Karunakaran, KThanappapilldi, MRaghavan, NTANUVAS2020-05-292020-05-291993http://krishikosh.egranth.ac.in/handle/1/5810146659TNV_CIMID_1993_16(3)241Sera samples of 400 apparently healthy broiler poultry from 23 commercial farms and 120 sera samples from commercial layer poultry [with specific lesions of infectious bursal disease (IBD) in the internal organs] were screened for the presence of IBD serotypes I, II and the variant strain by the agar gel immuno diffusion (AGID) test, employing standard antigens. Likewise the bursae, spleen and kidney specimen from 96 layer poultry with lesions suggestive of IBD were screened for the presence of IBD antigens employing standard antisera by the AGID test. The study revealed that antibodies to all three strains of IBD virus existed in 73.75% of sera from 400 broilers, while only serotype II antigen was detectable in tissues of the 96 layer birds that exhibited characteristic lesions of IBD. It was concluded that the serotype I vaccine did not protect the layer poultry against serotype II infection and the totally unvaccinated broiler poultry had suffered subclinical infection from all the three serotypes of IBD virus.enArticle