Practical diets for the sustainable production of brown shrimp, Farfantepenaeus californiensis, juveniles in presence of the green macroalga Ulva clathrata as natural food

This study evaluated five experimental diets (40 % protein, 11 % lipids): the first diet (FM) was formulated with 10 % fish meal content and no fish oil; the second diet (FO) contained 0.5 % fish oil, while fish meal was totally replaced with poultry by-product meal; the third (DHA) and the fourth (LO) diets were formulated to replace fish oil with 0.5 % microalga oil and 0.5 % linseed oil, respectively; the fifth diet (SLO) used soybean meal and corn gluten as main protein sources, with 0.5 % linseed oil. A conventional, commercial-like diet (Ctrl) included 36 % fish meal and 1.4 % fish oil (36 % protein, 7.5 % lipids). Brown shrimp Farfantepenaeus californiensis juveniles (0.12 g) were stocked into 50-L tanks at ten shrimp tank −1 , and eight feeding treatments were applied: shrimp fed Ctrl diet ad libitum (100 % pelleted feed ration: CtrlA); shrimp fed a 50 % ration of Ctrl diet (CtrlB), FM, FO, DHA, LO, or SLO in presence of fresh Ulva offered ad libitum; and, finally, shrimp fed only fresh Ulva (UC). After the 8-week feeding trial, survival was over 87 %; CtrlA, CtrlB, FM, and SLO treatments presented significantly better growth ( p