Enzymatic capacities of metabolic fuel use in cuttlefish (Sepia officinalis) and responses to food deprivation: insight into the metabolic organization and starvation survival strategy of cephalopods

Food limitation is a common challenge for animals. Cephalopods are sensitive to starvation because of high metabolic rates and growth rates related to their "live fast, die young" life history. We investigated how enzymatic capacities of key metabolic pathways are modulated during starvation in the common cuttlefish (Sepia officinalis) to gain insight into the metabolic organization of cephalopods and their strategies for coping with food limitation. In particular, lipids have traditionally been considered unimportant fuels in cephalopods, yet, puzzlingly, many species (including cuttlefish) mobilize the lipid stores in their digestive gland during starvation. Using a comprehensive multi-tissue assay of enzymatic capacities for energy metabolism, we show that, during long-term starvation (12 days), glycolytic capacity for glucose use is decreased in cuttlefish tissues, while capacities for use of lipid-based fuels (fatty acids and ketone bodies) and amino acid fuels are retained or increased. Specifically, the capacity to use the ketone body acetoacetate as fuel is widespread across tissues and gill has a previously unrecognized capacity for fatty acid catabolism, albeit at low rates. The capacity for de novo glucose synthesis (gluconeogenesis), important for glucose homeostasis, likely is restricted to the digestive gland, contrary to previous reports of widespread gluconeogenesis among cephalopod tissues. Short-term starvation (3-5 days) had few effects on enzymatic capacities. Similar to vertebrates, lipid-based fuels, putatively mobilized from fat stores in the digestive gland, appear to be important energy sources for cephalopods, especially during starvation when glycolytic capacity is decreased perhaps to conserve available glucose

Octopus vulgaris. Paralarval Culture

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Amino acids composition and protein quality evaluation of marine species and meals for feed formulations in cephalopods

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Current Status and Future Challenges in Cephalopod Culture

11 pagesThis chapter presents an overall perspective on the current status of cephalopod culture, its bottlenecks and future challenges. It focuses on the species that have received more research effort and consequently accumulated more scientific literature during the present century, namely Sepia officinalis, Sepioteuthis lessoniana, Octopus maya and Octopus vulgaris. Knowledge regarding physiology, metabolism and nutrition of different species is still lacking. Two main challenges are identified: the development of a sustainable artificial diet and the control of reproduction. Understanding cephalopod physiology and nutrition will probably be the biggest challenge in developing the large-scale culture of this group of molluscs on a medium to long term. In addition, zootechnical parameters need future research and improvement. The performance of an ethical experimentation with cephalopods is strongly encouraged and any zootechnical development should be performed and adapted accordingly. The potential of cephalopod culture extends far beyond its use for research and human consumption and probably it will be translated in a remarkable production in the coming yearsThis chapter presents an overall perspective on the current status of cephalopod culture, its bottlenecks and future challenges. It focuses on the species that have received more research effort and consequently accumulated more scientific literature during the present century, namely Sepia officinalis, Sepioteuthis lessoniana, Octopus maya and Octopus vulgaris. Knowledge regarding physiology, metabolism and nutrition of different species is still lacking. Two main challenges are identified: the development of a sustainable artificial diet and the control of reproduction. Understanding cephalopod physiology and nutrition will probably be the biggest challenge in developing the large-scale culture of this group of molluscs on a medium to long term. In addition, zootechnical parameters need future research and improvement. The performance of an ethical experimentation with cephalopods is strongly encouraged and any zootechnical development should be performed and adapted accordingly. The potential of cephalopod culture extends far beyond its use for research and human consumption and probably it will be translated in a remarkable production in the coming yearsPeer reviewe

Nutrition as a key factor for Cephalopod Aquaculture

Cephalopods are fast-growing animals, active swimmers and top predators, which require substantial amounts of food. As such, they show high metabolic rates dependent on a carnivorous diet, thus hypothetically linked to a predominant amino acid metabolism. Their body composition is mainly constituted by high levels of total protein, and their lipids, although quantitatively low, reveal the presence of substantial amounts of long-chain polyunsaturated fatty acids. All in all, little is known about their nutritional requirements, especially during the early stages, very prone to high mortalities under culture. This chapter is a brief account of key information concerning relevant points linked to the nutritional requirements that cephalopods have for proteins, lipids, carotenoids, carbohydrates, minerals and vitamins. Moreover, some considerations on populational metabolism are also presented.Peer reviewe