Environmental and Genetical Effects on Reproduction

Bill Breed | David Taggart | Elisa Sparrow | Liberty Olds | Karleah Trengove
Harsha Wechalekar

PhD student, Elisa Sparrow, is investigating the potential effects of inbreeding on the quality of sperm production and fertility in three populations of Hairy-nosed Wombats on Yorke Peninsula and in the Murraylands of SA.

Our studies on the Australian hopping mouse, Notomys alexis, have recently found that suppression of female reproductive activity occurs at high population density (Trengove, Carthew and Breed unpub. obs). By contrast, males of this species continue to produce sperm regardless of whether females are, or are not, reproductively active (Bauer & Breed, 2008). PhD student, Harsha Wechalekar, is determining the effects of mild heat stress on quality of sperm production in house mice and hopping mice, whereas PhD student Liberty Olds is investigating the effects of vegetation composition and structure on breeding and population changes of small mammals in the Kimberley region of Western Australia.

Work in our group by a Thai PhD student, Nuttawat Thitipramote, on a rodent species in the rice fields in southern Thailand, Bandicota indica, has shown that reproduction can occur throughout the year but its extent during the dry season varies markedly from year to year and correlates with the amount of rain in the preceding wet season; furthermore the results of this study have suggested a markedly divergent breeding system and social organisation from that of other coexisting rodents (Thitipramote, Suwanjarat & Breed, 2009).