Ramesh, GeethaBasha, Sabiha HayathManohar, B. MuraliKulasekar, KKishore, P.V.S.TANUVAS2016-05-272016-05-272006http://krishikosh.egranth.ac.in/handle/1/66392A systematic investigation on the post-natal histological development and histochemistry of the testis and its duct system was undertaken. The thirty-two Madras Red rams utilized for this study were divided into four age groups viz; pre- weaning (birth to 3 months), pre-pubertal (4 to 6 months), pubertal (7 to 9 months) and post-pubertal (10 to 12 months), each of which consisted of eight animals. The testis was a compound coiled tubular gland. At birth, the sex cords were smaller in size and solid without lumen. Between six and seven months of age, a well-developed lumen was observed. The sex cords were lined with small and large cells at birth. Sertoli cells and spermatogonia appeared at five months of age. The primary spermatocytes first appeared at the age of six months. From the end of the eighth month and at the ninth month of age, the round and elongated spermatids and the spermatozoa made their appearance. The ram lambs had attained puberty and were suitable for breeding from this age onwards.At birth, the interstitial tissue was closely packed and appeared to be predominant. The undifferentiated mesenchymal cells started its transformation at four months of age and mature Leydig cells were first observed during the fifth month of age. As age advanced, the tubular growth became predominant and the inter- tubular area decreased. The three regions of the epididymis consisted of six segments and showed regional differences. At birth, the epithelium was simple but as age advanced it became pseudostratified. The non-glandular portion of the ductus deferens was pseudostratified columnar from birth. Its terminal portion enlarged into an ampulla. In the ampullary region, at birth, the epithelium showed the branched folds and the lumen was irregular. The testis and its duct system showed a weak to moderate activity for neutral and acid mucopolysaccharides, glycogen and lipids in its different components, up to the pre-pubertal period. The reaction for lipids was weak up to the pre-pubertal period. The reaction became mild in the pre-pubertal period and thereafter was mild to moderate up to the maturity. The activity for phosphatases and dehydrogenases was weak in the pre-weaning and pre-pubertal periods, but with the onset of puberty, the enzyme activities were better developed.enThesis