Substituição da farinha de peixe por hidrolisado proteico de peixe em rações para o camarão marinho Litopenaeus vannamei na fase de berçário

Abstract

The depletion of fisheries combined with growing demand from aquaculturists for fish meal to manufacture feed has led to increased costs for this product. In the search for ways to make aquaculture less dependent on fisheries, several alternative raw materials are being used to manufacture feed for fish and crustaceans. In this study we used tilapia carcasses from fish filleting operations to produce fish protein hydrolysates and subsequently incorporated them into feed for marine post-larval shrimp. Two fish protein hydrolysates were produced (FPH) with hydrolysis times of 1 (FPH1) and 2 hours (FPH2). The commercial protease alcalase was used in the reaction. The hydrolysates obtained were subjected to structural and nutritional analysis. The following data were determined: degree of hydrolysis, electrophoretic profile, zymography, composition (to the hundredth), and levels of amino acids and fatty acids. The degree of hydrolysis obtained ranged from 34.01 to 48%. Peptides from 10 to 250 kDa were detected, and 4 bands were observed in the zymography for each hydrolysate, with weights ranging from 75 to 250 kDa. The levels of crude protein hydrolysates were 68.04% (FPH1) and 70.69% (FPH2). Next, experimental feeds were prepared containinggradual substitutions of fish meal with the hydrolysates FPH1 and FPH2 in the proportions of 0% (control), 10%, 20%, and 30%, totaling seven formulated feeds (0%, H110%, H120%, H130%, H210%, H220%, and H230%). These feeds were fed to marine shrimp in the initial post-larvae phase 12 for 45 days. At the end of the crop, the performance of the shrimp fed the experimental feed was evaluated. We found that the shrimp fed the formulations containing FPH2 had better growth than the other treatments, proving that hydrolysate can be used in feed for post-larvae stage Litopenaeus vannamei, replacing 15% of fish meal.