Olive Pomace and Soybean-Sunflower Acid Oils as Alternative Fat Sources in European Seabass ( Dicentrarchus labrax ) Diets: Effects on Performance, Digestibility and Flesh Fatty Acid Composition and Quality Parameters

• Published in: Animals (Basel) Vol. 12; no. 9; p. 1198
• Main Authors: Verge-Mèrida, Gerard, Barroeta, Ana Cristina, Ferrer, Carlos, Serrano, Tània, Guardiola, Francesc, Soler, María Dolores, Sala, Roser
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 06-05-2022; MDPI
• Subjects: acid oil; alternative energy source; Animals; Aquaculture; By products; Composition; Conversion ratio; Dicentrarchus labrax; Diet; dietary fat; Digestibility; Dry matter; Edible oils; Energy sources; fat by-product; Fatty acid composition; Fatty acids; Feed conversion; Feeds; Fish diets; Fish farms; Fish oils; flesh quality; free fatty acid; Helianthus; Impurities; Ingredients; Lipids; Oils & fats; Olive oil; Petroleum refining; Soybean oil; Soybeans; Sunflowers; Vegetable oils; Spain; fat by-product; flesh quality; acid oil; dietary fat; free fatty acid; alternative energy source; fish nutrition
• ISSN: 2076-2615; 2076-2615
• DOI: 10.3390/ani12091198

The effects of dietary inclusion of soybean-sunflower and olive pomace acid oils on growth, digestibility and flesh composition were studied in European seabass. Eight diets were fed for 100 days (101.37 ± 0.33 g initial weight, mean ± SD), differing in the added fat source (25% fish oil, 75% experimental oil): S (crude soybean oil), SA (soybean-sunflower acid oil), O (crude olive pomace oil) or OA (olive pomace acid oil); 3 blends: S-O, S-OA, SA-OA at a 1:1 ratio; and a diet containing only fish oil (F) as a control. Animals fed OA showed the worst performance among dietary treatments, with the lowest weight, specific growth ratio, average daily gain and the highest feed conversion ratio (p < 0.01). In contrast, other diets including acid oils did not impair performance. Acid oil diets did not affect the apparent digestibility of dry matter, crude protein or total fatty acids (p > 0.05), but a lower digestibility of lipids and saturated fatty acids was observed (p < 0.001). Flesh composition and fatty acid profile were not affected by the high dietary free FA content (p > 0.05). Hence the results suggest that the studied acid oils may potentially be used in fish diets although further studies are needed.