Effects of alternative dietary lipid sources on performance, tissue chemical composition, mitochondrial fatty acid oxidation capabilities and sensory characteristics in brown trout (Salmo trutta L.) Giovanni M. Turchini a, * , Tiziana Mentasti a , Livar Frøyland b , Elena Orban c , Fabio Caprino a , Vittorio M. Moretti a , Franco Valfre ´ a a Dipartimento di Scienze e Tecnologie Veterinarie per la Sicurezza Alimentare, Facolta ` di Medicina Veterinaria, Universita ` degli Studi di Milano, Via Trentacoste 2, 20134 Milan, Italy b Institute of Nutrition, Directorate of Fisheries, N-5804 Bergen, Norway c National Institute of Nutrition, Unit of Study on the Quality of Fish as Food, Via Ardeatina 546, 00178 Rome, Italy Abstract The efficiency of five dietary lipid sources (fish oil as control—C; canola oil—CO; poultry fat—PF; pork lard—PL; and oleine oil—OO) were evaluated in juvenile brown trout (58.4 F 0.7 g) in an experiment conducted over 70 days at 14.6 F 0.4 jC. The best growth was observed in fish fed the C diet whereas the PL diet fed fish had the best feed utilization. Significant differences in carcass and muscle proximate composition, but not in liver, were noted among fish fed the different dietary treatments. The fatty acid composition of muscle largely reflected that of the diets, while total cholesterol was not affected. The atherogenicity and the thrombogenicity qualities of the trout flesh were modified by the lipid sources. Sensory analysis did not show any significant differences among the cooked fillets with respect to dietary treatments, while in uncooked products, some significant differences were observed. The carnitine palmitoyltransferase I and II (CPT-I and CPT-II) activities of liver and white muscle were assayed for a better understanding of the potential h-oxidation capability of the different dietary lipid sources. The hepatic, but not white muscle CPT-I and CPT-II activities were affected by dietary treatments. This 0044-8486/03/$ - see front matter D 2003 Elsevier Science B.V. All rights reserved. doi:10.1016/S0044-8486(03)00294-1 * Corresponding author. Tel.: +39-2-50315761; fax: +39-2-50315746. E-mail address: giovanni.turchini@unimi.it (G.M. Turchini). www.elsevier.com/locate/aqua-online Aquaculture 225 (2003) 251 – 267