Dietary protein source and protein/carbohydrate ratio affects appetite regulation-related genes expression in gilthead seabream (Sparus aurata)

This study aimed to evaluate the effect of dietary protein source (fishmeal, FM; or plant-feedstuffs, PF) and protein/carbohydrate (P/CH) ratio on gilthead seabream appetite regulation intermediary metabolism. Additionally, sampling 5 h after feeding (AF) compared 24 AF was also evaluated. Four isolipidic diets were formulated having as major sources FM PF (20% 80% PF), P/CH ratios 50/10 40/20, being pregelatinized maize starch main carbohydrate (diets FM-P50/CH10; FM-P40/CH20; PF-P50/CH10; PF-P40/CH20). Diets fed until satiation 140 g for 41 days. The expression genes assessed at AF, while other evaluated parameters only AF. Liver leptin higher brain receptor ( lepr ) Brain cocaine- amphetamine-regulated transcript cart ), ghrelin ghrr )- a liver ghrr-b affected by time, but effects dependent diet provided. FM-based promoted (at AF), growth hormone ghr -ii , increased plasma cholesterol total lipids levels. Fish PF-based had glycogen content, number size adipocytes, hepatic fatty acid synthase glucokinase target rapamycin . Regarding ratio, fish P50/CH10 presented feed efficiency, triglycerides, intestine cholecystokinin glutamate dehydrogenase ghr-ii efficiency hepatosomatic visceral indices, plasmatic glucose level, AF) in P40/CH20 diets. majority related-genes not use diets, CH seemed lead shorter satiety sensation. lipid deposition, hypocholesterolemia, activation glycogenesis pathway, content induced an increase that appeared be stored lipids. In conclusion, with up 20% can used without compromising performance FI, slightly modifying metabolic parameters. • ghrr-a time. Response took more time induced. High CH-diets did affect FI expression.