Determination of immune response of imported Newcastle disease virus vaccines in broiler chickens
Keywords:Immune response, Newcastle disease, ND vaccines, broiler chickens
A study was undertaken to determine the immune response of eight different imported live NDV vaccines in broiler chickens in the Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh during the period from July to December 2008. A total of 55 broiler chickens (Ross breed) were divided into eleven groups such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 of which group 1, 3, 5, 7 and 9 were vaccinated primarily with NobilisÂ® MA5+Clone30, AviproÂ® ND-IB HB1, CevacÂ® BIL, Newcastle-Bronchitis Vaccine FortdodgeÂ® and AviproÂ® ND LaSota vaccine respectively at day 5 of age and secondarily with NobilisÂ® ND Clone 30, AviproÂ® ND LaSota, CevacÂ® New L, Newcastle Disease vaccine FortdodgeÂ® and AviproÂ® ND LaSota vaccine respectively at day 21 of age by single eye instillation and 2, 4, 6, 8 and 10 were vaccinated with the same vaccines respectively by double eye instillation following the same schedule. Group 11 was kept as unvaccinated control. Sera samples were collected after 10 days of each vaccination and at day 5, 15, 20, 31 of age from nonvaccinated control and subjected to HI test for the determination of antibody titres. It was observed that after primary vaccination the geometric mean (GM) of HI titres of double eye vaccinated groups differed significantly (P<0.01). Overall analysis of GM of HI titres of double eye vaccinated groups revealed that there were significant increases (P<0.01) in HI titres in groups 8 (301.07Â±70.10) and 10 (284.24Â±85.86) compared to other groups. It was observed that secondary vaccination produced higher immune response compared to primary vaccination in case of all the vaccinated groups and double eye vaccination produced higher immune response compared to single eye vaccination in case of all the vaccinated groups. Maternal antibody was high (256.00Â±140.21) at day 5 of age and persisted to a minimal level (5.27Â±2.19) until the age of day 20 and almost disappears (â¤4Â±0) at day 31 of age. From the present research it may be concluded that LaSota strain produced higher immune response than Clone 30 and B1 strain and FortdodgeÂ® and AviproÂ® vaccine produced higher immune response than all other vaccines used in this study.
Key words: Immune response, Newcastle disease, ND vaccines, broiler chickens
Bangl. J. Vet. Med. (2008). 6 (2): 139-144