The ingredients used for each semi humid paste were ground in a laboratory mill (Thomas Willey Mod. 4, USA) to particles < 0.5 mm in diameter, and their moisture, total protein, total lipids, and ash contents were determined following methods established by A.O.A.C. (protocols 934.01, 976.05, 920.39 and 942.05, respectively). The diets were prepared by thoroughly mixing ingredients with purified water (200 ml to crab paste, squid paste, crab–squid paste and 125 ml to silage squid paste and silage–crab–squid paste) until a semi-moist diet resulted, with gelatin used as agglutinant (4.5%). Gelatine was first pre-gelatinised with cold water and after added to the dry ingredients during mixed with the rest of water.