which a higherincidence in winter and spring, the incidence of duck farms in26%to30%, lowerincidence in summer and autumn, the incidence of duck farms in12%to16%.The operation of pure culture, dye and observation, biochemical experiment, duplexPCR test, serotype classification drug sensitivity test of12isolates of RA fromYanzhou region were investigated. The results showed that the cultural characteristics,patterns of structure and basic biological characteristics of the12RA isolates werebasically consistent with the published information. The result of duplex PCR testindicted that two fragments (809bp and334bp) as they were expected were amplifiedfrom all the detected12RA strains. The serotype classification of the12clinicalisolates of RA showed that five of them were serotype10, three were serotype2, twowere serotype1, and two of undetermined serotype. This indicated that theepidemiological RA in Yanzhou region were10,2and1serotypes.The drug sensitivity test of12RA isolates from Yanzhou region were investigated.The result of drug sensitivity test showed that the bacteria were insusceptible for majorantibiotics and became multi-drug resistance, and only a few special antibiotics were susceptible to the bacteria.In this study, serotype10RA YZ01strain which was the representative strain of RAin Yanzhou region was used as antigen to produce inactivated vaccine. Theimmunogenicity of vaccine was studied after passing the sterile and security test. Theresults showed that the vaccine had a good immune response after ducklings wasinoculated subentaneously at the neck with0.3ml per duckling at the3-old-days. Thefield experiment identified that the vaccine was able to provide an ideal protectionagainst RAI in ducklings and the protective ratio reached more than94%...