In many species, females can control fertilisation after mating via several different mechanisms - a process called cryptic female choice (CFC).
It is generally unknown how this might happen in external fertilisers such as fish, where eggs and sperm are shed simultaneously into the surrounding water.
Professor Neil Gemmell and his team from the Department of Anatomy & Structural Biology at the University of Otago recently demonstrated that Chinook salmon ovarian fluid (a viscous substance released with eggs during spawning) can alter male sperm function, with the result that females have some control over male reproductive success.
The rationale behind this control is unknown, but it may allow combinations of genes that produce better quality offspring.
Professor Gemmell and his team will use sperm analysis, competitive fertilisation trials, and genetic markers to determine if there is a genetic basis for the observed cryptic female choice.
Their study will provide insight into the various causes of CFC, a process that has so far proven notoriously difficult to investigate.
This will build research capacity in an area that has important implications for fertility enhancement and control in aquaculture, agriculture, conservation and human health.
Total Funding: $870,000 over 3 years
Principal researcher: Professor Neil Gemmell, Centre for Reproduction and Genomics, Department of Anatomy and Structural Biology, University of Otago