Scanning electron microscopic study of the male genital tract during its highest and lowest activities in the seasonal reproductive cycle of the soft-shelled turtle.

Abstract

The objective of the present investigation was to study by scanning electron microscopy the epithelial surface structures of different segments of the male genital tract (ductuli efferentes, proximal and distal epididymes, and vas deferens) during highest (July) and lowest (January) activity in the annual reproductive cycle of the soft-shelled turtle. The study has revealed that there are distinct regional differences in the male genital tract. The ductuli efferentes have three types of cells, long-ciliated, short-ciliated, and microvilli-bordered cells. The proximal epididymis has two types of cells, microvilli-bordered cells and smooth-surfaced cells; the distal epididymis has only tall, smooth-surfaced cells. The vas deferens contains both smooth-surfaced and microvilli-bordered cells. Cells of the genital tract in July show several differences from comparable cells in January: Ciliated cells of the ductuli efferentes have longer cilia, cells of the proximal epididymis have microvilli distended by secretory materials, and cell apices in the distal epididymis are surmounted by an abundance of huge secretory blebs. There is no discernible change in the vas deferens. The findings suggest that all segments of the male genital tract, except the vas deferens, become active in July and have regressed by January in the annual sexual cycle.