Locally available grains as carriers of Newcastle Disease V4 vaccine in Zimbabwe: An experimental trial

Abstract

Laboratory trials were conducted to evaluate the potential of locally available grains as vehicles for the administration of the Australian Heat Resistant V4 vaccine. Feeds tested included millet, sunflower, crushed maize, rapoko, barley, sorghum and rice. One hundred and fifty four indigenous chickens were randomly divided into treatment groups according to the number of feeds tested. Each trial group was vaccinated six times orally at monthly intervals. Haemagglutination inhibition test titres and challenge experiment were used to monitor effectiveness of the vaccination strategy. Rapoko performed as the best vaccine carrier, giving protection levels of up to 80% after the sixth vaccination. The other grains tested gave protection levels ranging from 0% to 67% after the sixth vaccination. These results demonstrate that locally available grains should not be used as V4 vaccine carriers for effective control of Newcastle disease in the field as it takes too long to reach protection levels.


(Zimbabwe Veterinary Journal, 2000, 31(2&3): 45-56)