Evaluating the Effects of Formulated Moist Diets on Juveniles of Patagonian OctopusEnteroctopus megalocyathus(Gould 1852)

Abstract

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.

Effects of dietary protein sources on growth, survival and digestive capacity ofOctopus mayajuveniles (Mollusca: Cephalopoda)

“…() for S. officinalis with increase chemotrypsin activity when feeding cooked shrimp, and increase trypsin activity when feeding frozen raw shrimp. In another study on the sub polar Patagonian octopus ( Enteroctopus megalocyathus), Farías, Pereda, Uriarte, Dörner, Cuzon and Rosas () reported low digestive gland chymotrypsine activity both in octopus fed diets that promoted growth and diets that resulted in negative growth rates. During that study, it was also observed that the growth rate was only related to ingestion rate and not to digestive gland enzyme activity or dietary digestibility.…”

Replacing live feed with formulated diets in juvenile Patagonian red octopus (Enteroctopus megalocyathus)

“…Two formulated diets and a natural diet (C) consisting of live specimens of Chilean crab Cancer edwarsii were used in the experiment. The formulated diets (Table ) were CP and C&S, consisting of two experimental formulations based on crab meat paste (Farías et al., ) and a mixture of freeze‐dried crab and squid ( Dosidicus gigas ) meals (Rosas et al., ), respectively.…”

“…The best growth rates in juvenile stages have been reported in O. maya (Martínez et al., ) using a moist crustacean‐based diet (3.04 %/day), followed by O. vulgaris (Biandolino et al., ), and E. megalocyathus (Pérez et al., ) with both being fed a natural diet (1.93 %/day and 1.36 %/day, respectively), and finally O. mimus (Zúñiga et al., ) with a moist agglutinated diet (0.7%/day). The lowest growth rates have been attributed to low acceptability (Farías et al., ; López, Rodríguez, & Carrasco, ; Pérez et al., ), low conversion rate (Domingues, García, et al., ) and low digestibility (Martínez et al., ).…”

“…The artificial feeding of the Patagonian red octopus E. megalocyathus is a challenge due to the low growth rates obtained using different moist‐based diets (Farías et al., ). To date, species such as O. maya and O. vulgaris have acceptable development rates using moist formulated diets, allowing them to replace the fresh natural diet at an experimental level.…”

“…To date, species such as O. maya and O. vulgaris have acceptable development rates using moist formulated diets, allowing them to replace the fresh natural diet at an experimental level. Regarding E. megalocyathus , the juvenile similarly digests formulated feeds with vegetable, seaweed and animal ingredients (Farías et al., ); however, their consumption and growth rates were lower than those fed fresh fish. In the case of O. maya , Linares et al.…”