Pakistan Veterinary Journal (Oct 2007)
PREPARATION AND EVALUATION OF VITAMIN E ADJUVANTED OIL EMULSIFIED INFECTIOUS BRONCHITIS EXPERIMENTAL VACCINE
Abstract
The present study was conducted to prepare oil emulsified (OE) infectious bronchitis (IB) experimental vaccines. The vaccines were prepared using the vaccinal strain H-120 Infectious Bonchitis virus (IBV). The virus was cultivated in 9-day old embryonated eggs via allantoic cavity route. Allantoic-amniotic fluid (AAF) was collected and inactivated with formalin @ 0.12%. Water in oil emulsion was prepared by adding one part of AAF to four parts of mineral oil containing water phase (Tween 80) and oil phase (Span 80) surfactants. Hydrophile lypohile balance (HLB) of the emulsion was maintained at 7.0. Two oil emulsified experimental vaccines were prepared. Vaccine-I was prepared without vitamin E and Vaccine-II with vitamin E (300 mg/ml). A total of 120 day-old broiler breeder chickens were divided into 4 groups, A, B, C, and D, each having 30 birds. At the age of 21 days, experimental Vaccine-I, experimental vaccine-II and commercial IB killed (H-120) vaccine were inoculated @ 0.5 ml in the birds of groups A, B and C, respectively. Group D was maintained as nonvaccinated control. Efficacy of the vaccines was evaluated on the basis of humoral immune response (haemagglutination inhibition antibody titres) against IB in the four groups. The seven weeks cumulative mean antibody titres (CMT) of each group were calculated. The highest CMT was observed in group B (130), followed by group C (69), group A (58) and group D (17). Statistical analysis showed that haemagglutination inhibition (HI) antibody titres in group B (vaccine- II) were significantly higher than those of groups A, B and C (P< 0.05).