| Abstract: | Concentration and distribution of the three immunoglobulins in the sera and tracheal washings of a chicken population was studied. The mean IgM, IgG and IgA concentrations in serum were 1.35, 5.09 and 0.31 mg/ml, respectively. The distribution of IgM and IgG in birds irrespective of age was almost normal whereas that of IgA was skewed. All the three immunoglobulins were present in tracheal washings but the level of IgM was barely detectable. The IgG was predominant in the tracheal washings but higher IgA : IgG ratio compared to that of serum indicated local IgA production in the chicken respiratory tract. |
