Evaluación del crecimiento del pulpo común Octopus mimus del norte de Chile alimentado con dietas formuladas

The growth and survival of juvenile octopus, Octopus mimus, from northern Chile, fed three different diets were analyze during 57 days. Two of the diets (A and B) were wet diets stuffed in lamb gut with a gelatin solution, and the third (C) was a natural control. Diet (A) was a mixture of chopped fish meat (Cheilodactylus variegatus) and pellets of salmon meal; diet B was made up of clam (Protothaca thaca) mixed with C. variegatus meat; and diet (C) (control) consisted of fresh frozen clams. The experimental design was based on repetitive measures; the octopuses were supported individually 70-L tanks, with constant sea water circulation and aeration. The octopuses fed diet B did not registred mortality, whereas those fed the control (diet C) presented a mortality of 16.7%. Growth rates were similar (P > 0.05) for these two groups, with absolute growth rates (AGR) of 7.0 ± 0.91 (g d -1 ) and 6.6 ± 1.10 (g d -1 ), respectively. The octopuses fed diet A had a mortality of 33.3% and an AGR of -1.70 ± 0.37 (g d -1 ). Diet A, which contained pellets of ground salmon meal, was not well-accepted, and the weight of the octopuses in this group declined. Diet B, prepared with gelatin from animal origins, was no less palatable or acceptable than the control diet of fresh frozen clams, and the individuals in these two groups showed similar growth. These results will allow us to improve the nutritional quality of artificial diets in order to maximize the growth of O. mimus in captivity.