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G. Verriopoulos - One of the best experts on this subject based on the ideXlab platform.

  • investigation of the potential effect of diet body mass and maturity on growth and feed performance of Common Octopus Octopus vulgaris an information theory approach
    Aquaculture Nutrition, 2011
    Co-Authors: Dimitra Petza, Stelios Katsanevakis, N Lykouri, V Spiliotis, G. Verriopoulos
    Abstract:

    The potential effect of body mass (m), maturity stage (ms), food type (ft), food protein (p) and lipid (li) content, and food protein-to-energy ratio, P/E (pe) on Specific Growth Rate (SGR, % day−1), Absolute Feeding Rate (AFR, g day−1), Feed Efficiency (FE, %), Assimilation Efficiency (AE, %), and Protein Retention Efficiency (PRE, %) in the Common Octopus was investigated. Six food types were provided ad libitum: shrimp, squid, hake, mussel, sardine and artificial one (gels made of hydrated squid flour agglutinated with sodium alginate). Estimated SGRs, AFRs, FEs, AEs and PREs were modelled with General Linear Models based on an information theory approach, using m, ms, ft, p, li and pe as potential predictor variables. SGR decreased when m increased; Octopuses fed on shrimps showed the highest SGRs and the ones fed on mussels showed the lowest SGRs. AFR increased with m. Maximum and minimum FEs were observed, when food provided was shrimps and mussels, respectively. Maximum PRE was performed by Octopuses fed on shrimps or sardines and minimum PRE by Octopuses fed on mussels. Octopuses fed on artificial diet reached satisfactory levels of SGR (0.50% day−1) and FE (12.3%).

  • fatty acid composition of the Common Octopus Octopus vulgaris in relation to rearing temperature and body weight
    Aquaculture, 2006
    Co-Authors: H. Miliou, Myrsini Fintikaki, Marios Tzitzinakis, Triantaphyllos Kountouris, G. Verriopoulos
    Abstract:

    Abstract Octopus vulgaris is considered a candidate for aquaculture and its growth performance is dependent upon temperature and body weight. The aim of this study was to investigate the effects of temperature on the fatty acid composition of O. vulgaris in relation to body weight (60–663 g). The experiments were performed in a closed seawater system with controlled temperature (15, 20 and 25 °C). The Octopuses were fed on squid ( Loligo vulgaris ). O. vulgaris showed a high content of polyunsaturated fatty acids (51.32–57.62% total fatty acids), particularly n  − 3 highly unsaturated acids (38.01–52.73% total fatty acids). At each temperature, the proportion of some fatty acids was highly ( P n  − 9, 18:1 n  − 7, 18:2 n  − 6, 20:4 n  − 6, 22:4 n  − 6 and 22:5 n  − 6 decreased, while 20:5 n  − 3 (EPA) and 22:6 n  − 3 (DHA) increased, with increasing body weight at 20 and 25 °C. The opposite was observed at 15 °C. Total polyunsaturated and n  − 3 highly unsaturated fatty acids (HUFA) decreased in larger Octopuses at 15 °C, as well as in smaller Octopuses at 25 °C, whereas total saturated, monounsaturated and n  − 6 HUFA increased. Thus, total unsaturated fatty acids showed a relatively small variation (60.53–63.96% total fatty acids) and the mean unsaturation index was similar at 15 and 25 °C. Arachidonic acid (2.4–9.6% total fatty acids) was inversely related to EPA and DHA, and positively to 18:2 n  − 6, 22:4 n  − 6 and 22:5 n  − 6. It is noted that arachidonic acid is not an essential fatty acid for the Common Octopus. It is concluded that the fatty acid composition of O. vulgaris was influenced by temperature and body weight, but with an n  − 3/ n  − 6 ratio of more than 3 and a DHA/EPA ratio of more than 1.5. The Common Octopus could be an excellent source of arachidonic acid, containing sufficient n  − 3 HUFA levels, in low temperatures for large individuals and in warm temperatures for small ones.

  • combined effects of temperature and body weight on growth and protein utilization of the Common Octopus Octopus vulgaris
    Aquaculture, 2005
    Co-Authors: H. Miliou, Myrsini Fintikaki, Triantaphyllos Kountouris, G. Verriopoulos
    Abstract:

    Abstract Octopus vulgaris is considered a serious candidate for rearing, in terms of its biological and market potential: easy adaptation to captivity conditions, high growth rate and high market price. The aim of this study was to examine the combined effects of temperature and body weight on specific growth rate (SGR, % day − 1 ), absolute growth rate (AGR, g day − 1 ), absolute feeding rate (AFR, g day − 1 ), feed efficiency (FE, %), protein retention efficiency (PRE: [g protein gain g protein ingested − 1 ] × 100), energy retention efficiency (ERE : [kJ gain kJ ingested − 1 ] × 100), proximate composition and P / E ratio (protein/energy) of the Common Octopus. The experiments were performed in a closed system with controlled temperature (15, 20 and 25 °C). The Octopuses were fed on squids ( Loligo vulgaris ). In the multiple regression equations estimated for SGR, AGR, AFR, FE, PRE and ERE , the linear and quadratic effects of temperature, as well as the linear effects of body weight were significant. In addition, the interaction effects of temperature and body weight were significant for SGR, AGR, FE, PRE and ERE; the temperature for maximum response decreased with increasing size, being 25 °C for Octopuses of 50–150 g and 15 °C for animals of 200–600 g. The weight exponent in the relationships of these indices vs. body weight decreased with increasing temperature. The levels of SGR, FE, PRE and ERE varied slightly with temperature in individuals of 150–200 g, and the respective response surfaces showed a plateau within this range of body sizes independently of temperature. The temperature for maximum AFR was estimated to be 21.88 °C independently of body weight. Proximate composition and P / E ratio of Octopuses were not affected by temperature or body weight. It is concluded that temperature should be adjusted according to the body weight of O. vulgaris for optimizing the economic viability of rearing. Temperature should be high for small individuals (50–150 g) and should be reduced gradually in order for animals larger than 200 g to be reared at low temperature. Therefore, O. vulgaris should be reared in closed systems with temperature control.

  • combined effects of temperature and body weight on growth and protein utilization of the Common Octopus Octopus vulgaris
    Aquaculture, 2005
    Co-Authors: H. Miliou, Myrsini Fintikaki, Triantaphyllos Kountouris, G. Verriopoulos
    Abstract:

    Octopus vulgaris is considered a serious candidate for rearing, in terms of its biological and market potential: easy adaptation to captivity conditions, high growth rate and high market price. The aim of this study was to examine the combined effects of temperature and body weight on specific growth rate (SGR, % day � 1 ), absolute growth rate (AGR, g day � 1 ), absolute feeding rate (AFR, g day � 1 ), feed efficiency (FE, %), protein retention efficiency (PRE: [g protein gain g protein ingested � 1 ] � 100), energy retention efficiency (ERE: [kJ gain kJ ingested � 1 ] � 100), proximate composition and P/E ratio (protein/energy) of the Common Octopus. The experiments were performed in a closed system with controlled temperature (15, 20 and 25 8C). The Octopuses were fed on squids (Loligo vulgaris). In the multiple regression equations estimated for SGR, AGR, AFR, FE, PRE and ERE, the linear and quadratic effects of temperature, as well as the linear effects of body weight were significant. In addition, the interaction effects of temperature and body weight were significant for SGR, AGR, FE, PRE and ERE; the temperature for maximum response decreased with increasing size, being 25 8C for Octopuses of 50–150 g and 15 8C for animals of 200–600 g. The weight exponent in the relationships of these indices vs. body weight decreased with increasing temperature. The levels of SGR, FE, PRE and ERE varied slightly with temperature in individuals of 150–200 g, and the respective response surfaces showed a plateau within this range of body sizes independently of temperature. The temperature for maximum AFR was estimated to be 21.88 8C independently of body weight. Proximate composition and P/E ratio of Octopuses were not affected by temperature or body weight. It is concluded that temperature should be adjusted according to the body weight of O. vulgaris for optimizing the economic viability of rearing. Temperature should be high for small individuals (50–150 g) and should be reduced gradually in order for animals larger than 200 g to be reared at low temperature. Therefore, O. vulgaris should be reared in closed systems with temperature control. D 2005 Elsevier B.V. All rights reserved.

  • Effect of temperature on specific dynamic action in the Common Octopus, Octopus vulgaris (Cephalopoda)
    Marine Biology, 2004
    Co-Authors: Stelios Katsanevakis, N. Protopapas, H. Miliou, G. Verriopoulos
    Abstract:

    Feeding causes an increase of metabolic rate, which initially escalates rapidly, reaches a peak value and then gradually declines to the pre-feeding rate. This phenomenon, termed “specific dynamic action” (SDA), reflects the energy requirements of the behavioral, physiological and biochemical processes that constitute feeding. The effect of temperature on SDA of the Common Octopus, Octopus vulgaris, was evaluated, by measuring the temporal pattern of the oxygen consumption rates of Octopuses, after feeding, at two constant temperatures, 20°C and 28°C. At 20°C, the relative increase in the oxygen consumption rate after feeding (relative SDA) was significantly greater than at 28°C. The peak of the relative SDA occurred 1 h after feeding, and it was 64% at 20°C and 42% at 28°C. However, the SDA absolute peak, SDA duration (9.5 h) and SDA magnitude (the integrated postprandial increase in oxygen uptake) did not differ significantly between the two temperatures, indicating that the energetic cost of feeding was the same at both temperatures. The SDA response in O. vulgaris was much faster than it was in polar species, which have extended SDA responses due to low temperatures, and was also relatively fast in relation to the response in other temperate species, which is probably connected to the remarkably high growth rates of the species. A possible explanation of the observed summer migration of large Octopuses from shallow to deeper areas is given, based on the effect of temperature on the energetic requirements of Octopuses.

Benjamin Garcia Garcia - One of the best experts on this subject based on the ideXlab platform.

  • performance of marine lecithin supplemented feeds for the Common Octopus Octopus vulgaris ongrowing changes in proximate composition and lipid classes profile
    Fishes, 2019
    Co-Authors: Tania Rodriguezgonzalez, Jesus Cerezo Valverde, Benjamin Garcia Garcia
    Abstract:

    The development of artificial diets is considered vital for feasible cephalopods’ culture. Octopus vulgaris need a diet with a high protein content but also lipids are important at a lower quantity, as polar lipids and LC-PUFA are essential for development during early stages. In the present study the suitability of marine lecithin as a dietary supplement for O. vulgaris juveniles’ formulated feeds was tested for 56 days, assessing the performance, changes in proximate composition, and lipid classes’ profile in the digestive gland and carcass. Sixteen Octopus were fed one of two semi-moist feeds based on dry ingredients: either CALPRO (N = 4) as control or CALPRO-LM (N = 8); which differed from the first, due to the inclusion of 20 g/kg of marine lecithin as a phospholipid dietary supplement. Results showed that marine lecithin did not enhance feed intake, growth, protein or lipid incorporation, nutrients digestibility or feed efficiency. Moreover, at this level of inclusion, the composition of tissues (digestive gland and carcass) regarding macronutrients and lipid classes’ profile presented only a small amount of differences. In conclusion, the inclusion of marine lecithin did not promote beneficial effects on performance, making necessary further research related to the nutritional requirements of Common Octopus.

  • performance of raw material thermal treatment on formulated feeds for Common Octopus Octopus vulgaris ongrowing
    Aquaculture, 2015
    Co-Authors: Tania Rodriguezgonzalez, Jesus Cerezo Valverde, Antonio V Sykes, Benjamin Garcia Garcia
    Abstract:

    The Common Octopus (Octopus vulgaris) has aroused great interest in recent years as a new species for aquaculture. However, the inexistence of feeds with an adequate and balanced nutritional profile for all life stages has hampered O. vulgaris aquaculture development. In the present study, O. vulgaris juveniles were fed with one of two different diets, based on dried raw materials (22% gelatine, 10% egg yolk, 10% Boops boops, 5% Todarodes sagittatus, 5% Carcinus mediterraneus, 2% fish oil, 3% glucose, 3% starch and 40% water) and differing only on bogue (B. boops) thermal processing (either freeze-dried — FDb or bogue meal prepared with temperature below 60 °C — Mb). Growth, feed efficiency, digestibility and condition were assessed after 56 days of rearing. Data were used to determine growth, weight gain (Wg), absolute growth rate (AGR), specific growth rate (SGR), absolute feeding rate, absolute protein feeding rate (APFR), absolute lipid feeding rate (ALFR), specific feeding rate (SFR), feed efficiency (FE), feed conversion ratio (FCR), protein productive value (PPV), lipid productive value (LPV), digestive gland index (DGI) and apparent digestibility coefficients (ADC). Both diets were accepted, promoted growth and faeces production with 100% of survival. No significant differences were found in growth (SGR of 0.78 ± 0.19%BW·day− 1 for FDb and 0.85 ± 0.09%BW·day− 1 for Mb), feed efficiency (48.31 ± 9.70% and 39.22 ± 2.92% for FDb and Mb, respectively), PPV and LPV. Despite the similarity on FCR (P > 0.05), a higher ingestion was found on Mb group regarding AFR (P 0.05). The results revealed that dehydration of raw materials, performed under 60 °C (bogue-meal), had no effect on ingestion, digestibility, growth and survival when compared with the use of freeze-drying, which points out to the possible suitability of this thermal treatment for O. vulgaris feeds.

  • growth and mortality of Common Octopus Octopus vulgaris reared at different stocking densities in mediterranean offshore cages
    Aquaculture Research, 2009
    Co-Authors: Benjamin Garcia Garcia, Jesus Cerezo Valverde, Felipe Aguadogimenez, Jose Garcia Garcia, M D Hernandez
    Abstract:

    Four ongrowing cycles of Common Octopus (Octopus vulgaris), each with two stocking densities, were carried out in an offshore area in order to evaluate the effect of the following variables on growth (G, % body weight day−1) and mortality (M, % day−1): weight (W, 0.5–3.0 kg), temperature (T, 14–26 °C), stocking density (SD, 6–46 kg m−3), size dispersion, expressed as coefficient of variation (CV, 13–42%) and significant wave height (SWH: 0.4–1.2 m). The assays were performed in an 8 m3 stainless-steel floating cage divided into two compartments of 4 m3 each. For the range of temperatures considered (14–26 °C), G depended significantly on T and SWH, with maximum G values being obtained at 18.5 °C and with an important negative effect of SWH. M depended significantly on T, W and CV, mortality being minimal at 18 °C. The two other variables had an antagonistic effect, mortality increasing with greater size dispersion – suggesting that animals should be graded throughout the process – although the effect diminished as the sizes increased. The results point towards two alternatives for the commercial ongrowing of Octopus under the particular conditions of the present study: (A) two ongrowing cycles of 3.5 months to reach a final weight of 2.5 kg or (B) one 5-month cycle to reach a final weight of 3.5 kg.

  • optimal proportions of crabs and fish in diet for Common Octopus Octopus vulgaris ongrowing
    Aquaculture, 2006
    Co-Authors: Benjamin Garcia Garcia, Jesus Cerezo Valverde
    Abstract:

    Abstract Although the ongrowing of Octopus vulgaris shows great economic potential, to date, no commercially available diet exists so that trawled fish species of low economic value, which would otherwise be discarded, are used. Crustaceans form an important part of the diet of natural populations of O. vulgaris and, in captivity, they seem to be equally important for growth and survival. However, both the availability of crustaceans and their price seriously affect the profitability of O. vulgaris farming, particularly in the Mediterranean area. In the present study, we look at the optimal percentage of crabs and fish in the O. vulgaris diet, and different patterns of food distribution, taking into account biological and economic factors. For this, we used five experimental groups of Octopus (only males), each of which followed a distinct pattern of feeding, representing five different diets: (i) crab provided every day (Group C); (ii) crab provided on 3 consecutive days followed by bogue for 1 day (Group 3C1B); (iii) crab and bogue provided on alternate days (Group 1C1B); (iv) crab provided on 1 day, followed by bogue for 3 days (Group 1C3B); and (v) bogue provided every day (group B). According to the macronutrient composition of the diet supplied and the quantity of crab and/or bogue consumed by each individual Octopus, the mean macronutrient consumed each day was calculated, along with the gross energy and P/E ratio. The protein content of each diet was similar, 19–20% (wet substance), while the lipid content varied linearly from 0.79% in Group C to 6.11% in Group B. The optimal diet was reached in group 1C1B, with a growth rate of 1.98 ± 0.30% and a feeding efficiency of 39.35 ± 4.40%. The diet had a 2.65% lipid content and a P/E ratio of 31.68 g protein/MJ. However, from an economic point of view, the feeding strategy of group 1C3B seems to be the most adequate with a conversion index of 3 €/kg of Octopus produced.

  • influence of body weight and temperature on post prandial oxygen consumption of Common Octopus Octopus vulgaris
    Aquaculture, 2004
    Co-Authors: Jesus Cerezo Valverde, Benjamin Garcia Garcia
    Abstract:

    Abstract Feeding periods are accompanied by increased oxygen demand, and so, water flow or oxygen supply during culture should be suitably adjusted at such times. In this study, we determine the pattern of post-prandial oxygen consumption in Common Octopus ( Octopus vulgaris ) with body weights between 0.22 and 3.26 kg, at temperatures of 13.75–22.23 °C, which covers the normal ranges of weight and temperature used for its culture. The measurements were carried out over 3 days on single animals receiving one meal of crab to satiation. The oxygen consumption values were divided into routine ( M O 2routine ), post-prandial ( M O 2sda ), maximum peak ( M O 2peak ) and daily average between 0 and 24 h ( M O 2;0–24h ), 24 and 48 h ( M O 2;24–48h ) and 48 and 72 h ( M O 2;48–72h ) post-feeding. Furthermore, the time taken to reach M O 2 peak ( D peak ) and the duration of post-prandial oxygen consumption ( D sda ) were calculated. In all cases, M O 2;0–24h was higher than M O 2;24–48h and M O 2;48–72h ( P M O 2;24–48h and M O 2;48–72h ( P >0.05). This result suggests that feeding induces a significant transient short-term effect on oxygen consumption that does not usually last longer than 24 h. The different oxygen consumption categories fitted the equations ln M O 2routine =−0.726+0.702ln W +1.876ln T , ln M O 2sda =0.045+0.713ln W +1.769ln T , ln M O 2peak =0.152+0.716ln W +1.767ln T and ln M O 2;0–24h =0.220+0.716ln P +1.688ln T to a statistically significant degree ( P D peak and D sda showed values of 6–16 h (9.98±2.49 h) and 15–28 h (19.79±3.83 h), respectively, both being independent of weight and temperature ( P >0.05). Finally, the influence of other factors such as daily activity patterns or sex on oxygen consumption were analysed.

Juan Carlos Navarro - One of the best experts on this subject based on the ideXlab platform.

  • dietary effect on the proteome of the Common Octopus Octopus vulgaris paralarvae
    Frontiers in Physiology, 2017
    Co-Authors: Inmaculada Varó, Oscar Monroig, Francisco Hontoria, E Almansa, G Cardenete, Jose Iglesias, J J Otero, Juan Carlos Navarro
    Abstract:

    Nowadays, the Common Octopus (Octopus vulgaris) culture is hampered by massive mortalities occurring during early life-cycle stages (paralarvae). Despite the causes of the high paralarvae mortality are not yet well defined and understood, the nutritional stress caused by inadequate diets is pointed out as one of the main factors. In this study the effects of diet on paralarvae is analyzed through a proteomic approach, to search for novel biomarkers of nutritional stress. A total of 43 proteins showing differential expression in the different conditions studied have been identified. The analysis highlights proteins related with the carbohydrate metabolism: glyceraldehyde-3-phosphate-dedydrogenase (GAPDH), triosephosphate isomerase; other ways of energetic metabolism: NADP+-specific isocitrate dehydrogenase, arginine kinase; detoxification: glutathione-S-transferase (GST); stress: heat shock proteins (HSP70); structural constituent of eye lens: S-crystallin 3; and cytoskeleton: actin, actin-beta/gamma1, beta actin. These results allow defining characteristic proteomes of paralarvae depending on the diet; as well as the use of several of these proteins as novel biomarkers to evaluate their welfare linked to nutritional stress. Notably, the changes of proteins like S-crystallin 3, arginine kinase and NAD+ specific isocitrate dehydrogenase, may be related to fed versus starving paralarvae, particularly in the first 4 days of development.

  • enrichment of artemia metanauplii in phospholipids and essential fatty acids as a diet for Common Octopus Octopus vulgaris paralarvae
    Aquaculture Nutrition, 2013
    Co-Authors: Diana Guinot, Oscar Monroig, Juan Carlos Navarro, Inmaculada Varó, Francisco Amat, Francisco Hontoria
    Abstract:

    Highly unsaturated fatty acids (HUFA), like the eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids and polar lipids (essentially phospholipids, PL) have been identified as essential nutrients for Common Octopus (Octopus vulgaris) paralarvae. However, they are not available in sufficient amounts in live preys as Artemia, making necessary a supplementation of these nutrients previous use. A commercial emulsion, soya liposomes, and marine and soya lecithins were used to supply HUFA and PL to Artemia metanauplii, those being regarded as suitable size preys for Octopus paralarvae. Our results prove that a simultaneous enrichment in HUFA and PL is possible using enrichment diets combining HUFA- and PL-rich products in short-term (4 h) incubations. Particularly interesting was the enrichment efficiency shown by the marine lecithin, which enabled the enhancement of the PL fraction of Artemia metanauplii and, importantly, also their HUFA with a remarkable 13% DHA of total fatty acids. Marine lecithin arises as a novel enrichment diet for Artemia and more effective than some commercial products currently used in hatcheries worldwide.

  • biosynthesis of essential fatty acids in Octopus vulgaris cuvier 1797 molecular cloning functional characterisation and tissue distribution of a fatty acyl elongase
    Aquaculture, 2012
    Co-Authors: Oscar Monroig, Douglas R Tocher, Diana Guinot, Francisco Hontoria, Juan Carlos Navarro
    Abstract:

    Polyunsaturated fatty acids (PUFAs) have been identified as key nutrients for the Common Octopus (Octopus vulgaris), particularly for its early life-cycle stages (paralarvae). Our overarching aim is to identify the dietary essential fatty acid (FA) for Octopus paralarvae through characterisation of the enzymes of endogenous PUFA biosynthetic pathways. Here we report on the molecular cloning and functional characterisation of a cDNA encoding a putative elongase of very long-chain fatty acids (Elovl), a critical enzyme that catalyses the elongation of FA including PUFA. Our results suggest that the Octopus Elovl is phylogenetically related to Elovl5 and Elovl2, two elongases with demonstrated roles in PUFA biosynthesis in vertebrates. Further evidence supporting a role of the Octopus Elovl in PUFA biosynthesis was provided through functional characterisation of its activity in yeast. It was confirmed that expression of the Octopus Elovl conferred on yeast the ability to elongate some C18 and C20 PUFAs, while C22 PUFA substrates remained unmodified. Therefore, the substrate specificities exhibited by the Octopus elongase were consistent with those of vertebrate Elovl5. Interestingly, the Octopus Elovl elongated n − 6 PUFA substrates more efficiently than their homologous n − 3 substrates, suggesting that n − 6 PUFA may have particular biological significance in O. vulgaris. Finally, we investigated the potential role of the newly cloned Elovl in the biosynthesis of non-methylene-interrupted FA, compounds typically found in marine invertebrates and confirmed to be also present in the Common Octopus.

  • Biosynthesis of polyunsaturated fatty acids in the Common Octopus, Octopus vulgaris
    2012
    Co-Authors: Douglas R Tocher, Oscar Monroig, Juan Carlos Navarro, Francisco Hontoria, Inmaculada Varó, Francesc Alemany
    Abstract:

    Trabajo presentado en el 15th International Symposium on Fish Nutrition and Feeding (ISFNF 2012), celebrado en Molde (Noruega), del 4 al 7 de junio de 2012

H. Miliou - One of the best experts on this subject based on the ideXlab platform.

  • fatty acid composition of the Common Octopus Octopus vulgaris in relation to rearing temperature and body weight
    Aquaculture, 2006
    Co-Authors: H. Miliou, Myrsini Fintikaki, Marios Tzitzinakis, Triantaphyllos Kountouris, G. Verriopoulos
    Abstract:

    Abstract Octopus vulgaris is considered a candidate for aquaculture and its growth performance is dependent upon temperature and body weight. The aim of this study was to investigate the effects of temperature on the fatty acid composition of O. vulgaris in relation to body weight (60–663 g). The experiments were performed in a closed seawater system with controlled temperature (15, 20 and 25 °C). The Octopuses were fed on squid ( Loligo vulgaris ). O. vulgaris showed a high content of polyunsaturated fatty acids (51.32–57.62% total fatty acids), particularly n  − 3 highly unsaturated acids (38.01–52.73% total fatty acids). At each temperature, the proportion of some fatty acids was highly ( P n  − 9, 18:1 n  − 7, 18:2 n  − 6, 20:4 n  − 6, 22:4 n  − 6 and 22:5 n  − 6 decreased, while 20:5 n  − 3 (EPA) and 22:6 n  − 3 (DHA) increased, with increasing body weight at 20 and 25 °C. The opposite was observed at 15 °C. Total polyunsaturated and n  − 3 highly unsaturated fatty acids (HUFA) decreased in larger Octopuses at 15 °C, as well as in smaller Octopuses at 25 °C, whereas total saturated, monounsaturated and n  − 6 HUFA increased. Thus, total unsaturated fatty acids showed a relatively small variation (60.53–63.96% total fatty acids) and the mean unsaturation index was similar at 15 and 25 °C. Arachidonic acid (2.4–9.6% total fatty acids) was inversely related to EPA and DHA, and positively to 18:2 n  − 6, 22:4 n  − 6 and 22:5 n  − 6. It is noted that arachidonic acid is not an essential fatty acid for the Common Octopus. It is concluded that the fatty acid composition of O. vulgaris was influenced by temperature and body weight, but with an n  − 3/ n  − 6 ratio of more than 3 and a DHA/EPA ratio of more than 1.5. The Common Octopus could be an excellent source of arachidonic acid, containing sufficient n  − 3 HUFA levels, in low temperatures for large individuals and in warm temperatures for small ones.

  • combined effects of temperature and body weight on growth and protein utilization of the Common Octopus Octopus vulgaris
    Aquaculture, 2005
    Co-Authors: H. Miliou, Myrsini Fintikaki, Triantaphyllos Kountouris, G. Verriopoulos
    Abstract:

    Abstract Octopus vulgaris is considered a serious candidate for rearing, in terms of its biological and market potential: easy adaptation to captivity conditions, high growth rate and high market price. The aim of this study was to examine the combined effects of temperature and body weight on specific growth rate (SGR, % day − 1 ), absolute growth rate (AGR, g day − 1 ), absolute feeding rate (AFR, g day − 1 ), feed efficiency (FE, %), protein retention efficiency (PRE: [g protein gain g protein ingested − 1 ] × 100), energy retention efficiency (ERE : [kJ gain kJ ingested − 1 ] × 100), proximate composition and P / E ratio (protein/energy) of the Common Octopus. The experiments were performed in a closed system with controlled temperature (15, 20 and 25 °C). The Octopuses were fed on squids ( Loligo vulgaris ). In the multiple regression equations estimated for SGR, AGR, AFR, FE, PRE and ERE , the linear and quadratic effects of temperature, as well as the linear effects of body weight were significant. In addition, the interaction effects of temperature and body weight were significant for SGR, AGR, FE, PRE and ERE; the temperature for maximum response decreased with increasing size, being 25 °C for Octopuses of 50–150 g and 15 °C for animals of 200–600 g. The weight exponent in the relationships of these indices vs. body weight decreased with increasing temperature. The levels of SGR, FE, PRE and ERE varied slightly with temperature in individuals of 150–200 g, and the respective response surfaces showed a plateau within this range of body sizes independently of temperature. The temperature for maximum AFR was estimated to be 21.88 °C independently of body weight. Proximate composition and P / E ratio of Octopuses were not affected by temperature or body weight. It is concluded that temperature should be adjusted according to the body weight of O. vulgaris for optimizing the economic viability of rearing. Temperature should be high for small individuals (50–150 g) and should be reduced gradually in order for animals larger than 200 g to be reared at low temperature. Therefore, O. vulgaris should be reared in closed systems with temperature control.

  • combined effects of temperature and body weight on growth and protein utilization of the Common Octopus Octopus vulgaris
    Aquaculture, 2005
    Co-Authors: H. Miliou, Myrsini Fintikaki, Triantaphyllos Kountouris, G. Verriopoulos
    Abstract:

    Octopus vulgaris is considered a serious candidate for rearing, in terms of its biological and market potential: easy adaptation to captivity conditions, high growth rate and high market price. The aim of this study was to examine the combined effects of temperature and body weight on specific growth rate (SGR, % day � 1 ), absolute growth rate (AGR, g day � 1 ), absolute feeding rate (AFR, g day � 1 ), feed efficiency (FE, %), protein retention efficiency (PRE: [g protein gain g protein ingested � 1 ] � 100), energy retention efficiency (ERE: [kJ gain kJ ingested � 1 ] � 100), proximate composition and P/E ratio (protein/energy) of the Common Octopus. The experiments were performed in a closed system with controlled temperature (15, 20 and 25 8C). The Octopuses were fed on squids (Loligo vulgaris). In the multiple regression equations estimated for SGR, AGR, AFR, FE, PRE and ERE, the linear and quadratic effects of temperature, as well as the linear effects of body weight were significant. In addition, the interaction effects of temperature and body weight were significant for SGR, AGR, FE, PRE and ERE; the temperature for maximum response decreased with increasing size, being 25 8C for Octopuses of 50–150 g and 15 8C for animals of 200–600 g. The weight exponent in the relationships of these indices vs. body weight decreased with increasing temperature. The levels of SGR, FE, PRE and ERE varied slightly with temperature in individuals of 150–200 g, and the respective response surfaces showed a plateau within this range of body sizes independently of temperature. The temperature for maximum AFR was estimated to be 21.88 8C independently of body weight. Proximate composition and P/E ratio of Octopuses were not affected by temperature or body weight. It is concluded that temperature should be adjusted according to the body weight of O. vulgaris for optimizing the economic viability of rearing. Temperature should be high for small individuals (50–150 g) and should be reduced gradually in order for animals larger than 200 g to be reared at low temperature. Therefore, O. vulgaris should be reared in closed systems with temperature control. D 2005 Elsevier B.V. All rights reserved.

  • Effect of temperature on specific dynamic action in the Common Octopus, Octopus vulgaris (Cephalopoda)
    Marine Biology, 2004
    Co-Authors: Stelios Katsanevakis, N. Protopapas, H. Miliou, G. Verriopoulos
    Abstract:

    Feeding causes an increase of metabolic rate, which initially escalates rapidly, reaches a peak value and then gradually declines to the pre-feeding rate. This phenomenon, termed “specific dynamic action” (SDA), reflects the energy requirements of the behavioral, physiological and biochemical processes that constitute feeding. The effect of temperature on SDA of the Common Octopus, Octopus vulgaris, was evaluated, by measuring the temporal pattern of the oxygen consumption rates of Octopuses, after feeding, at two constant temperatures, 20°C and 28°C. At 20°C, the relative increase in the oxygen consumption rate after feeding (relative SDA) was significantly greater than at 28°C. The peak of the relative SDA occurred 1 h after feeding, and it was 64% at 20°C and 42% at 28°C. However, the SDA absolute peak, SDA duration (9.5 h) and SDA magnitude (the integrated postprandial increase in oxygen uptake) did not differ significantly between the two temperatures, indicating that the energetic cost of feeding was the same at both temperatures. The SDA response in O. vulgaris was much faster than it was in polar species, which have extended SDA responses due to low temperatures, and was also relatively fast in relation to the response in other temperate species, which is probably connected to the remarkably high growth rates of the species. A possible explanation of the observed summer migration of large Octopuses from shallow to deeper areas is given, based on the effect of temperature on the energetic requirements of Octopuses.

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  • dietary effect on the proteome of the Common Octopus Octopus vulgaris paralarvae
    Frontiers in Physiology, 2017
    Co-Authors: Inmaculada Varó, Oscar Monroig, Francisco Hontoria, E Almansa, G Cardenete, Jose Iglesias, J J Otero, Juan Carlos Navarro
    Abstract:

    Nowadays, the Common Octopus (Octopus vulgaris) culture is hampered by massive mortalities occurring during early life-cycle stages (paralarvae). Despite the causes of the high paralarvae mortality are not yet well defined and understood, the nutritional stress caused by inadequate diets is pointed out as one of the main factors. In this study the effects of diet on paralarvae is analyzed through a proteomic approach, to search for novel biomarkers of nutritional stress. A total of 43 proteins showing differential expression in the different conditions studied have been identified. The analysis highlights proteins related with the carbohydrate metabolism: glyceraldehyde-3-phosphate-dedydrogenase (GAPDH), triosephosphate isomerase; other ways of energetic metabolism: NADP+-specific isocitrate dehydrogenase, arginine kinase; detoxification: glutathione-S-transferase (GST); stress: heat shock proteins (HSP70); structural constituent of eye lens: S-crystallin 3; and cytoskeleton: actin, actin-beta/gamma1, beta actin. These results allow defining characteristic proteomes of paralarvae depending on the diet; as well as the use of several of these proteins as novel biomarkers to evaluate their welfare linked to nutritional stress. Notably, the changes of proteins like S-crystallin 3, arginine kinase and NAD+ specific isocitrate dehydrogenase, may be related to fed versus starving paralarvae, particularly in the first 4 days of development.

  • Dietary Effect on the Proteome of the Common Octopus (Octopus vulgaris) Paralarvae
    Frontiers Media S.A., 2017
    Co-Authors: Inmaculada Varó, Oscar Monroig, Francisco Hontoria, G Cardenete, Jose Iglesias, J J Otero, Eduardo Almansa, Juan C. Navarro
    Abstract:

    Nowadays, the Common Octopus (Octopus vulgaris) culture is hampered by massive mortalities occurring during early life-cycle stages (paralarvae). Despite the causes of the high paralarvae mortality are not yet well-defined and understood, the nutritional stress caused by inadequate diets is pointed out as one of the main factors. In this study, the effects of diet on paralarvae is analyzed through a proteomic approach, to search for novel biomarkers of nutritional stress. A total of 43 proteins showing differential expression in the different conditions studied have been identified. The analysis highlights proteins related with the carbohydrate metabolism: glyceraldehyde-3-phosphate-dedydrogenase (GAPDH), triosephosphate isomerase; other ways of energetic metabolism: NADP+-specific isocitrate dehydrogenase, arginine kinase; detoxification: glutathione-S-transferase (GST); stress: heat shock proteins (HSP70); structural constituent of eye lens: S-crystallin 3; and cytoskeleton: actin, actin-beta/gamma1, beta actin. These results allow defining characteristic proteomes of paralarvae depending on the diet; as well as the use of several of these proteins as novel biomarkers to evaluate their welfare linked to nutritional stress. Notably, the changes of proteins like S-crystallin 3, arginine kinase and NAD+ specific isocitrate dehydrogenase, may be related to fed vs. starving paralarvae, particularly in the first 4 days of development

  • enrichment of artemia metanauplii in phospholipids and essential fatty acids as a diet for Common Octopus Octopus vulgaris paralarvae
    Aquaculture Nutrition, 2013
    Co-Authors: Diana Guinot, Oscar Monroig, Juan Carlos Navarro, Inmaculada Varó, Francisco Amat, Francisco Hontoria
    Abstract:

    Highly unsaturated fatty acids (HUFA), like the eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids and polar lipids (essentially phospholipids, PL) have been identified as essential nutrients for Common Octopus (Octopus vulgaris) paralarvae. However, they are not available in sufficient amounts in live preys as Artemia, making necessary a supplementation of these nutrients previous use. A commercial emulsion, soya liposomes, and marine and soya lecithins were used to supply HUFA and PL to Artemia metanauplii, those being regarded as suitable size preys for Octopus paralarvae. Our results prove that a simultaneous enrichment in HUFA and PL is possible using enrichment diets combining HUFA- and PL-rich products in short-term (4 h) incubations. Particularly interesting was the enrichment efficiency shown by the marine lecithin, which enabled the enhancement of the PL fraction of Artemia metanauplii and, importantly, also their HUFA with a remarkable 13% DHA of total fatty acids. Marine lecithin arises as a novel enrichment diet for Artemia and more effective than some commercial products currently used in hatcheries worldwide.

  • biosynthesis of essential fatty acids in Octopus vulgaris cuvier 1797 molecular cloning functional characterisation and tissue distribution of a fatty acyl elongase
    Aquaculture, 2012
    Co-Authors: Oscar Monroig, Douglas R Tocher, Diana Guinot, Francisco Hontoria, Juan Carlos Navarro
    Abstract:

    Polyunsaturated fatty acids (PUFAs) have been identified as key nutrients for the Common Octopus (Octopus vulgaris), particularly for its early life-cycle stages (paralarvae). Our overarching aim is to identify the dietary essential fatty acid (FA) for Octopus paralarvae through characterisation of the enzymes of endogenous PUFA biosynthetic pathways. Here we report on the molecular cloning and functional characterisation of a cDNA encoding a putative elongase of very long-chain fatty acids (Elovl), a critical enzyme that catalyses the elongation of FA including PUFA. Our results suggest that the Octopus Elovl is phylogenetically related to Elovl5 and Elovl2, two elongases with demonstrated roles in PUFA biosynthesis in vertebrates. Further evidence supporting a role of the Octopus Elovl in PUFA biosynthesis was provided through functional characterisation of its activity in yeast. It was confirmed that expression of the Octopus Elovl conferred on yeast the ability to elongate some C18 and C20 PUFAs, while C22 PUFA substrates remained unmodified. Therefore, the substrate specificities exhibited by the Octopus elongase were consistent with those of vertebrate Elovl5. Interestingly, the Octopus Elovl elongated n − 6 PUFA substrates more efficiently than their homologous n − 3 substrates, suggesting that n − 6 PUFA may have particular biological significance in O. vulgaris. Finally, we investigated the potential role of the newly cloned Elovl in the biosynthesis of non-methylene-interrupted FA, compounds typically found in marine invertebrates and confirmed to be also present in the Common Octopus.

  • Biosynthesis of polyunsaturated fatty acids in the Common Octopus, Octopus vulgaris
    2012
    Co-Authors: Douglas R Tocher, Oscar Monroig, Juan Carlos Navarro, Francisco Hontoria, Inmaculada Varó, Francesc Alemany
    Abstract:

    Trabajo presentado en el 15th International Symposium on Fish Nutrition and Feeding (ISFNF 2012), celebrado en Molde (Noruega), del 4 al 7 de junio de 2012