Effects of early cyclophosphamide treatment on lymphoid organs and its immune response in ducks.

Cyclophosphamide treatment of newly hatched White Pekin ducks significantly reduced the weight of their lymphoid organs and almost completely eliminated the formation of bursal lymphoid follicles at one week of age. There after the thymus and spleen of these ducks completely recovered in weight at 7 weeks of age. The bursa, however, retained its light weight and morphological defects, such as the absence of lymphoid follicles. The specific antibody producing-capability to Salmonella pullorum was also eliminated. The total dosage of cyclophosphamide was smaller than that employed in chickens, which makes effective chemical bursectomy in ducks possible.