BASOPHILS OF PARS DISTALIS ADENOHYPOPHYSIS IN MADRAS RED SHEEP (Ovis aries) – HISTOLOGY WITH REFERENCE TO VARIOUS AGE GROUPS

Histophysiological study of pituitary gland was conducted on Madras red sheep to record the age related changes. The pars distalis adenohypophysis comprised of cells arranged in irregular cords, grouped as acidophils, basophils and chromophobes. The basophils were round, oval and irregularly polygonal cells with distinct cell boundaries observed as 4 variants. The type I basophils were angular or polygonal cells stained intensely with aniline blue both in Mallory’s triple stain and Mallory’s Azan technique. Type II basophils were oval, polygonal in shape packed with course granules and showed strong PAS reaction. Type III basophils were oval or round cells, purple to violet in acid fuchsin and aniline blue preparations. These were aldehyde fuchsin negative and showed a mild PAS reactivity as compared to type II basophils. Type IV basophils were irregularly oval to elongate in shape with their processes extended through the neighbouring cells, moderately PAS positive but strongly positive for lead Haematoxylin. The number of basophils ranged from 862 ± 52.98 cells/mm 2 in lactating animals upto 1428 ± 83.14 cells/mm 2 in pubertal animals. The increased basophils during pubertal age groups of sheep indicated that the activity of FSH and LH cell that contributed the hormones required for the estrous cycles.