REEVALUATING THE ESSENTIAL FATTY ACID REQUIREMENTS OF FLORIDA POMPANO Trachinotus carolinus

Numerous alternative lipid sources have been identified as suitable replacements for fish oil in the production of aquafeeds, however, they often do not provide significant amounts of essential fatty acids (EFA). Accordingly, we evaluated the growth performance of Florida Pompano fed diets containing different combinations of n-3 and n-6 C₁₈ polyunsaturated fatty acids (C18 PUFA) or long-chain polyunsaturated fatty acids (LC-PUFA). Diets varied only in lipid source and composition, containing menhaden fish oil (positive control, "FO Control"), hydrogenated soybean oil (negative control, "EFA-Free Control"), or soybean oil amended with ethyl esters of 18-3n:3 ("ALA"), 18:2n-6 and 18:3n-3 ("C18 PUFA"), 22:6n-3 ("DHA"), 22:6n-3 and 20:4n-6 ("ARA+DHA"), or 22:6n-3, 20:4n-6, and 20:5n-3 ("LC-PUFA"). Diets were randomly assigned to triplicate tanks (N=3) of Florida Pompano (8 fish/tank; 47.4 g/fish), fish were fed a fixed ration of 4% body weight per day split between two feedings for 7 weeks. At harvest, individual fish weights were collected to analyze growth performance. Data were analyzed by one way analysis of variance, followed by Tukey's HSD test when omnibus tests indicated significant treatment effects (P < 0.05).

As anticipated, fish fed the FO Control experienced significantly greater weight gain (223.4%) compared to those fed the EFA-Free Control diet (147.1%; Figure 1). Although not significantly different, fish fed the LC-PUFA and ARA+DHA diets gained more weight (173%) than the negative control group (Figure 1). Results from this trial indicate that Florida Pompano benefit from the inclusion of intact dietary LC-PUFA.