Abstract
The humoral immune response of chicken vaccinated with fowl and pigeon pox virus vaccines was determined with the protective potentiality of the two vaccines in field condition of Bangladesh. Different aged Fayoumi chicks were subjected for the study. To assess the relationship with better immune response among experimental groups, the average percentage of 'take reaction' was examined and recorded to 97.77% in group A, 93.33% in group B and 100.0% in group C. The level of immune status induced by different vaccinated group was measured by passive hemagglutination (PHA) microplate test method. The mean PHA titer levels after primary vaccination were $33.06{\pm}14.13$ in group A, $32.0{\pm}14.81$ in group B, and $33.0{\pm}13.66$ in group C. Following booster vaccination, the mean PHA titer levels in prior of challenge were increased to $55.46{\pm}14.64$ in groups A and C, and $46.93{\pm}16.52$ in group B. The recorded PHA titer levels of each group at two weeks after challenge were significantly increased to $106.66{\pm}31.22$, $93.86{\pm}33.04$ and $110.93{\pm}29.29$, respectively. The PHA titer levels after vaccination and challenge were significantly increased compared to pre-vaccination titer levels (P<0.01). Although the PHA titer levels among three groups administrated different vaccine combinations in prior of challenge were significantly varied (P<0.01), it was observed that all of the vaccinated chicks were highly protected against challenge infection.
