Historical study of the testes in the fruit-bat. Ediolon helvum (KERR)

Abstract

Bats of the species Ediolon helvum have been used for research and teaching purposes in East African Universities for more than twenty years. In all this time, only one birth has been recorded in the laboratory. No attempt, has so far, been made to understand why these animals fail to reproduce in confinement, while they do so regularly in the field from where they are collected. A histological study of the testes of both domesticated and wild bats reveals highly spermatogenic seminiferous tubules in March. Spermatogenesis appears to decline by July and seems to cease by August. However, spermatogenesis appears to resume by October and is clearly apparent in November. Large numbers of spermatozoa are present in the epididymis in July and these are still persistent in October, though in reduced numbers. There are no obvious morphological differences between the testes and epididymis of the wild bats when compared with the domesticated bats.