Morphological and histochemical characterization of the seminiferous epithelial and Leydig cells of the turkey

Authors

M. R. Bakst, USDAFollow
V. Akuffo, USDA
P. Trefil, BIOPHARM
J. P. Brillard, INRA

Document Type

Article

Date of this Version

2007

Comments

Published in Animal Reproduction Science, 97, (2007) 303–313. doi:10.1016/j.anireprosci.2006.02.009

Abstract

Unlike mammals, there is little fundamental information about spermatogenesis in birds. This study was undertaken to clarify the morphology, histochemistry, and lectin affinity of the seminiferous epithelial cells and Leydig cells in pre-pubertal (8- to 15-week old) and adult (40- to 44-week old) domestic turkeys. In adult turkeys, three types of spermatogonia were defined based on their chromatin distribution and nuclear morphology: the dark type A(A_d); the pale type A(A_p); and the type B. The A_d is the least numerous and least conspicuous and consequently difficult to locate. Based on its spatial distribution and overall morphology, type A_d spermatogonia were postulated to be the spermatogonia stem cells in the turkey. Antibodies to c-kit were localized to spermatogonia in the pre-pubertal and to a lesser extent in adult males. Peanut agglutinin (PNA) was specific for spermatocytes in the pre-pubertal males and spermatogonia and early spermatocytes in adult males. Wheat-germ agglutinin (WGA) highlighted Sertoli cells in both age groups. Bandeiraea simplicifolia I, soybean agglutinin, and winged-pea agglutinin staining were limited to the wall of the seminiferous tubule and some extra-tubular cell types. Concanavalin A staining was diffuse and not cellspecific and, therefore, could not be used to selectively identify a particular cell type. It was concluded that WGA and PNA could aid in identifying specific cell types in the seminiferous epithelium of testis from prepubertal and mature turkeys. Only Leydig cells were alkaline phosphatase reactive in the mature turkey testes. The information from this study is being used to adapt techniques for the isolation and partial purification developed for mammalian spermatogonia to avian spermatogonia and other specific cell types in the testes.