ISSN 2736-1756
Advanced Journal of Microbiology Research Vol. 2012
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2012 International Scholars Journals
Full Length Research Paper
Immune response and protection of free range chickens vaccinated orally with feeding of newcastle disease vaccine-coated cassava granules
Echeonwu G. O. N1*, Iroegbu C. U2, Echeonwu B. C3, Ngene A4, Nwosuh C. I5, Joannis T. M6 and Ndako J1.
1Virology Department, Federal College of Veterinary and Medical Laboratory Technology, National Veterinary Research Institute, Vom, Plateau State, Nigeria.
2Department of Microbiology, University of Nigeria, Nsukka, Enugu State, Nigeria.
3Poultry Department, National Veterinary Research Institute, Vom, Plateau State, Nigeria.
4Department of Veterinary Medicine, University of Nigeria, Nsukka, Enugu State, Nigeria.
5Viral Vaccines Production Department, National Veterinary Research Institute, Vom, Plateau State, Nigeria.
6Viral Research Department, National Veterinary Research Institute, Vom, Plateau State, Nigeria.
Accepted 20 April, 2012
Abstract
Cassava granules coated with Newcastle disease virus (NDV) strain V4-UPM was used to vaccinate free-range chickens in their natural habitat. Immune response, vaccine virus excretion and the efficacy of the food vaccine were assessed by standard methods. Results show that out of 218 chickens given initial food vaccine in the four locations, 138 (63.3%) produced detectable HI antibody while 202 (92.7%) had titres < 3.0. However, only 16 (7.3%) attained log2 3.0 with GMT of 3.2. This was made up of Nchara- Akanu 7(12.7%), Vandekya 0(0.0%), Fadan Karshi 1(1.7%), and Turu 8(15.1%) with GMTs of 3.3, 2.9, 3.0, and 3.6 in that order. Following the administration of a booster dose of vaccine on 194 birds in the same flocks, 170(87.6%) sero-converted with 118(60.8%) attaining log2 3.0 and GMT of 9.7. Chickens attaining HI titres up to log2 3.0 from the locations were as follows, Nchara-Akanu 26(51.0%), Vandekya 22 (51.2%), Fadan Karshi 28(53.8%), and Turu 33(68.8%) with GMTs of 12.8, 7.5, 7.0, and 12.6 respectively. Vaccinated birds excreted infective vaccine virus. Out of 55 buyback chickens challenged, 15(27.3%) died while 40(72.7%) survived. Twenty two (22) out of 24 (91.7%) unvaccinated birds challenged died and only 2(8.3%) survived. It is therefore concluded that cassava granules could be good carrier for food-borne ND vaccine delivery to village chickens in Nigeria.
Key words: Cassava, V4-UPM virus, village chickens, Newcastle disease.