Histoarchitectural and histochemical studies during development of thymus in chick embryo

Abstract

This study was conducted to elucidate histoarchitectural and histochemical changes in chick thymus during development of embryo. In 6, 11 and 14 day-old embryos thymus was made up of epithelial cords.At 16th day of incubation it was faintly divided into lobules which at 18 day were well demarcated by connective tissue septae. At 18th day medulla was light staining with few Hassell's corpuscles. Demarcation between cortex and medulla became more distinct at 2lst day of incubation. Acid phosphatase activity was mild in 18-day 21-day-old embryos scattered in thymic follicles. Intense cholinesterase activity was observed in 18-day-old embryo uniformly scattered in thymic follicles. Very week activity of ATPase was found in periphery of thymic lobules in 21-day-old embryo. No activity of glucose-6-phosphatase. lipase,5 nucleotidasea and alkaline phosphatase was found. Simmilarily lipids, mucopolysaccharides and PAS positive material was not found at any development stage.