Serhat Turkmen, Maria J. Zamorano, Hanlin Xu, Hipolito Fernandez-Palacios, Lidia Robaina, Sadasivam Kaushik, and Marisol Izquierdo
Environmental factors such as nutritional interventions during early developmental stages affect and establish long-term metabolic changes in all animals. Diets used during the spawning period causes a nutritional programming effect in offspring of gilthead sea bream and affects long-term metabolism. Studies showed modulation of genes such as fads2 which is considered to be a rate-limiting step in the synthesis of n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA). However, it is still unknown whether this adaptation is related to the presence of precursors or limitations in the pre-formed products, n-3 LC-PUFA, contained in the diets used during nutritional programming. This study investigates the combined effects of nutritional programming through broodstock diets during the spawning period and broodfish showing higher or lower fads2 expression levels in the blood after 1-month feeding with a diet containing high levels of plant protein sources and vegetable oils (VM/VO). Broodfish showing high fads2 expression had a noticeable improvement in the spawning quality parameters as well as on the growth of 6 months old offspring when challenged with a high VM/VO diet. Further, nutritional conditioning with 18:3n-3 rich diets had an adverse effect in comparison to progeny obtained from fish fed high fish meal and fish oil (FM/FO) diets, with a reduction in growth of juveniles. Improved growth of progeny from the high fads2 broodstock combined with similar muscle fatty acid profiles is an excellent option also for tailoring and increasing the flesh n-3 LC-PUFA levels to meet the recommended dietary allowances for human consumption.