The secretory immunological system of the fowl. VI. The effect of chemical bursectomy on immunoglobulin concentration in tears.

The effect of chemical bursectomy (3-5 mg testosterone cypionate injected at 12 days in ovo followed by 4-0 mg cyclophosphamide intraperitoneally at days 1 and 2 post-hatching) on concentration of immunoglobulins in tears and serum of chickens was investigated. Tears and serum samples were collected from bursectomized and normal control birds between days 26 and 120 post-hatching and were assayed for IgA, 7SIg and IgM concentrations using double gel-diffusion and radial immunodiffusion. No immunoglobulins other than passively acquired 7SIg were detected in the sera or tears of 23 out of 30 bursectomized birds throughout the time period. Sera were also assayed for natural agglutinins; normal birds had titres for rabbit erythrocytes which gradually increased from a mean of 1:24 at day 26 to 1:280 at day 120, while bursectomized chickens had titres of less than 1:8 throughout the experimental period. It was concluded that chemical bursectomy effectively abolished the secretory immunoglobulins normally present in tears as well as serum immunoglobulins.