Feeding Channel Catfish, Ictalurus punctatus, Diets Amended with Refined Marine Fish Oil Elevates Omega‐3 Highly Unsaturated Fatty Acids in Fillets

Abstract

Abstract Channel catfish, Ictalurus punctatus, 88.4 ± 2.6 g/fish, were fed a basal diet amended with 4% of three processed menhaden, Brevoortia tyrannus, oils. These were compared with basal diets amended with 4% corn oil or 4% canola oil. Three replicate aquaria of nine fish each were fed assigned diets twice daily. At 6 wk, fish were group weighed, fillets were collected for sensory evaluation, fatty acid analysis by gas chromatography (GC). In a second study, catfish, 118.8 ± 3.2 g/fish, were stocked into fifteen 0.04‐ha earthen ponds and fed once daily for 16 wk one of four diets containing 2 or 4% of either catfish offal oil or refined (RF) menhaden oil. At harvest, fillets were saved for sensory evaluation and fatty acid analysis. Results showed no significant (P > 0.05) differences among treatments for aquarium study and pond study variables such as weight gain, fillet proximate analysis, or pond production. GC analysis showed that levels of omega‐3 (n‐3) highly unsaturated fatty acids (HUFA) in fillet lipid were significantly (P < 0.05) elevated for fish fed menhaden oil diets. Sensory evaluation revealed that fillets from fish fed RF menhaden oil had satisfactory flavor and could be a source of n‐3 HUFA for humans.