Isolation, Characterization and Standardization of New Infectious Bursal Disease Virus for Development of a Live Vaccine

Abstract

Background and Aims: Infectious bursal disease (IBD) is an acute contagious viral disease of birds worldwide. The causative virus induces a persistent immune suppression following destroy B lymphocytes precursors in bursal lymphoid follicles. Vaccination is the main strategy for prevention of the disease in commercial poultry industry. Materials and Methods:To produce a live vaccine against the disease, an new virus strain was isolated from the affected bursa of Fabricius. Diagnostic serological tests, histopathology and molecular examinations were done for pathotyping the isolate. Results:The results indicated that the virus is a new strain and named IBD07IR. In case of developing live IBD vaccine, the bacteriology, purity, titration, reversion to virulence, bursabody index, immunosupression and efficacy tests were performed on the candidate vaccine virus seed. The live vaccine was produced following propagation of the IBDV seed in SPF embryonated eggs. The proper dose of the vaccine was found by administration of SPF chicken groups. Afterward, the laboratory trial was scaled and the clinical trials were done three times with different administration routs. Conclusion: According to serological assays and challenge, the developed live IBD vaccine induces an adequate immunity in both SPF and commercial chickens and had no adverse effects.

A review of the Infectious Bursal Disease (IBD) in Iran

“…After preparing the vaccine, the clinical evaluation was performed on 60 SPF chickens in two groups via ocular and drinking water routes. The results showed the vaccine efficacy and the induction of sufficient immunity (29).…”

“…Developing of new vaccines using newly discovered strains is one of the procedures to develop new vaccines. In 2013, Ebrahimi et al isolated and identified a new IBDV strain named IBD07IR for vaccine development (29). The IBD07IR strain was identified as one of the vvIBDV strains using different serological tests and restriction fragment length polymorphism (RFLP) (29).…”

“…In 2013, Ebrahimi et al isolated and identified a new IBDV strain named IBD07IR for vaccine development (29). The IBD07IR strain was identified as one of the vvIBDV strains using different serological tests and restriction fragment length polymorphism (RFLP) (29). Then, this strain was attenuated through passaging in SPF chicks at four-day intervals.…”

Evaluation of the Effects of Chitosan on Immune Responses due to Infectious Bursal Disease Virus (IBDV) Vaccine in Chicken

“…The IBDV antigen was prepared by injection of IBD07IR intermediate strain [14] into chorio-allantoic membrane of 9-11-day-old SPF chicken embryos (obtained from Razi Institute, Karaj, Iran). After 5 days incubation at 37°C, the amnioallantoic fluid and infective embryo were harvested, grinded, and clarified by centrifugation at 5000 rpm for 30 min at 4°C.…”