Study Of Epidemiology And Control Of IBD In Lixin County

For recent years, the prevalence of infectious bursal disease (IBD) is increasingly complex, and the frequent failure of immunization is of common occurrence. In order to make well IBD prevention and control work for Lixin County, we research the following three aspects of IBD and testing, to find out popular features in recent years, and its change in IBD, to lay the foundation for IBD effective control.(1) between2006-2009year, the prevalence and epidemiology of IBD in chickens in six key towns in Lixin County were investigated. The results showed that, the trend of IBD incidence in any season one year is coming, but still6-9months each year for the onset of the peak; incidence of extended day-old chicken:lesion was jelly-like edema with IBD and renal urate deposition as the main feature, there were both67.2%and73.11%;other lesions are atypical; pathogenesis of immuned chickens accounted for78.17%, accounting for16.98%of secondary disease in chickens; and host and the range of susceptible poultry expanded. Survey results suggested that the current need to seek new strategies IBD control and reduce the immune flocks of wild virus infection risk, and to strengthen comprehensive prevention and control measures in IBD.(2) Lixin County IBDV Isolation and identification. In this study, diseased collection, egg inoculation, animals, regression test, ELD50measurement techniques, RT-PCR technology, the typical occurrence of IBD in chickens suspected IBDV isolation and identification were successfully isolated, respectively named as BZ03, BZ05and BZ02three (super-) endemic virulent strains. The results suggest thatthe presence of (super-)virulent strain caused by the immune chickens may be one of the reasons the incidence, while the findings are helpful for further research on IBDV molecular epidemiology, molecular biology and effective immunization for the future lay basis.(3) study of vaccine develop by the isolated strains and its protective effect. The strains BZ03, BZ05and BZ02through10passages with chick embryo as virus were used for chicken embryo inoculation, while inoculation with chick embryo vaccine strains B87, with the harvested allantoic fluid of chick chorionic trial out of trivalent oil emulsion vaccine and the B87oil emulsion vaccine and immune effects were measured and compared. The results showed that the prepared oil emulsion inactivated trivalent vaccine immunity and single trivalent oil emulsion inactivated vaccine and live vaccine and immune effect of oil emulsion vaccine group B87is better than live vaccine immunization group, and by the local drug preparation of strains of the trivalent inactivated oil emulsion did not show resistance to different strains of the different; and by contrast. B87oil emulsion vaccine group and the live virus vaccine trials in the attack, attack protection against different strains were low, and showed some differences. In this study, on the one hand, to control IBD of Lixin County in the future, it provided the material foundation; at the same time the results also suggested that wild strains and vaccine strains of antigenic correlation among immuned chickens help to reduce the risk of wild virus infection.