Label free shotgun proteomics to disclose the impact of methionine-enriched diets in the liver of European seabass

Plant-based protein sources play an important role in aquaculture by dwindling fish meal to sustainable levels. However, the use of such feedstuffs requires nutrient supplementation to fulfil fish nutritional requirements. This work addressed the response in the liver of farmed fish to dietary methionine (Met), assessing at the same time the growth performance. Fish were fed at suboptimal levels of dietary Met (0.77% w/w; M0.65 diet), within (1% w/w Met; M0.85 diet)and above(1.36 % w/w Met (M1.25 diet); 1.66% w/w Met(M1.5 diet)) the estimated requirement for this species, in a total of four tested conditions. The impact of dietary methionine supplementation in seabass juvenile’s performance was assessed through 85 days of trial, between May and August of 2018. Fish were reared in triplicate tanks and three liver samples/tank (9 per treatment) were collected for liver proteome analysis at the end of the trial i.e., after 85 days of feeding.