Pelleted diet with thermal treatment of ingredients for Octopus americanus: Growth performance and enzymatic activity

摘要

The octopuses are an emergent group for marine aquaculture diversification. One of the main factors limiting their commercial production is the absence of pelleted or extruded diets that are capable of promoting adequate survival and growth. We tested a pelleted diet with ingredients dried at 40 degrees C and a semi-moist diet based on of raw ingredients (control diet) on the growth performance and activity of digestive enzymes in Octopus americanus subadults. Compared to the semi-moist diet, the pelleted diet was well accepted and presented greater stability in the water and lower leaching. Both diets provided similar growth, survival, feed efficiency and conversion rates, although the total ingestion rate and protein and energy intake rates were higher in octopuses that were fed the semi-moist diet. Furthermore, the pelleted diet stimulated higher activity of acidic proteolytic enzymes, and chymotrypsin activities in the caecum as a physiological response to improve nutrient absorption and assimilation. Therefore, such a diet could be utilized as a starting point to design formulated diets for octopus.