Abstract:

An inactivated vaccine was prepared from Newcastle disease virus LaSota strain and local isolates of egg drop syndrome (EDS) virus HE03 strain using aluminum hydroxide as adjuvant. A total of 40 SPF layers at the age of 16 weeks were inoculated and divided into two groups, A and B having 30 and 10 chicks, respectively. The chicks of group A were vaccinated with 0.5 mL aluminium hydroxide gel adsorbed ND-EDS vaccine. The chicks of group B were kept as unvaccinated control. The serum samples were collected at a 14-day interval till 6 weeks post vaccination. At the age of 22 weeks, group A was again divided into two groups A1 and A2; chicks of group A2 and group B were challenged with a virulent EDS virus HE03 strain. The results revealed that chicks of group A had HI antibody titer against ND virus ranging from 1∶128 to 1∶512 at different times titer against EDS virus ranging from 1∶128 to 1∶512 at different times of sample collection with a geometric mean titer 1∶134; highest antibody response against EDS virus appeared on 4th week post vaccination with 1∶111. Results also revealed that the vaccination protected the chicks against challenge with the virulent EDS virus and ND virus. Where there was a significant drop in egg production in unvaccinated challenged chicks group B, the egg quality was also deteriorated as miss-shapened, soft-shelled and shell-less eggs were laid in unvaccinated layers.

Key words: egg drop syndrome; Newcastle disease; aluminium hydroxide; hemagglutination inhibition; vaccine; adjuvant