Histochemical Characterization Of Chicken Lymphoid-Tissues

Thirteen enzyme activities were studied histochemically in the chicken bursa of Fabricius, thymus and spleen. The bursal epithelium contained a high activity of succinate, lactate and glucose-6-phosphate dehydrogenases and of ATPase. Activities of these enzymes were markedly lower in the follicle-associated epithelium than in the other parts of the bursal epithelium. A high activity of α-esterase occurred in the follicle-associated part in contrast to the other parts of the epithelium. The histochemical differentiation of the follicle-associated epithelium started at the time of hatching and was completed within a week. ATPase positive cells were observed in the interfollicular space of the bursa a few days before and after the hatching. The nature of these cells remained unclear. In the thymus, a good activity of lactate and glucose-6-phosphate dehydrogenases was observed in the area between the cortex and medulla, possibly indicating presence of endocrine cells. In the spleen no specific location of enzyme activities was observed.