REACTIONS OF CHICKEN BILIARY IMMUNOGLOBULIN-A WITH AVIAN MYCOPLASMAS

Chicken bile was examined for mycoplasma by culture and for antibody against mycoplasma by indirect immunoperoxidase assay (IIPA) detecting chicken either IgA or IgG and IgM, as well as by rapid plate agglutination (RPA), haemagglutination-inhibition (HI) and double immuno-diffusion (DID). Cultures indicated the presence of M. gallisepticum (Mg) and M. synoviae (Ms) in bile and their isolations were positively correlated with those from upper respiratory tract. In 45 chickens from five flocks examination of biliary samples with IIPA detected considerably higher rates of Mg and Ms antibodies than the same assay performed with sera especially those of IgA class of antibody. In chickens with a strong serological response to Mg, titres of specific agglutinins and HI antibody in biliary samples were significantly higher than those found in sera. Only biliary fractions containing Ig exhibited antibody activity.