The pattern of reproduction in the mole-rat Heliophobius from Tanzania: do not refrain during the long rains!

Canadian Journal of Zoology, e-First Articles. The genus Heliophobius Peters, 1846 comprises at least six cryptic, topotypical species in the Heliophobius argenteocinereus Peters, 1846 species complex. The current study investigated the breeding patterns of a wild-caught population from Tanzania where the putative species Heliophobius argenteocinereus emini Noack, 1894 resides. Individuals were collected on a monthly basis for an entire calendar year. Assessment of f œtus presence, gonadal histology, reproductive-tract morphometrics in combination with gonadal steroid (plasma progesterone and œstradiol-17β in females and testosterone in males) measurements and field observations revealed that rainfall is important for the onset of breeding. The results furthe r confirmed that breeding is limited to a single, yearly reproductive event synchronised to the long rainfall pattern. The distinct breeding peak in July is associated with an elevation in gonadal mass, increase in concentrations of reproductive hormones, and presence of Graafian follicles and corpo ra lutea in the ovaries of females. These reproductive parameters coincided with the end of the long rainfall period, whereas presence of young in the maternal burrow system corresponded with the start of the short rainfall of East Africa. These findings confirm Heliophobius has a single breeding op portunity each year, and this species is therefore vulnerable to any changes that may impact their climatically attuned breed...
Source: Canadian Journal of Zoology - Category: Zoology Authors: Source Type: research