Alternative sources of fatty acids in lipid metabolism and performance of cobia juveniles, Rachycentron canadum

• Grant number: 21/00424-1
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: October 01, 2022
• Status: Discontinued
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Alexandre Wagner Silva Hilsdorf
• Grantee: Micheli Zaminhan Hassemer
• Host Institution: Pró-Reitoria Acadêmica. Universidade de Mogi das Cruzes (UMC). Campus da Sede Mogi das Cruzes. Mogi das Cruzes , SP, Brazil
• Associated scholarship(s): 24/10083-5 - Hydrolyzed poultry protein in the diet of gilthead seabream (Sparus aurata), BE.EP.PD

Abstract

The use of fish oil (FO) in marine animals nutrition is directly related to the high nutritional requirements for long chain and highly unsaturated fatty acids of the n-3 series (LC-PUFAs n-3). However, the FO production is in decline, and alternative and lower cost lipid sources such as vegetable oils (VO) have been intensively investigated. However, in most cases, this replacement negatively impacts fish growth changing lipid metabolism, mainly influenced by high amounts of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated n-6 series (PUFA n-6), and inversely to the absence of LC-PUFAs. An alternative option to minimize the negative impacts occasioned by FO replacement is to produce diets that meet the nutritional requirements of this species, using VO supplemented with LC-PUFAs. Studies with marine fish showed that diets with high amounts of SFA, MUFAs and n-6 PUFA series, even supplemented with LC-PUFAs, alter lipid deposition in the liver and intestine as well as the expression of genes related to the fatty acid synthesis and oxidation. Based on that this proposal aims to investigate the metabolic responses of cobia juveniles (Rachycentron canadum) during the postprandial period and analyze the effects of alternative lipid sources supplemented with LC-PUFAs on performance, lipid metabolism and expression of genes related to fatty acid synthesis and oxidation on the liver of cobia juveniles, verifying the influence of different C18 PUFA n-6/LC-PUFAs ratios in FO-free diets.