Journal of Aquaculture Research & Development

Genetic selection and nutritional effects on physiological, genomic, and intestinal microbial responses and interactions

International Conference on Aquaculture & Fisheries

July 20-22, 2015 Brisbane, Australia

Ken Overturf

Posters-Accepted Abstracts: J Aquac Res Development

Abstract:

Complete replacement of fishmeal in feeds has proven difficult for a number of aquaculture species. In carnivorous fish plant proteins often cause reduced growth and negatively affect gut health. Also, replacement of fish oil generally leads to a severe reduction for longchain omega-3 fatty acids in tissues. Little is known about strain differences regarding effects of plant based diets in fish and the potential for selection for improved gut health, EPA and DHA synthesis and deposition, disease resistance and performance. Our laboratory has been selecting fish for the ability to efficiently grow and utilize in all plant protein diet that includes relatively high levels of soybean meal and soy protein concentrate. After several generations of selection we find that our selected fish not only grow faster than non-selected fish on the plant-based feed but do not develop intestinal enteritis as do non-selected fish. Furthermore, we have determined that variation exists within trout stocks for the ability to biosynthesize and deposit EPA and DHA in muscle in fish reared on feed in which fish oil has been replaced with flax oil. We are now utilizing these fish as a model to determine the underlying biology behind these traits we have chosen to examine the physiological and genetic components by evaluating data obtained from histological, transcriptomic, genomic, proteomic and microbial host interactions. In this presentation we will show responses and discuss the effect of diet and selection on animal physiology, metabolism, and gut microbiota and host responses.