Efficacy of Prepared Oil Inactivated Pigeon Paramyxo Vaccine

Abstract

Control of pigeon paramyxo virus infection relays on the production of a vaccine that is able to protect the birds from the lethal virulent infection as well as reducing shedding level to prevent virus circulation in the environment. In the current study inactivated vaccine was prepared from the recent field isolate (PPMV-1 YA/14) which is extensively characterized and identified. The vaccine was prepared in two formulas. The aluminum hydroxide gel (given S/C and I/M) and the oil adjuvanted formula. Evaluation of the 2 formulas revealed that the gel-based formula gave a higher antibody titer than the oil-based preparation during the course of the vaccination period and after challenge. The cellular immune response was also evaluated by the QRT-PCR analysis of the IFN-γ transcripts and it was found that the oil-based formula gave a high fold change than the gel-based formula although it was not reflected in decreasing the shedding level. Studying the shedding level by the EID50 or QRT-PCR of the cloacal swaps after challenge revealed that the gel-based formula administrated S/C gave lesser degree of shedding than the oil-based formula. In conclusion the gel-based formula of the vaccine prepared from the recent characterized PPMV-1 YA/14 isolate could protect pigeon from lethal infection with the virulent virus and could reduce but not eliminate the shedding level.