Changes in ovarian follicle composition with plasma levels of snakes during estrus

Abstract

The first stage of follicle development was due chiefly to hydration; during the second (deutoplasmic) stage 60 mg of solid were taken up with each 100 mg increase in follicle weight. Plasma calcium and protein P rose near end of hydration stage, remained elevated during deutoplasmic stage, reached extreme levels (max. Ca = 90 mm/l.; protein P = 86 mm/l.) near ovulation, and generally fell to anestrous levels while eggs were in early cleavage. Calcium increased in proportion to protein bound P of both plasma and follicles. During deutoplasmic stage a phospho-lipoprotein, of similar gross composition to yolk protein, appeared in plasma. Liver weight increased during hydration stage, remained elevated throughout deutoplasmic stage and decreased near ovulation. Fat body weight increased with onset of estrus, reached maximum during hydration stage and progressively decreased during deutoplasmic stage. Plasma and liver changes characteristic of estrus were reproduced in fasted male snakes with estradiol injections.