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[EN] The apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, and amino acids in fish, krill, squid, meat, defatted krill, soybean, wheat gluten, wheat, camilina, pea, sunflower, and fava bean meals were determined for juvenile Seriola dumerili. The results showed that the ADC of dry matter for yellowtail ranged from 57.7 to 87.2% for animal ingredients and from 42.2 to 82.2% for plant ingredients. An ADC of protein exceeding 90% was observed in fishmeal, while camilina meal and fava bean meal presented the lowest values. Pea meal presented the lowest lipid ADC (83.5%). The availabilities were generally higher in animal ingredients than those in vegetal ones. Except camilina and fava bean meal, the other ingredients appear to be favorable for S. dumerili diets, especially the ones from animal sources. Lower case chemical score values (minimum value from amino acid ratios [AARs]) were obtained in some vegetal ingredients (14¿18%), while the highest ones were observed in marine ingredients (69¿88%). According to Oser's Index, the most balanced protein for yellowtail with regard to essential amino acids was in krill, defatted krill, and fishmeal (92¿96%). So, animal sources are suitable as protein ingredients, but they could be enhanced through some essential amino acid supplementation., This project was financed by the “Ministerio de Ciencia e Innovación” (reference AGL2011-30547-C03).

[EN] The objective of this study was to evaluate the effect of fish meal replacement with a mixture of plant, and animal protein supplemented with a commercial nucleotide NucleofomeFish (TM), on growth, feed utilization, whole-body composition, biometric indices; liver mitochondrial enzyme activities, selected gene expression and influence on the gut micmbiome of gilthead seabream, Sparus aurata. Six hundred and thirty gilthead seabream with an average initial body weight of 0.358 +/- 0.002 g/fish, were used. Six experimental diets were formulated to be isonitrogenous, 45% crude protein (CP) and isocaloric 20 MJ/kg gross energy (GE). The control diet (Dl) contained 25% of fish meal (FM25) and had no NucleoforceFish (TM) added (FM25/0), diets 2-3 contained FM at a level of 25% and supplemented with 250 (FM25/250) and 500 (FM25/500) mg/kg NucleoforceFish (TM), respectively. Diets 4-6 were a non-fishmeal formulation and had no NucleoforceFish (TM), (diet 4, FM0/0), 0%FM with 250mg/kg NucleoforceFish (TM) (diet 5, FM0/250), and 0%FM with 500mg/kg NucleofomeFish (TM) (diet 6, FM0/500). The results revealed that dietary nucleotides supplemented at 250mg/kg or 500mg/kg enhanced final body weight, weight gain, and specific growth rate of seabream either with dietary level of 25% FM diet (FM25) or non-fishmeal diet (FM0). All mitochondrial liver complex enzyme activities were recorded as having a significant positive response to the nucleotide dietary supplement. Gilthead seabream fingerlings fed FM0/250 diet for 150 days had significantly elevated liver mitochondrial enzyme (Complex III, Complex IV, Complex I and II) activities. In addition, gilthead seabream fed FM(0/500 )had significantly increased the gene expression of TCR-B and IL1-B, while fish fed FM25/250 increased significantly the gene expression of IGF1, while fish fed FM(25/500 )increased significantly the gene expression of Hepcidin (Hep) and the iron homeostasis hormone. There was a marked influence on specific bacteria comprising the gut microbiome namely Photobacterium; damselae; Vibrio anguillarum; Lactobacillus plantarum; Lactobacillus Enterococcus faecium subtilis. It can be concluded that FM25/250 and FM25/500 diets are expressing the best result, which explains that FM must be in the feed of gilthead seabream, and addition of NucleoforceFish (TM) at 250 mg/kg feed may further increase the performance.

[EN] Seabass is one of the leading aquaculture species in Europe. Sensory analysis is essential for new product development. This research focused on establishing and differentiating the opinion of consumers about seabass quality obtained with organic feeding. Fish were fed for 196 days with four treatments (a control diet with 30% fishmeal and three diets with different levels of fishmeal supplemented with organic vegetable ingredients: 25%, 30% and 35%). Experimental diets were compared with commercial samples from the retail industry that were considered as "adequate quality for fish ". Two sensory analyses were carried out, check-all-that-apply (CATA) to obtain feedback on consumers' characterization towards a different type of fish evaluated and projective mapping (PM) to measure the similarity among a set of products and establish a comparison between results provided by both methods. According to the CATA results, white color, softness, meaty taste and juicy texture were considered relevant attributes, also showing a good relationship with an adequate cooked fish description. A penalty analysis confirmed that the previous characteristics were considered essential while fibrous was an undesirable attribute. The projective mapping showed a similar sensory configuration to the CATA, corroborating these findings that showed that commercial fish were placed in a position away from the rest of the treatments, and the organic diet with a higher level of fishmeal (35%) was the most distant from the control diet., This Project was subsidized by the Biodiversity Foundation 1-2020, within the framework of the Pleamar Program, co-financed by the FEMP.

[EN] Triploid, sterile Atlantic salmon (Salmo salar) could make a contribution to the development of the farming industry, but uncertainties about the performance and welfare of triploids have limited their adoption by farmers. In this study, we compared the ontogeny of digestive tract morphology and enzyme activities (pepsin, trypsin, chymotrypsin, alkaline phosphatase and aminopeptidase) of diploid and triploid Atlantic salmon. Fish were fed diets based on fishmeal (STD) or a mix of fishmeal and hydrolysed fish proteins (HFM) whilst being reared at low temperature from start-feeding to completion of the parr-smolt transformation. Fish weights for each ploidy and feed combination were used to calculate thermal growth coefficients (TGCs) that spanned this developmental period, and the data were used to examine possible relationships between enzyme activities and growth. At the end of the experiment, faeces were collected and analyzed to determine the apparent digestibility coefficients (ADCs) of the dietary amino acids (AAs). Digestive tract histo-morphology did not differ substantially between ploidies and generally reflected organ maturation and functionality. There were no consistent differences in proteolytic enzyme activities resulting from the inclusion of HFM in the diet, nor was there improved digestibility and AA bioavailability of the HFM feed in either diploid or triploid fish. The triploid salmon had lower ADCs than diploids for most essential and non-essential AAs in both diets (STD and HFM), but without there being any indication of lower intestinal protease activity in triploid fish. When trypsin-to-chymotrypsin activity and trypsin and alkaline phosphatase (ALP) ratios (T:C and T:ALP, respectively) were considered in combination with growth data (TGC) low T:C and T:ALP values coincided with times of reduced fish growth, and vice versa, suggesting that T:C and T:ALP may be used to predict recent growth history and possible growth potential., This work was supported by the Norwegian Research Council, Regional Research Fund-RFF-NORD -https://www. regionaleforskningsfond.no/ -(Grant no. 248028, VP at Nofima as project coordinator) and the Norwegian College of Fishery Science, University of Tromsø, (UiT) the Arctic University of Norway. The funder provided support in the form of salary for one author [VP] but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of this and other authors are articulated in the "author contributions" section. Publication charges for the article were provided by the Open Access publication fund of UiT, the Arctic University of Norway.

The interaction between diet and intestinal health has been widely discussed, although in vivo approaches have reported limitations. The intestine explant culture system developed provides an advantage since it reduces the number of experimental fish and increases the time of incubation compared to similar methods, becoming a valuable tool in the study of the interactions between pathogenic bacteria, rearing conditions, or dietary components and fish gut immune response. The objective of this study was to determine the influence of the total substitution of fish meal by plants on the immune intestinal status of seabream using an ex vivo bacterial challenge. For this aim, two growth stages of fish were assayed (12 g): phase I (90 days), up to 68 g, and phase II (305 days), up to 250 g. Additionally, in phase II, the effects of long term and short term exposure (15 days) to a plant protein (PP) diet were determined. PP diet altered the mucosal immune homeostasis, the younger fish being more sensitive, and the intestine from fish fed short-term plant diets showed a higher immune response than with long-term feeding. Vibrio alginolyticus (V. alginolyticus) triggered the highest immune and inflammatory response, while COX-2 expression was significantly induced by Photobacterium damselae subsp. Piscicida (P. damselae subsp. Piscicida), showing a positive high correlation between the pro-inflammatory genes encoding interleukin 1β (IL1-β), interleukin 6 (IL-6) and cyclooxygenase 2(COX-2)., The research was supported by a grant financed by the Spanish Ministerio de Economía y Competitividad AGL2015-70487-P and Generalitat Valenciana, IDIFEDER/2020/029

[EN] The search for new sustainable aquafeeds for the species with greater economic importance, such as the gilthead sea bream in Europe, is one of the main challenges in the aquaculture sector. The present work tested fishmeal replacement by a mixture of plant meals at different levels, as well as the use of marine by-products with attractant properties and high-quality protein in high plant protein diets. In order to do that, effects on growth and biometric parameters, digestibility, amino acid retention, excreted ammonia and proteases and amylase activity were assessed, using six different diets: FM100 (100% of protein provided by fishmeal), FM50 (50% of replacement), FM25 (75% of replacement) and FM0 (100% of replacement), but also FM25+ (75% of replacement and 15% of squid and krill meal inclusion), and FM0+ (100% of replacement and 15% of squid and krill meal inclusion). In group FM0, a clear impact of dietary changes was observed on growth, survival and ammonia excretion. Amino acid retention in group FM0+ was also significantly affected, which can be explained by the limited content of certain amino acids in this diet. On the other hand, no significant differences were observed in most biometric parameters or in enzyme activity. In conclusion, complete fishmeal replacement can be achieved by using a mixture of plant-based sources, but supplementation with complementary marine ingredients can prevent detrimental effects on growth, survival, nutritional parameters and protein metabolism., This work was supported by the Vicerrectorat d'Investigacio, Innovacio i Transferencia of the Universitat Politecnica de Valencia, within the project Aquaculture feed without fishmeal (SP20120603). URLs of funder: http://www.upv.es/entidades/VIIT/info/indexnormalc.htm. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Las muestras de animales plagas fueron colectadas, secadas y molidas. Estas fueron analizadas para determinar su contenido en proteína, cenizas y aminoácidos. Los análisis bromatológicos mostraron que Achatina fulica y Pieris brassica, contienen más proteína bruta, (PB) (779.2 y 812.2 g/kg) en comparación a Phyllophaga spp. y Spodoptera frugierda (432. 5 y 445.7 g/kg). Comparando el perfil de aminoácidos, A. fulica y P. brassica obtuvieron los niveles más altos en la mayoría de los amino ácidos esenciales (AAE) que la torta de soya y en el caso de A. fulica, éste exhibió valores más altos que la harina de pescado en arginina, cisteina, glicina, serina y tirosina. Observando la relación de AAE/AANE (amino ácidos no esenciales) en las harinas, sólo S. frugiperda presentó valores similares a la harina de pescado (0.85). Todas las harinas de animales plagas presentaron una reducción en la cuantificación de amino ácidos en relación con los valores de PB obtenidos por el método de Kjeldahl, esta reducción se encontraba entre 28.6 y 38.0%. Esta disminución podría deberse a la combinación entre la proteína y la quitina que se encuentran en el cuerpo de los insectos. A pesar de esta reducción la cuantificación de amino ácidos de los animales plagas podría ser una buena alternativa para su uso en la alimentación de monogástricos, especialmente para peces y crustáceos.

[EN] A digestibility trial was conducted to evaluate the effect of fishmeal (FM) replacement with meat and bone meal on diets digestibility, digestive enzymes activity, and microbiota modulation in gilthead seabream (Sparus aurata) juveniles fed diets (45% CP; 20% CL) including 0, 50, and 75% of protein from MBM (diets MBM0; MBM50; MBM75). The ADC of protein was high and unaffected by dietary MBM level, whereas the ADC of energy was higher with diet MBM50 than with MBM0. The ADC of essential amino acids was also high and not affected by diet composition, except for the ADC of phenylalanine and tyrosine, which were lower in diet MBM75 than in the other diets. Pepsin, trypsin, chymotrypsin, lipase, and total alkaline proteases activities were all unaffected by diet composition. Dietary inclusion of MBM modulated gastrointestinal tract microbiota, decreasing the average number of operational taxonomic units and microbial richness. Dietary MBM inclusion promoted an increase of Vibrio, Bacillus, and Mycobacterium genera, whereas colonization by Staphylococcus and Corynebacterium decreased. Overall, present results indicate that up to 75% of FM protein can be replaced by MBM protein in diets for gilthead seabream juveniles without major adverse effects on diet digestibility and digestive function. However, gastrointestinal microbiota was modulated, and further research should be conducted to evaluate the impact of gastrointestinal microbiota modulation on immune and health status of gilthead seabream., This research was partially supported by the Strategic Funding UID/Multi/04423/2013 through national funds provided by FCT - Foundation for Science and Technology and European Regional Development Fund (ERDF), in the framework of the programme PT2020. C.R. Serra was supported by grant SFRH/BPD/101038/2014, from FCT.

A trial was conducted to evaluate fish meal (FM) replacement with meat and bone meal (MBM; 53% CP, 15% CL, 27% Ash) in diets for gilthead seabream (Sparus aurata) juveniles. Three extruded experimental diets were formulated (45% CP; 20% CL) to include 0, 50 and 75% of protein from MBM (diets MBM0; MBM50; MBM75). Triplicate groups of seabream (IBW = 25 g) were fed these diets to satiety for 12 weeks. Growth performance and feed efficiency were similar with the diets MBM0 and MBM50, but were lower with diet MBM75, while the opposite was true for feed intake. Whole-body composition was not affected by diets composition except for crude lipid and energy content, which were lower with the diet MBM75. Protein and essential amino acids retention were unaffected by diet composition, while energy retention was lower with the diet MBM75. In terms of economic efficiency, diets with MBM resulted in a lower production costs, with the lowest economic conversion ratio (€ kg− 1 fish produced) being obtained for the MBM diets while the maximum economic profit (€ kg fish− 1) was obtained for diet MBM50. Overall, up to 50% of FM protein can be replaced by MBM protein in diets for gilthead seabream juveniles, without compromising growth performance, feed utilization, and nutrient retention. Statement of relevance Replacing 50% of fishmeal protein improved economic return.

[EN] An 84-day trial was performed to assess the use of alternative protein sources in Seriola dumerili. Three diets were used, FM100 diet, as a control diet without fishmeal substitution, and FM66 and FM33 diets with a fishmeal replacement of 330 g/kg and 660 g/kg, respectively. At the end of experiment, fish fed the FM66 diet showed the no differences in growth, nutritional parameters and fatty acid composition. Heavy metals present some differences but are always lower than risk levels. In sensory analysis, differences between diets appeared in pH and color, and also in some texture parameters between FM33 and the other two diets. No differences appeared between diets related to flavor. In summary, long periods of feeding with high fish meal substitution diets, affects Seriola dumerili growth; despite this the quality of the fillet was not affected even with a 66 % of substitution., This project was financed by "Generalitat Valenciana. Ayudas para grupos de investigacion consolidables."

In this work the effect of partial or total replacement of fishmeal by plant protein sources and krill and squid meal on growth performance and shelf-life of gilthead sea bream was evaluated. Plant protein dietswith 50 g kg&minus, 1 of krill and 100 g kg&minus, 1 of squid were supplemented with synthetic amino acidsand at the end of the growing period weight showed no significant differences. The spoilage process of the fish was followed by physicochemical and microbiological measurements together with a colorimetric sensor array (CSA) specially designed for that purpose. The changes in the physicochemical parameters and microbial growth showed that shelf-life of samples were in all cases lower than ninedays. The CSA was not able to show significant differences between both diets, confirming the physicochemical and microbiological results. The fact that the type of feed had no effect on the freshness parameters studied demonstrates that total fishmeal replacement with plant protein blends in the proportions used in this work could be an excellent alternative for feed formulation in aquaculture.

[EN] The digestive tract, particularly the intestine, represents one of the main sites of interactions with the environment, playing the gut mucosa a crucial role in the digestion and absorption of nutrients, and in the immune defence. Previous researches have proven that the fishmeal replacement by plant sources could have an impact on the intestinal status at both digestive and immune level, compromising relevant productive parameters, such as feed efficiency, growth or survival. In order to evaluate the long-term impact of total fishmeal replacement on intestinal mucosa, the gut mucosa proteome was analysed in fish fed with a fishmeal-based diet, against plant protein-based diets with or without alternative marine sources inclusion. Total fishmeal replacement without marine ingredients inclusion, reported a negative impact in growth and biometric parameters, further an altered gut mucosa proteome. However, the inclusion of a low percentage of marine ingredients in plant protein-based diets was able to maintain the growth, biometrics parameters and gut mucosa proteome with similar values to FM group. A total fishmeal replacement induced a big set of underrepresented proteins in relation to several biological processes such as intracellular transport, assembly of cellular macrocomplex, protein localization and protein catabolism, as well as several molecular functions, mainly related with binding to different molecules and the maintenance of the cytoskeleton structure. The set of downregulated proteins also included molecules which have a crucial role in the maintenance of the normal function of the enterocytes, and therefore, of the epithelium, including permeability, immune and inflammatory response regulation and nutritional absorption. Possibly, the amino acid imbalance presented in VM diet, in a long-term feeding, may be the main reason of these alterations, which can be prevented by the inclusion of 15% of alternative marine sources. Significance: Long-term feeding with plant protein based diets may be considered as a stress factor and lead to a negative impact on digestive and immune system mechanisms at the gut, that can become apparent in a reduced fish performance. The need for fishmeal replacement by alternative ingredients such as plant sources to ensure the sustainability of the aquaculture sector has led the research assessing the intestinal status of fish to be of increasing importance. This scientific work provides further knowledge about the proteins and biologic processes altered in the gut in response to plant protein based diets, suggesting the loss of part of gut mucosa functionality. Nevertheless, the inclusion of alternative marine ingredients was able to reverse these negative effects, showing as a feasible option to develop sustainable aquafeeds., The first author was supported by a contract-grant (Contrato Pre doctoral para la Formacion de Profesorado Universitario) from Subprogramas de Formacion y Movilidad within the Programa Estatal de Promocion del Talento y su Empleabilidad of the Ministerio de Educacion, Cultura y Deporte of Spain.

[Background]: In order to ensure sustainability of aquaculture production of carnivourous fish species such as the gilthead seabream (Sparus aurata, L.), the impact of the inclusion of alternative protein sources to fishmeal, including plants, has been assessed. With the aim of evaluating long-term effects of vegetable diets on growth and intestinal status of the on-growing gilthead seabream (initial weight = 129 g), three experimental diets were tested: a strict plant protein-based diet (VM), a fishmeal based diet (FM) and a plant protein-based diet with 15% of marine ingredients (squid and krill meal) alternative to fishmeal (VM+). Intestines were sampled after 154 days. Besides studying growth parameters and survival, the gene expression related to inflammatory response, immune system, epithelia integrity and digestive process was analysed in the foregut and hindgut sections, as well as different histological parameters in the foregut., [Results]: There were no differences in growth performance (p = 0.2703) and feed utilization (p = 0.1536), although a greater fish mortality was recorded in the VM group (p = 0.0141). In addition, this group reported a lower expression in genes related to pro-inflammatory response, as Interleukine-1β (il1β, p = 0.0415), Interleukine-6 (il6, p = 0.0347) and cyclooxigenase-2 (cox2, p = 0.0014), immune-related genes as immunoglobulin M (igm, p = 0.0002) or bacterial defence genes as alkaline phosphatase (alp, p = 0.0069). In contrast, the VM+ group yielded similar survival rate to FM (p = 0.0141) and the gene expression patterns indicated a greater induction of the inflammatory and immune markers (il1β, cox2 and igm). However, major histological changes in gut were not detected., [Conclusions]: Using plants as the unique source of protein on a long term basis, replacing fishmeal in aqua feeds for gilthead seabream, may have been the reason of a decrease in the level of different pro-inflammatory mediators (il1 β, il6 and cox2) and immune-related molecules (igm and alp), which reflects a possible lack of local immune response at the intestinal mucosa, explaining the higher mortality observed. Krill and squid meal inclusion in vegetable diets, even at low concentrations, provided an improvement in nutrition and survival parameters compared to strictly plant protein based diets as VM, maybe explained by the maintenance of an effective immune response throughout the assay., The research has been partially funded by Vicerrectorat d’Investigació, Innovació i Transferència of the Universitat Politècnica de València, which belongs to the project Aquaculture feed without fishmeal (SP20120603)

[EN] A 154-day trial was performed to assess the use of an alternative protein blend (corn gluten, krill and meat meal) as a substitute for fishmeal in diets for juvenile yellowtail, using four isolipidic (140 g/kg) and isoenergetic diets (24 MJ/kg) with the same digestible protein content (50%). The control diet was FM100, without replacement, and in FM66, FM33 and FM0, fishmeal was replaced at 33 g/kg, 66 g/kg and 100 g/kg, respectively. At the end of the experiment, no differences in growth parameters were observed. Fish fed the FM0 diet exhibited the lowest survival (23%). This high mortality may be due to different factors, such as a dietary amino acid imbalance or some antinutrient factors contained in the alternative ingredients. Feed intake, feed conversion ratio, digestible protein intake and protein efficiency ratio were similar in all diets. However, digestible energy intake and protein efficiency retention were lowest in fish fed the FM0 diet. Apparent digestibility coefficients for protein, energy and amino acids diminished as a substitution for fishmeal increased. Significant differences were observed in the diet whole-fish body profile amino acid retention (AAR) ratio for the seven essential amino acids. In summary, total fishmeal replacement by the blend assayed was not feasible for yellowtail. The FM66 diet resulted in good growth, high survival and good nutrient efficiency, "Ministerio de Ciencia e Innovacion" of the Spanish government, Grant/Award Number: AGL2011-30547-C03-02, Ministerio de Ciencia e Innovacion" of the Spanish government, Grant/Award Number: AGL2011-30547-C03-02

The purpose of this study was to evaluate the effect of two dry extruded diets on growth and nutritional composition of digestive gland (DG) and muscle of Octopus vulgaris. Both artificial diets (FMK and 3FMK) were composed of gelatin, maltodextrin, yolk, fish and krill meal. The 3FMK diet contained more fishmeal (3x) than the FMK diet. These diets were compared with a control frozen diet consisting of golden grey mullet (Liza aurata) and crab (Liocarcinus depurator). The 3FMK diet promoted higher intakes and feed efficiency than FMK diet, resulting in larger growths (296 respect to 158g in 42days; 0.81% vs. 0.78% body weight/day). There was significantly lower moisture, protein and ash content in digestive glands of animals fed pellets (P, This work was financed by JACUMAR (Secretary of Sea, Ministry of Agriculture, Food and Environment) and Conselleria d'Agricultura, Pesca, Alimentacio i Aigua (Generalitat Valenciana).

[EN] Four diets for sharpsnout sea bream juveniles (14 g body weight) with four levels of air-processed pea protein concentrate (PPC) (0, 160, 320 and 487 g/kg diet) were tested in triplicate. The experimental diets were isonitrogenous (43% crude protein) and isolipidic (19% ether extract) and the fish were fed to satiation twice a day. After 125 d, fish growth was diminished by the inclusion of PPC. Feed conversion did not show significant differences in any treatment. Neither the body analyses nor the protein and individual essential amino acid retention efficiencies were affected by the inclusion of PPC in the diet. However, histological gut examinations revealed noticeable differences. Fish fed the diet with the highest inclusion level of PPC presented the longest villous length and the most goblet cells, and the width of the lamina propria increased in the anterior intestine. Although no negative changes in nutritive parameters were detected, these alterations might affect nutrient transport, with negative consequences for fish growth. It was concluded that the PPC in the amounts tested here is an inappropriate substitute for fishmeal in diets for sharpsnout sea bream juveniles., This work was supported by the Generalitat Valenciana; Fisheries Unit of the Valencian Regional Government and Ministerio de Agricultura, Alimentacion y Medio Ambiente (JACUMAR, Spain).

[EN] This study evaluated liver and gut alterations of gilthead sea bream, Sparus aurata L., fed diets in which 12 fish meal was substituted by a mixture (M) of pea protein concentrate (PPC) and rice protein concentrate 13 (RPC). Histological studies were conducted to evaluate the possible changes produced by four 14 experimental isolipidic (18%) and isoproteic (48%CP) diets with 30, 60 and 90% of fish meal substitution 15 by a pea and rice mixture and compared with a control diet (0%). 16 The results obtained in the present histological study showed significant changes especially in the case of 17 the 90% substitution in parameters such as thickness of the layers, goblet cells and villi measurements. 18 Structural integrity of the gut would not be significantly affected by a diet of up to 60% substitution. The 19 alterations observed in the liver could not only be attributed to diet but also to possible individual variations., This study was supported by the Universitat Politecnica de Valencia (UPV PAID-06-08).

[EN] The effect of partial or total dietary substitution of fishmeal (FM) by vegetal protein sources on growth and feed efficiency was carried out in on-growing gilthead sea bream (mean initial weight 131 g). The Control diet (FM 100) contained FM as the primary protein source, while in Diets FM 25 and FM 0 the FM protein was replaced at 75% and 100%, respectively, by a vegetable protein mixture consisting of wheat gluten, soybean meal, rapeseed meal and crystalline amino acids. Diets FM 25 and FM 0 also contained krill meal at 47 g/kg in order to improve palatability. At the end of the trial (after 158 d), fish survival was above 90%. Final weight and the specific growth rate were statistically lower in fish fed the Control diet (361 g and 0.64%/d), compared with 390–396 g and 0.69–0.70%/d after feeding vegetal diets. No significant differences were found regarding feed intake and feed conversion ratio. The digestibility of protein and amino acids (determined with chromium oxide as indicator) was similar in all diets. The blood parameters were not significantly affected by treatments. The activity of trypsin and pepsin was significantly reduced after feeding Diet FM 0. In the distal intestine, the villi length in fish fed Diet FM 25 was significantly longer and the intestine of the fish fed the FM 100 diet showed a smaller number of goblet cells. In conclusion, a total FM substitution by a vegetal mix supplemented with synthetic amino acids in on-growing sea bream is feasible., This work was supported by the Vicerrectorat d'Investigacio, Innovacio i Transferencia - Universitat Politecnica de Valencia, Project Name: Aquaculture feed without fishmeal (SP20120603). URLs of funder:http://www.upv.es/entidades/VIIT/info/indexnormalc.htm. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

This work was financed by JACUMAR (Secretary of Sea, Ministry of Agriculture, Food and Environment) and Conselleria d'Agricultura, Pesca, Alimentacio i Aigua (Generalitat Valenciana).

The use of carob seed germ meal (CG) as a substitute for fish meal was evaluated in fingerlings (average weight 10g) of gilthead sea bream fed isonitrogenous (46% Crude Protein, CP) and isolipidic (19.5% Crude Lipid, CL) diets containing four CG levels (0, 17, 34 and 52%). The duration of the trial was 83days. The diets were tested in triplicate, and the fish were fed to satiation twice daily. The apparent protein and energy digestibility coefficients decreased in response to the dietary inclusion of CG. The decreases in the values of the ADC ranged from 93% for the 0 diet to 80% for the 52 diet. The amount of digestible Arg in the diets increased with the inclusion of CG, from 3.2g Arg 100g -1 in the 0 diet to 4.81g Arg 100g -1 in the 52 diet. The digestible Arg content increased in the diets because the amounts of the remaining digestible amino acids decreased. The fish reached weights of 72, 72, 69 and 53g on the 0, 17, 34 and 52 diets, respectively. The 52 diet gave the lowest specific growth rate (SGR, 1.95%day -1) relative to those found for the other three diets (2.32%day -1). The 52 diet produced the least satisfactory results for feed intake (FI) and the food conversion ratio (FCR) (2.23g 100gfish -1day -1 and 1.38, respectively). The efficiency of retention of His, Phe and Leu in the fish fed the 52 diet showed the lowest values (17.3, 25.5 and 28.5%, respectively), but the efficiency of retention of Met in the fish fed the 52 diet showed the highest value (48.2%).In the distal intestine and liver, histological alterations were found in the fish fed the 34 and the 52 diets. In fish fed the 52 diet, the mucosal fold was significantly shorter and thinner and exhibited a smaller number of goblet cells. These changes could affect nutrient uptake by modifying the digestibility of the diet. The histology of the liver did not show severe degradation in any treatment. The results of the present experiment demonstrated that CG can be included at levels up to 34% in diets for short term feeding of gilthead sea bream without any adverse effects on fish growth and nutritive parameters., Present work was financed by AGROALIMED and GV/2010/046 (Conselleria de Agricultura, Pesca y Alimentacion, Generalitat Valenciana).

Summary The suitability of defatted soybean meal as a substitute for fishmeal was assessed in juvenile (25 g, average) tench, Tinca tinca, by feeding them diets containing 25 (S25), 37.5 (S37.5) and 50% (S50) soybean meal for 150 days. Soybean meal inclusion increased the relationship between essential and non-essential amino acids. Fish were hand-fed to apparent satiation; the feed intake ratio was not dependent upon the dietary soybean level. Survival was over 95% and unaffected by treatment. Growth was reduced at higher soybean meal levels. After 150 days, average weight for the fish fed soybean diets S25, S37.5 and S50 was 65.6, 59.2 and 51 g, respectively. Growth performance was evaluated on the basis of specific growth rate (SGR), final biomass, feed conversion ratio (FCR), and feed intake (FI). Maximum SGR (0.61–0.64) and final biomass (3022–3156 g) were recorded in tench fed diets containing 25 and 37.5% soybean meal. Nutritional parameters such as feed intake and feed conversion ratio were not affected by the soybean meal. Body composition was similar for tench fed the three different diets.

A trial of 218 days of duration was carried out to assess the use of pea protein concentrate (PPC) as a substitute for fish meal in diets for juvenile gilthead sea bream (52 g average initial weight), using four diets (0, 16, 32 and 48) with PPC inclusion levels of 0, 162, 325 and 487 g kg−1, respectively. At the end of the trial, the fish reached weights of 397, 385, 383 and 355 g for 0, 16, 32 and 48 diets, respectively; diet 48 gave the lowest specific growth rate (SGR, 0.88% per day) but 0%, 16% and 32% PPC did not present statistical differences. Feed conversion ratio (FCR), protein efficiency ratio (PER) and body composition were not affected by the diets. Digestible protein retention was significantly higher with the 0% diet, but no energy retention differences were observed. Retention rates of ingested and digestible amino acids were very similar; in general, the retention of essential amino acids decreased as dietary PPC increased, and lysine retention was the highest and phenylalanine retention was the lowest. From the results of this experiment, it may be concluded that fish meal can be replaced up to 32% by PPC in sea bream without negative effects on fish weight gain, FCR and PER.

The suitability of sunflower meal (SFM) as a substitute for fish meal was evaluated in sharpsnout sea bream fingerlings (14 g) by feeding diets in which 0, 10, 20 or 30% of crude protein provided by fish meal was substituted with SFM. The experiment lasted 125 days and survival at the end of the experiment was 95%. The effect of SFM level on growth parameters were not significant ( P

Partial replacement of fish meal by a vegetable mixture (Pea Protein Concentrate (PPC) and Rice Protein Concentrate (RPC)) was carried out in on-growing gilthead seabream (initial average weight 174 g). The experimental diets were isoproteic (48% CP) and isolipidic (18%) with 0, 30, 60 and 90% of fish meal substitution, supplemented with Methionine and Lysine. Fish were distributed in 12 tanks with 20 fish per tank. At the end of the trial (80 days), fish survival was 90% and there were no differences in growth parameters except for fish fed the 90% (326 g and SGR: 0.78% day− 1) diet. No significant differences were found in feed intake ratio (FI), which was around 1.70 to 1.96 g 100 g fish− 1 day− 1, feed conversion ratio, around 1.9 to 2.4 and protein efficiency ratio, which ranged from 0.96 to 1.2. No statistical differences were observed in biometric parameters. In the retention of amino acids ingested there were no statistical differences among diets, although fish fed the 60 diet obtained the highest values in all EAA compared with other diets. In both ingested and digested amino acids, a higher retention of His and lower retention of Met was observed. Regarding sensory analysis, there were no statistical differences in triangular test for fish fed the various diets.

Six isonitrogenous [450 g kg−1 crude protein (CP)] and isoenergetic diets (23 kJ g−1) with six levels of defatted soybean meal inclusion (0, 132, 263, 395, 526 and 658 g kg−1) in substitution of fish meal were evaluated in gilthead sea bream of 242 g initial weight for 134 days. Fish fed diets S0, S13, S26 and S39 had a similar live weight (422, 422, 438 and 422 g, respectively) but fish fed diets S53 and S66 obtained the lowest final weight (385 and 333g, respectively), and similar results were presented in specific growth rate (SGR). Fish fed diets S53 and S66 also obtained the highest feed conversion ratio (FCR). Quadratic multiple regression equations were developed for SGR and FCR which were closely related to dietary soybean level. The optimum dietary soybean levels were 205 g kg−1 for maximum SGR and 10 g kg−1 for minimum FCR. Sensorial differences were appreciated by judges between fish fed S0 and S39 soybean level, but after a re-feeding period of 28 days with diet S0, these differences disappeared.

Background. The aim of this work was to study the growth of juvenile dentex fed on cooking-extruded diets, determine the level of substitution of fishmeal by soybean meal may be without affecting the growth in this species and its digestibility. Materials and methods. The availability of defatted soybean meal as a substitute for fish meal was evaluated in juvenile (41 g on average) dentex by feeding diets containing 0%–60% soybean meal, for 97 days. Results. Survival at the end of the experiment was high (80%) except for the fish fed diets with 50% and 60% substitution. Growth, feed gain ratio, and protein efficiency ratio (PER) were slightly reduced at higher soybean meal levels. Fish fed diets containing 0% to 40% of soybean meal grew significantly more and FCR was lower than fish fed other diets. No differences were obtained for protein digestibility coefficients of experimental diets (20%, 30%, 40%, and 50% SBM). Conclusion. The results confirm the best protein level for optimum growth seems to be around 50% and 12% lipid level, and maximum soybean meal substitution of 40%.

Two parallel experiments were conducted to evaluate the effect of partial substitution of fish meal by two different animal protein sources, blood meal (B) and haemoglobin meal (H) at 0, 50 and 100 g kg−1 of level inclusion in diets for gilthead sea bream, considering a long feeding period for juveniles (Trial 1) and a short feeding period (Trial 2) for on‐growing fish. In Trial 1, 33 g juveniles were fed for 242 days and the fish fed with 5% and 10% of haemoglobin dietary inclusion obtained less growth, although feed efficiency, protein efficiency ratio and muscle composition were similar in all diets. In Trial 2, 179 g initial weight fish were fed for 164 days and growth of fish fed H10 showed the lowest growth, although nutrient efficiency and muscle composition were not affected significantly. The results of these experiments demonstrated that blood meal can substitute fish meal (up to 10%) with no effect on performance, but may lead to sensory differences compared with fish fed diet 0, while the inclusion of 5% blood meal had no effect on growth or sensory characteristics. Fish fed 10% haemoglobin inclusion had the poorest growth values.

The utilisation of sunflower meal as a substitute for fish meal was evaluated in juvenile (44 g ± 4.6 on average) gilthead sea bream fed diets containing four levels of sunflower meal (0, 12, 24 and 36%). The experiment was divided into two phases; in the first one (until day 90), fish reached a weight of 189, 198, 187 and 174 g, respectively, the diet containing 36% gave the lowest specific growth rate (SGR) and the diet containing 12% sunflower meal the highest. In the second phase (from day 91 to day 248), fish growth was not significantly affected by treatments. In relation to feed intake (FI) and feed conversion ratio (FCR), the diet containing 36% sunflower meal gave the worst results in both phases. There were no statistical differences in body composition, but energy and protein efficiency were lowest in fish fed the diet containing 36% sunflower meal. Sensory differences between sea bream fed diets containing 0% and 24% sunflower meal were not detected. Optimum dietary level of sunflower meal for growth and feed conversion obtained from quadratic regression was 10–12%, but when economic aspects were considered, the optimum dietary level was 14–15% sunflower meal.

The present work studies the growth and body composition of 18 Octopus vulgaris (6 per treatment) fed two extruded diets, namely FMS and 3FMS, based on different fish and squid meal ratios (1:1, and 3:1 respectively). The diets are compared with a control diet based on crab (Carcinus mediterraneus) and bogue (Boops boops). The growing tests were conducted on animals placed in individual 300 L rectangular fibreglass tanks in an open seawater system, containing PVC tubes as shelters, resulting in 100% survival rate. The control group exhibited the highest specific growth rates (SGR = 2.14%BW day(-1)), while values of around 0.69% BW day(-1) were achieved by octopuses fed the extruded diets. Even though the three groups of animals showed similar digestive gland indexes, the two extruded diets promoted significant differences in the muscle composition and fatness of the digestive gland. Digestibility of dry matter was not affected by the type of extruded diet, obtaining ADC values of around 88%. The results suggest that squid and fish meal can be both used in dry pelleted extruded diets, with moderate acceptance by the octopus, even though the formulation must be optimized with the aim of improving acceptability and achieve growths in the range of natural diets., This work was financed by JACUMAR (Secretary of Sea, Ministry of Agriculture, Food and Environment) and Conselleria d'Agricultura, Pesca, Alimentacio i Aigua (Generalitat Valenciana).

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., This research was supported by grants from the Planes Nacionales de Acuicultura (JACUMAR) and Conselleria d'Agricultura, Pesca, Alimentacio I Aigua from the Generalitat Valenciana.

The amino acid composition and protein levels of three species of cephalopods (Octopus vulgaris, Loligo gahi and Todarodes sagittatus), the natural diets of common octopus (O. vulgaris) and different kinds of meals were determined in order to optimise the content of these nutrients in artificial feeds. Arginine, leucine and lysine were the most abundant essential amino acids in cephalopods, while glutamate and aspartate represented the main non-essential amino acids. Arginine and leucine were the limiting amino acid in most samples, with maximum Chemical Score values for mussel (79-98 %), squid (84 %) and crustaceans (65-91 %); medium for fish (41-70 %); and minimum for meals (29-64 %). Mussel, squid, crustaceans and fish showed a high essential amino acid index according to Oser (OI: 88-99 %) suggesting a suitable amino acid balance. The protein from animal meals (fish and krill) covered all the essential amino acids except arginine and lysine in fish meal. The vegetable meal presented the worst amino acid balance (OI: 74-89 %) with several deficiencies in essential amino acids, including arginine, threonine, lysine and methionine. Supplementation with arginine or leucine and protein complementation of crustaceans and bivalves with fish or animal meal are proposed as alternatives for improving the performance of protein in feed for cephalopods. © 2012 Springer Science+Business Media B.V., Project financed by the National Marine Culture Plans of JACUMAR.

Four isonitrogenous (42% crude protein) and isolipidic (20%) diets were formulated using four different percentages of pork fat to substitute fish oil at 0, 25, 50 and 75% to evaluate the performance, body composition, fatty acids and liver histology of sharpsnout sea bream juveniles. One hundred and twenty fish (average weight 33.4 ± 2.9 g) were randomly distributed into pens (90 l capacity). Triplicate groups were fed each test diet twice a day to apparent satiation for 84 days. No difference was observed for feeding and growth performance. The only significant difference with respect to carcass was in moisture content (P < 0.05). With respect to liver fatty acids, there were significant differences in EPA and DHA, being fish fed 75% of pork fat that obtained the lowest value. With respect to muscle fatty acids, there were significant differences in saturated fatty acids and fish fed 0% of pork fat obtained the lowest value, but in poly unsaturated fatty acids the 75% of pork fat reported the lowest value. Although in both fish muscle and liver fatty acids, fish fed 75% pork fat diet presented significant difference in n-3 highly unsaturated fatty acids and n3/n6, but in LA fish fed the 0% of pork fat diet presented the lowest value in liver and in fish muscle not only the 0% but also the 25% of pork fat diet obtained the lowest value., This research was supported by grants from the 'Planes Nacionales de Acuicultura (JACUMAR)' and Conselleria de Agricultura Pesca y Alimentacion, Valencia, Spain.

The economic profitability of fish meal replacement by soybean meal and pea-rice concentrate mixture, was analysed considering the economic conversion ratio (ECR) and the economic profit index (EPIst) as a proposal for evaluating the economic profitability in diets for sea bream. The optimal fish meal levels for minimizing the ECR were 33% (when soybean meal was included) and 14% (in the case of pea-rice concentrate mixture) and for maximizing the EPIst, optimal fish meal levels were 31% and 28.8%, respectively, considering the current market price of fish meal and vegetal ingredients. The EPIst, seems to be a better index than the ECR to estimate diet profitability, because it considers weight increment, feed conversion ratio, diet cost and fish sale price. A sensibility analysis was conducted, considering variations in the price of fish meal and vegetal ingredients. Finally, several multiple regressions were developed for estimating the optimal level of fish meal with each vegetable ingredient and the expected value of the economic profit as a function of the market price of both fish meal and plant protein. When fish meal prices increase, the highest beneficial level of the inclusion fish meal and the highest economic profit would be achieved with pea-rice mixture., Elsevier Language Editing Services has revised this manuscript. This work was financed with the support of Generalitat Valenciana (GV/2010/046).

Background. Our previous study demonstrated that sharpsnout seabream, Diplodus puntazzo (Walbaum, 1792), can be fed with up to 34.8% sunflower meal (SFM), with excellent results in growth parameters and feed efficiency. The aim of the current study was to test the replacement of fish meal with SFM in the diet formulation for sharpsnout seabream and to evaluate growth, nutritive parameters, amino acid retention, and body composition of the fish during the fattening period. Materials and methods. Sixteen baskets (300-L capacity), each with thirteen fish, were distributed in a recirculated saltwater system to allow four experimental diets containing 40% crude protein (CP) and 20% crude lipid (CL) with 0%, 11.7%, 23.5%, and 34.8% SFM partially replacing fish meal to be used in quadruplicate for this experiment. The fish were fed these diets ad libitum during the experiment, which lasted for 162 days. Growth, nutrition efficiency, biometrics, carcass composition, amino acid composition, and amino acid retention of the experimental fish were evaluated. Results. There were no statistical differences in the growth parameters among the treatments. However, fish fed a diet containing 34.8% SFM had the lowest feed intake (FI), lowest feed conversion ratio (FCR), and the highest protein efficiency ratio (PER). There were also no statistical differences in the biometric parameters although fish fed the diet containing 10% SFM had the lowest CP levels. Leucine was the only difference in the essential amino acid (EEA) profile with fish fed a diet containing 11.7% SFM having the lowest levels of leucine. Although there were fluctuations among the amino acid retentions, they were not statistically significant. Conclusion. SFM (up to 34.8%) can be included in the diets of sharpsnout seabream, thereby, replacing 27% of the fish meal without altering the fish growth., This research was supported by grants from the Planes Nacionales de Acuicultura (JACUMAR).

The availability of defatted soybean meal as a substitute for fish meal was evaluated in juvenile (450 g on average) yellowtail fed diets containing several levels of soybean meal (from 20 to 50%). After 153 days, liveweight averages were 980, 925, 795 and 670 g for fish fed diets in which fish meal was partially substituted with 20, 30, 40 and 50% soybean meal, and feed conversion ratios were 2.79, 3.09, 4.57 and 6.52, respectively. Regression analysis showed a negative effect of inclusion of soybean, although fish fed diets containing 20% and 30% of soybean did not present statistical differences and grew significantly more, and had a better feed conversion ratio, than fish fed 40 or 50% diets. Likewise, muscle protein level was lower and lipid content was higher in fish fed 20 or 30% soybean. No differences were obtained for protein digestibility coefficients of experimental diets., Sí