Utilization of Egg Quality Biomarkers and Probiotics for the Improvement of Eastern Oyster (Crassostrea virginica) Larviculture

Abstract

Shellfish aquaculture is a growing industry in the U.S., with the eastern oyster (Crassostrea virginica) being one of the most economically important cultured species. However, seed supply is a limitation to the expansion of oyster aquaculture, as hatcheries often experience high mortality rates. Thus, there is a need to understand egg quality characteristics and improve hatchery production methods. This thesis assessed egg quality biomarkers and the effects of probiotics on eastern oyster larviculture. Results indicate that saturated fatty acids, particularly palmitic acid, are elevated in good-quality eggs and may act as biomarkers for egg quality. Furthermore, supplementing Bacillus probiotics to rearing systems improved larval survival and significantly reduced relative abundances of Vibrio. Overall, this work identified fatty acid profiles of good-quality eggs to inform which diets may be effective for broodstock conditioning, as well as demonstrated the benefits of probiotics for hatchery-reared eastern oyster larvae.