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One of the major problems involved in the controlled cultivation of Patagonian red octopus (Enteroctopus megalocyathus) is its long embryonic period ranging between 150-176 days, after which the hatching of planktonic paralarvae is achieved. The effect of temperature on the incubation of E. megalocyathus eggs was studied with the aim of establishing if a temperature higher than 12°C is effective to accelerate the embryonic development without altering their morphological and physiological conditions. Fertilized eggs obtained under controlled conditions at 11°C AE 0.1 were randomly distributed in 12 water baths of 30 L at 4 temperatures: 12, 14, 15 and 16°C AE 0.1°C. The experiment lasted until egg hatching occurred.The embryo growth rate was accelerated at 15-16°C, so the time spent in embryonic development can be reduced in 15% when compared with embryo development obtained from eggs incubated at 12°C. The embryos showed no significant differences in the final survival and were morphometrically similar in all stages of development at all temperatures. The increase in temperature from 12 to 16°C, even if it allowed a better growth, had high metabolic costs for embryos of E. megalocyathus. The activities of lipases and proteases were affected by interaction between temperature and the embryo stage, with high lipase activity observed in embryos of stage XV incubated at high temperatures and the highest levels of trypsin and chymotrypsin in stage XX at 14°C. The results suggest that 15°C could be the limit temperature to increase growth.

We propose two hypotheses to explain the inexistence of adequate prepared diet for Octopus maya at this date: Hypothesis 1 is related to changes in protein structure during protein cooking, which affects the digestibility. Hypothesis 2 is related to changes on nutritional characteristics during ingredient process, which affects the nutritional composition of diet. To test hypothesis 1, experiments one and two were directed to determine if protein cooking reduces digestibility and growth of animals when compared to fresh or lyophilized protein sources. For hypothesis 2, three experiments were conducted, testing seven different dietary protein sources offered in isolation or combined in artificial diets fed to O. maya. Results demonstrated that the diets that promoted growth were the ones based on fresh crab paste, and both lyophilized crab and squid tentacles paste. In consequence hypothesis 1 was accepted. The cooking process also changed nutritional characteristics of protein sources, affecting the growth of O. maya. Results obtained when squid and crab were mixed suggest that nutritional requirements of octopuses were covered with that diet in similar forms compared to when using fresh or lyophilized crab, also confirming hypothesis 2. Based on growth rates obtained, we can conclude that nutritional requirements of O. maya must be between 80% and 86% Protein (P), 5.1–5.6% Lipids and a protein: energy ratio between (P/E) 38.9 and 42.2 g MJ−1.

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The aim of this study was to evaluate the performance of Patagonian octopus fed with moist diets formulated with several local feed ingredients. All formulated diets were based on crab paste (70%) and the experimental feed ingredient (30%). Experiment 1 assayed salmon meal, prime sardine meal, and wheat gluten, using fresh fish as a control; experiment 2 assayed prime fish meal and macroalgal meal against crab paste alone as a control. The ingestion rate was lower than expected for all diets except those of fresh fish, crab paste alone, and crab paste plus prime sardine meal. No significant differences were found in the observed digestibility of the diets, indicating, in general, low digestibility, even for fresh fish. The highest protease values were observed for crab paste plus prime sardine meal in both experiments. The better growth of Enteroctopus. megalocyathus was obtained when these were fed fresh fish, which was associated with the greater consumption observed in this diet, as neither the digestibility nor the enzymatic activities of the hepatopancreas were related to this greater growth.

The increasing market demand for cephalopods and the experiences obtained with different species has boosted the interest in developing their culture in Latin America. In 2008, an international workshop was held in Puerto Montt, Chile, with 14 experts in experimental cephalopods aquaculture from Brazil, Chile, Spain, and Mexico. Several topics were approached within the holobenthic species Octopus maya and the merobenthic species Enteroctopus megalocyathus, Octopus vulgaris, and Robsonella fontaniana. Part of the conclusions demonstrated that the two greatest difficulties for their production were survival of paralarvae for merobenthic species, and survival of early juveniles for holobenthic species . Besides, there is a need to study the endogenous and exogenous factors affecting health and nutritional status of embryos, paralarvae, and juveniles. These stages, which may limit the culture, should be extensively studied in order to develop the appropriate environmental conditions and culture systems for the physiological and behavioral requirements, from egg incubation up to juveniles to reach a grow-out phase.