Digestive Physiology of Octopus maya and O. mimus: Temporality of Digestion and Assimilation Processes

Abstract

Digestive physiology is one of the bottlenecks of octopus aquaculture. Although, there are successful experimentally formulated feeds, knowledge of the digestive physiology of cephalopods is fragmented, and focused mainly on Octopus vulgaris. Considering that the digestive physiology could vary in tropical and sub-tropical species through temperature modulations of the digestive dynamics and nutritional requirements of different organisms, the present review was focused on the digestive physiology timing of Octopus maya and Octopus mimus, two promising aquaculture species living in tropical (22–30°C) and sub-tropical (15–24°C) ecosystems, respectively. We provide a detailed description of how soluble and complex nutrients are digested, absorbed, and assimilated in these species, describing the digestive process and providing insight into how the environment can modulate the digestion and final use of nutrients for these and presumably other octopus species. To date, research on these octopus species has demonstrated that soluble protein and other nutrients flow through the digestive tract to the digestive gland in a similar manner in both species. However, differences in the use of nutrients were noted: in O. mimus, lipids were mobilized faster than protein, while in O. maya, the inverse process was observed, suggesting that lipid mobilization in species that live in relatively colder environments occurs differently to those in tropical ecosystems. Those differences are related to the particular adaptations of animals to their habitat, and indicate that this knowledge is important when formulating feed for octopus species.

Sexual maturation and embryonic development in octopus: use of energy and antioxidant defence mechanisms usingOctopus mimusas a model

“…For this reason we hypothesise that, as in DG (Martinez et al, 2014) in the ovarium part of the glycogen and glucose registered followed the glycogenic pathways (Hochachka & Fields 1982) (Fig. 9),as was previously described in muscle of different cephalopod species (Gallardo et al 2017; Hochachka & Fields 1982; Morales et al 2017).…”

“…This finding suggests that these processes require high levels of metabolizable energy. Accordingly, glycogen and glucose in the digestive gland of O. mimus and O. maya , as well as soluble proteins were used as a source of metabolic energy during digestive processes (Gallardo et al 2017) and growth of juveniles and pre-adults of O. maya (Aguila et al 2007; Rosas et al 2011). Hence the importance of those nutrients in the physiology of cephalopods.…”

“…There is a fair knowledge on production and rearing of O. mimus paralarvae in controlled conditions; for instance, environmental variables, type of tanks, light, diet (Cortez et al 1995; Olivares et al 1996; Zuñiga et al 1995), histology, biochemistry and reproduction (Cortez et al 1995; Olivares et al 2017; Olivares et al 2003; Olivares et al 2001; Zamora & Olivares 2004). Recent studies have progressed on embryo development (Castro-Fuentes et al 2002; Uriarte et al 2012; Warnke 1999), thermal tolerance of paralarvae (Zuñiga et al 2013), growth and nutrition (Baltazar et al 2000; Carrasco & Guisado 2010; Gallardo et al 2017), taxonomy and genetics (Perez-Losada et al 2002; Söller et al 2000). Those studies were stimulated due to the potential for aquaculture of O. mimus in Chile and to better understand the potential effects of environmental changes in the natural populations.…”

Anatomical and histochemical features of the digestive system ofOctopus vulgarisCuvier, 1797 with a special focus on secretory cells

“…Most of these studies focus on structural changes in the digestive cells and the abundance of inclusions during the digestive process (Bidder, ; Boucaud‐Camou & Boucher‐Rodoni, ; Boucaud‐Camou & Yim, ; Semmens, ; Semmens et al., ). As in other cephalopods (Gallardo et al., ; Martínez et al., ), the digestive gland acini of O. vulgaris are characterised by a single type of columnar cell. Bidder () reported that the digestive gland of O. vulgaris displays several rhythmic activities during the digestion process.…”

Early life stage bottlenecks of carnivorous molluscs under captivity: a challenge for their farming and contribution to seafood production

“…When O. mimus (temperate habitat) and O. maya (tropical habitat) were compared, it was evident that the timing of the digestive process and the type of digestion changed with the species, being more important the digestion of lipids in the case of temperate species and of protein in tropical ones (Gallardo et al . ). This process affects the content of AA in blood and the synthesis of complex molecules in the muscle (glycogen and protein), indicating the importance of soluble nutrients and complex nutrients in the design of complete feeds for these species (Martínez et al .…”