|Institution:||University of Windsor|
|Keywords:||Egg Quality; Egg size; Genetic effects; Lipids; Maternal Effects; Salmon|
|Full text PDF:||http://scholar.uwindsor.ca/etd/5249
Maternal effects have received considerable attention within the literature, however our knowledge on environmental and genetic maternal effects on egg quality in fish still remains limited. I examined both environmental and genetic maternal effects on egg quality traits in hatchery, wild and farmed Chinook salmon (Oncorhynchus tshawytscha). I found that environmental differences during early life altered certain aspects of the reproductive biology in hatchery- and wild- salmon, namely gonad and egg development, while other important components of egg quality, fatty acid profile, were not affected. By using quantitative genetic models and breeding designs, I determined that egg size was strongly influenced by maternal genetic effects and was heritable across families. Together, these results suggest that differences in early- rearing environment and associated selection pressures during early life can alter critical life history traits in adults, as a result of both environmental and genetic maternal effects.