REGULARITIES AND IRREGULARITIES IN THE STRUCTURE OF THE SEMINIFEROUS EPITHELIUM IN THE DOMESTIC-FOWL (GALLUS-DOMESTICUS) .2. COORDINATION BETWEEN GERM-CELL ASSOCIATIONS
T. Tiba et al., REGULARITIES AND IRREGULARITIES IN THE STRUCTURE OF THE SEMINIFEROUS EPITHELIUM IN THE DOMESTIC-FOWL (GALLUS-DOMESTICUS) .2. COORDINATION BETWEEN GERM-CELL ASSOCIATIONS, ANAT HISTOL, 22(3), 1993, pp. 254-263
It was investigated in the domestic fowl, whether a mechanism for a sy
nchronous stan of the proliferation of the differentiating spermatogon
ia in a transversely cut seminiferous tubule (called the ''co-ordinati
on' between germ cell association) operates effectively in this specie
s. A trapezoid-shaped cellular association demarcated by two perpendic
ulars from the tubular lumen to the basement membrane was the unit of
observation (provisionally called a ''column'' Each column is composed
of a bundle of elongate spermatids and the neighbouring, various type
s of germ cells). The extent of closeness of the co-ordination was exa
mined in a total of 2,650 columns, based on the continuity of the sper
miogenic sptep-number of the youngest generation of spermatids within
adjacent columns. In no case did all columns in a tubular cross sectio
n show the same-step spermatids. In most cases (50.2 % of 2,650 column
s), the same number was kept in only 2 to 6 adjacent columns. The arra
ngement of different but consecutive numbers (e. g., 1-2-3 or 1-2-1) w
as observed in a total of 882 columns. The co-ordination mechanism, th
erefore, is considered to work, albeit incomplete, among a limited num
ber of adjacent columns in this species.