|BUENTELLO, ALJANDRO - Archer Daniels Midland|
|BLOCK, STEPHANIE - Archer Daniels Midland|
Submitted to: World Aquaculture Society Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 12/8/2018
Publication Date: 2/22/2018
Citation: Burr, G.S., Peterson, B.C., Buentello, A., Block, S. 2018. Growth performance of Atlantic salmon (Salmo salar) smolts fed diets containing heterotrophic algal biomass as replacement of fish oil. World Aquaculture Society Meeting. 1.
Technical Abstract: Atlantic salmon (Salmo salar) is an important cultured carnivorous species that has increasing amounts of plant proteins and oils included in the diet. Both consumers and producers expect fillets to contain elevated levels of omega-3 fatty acids [docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)]. Due to the low levels of these nutrients in traditional plant ingredients compared to marine sources, supplementation of aquaculture diets with omega-3 rich ingredients is required. Microalgae has garnered attention as a potential ingredient to provide long chain omega-3 levels in plant based diets. A 16-week feeding trial was conducted to test increasing inclusion levels of DHA Natur (ADM; Clinton, IA) on growth performance and lipid digestibility in Atlantic salmon. Experimental diets were formulated to satisfy the nutritional requirements of Atlantic salmon parr. The diets contained approximately 45% protein and 27% lipid and were formulated to contain 0%, 5%, 10%, and 15% ADM DHA Natur. Each tank (n = 24) was stocked with 20 fish and quadruplicate tanks were fed one of the experimental diets. Fish in each tank were bulk-weighed and counted every 4 weeks during the trial. At the conclusion of the trial, 3 fish from each tank were homogenized for composition of proximate analysis. A digestibility test was also conducted. The apparent digestibility coefficient of lipid was 66.4% for DHA Natur. The performance of the fish fed the different dietary treatments did not vary significantly (Table 1). The average weight ranged from 410 g to 457 g, weight gain 131 g to 167 g, percent gain 46% to 60%, feed efficiency 0.86 to 1.13, and thermal growth coefficient 1.04 to 1.08. Overall, there were no significant difference in body composition, hepatosomatic index, or intestinal length/fork length ratio. Adding DHA Natur to the diets of Atlantic salmon provide DHA at levels comparable to marine based control feed did not affect performance or proximate composition of the fish.