Immunodeficiency in the chicken. I. Disparity in suppression of antibody responses to various antigens following surgical bursectomy.

The extent of suppression of antibody response by bursectomy (Bx) was examined as a measure of the seeding sequence of different clones from the bursa to peripheral lymphoid tissues. Chickens were bursectomized surgically 1, 4 or 7 days after hatching and immunized later with four antigens: sheep red blood cells (SRBC); Bordetella pertussis (Bp); human serum albumin (HSA); influenza virus (IV). The kinetics of the antibody responses were delayed in bursectomized birds when compared with the control groups. The following order in the degree of immunosuppression was established: Bp greater than HSA greater than SRBC greater than IV. This is discussed in relation to the 'sequential maturation' theory of ontogenesis of immunocyte differentiation. The data also stress the limitation of non-specific markers for assessing partial immunodeficiency states.