DOI: 10.36347/sjavs.2017.v04i04.003

Pages: 138-145

Vaccination experiment was conducted with thermostable Newcastle disease (ND) vaccine strain I2 (NDVI2) to investigate its efficacy as feed based vaccine in chickens using cracked treated maize (TMZ) cracked treated sorghum (TSG),treated maize coated with gum Arabic (TMZG),treated sorghum with gum Arabic (TSGG) and their offals: untreated maize offal (MO) and sorghum offal (SGO) as vehicles. Immune response to vaccination and resistance to challenge were assessed by the haemagglutination inhibition (HI) test. Following vaccination at three and six weeks of age, sera was collected and analysed to determine the antibody titre in the different groups. All vaccinated birds developed HI antibodies to Newcastle disease virus (NDV) ranging from 0.0 log2 to 8.7 log2. In all the groups, the mean HI antibody titre peaked two weeks after second vaccination but declined prior to challenge at nine weeks of age. The highest mean antibody titre of 7.39 ± 0.42 was recorded when the vaccine was administered through (TSGG). Seventy eight (78%) per cent mortality was observed after challenge with NDV Kudu 113 strain in birds vaccinated with NDVI2 through TMZ and TSGG. No protection was observed in the unvaccinated control group, SGO and TMZG groups. Protection rate in all the groups was low with the highest rate (14%) when the vaccine was administered in TMZ and TSGG. There was no significant difference (P˃0.05) between the NDV HI antibody titre in the different feed carriers and the offals while a significant difference (P˂0.05) was observed between all feed groups at five weeks of age. From the study it was concluded that the grains and their offals were not suitable vaccine carriers for NDVI2. Further research need to be conducted on different methods of processing maize, sorghum and other locally available grains to remove possible antiviral properties in them to make them suitable vaccine carriers for protection of village poultry against ND.