Development of anin vitromodel to assess protein bioavailability in diets for common octopus (Octopus vulgaris)

Abstract

An in vitro model designed to assess protein bioavailability in diets for growing Octopus was developed. The model required a previous assessment of some functional features of protein digestion in this species like the main producing organs, optimum pH for activity and total production per g tissue. The main producing organs identified were the salivary glands and the hepatopancreas (HP), being optimum pH for protease activity quite different in both organs (mostly alkaline in the posterior salivary glands and acid in the HP). In spite of the high-specific protease activity measured in the salivary glands, a major role of the HP in protein hydrolysis is suggested due to the much bigger size of this viscera. All this information was used as a basis to develop an in vitro two-step hydrolysis process, which simulated protein hydrolysis performed by these two organs using the Octopus enzymes. The assay was used to evaluate differences in amino acid bioavailability from several protein sources (casein, gelatin, fish meal, squid meal and krill meal) that could be used as feed ingredients for this species. As significant differences were detected both in total amount and in rate of release of the amino acids from such proteins, the model is proposed as a complementary tool in the selection and nutritional evaluation of protein ingredients to be used in diets for Octopus.

Performance of Marine Lecithin Supplemented Feeds for the Common Octopus (Octopus vulgaris) Ongrowing: Changes in Proximate Composition and Lipid Classes’ Profile

“…In contrast, protein ADC diminished significantly when soybean lecithin was added, at a same level of inclusion, in feeds for octopus [54]. In addition, the high protein ADCs obtained in the present study (above 0.94) agree with preceding coefficients (over 0.9) already reported in O. vulgaris [9,10,40], verifying a high protein digestion effectiveness in this species [59][60][61][62].…”

Utilization of diets with different fish oil content in common octopus (Octopus vulgarisCuvier, 1797) and resulting changes in its biochemical composition

“…Protein digestibility was above 95% for all the diets assayed, the value coinciding with those found for natural diets (Hernández & García García ; Mazón, Piedecausa, Hernández & García García ; Sánchez, Hernández, Cerezo Valverde & García García ) and experimental diets (Seiça Neves, Cerezo Valverde & García García ; Morillo‐Velarde et al . ), underlining the efficient enzymatic ability of O. vulgaris to digest these nutrients (Boucher‐Rodoni ; Aguila, Cuzon, Pascual, Domíngues, Gaxiola, Sánchez, Maldonado & Rosas ; Hamdan, Tomás‐Vidal, Martínez, Cerezo Valverde, Moyano & Moyano ). Our results suggest that the ADCPROT were not significantly affected by the content of lipids in the diet (Fig.…”

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

“…For wild sub-adults of O. vulgaris , it was recently demonstrated that dehydration of raw materials at temperatures lower than 60°C induced similar growth rates when compared to freeze dried ingredients (Rodriguez-González et al, 2015), indicating that protein characteristics are correlated with the digestive capacity of the animals. Although, there are many papers related to important ingredients (amino acids, lipids) for O. vulgaris feed (Cerezo-Valverde et al, 2012a,b, 2013; Estefanell et al, 2013; Querol et al, 2013; Hamdan et al, 2014; Rodriguez-González et al, 2015) there is a general lack of knowledge of the physiological processes involved during nutrient digestion in octopus species. Considering that protein digestion is a key aspect of cephalopod nutrition, the study of the process by which proteins (and other nutrients) are digested and assimilated will determine diet design (Martínez et al, 2014).…”