Pakistan Journal of Biological Sciences1028-88801812-5735Asian Network for Scientific Information10.3923/pjbs.2003.998.1004AdhikaryG. N.QuasemM. A.DasS. K.112003611The present study was conducted in the Department of Anatomy and Histology with an aim to observe the histological architecture of thyroid gland at prepubertal, pubertal and castrated Black Bengal goat with Hematoxylin and Eosin stain. The thyroid gland was covered by a three-layered capsule, an outer, the middle and an inner layer. The connective tissue capsule was rich in blood vessels, some times accompanied with lymphocytic infiltration also some fibroblasts. From the capsule, connective tissue septa penetrated the gland parenchyma forming indistinct lobe and lobules of the gland. The thyroid gland was consisted of numerous follicles with interfollicular stroma. The follicle consisted of follicular epithelium and intrafollicular substances. Usually, small sizes follicle were near the capsule and active, whereas, large sizes follicle were towards the center of the gland. The thyroid follicles were lined by cuboidal epithelium in prepubertal Black Bengal goats, cuboidal to columnar in pubertal group. Follicular epithelium becomes squamous or flattened in castrated group. The thyroid follicle contained amber-colored homogenous, solid, lightly eosinophilic colloid material. In the active follicle the colloid was thinner and less in amount, whereas, in inactive follicle it was thicker and more quantity. The colloid materials mostly cracked at castrated group but cracked colloidal materials were found in few large follicles or absent in prepubertal and pubertal group of Black Bengal goats. Parafollicular cells or interfollicular cells were arranged singly or grouped within the basal lamina or interfollicular space. The parafollicular cells were significantly decreased in the adult castrated Black Bengal goats than prepubertal and pubertal group. The inetrfollicular spaces were significantly decreased in castrated Black Bengal goats when compared to prepubertal and pubertal group. Thus it can be assumed that histoarchitectures of the thyroid gland of Black Bengal goat changed at different stages with their activity.]]>Agrawal, K.P. and N.K. Bhattacharyya,198151328332Baishya, G., S. Ahmed and M. Bhattacharyya,198656667669Das, L.N., D.B. Misra and G. Biswal,196542824830Dellmann, H.D. and J.A. Eurell,19985th Edn.,pp: 294-295pp: 294-295Ham, A.W. and D.H. Carmack,19798th Edn.,pp: 801-802pp: 801-802Mathur, M.L.,1994Bos bubalis).]]>1994Mathur, M.L.,1971Bos bubalis).]]>32363366Pearse, A.G.E.,1967164478487Ronald, L.C. and S.L. Thomas,19613rd Edn.,pp: 461-465pp: 461-465Roy, K.S. and R.P. Saigal,1987572626Roy, K.S., R.P. Saigal, B.S. Nanda and S.K. Nagpal,19781438695Roy, M.K.,19711971Sanap, S.M., R.R. Mugale, N.S. Bhosale and C.S. Mamde,199875813816Roy, K.S. and R.C.P. Yadava,1975Bubalus bubalis).]]>1975