Preparation and evaluation of an inactivated Infectious Bursal Disease [IBD] virus vaccines from recent Egyptian virus isolate adjuvated with Nigella sativa oil

Inactivated IBD virus vaccines were prepared from a recent Egyptian isolate and adjuvated with Nigella sativa. The first passages of propagated viruses in SPF-embryonated chicken eggs [ECE], Vero and chicken embryo fibroblast [CEF] cell cultures were inactivated with binary ethyleneimine [BEI] and supplemented with Nigella sativa oil, as adjuvant. The prepared vaccines proved to be highly immunogenic and elicited high titers of neutralizing antibodies [17-20 log2] at weekly interval till 7 months post-vaccination [PV] and high values of lymphocyte blastogenesis [0.598 versus control 0.06]. Besides, they were able to protect vaccinated chickens [100% protection] when challenged 21 days PV. The superior potential effect of these vaccines, when compared with imported one, may be due to the use of recent local IBDV isolate and Nigella sativa oil for its nonspecific immune stimulation effect. In addition, the keeping quality of prepared vaccines proved to be sterile, safe, stable and potent when preserved at 4C for 6 months [the end of the experiment] as they produced 100% and 80% protection after 3 and 6 months of preservation, respectively

Preparation and laboratory evaluation of live attenuated Infectious Bursal Disease [IBD] virus vaccine from recent Egyptian isolate propagated on chicken embryo fibroblast [CEF] cell culture.

Very virulent IBDV was propagated for 3 passages in SPF-ECE followed by 3 passages in young susceptible chicks then for 3 passages in SPF-ECE then for further 12 passages in SPF-ECE. The first passage of last propagation was further propagated for 3 passages on Vero cells and for 60 passages in CEF-cell culture. The passage 40 of propagated IBDV proved to be safe and highly immunogenic by virus neutralization test. It still elicited high neutralizing antibody titers [18 log2] for a stationary phase about 7 months [the end of the experiment] and high values of lymphocyte blastogenesis [0.560 versus control 0.03]. Vaccinated chicks well protected against challenge with highly virulent IBDV after 3 weeks post-vaccination [PV]. The prepared vaccine has superior potential immunogenic effect than commercial live mild and intermediate plus [hot] vaccines. The vaccine is effective even when preserved for 8 months [the end of experiment] at -20C