Effects of dietary DHA and EPA on neurogenesis, growth, and survival of juvenile American lobster, Homarus americanus

Abstract

It is crucial to fully understand nutrition in the American lobster, Homarus americanus, given the large interest in hatchery rearing for enhancement. Dietary studies have demonstrated that gross brain development as well as American lobster health and survival is greatly influenced by diet, and in particular the amount and type of omega‐3 fatty acids present in it. We conducted an assessment of how two important fatty acids, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, influence alobster's neurogenesis, growth, and survival. To evaluate the specific effects of EPA and DHA, lobsters were fed experimental casein‐based diets that varied in the source of oil. The control diet had flax oil (no EPA or DHA), whereas experimental diets were rich in EPA, DHA, or an even mix of the EPA and DHA oils. Lobsters fed the diets containing DHA oil developed fewer brain cells than those lobsters not fed this oil. Lobsters fed DHA oil also had a slightly, but not statistically significant longer survival time compared with lobsters fed the other diets. The decreased neurogenesis in the DHA‐enriched diets points to the need to understand regulation of nerve cell formation in lobsters, and the functional implications of neurogenesis. Because of the large effects of diet on physiology and health, nutrition will play a critical role in further development of lobster enhancement and aquaculture projects.

Keywords:

• aquaculture
• brain
• docosahexaenoic acid
• eicosapentaenoic acid
• enhancement
• nutrition