Efecto de ácidos grasos poliinsaturados en el metabolismo de tilapia nilótica (Oreochromis niloticus) alimentados con dietas suplementadas con diferentes fuentes de aceite vegetal

Abstract

Fish farming is a growing economy that requires large quantities of fishmeal and fish oil, increasing the extraction of pelagic fish, negatively impacting marine ecosystems, making fish production environmentally and economically unsustainable. It is necessary to search for new diets that reduce pollution and the use of fish as food in fish farming systems. The objective of this research was to evaluate the effects of different vegetable sources of fatty acids (FA) in the diet on the metabolism of tilapia broodstock cultured in a recirculating water system (RAS). Thirty-two 250 L experimental units were used, with 20 fish each, distributed in 16 tanks for males, 16 for females; 4 treatments supplemented with 4 sources of FA (palm oil (PA), corn oil (MA), sacha oil (SA) and sacha-maize oil (SAM)), each treatment had four replicates. The effects of AG sources were analyzed in AG profiles in liver, muscle and gonad; fillet proximal composition, fish performance parameters (initial weight (IP), final weight (FP), final size (TF), weight gain (WG), length gain (GL), specific growth factor (SGR %), survival percentage (% S) and feed conversion ratio (FCR)) and metabolic parameters. In general, males presented greater increases in weight, length, and consumption; gonadosomatic and hepatosomatic indices were higher in females. The GA profiles suggest de novo synthesis of GA from 16- and 18-carbon GA. In liver, muscle and gonad, C18:2n-6 and C18:3n-3 FA content decreased in relation to dietary content, while C18:0 increased in tissues. The proximal composition of the fillet did not show outliers. In conclusion, the inclusion of vegetable oils in the tilapia diet modifies lipid profiles, but does not negatively affect fillet proximal composition.