Rapid Serological Pro¢ling by an Immunocomb-based Dot- enzyme-linked Immunosorbent Test forThree Major Poultry Diseases S. Manoharan*, M. Parthiban, T.G. Prabhakar, G. Ravikumar, A. Koteeswaran, N.D.J. Chandran and G. Rajavelu Vaccine Research Centre ^ Viral Vaccines, Centrefor Animal Health Studies,Tanuvas Madhavaram Milk Colony, Chennai 600 051, India *Correspondence:ulagaimano@yahoo.com Manoharan, S., Parthiban, M., Prabhakar,T.G., Ravikumar, G., Koteeswaran, A., Chandran, N.D.J. and Rajavelu, G., 2004. Rapid serological pro¢ling by an immunocomb-based dot-enzyme-linked immunosor- bent test for three major poultry diseases. Veterinary Research Communications, 28(4), 339^346 ABSTRACT An immunocomb-based dot-ELISA, employing specially designed apparatus, was used to measure the antibody status for the three major poultry diseases ^ Newcastle disease, infectious bursal disease and infectious bronchitis ^ in single test sera. Positive samples could be classi¢ed into strong, moderate and weak positives by comparison with the colour reaction given by known strong and weak positive serum controls. The simultaneous dot-immunobinding assay gave reproducible results and allowed consider- able savings on the cost of reagents compared to liquid ELISA. The antigen-coated immunocomb can be stored under refrigeration and the test can be performed rapidly under ¢eld conditions by trained personnel. Keywords: diagnosis, dot-enzyme linked immunosorbent assay, immunocomb, infectious bronchitis, infectious bursal disease, Newcastle disease Abbreviations: ELISA, enzyme linked immunosorbent assay; HRP, horseradish peroxidase; IB, infectious bronchitis; IBD, infectious bursal disease; IBDV, infectious bursal disease virus; IBV, infectious bronchitis virus; ND, Newcastle disease; NDV, Newcastle disease virus; OD, optical density; PBS, phosphate bu¡ered saline; TNE, Tris-HCl^sodium chloride^ethylenediaminetetraacetic acid INTRODUCTION The dot-enzyme-linked immunosorbent assay (dot-ELISA) is a solid-phase immunoas- say that can be used to detect either antigen or antibody (Hawkes et al ., 1982). Dot- ELISA is a simple, rapid and suitable procedure for screening a large number of samples at one time. It is highly e¤cient if a single test can be used to assess the antibody status for more than one disease entity at a time.The use of a single test not only allows economy of reagents but also increases the number of samples that can be conveniently tested. In the present study, an immunocomb-based dot-ELISA employ- ing specially designed apparatus was used to assess the antibody status for the major poultry diseases Newcastle disease (ND), infectious bursal disease (IBD) and infectious bronchitis (IB) in single test sera. VeterinaryResearchCommunications, 28 (2004) 339^346 # 2004 Kluwer Academic Publishers. Printed in the Netherlands 339