Growth and feed efficiency of Octopus vulgaris fed on dry pelleted

Abstract

The purpose of this study was to evaluate the effect of two dry extruded diets on growth and nutritional composition of digestive gland (DG) and muscle of Octopus vulgaris. Both artificial diets (FMK and 3FMK) were composed of gelatin, maltodextrin, yolk, fish and krill meal. The 3FMK diet contained more fishmeal (3x) than the FMK diet. These diets were compared with a control frozen diet consisting of golden grey mullet (Liza aurata) and crab (Liocarcinus depurator). The 3FMK diet promoted higher intakes and feed efficiency than FMK diet, resulting in larger growths (296 respect to 158g in 42days; 0.81% vs. 0.78% body weight/day). There was significantly lower moisture, protein and ash content in digestive glands of animals fed pellets (P<0.05). No significant differences were observed on nutritional composition of muscle among the three groups. Even though the results were still below those of the control group (increase of 1258g), the good performance in terms of acceptance and growth showed that this extruded diet can be the starting point to develop a commercial feed for this species.