Effects of moderately high temperature on the testis of the marbled newt, Triturus marmoratus

Abstract

AbstractIn order to investigate the effects of a moderately high temperature on testicular function in urodele amphibians, marbled newts (Triturus marmoratus) wcrc collected from thc field and killed at the end of each period of their spermategenetic cyle; these were: germ cell proliferation up to round spermatids (June), spermiogenesis (September), and the early (December) and late (March) periods of testicular quiescence. The testes of these animals were studied by light microscopy and compared with those of newts which were killed at the same dates and had been exposed previously to moderately high temperatures (30°C) for 1 or 3 months. The results of quantitative studies indicatc that: (1) exposure to high temperatures (for 3 months but not for 1 month) induces germ cell development up to round spermatids during the early phase of testicular quiescence; (2) this temperature has no effect in the period of germ cell proliferation up to round spermatids; and (3) high temperatures inhibit (exposure for 3 months) or decrease (exposure for I month) spermiogenesis during the spermiogenesis period.