Tillmann Benfey (Department of Biology, UNB Fredericton)
Triploid populations of fish are easily produced through simple temperature or hydrostatic pressure treatment applied to eggs shortly after fertilization. This does not affect subsequent mitotic cell division, but such triploids are sterile due to meiotic dysfunction and, as a result, they can be used in aquaculture to ensure that fish which escape from farms cannot breed in the wild. While there is clear benefit to this, triploids are rarely used in commercial aquaculture because of repeatedly demonstrated reduced performance compared to conventional diploids. A significant body of literature points to ploidy-related impacts on nutrient utilization and environmental tolerances, in both cases likely due to profound effects of triploidy on cell size and number. Much of my past and current research program has focused on determining how triploidy affects temperature and hypoxia tolerance in fish, with the twin goals of advancing basic knowledge in physiology and then using this to refine rearing protocols for aquaculture. My seminar will provide a general introduction to triploidy in fish and summarize student-led research in my lab using both zebrafish and brook trout as models to study the impacts of triploidy on erythropoiesis, aerobic capacity, and environmental tolerances.