Fish, fish meal and vegetable meals had lower chemical scores explaining, at least in part, the worse result that those ingredients provoked in O. vulgaris. Using the criterion of Cerezo-Valverde et al. (in press) and Callinectes sapidus crab, jumbo squid D. gigas and O. maya amino acids data obtained by Aguila et al. (2007) and Cordova-Murueta et al. (2003)