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The transcriptome of the seabream larvae farmed in different European commercial hatcheries was analysed during critical larval stages. The complementary data herein presented support the findings reported in the associated research article "Insights into core molecular changes associated with metamorphosis in gilthead seabream larvae across diverse hatcheries". Samples were collected from gilthead seabream (Sparus aurata) hatcheries in Greece (site Gr), Italy (site It), and France (site Fr). RNA was extracted from larvae with different weights, mainly at the flexion (23 and 25 dph) and mid-metamorphosis stages (43, 50, 52, 56, and 60 dph). RNA-seq libraries were sequenced using Illumina HiSeq xten. The paired-end sequenced raw reads were deposited in the NCBI-SRA database with the accession number PRJNA956882. Differential expression and function of genes were obtained by comparing transcriptome profiles of larvae at different developmental stages. The presented data can be used to improve marine-farmed fish larvae production during critical larval stages.

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Classical assessments of new fish feeds are anthropocentric, focusing mainly on growth. Although this methodology is accurate, it does not consider the fish' perspective. This study aimed to investigate the behavioural responses and feed preferences of Nile tilapia (Oreochromis niloticus) and gilthead seabream (Sparus aurata) through a self-selection trial using self-feeders. Both species were offered three feeds: a control (PD) commercial-like feed and two diets (ORG1 and ORG2) formulated with different inclusions of alternative ingredients to address some of the current environmental concerns and/or ethical issues often associated with commercial formulations. Three groups of tilapia with an average weight of 163.0 g ± 4.3 g (mean ± SD) and four groups of seabreams with 174.7 g ± 27.0 g were tested. Tilapia exhibited a preference for ORG2 (46.5%), influenced by the sensory properties of the feed and post-ingestion signals. Seabream did not show a preference for any feed. These findings highlight the effectiveness of self-selection experiments in allowing fish to express their feeding behaviour and preferences. Therefore, this approach should be considered in the initial screening and design of new aquaculture feeds and ingredients.

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Astaxanthin (AX) is a carotenoid known to have one of the highest documented antioxidant capacities and has attracted considerable scientific and commercial interest. The incorporation of AX into aquaculture practices has been associated with improved pigmentation, modulation of the immune and endocrine systems, stress reduction, reproductive efficiency and general fish health. This study describes the effects of dietary AX (0, control, 20, 100 and 500 mg kg-1 AX per kg of diet) for 15 and 30 days on growth performance, immune and antioxidant status, histology and gene expression in gilthead seabream (Sparus aurata). Fish fed diets enriched with 500 mg kg-1 of AX for 15 days decreased in skin mucus peroxidase activity while at 30 days of trial, fish fed a diet supplemented with 20 mg kg-1 AX increased the peroxidase activity in serum. In addition, bactericidal activity against Vibrio harveyi increased in the skin mucus of fish fed any of the AX supplemented diets. Regarding antioxidant activities in the liver, catalase and glutathione reductase were decreased and increased, respectively, in fish fed a diet supplemented with 500 mg kg-1 of AX. Finally, although the expression of up to 21 inflammatory and lipid metabolism-related genes was analysed in visceral adipose tissue, only the expression of the interleukin 6 (il6) gene was up-regulated in fish fed a diet supplemented with 20 mg kg-1 of AX. The present results provide a detailed insight into the potent antioxidant properties of AX and its possible modulatory effects on the immune status and lipid metabolism of seabream, which may be of interest to the aquaculture sector.

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Proteinograms, a semiquantitative analytical method that separates proteins into multiple bands, have not been explored in teleosts for diagnostic or prognostic purposes. This study aimed to establish reference values for proteinograms in the serum of gilthead seabream (Sparus aurata) and European sea bass (Dicentrarchus labrax), two important farmed fish species in the Mediterranean region. Serum proteins were studied using SDS-PAGE, electropherogram, and HPLC-mass spectrometry. SDS-PAGE analysis revealed four major bands of proteins around 11, 25, 70, and 100 kDa in the serum of gilthead seabream and European sea bass. Electropherogram results showed that a protein with a molecular weight of 76.8 kDa was the most abundant protein in the serum of gilthead seabream, while a peak of 75.5 kDa was the most abundant in European sea bass. HPLC-mass spectrometry detected 87 proteins and 119 proteins in the serum of gilthead seabream and European sea bass, respectively, including α1-globulins, α2-globulins, ß-globulins, and γ-globulins. Notably, the albumin sequence was not detected in either of the two species. These results help to characterize the serum protein profile and to establish reference proteinograms for these two fish species. They also provide a basis for the development of novel approaches for the rapid detection of loss of haemostasis due to stress, health disorders or disease in farmed fish.

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Cantharidin is a natural compound with known therapeutic applications in humans. The aim of this study was to investigate the in vitro effects of cantharidin on gilthead seabream (Sparus aurata) head kidney leucocytes (HKL) stimulated with λ-carrageenan. HKLs were incubated for 24 h with cantharidin (0, 2.5 and 5 µg mL-1) and λ-carrageenan (0 and 1000 µg mL-1). The results showed that HKL viability only decreased by 15.2% after incubated with 5 µg mL-1 of cantharidin and λ-carrageenan. Cantharidin increased the peroxidase activity of HKLs only when incubated in combination with λ-carrageenan. Besides this, cantharidin inhibited the respiratory burst and phagocytic activities. Furthermore, cantharidin induced morphological changes in HKLs (apoptotic and vacuolization signs) that were enhanced when incubated with λ-carrageenan. Considering the analysis of the selected gene expression studied in HKLs [NF-κB subunits (rela, relb, crel, nfkb1, nfkb2), proinflammatory cytokines (il1b, tnfa), anti-inflammatory cytokines (il10, tgfb) and caspases (casp1, casp3, casp8, casp9)], although λ-carrageenan up-regulated the expression of the proinflammatory gene il1b, λ-carrageenan and cantharidin down-regulated its expression in HKLs. In addition, cantharidin up-regulated casp3 and casp9 expression. The casp3 and casp9 gene expression was down-regulated while casp1 gene expression was up-regulated in HKLs incubated with both cantharidin and λ-carrageenan. All the effects of cantharidin are related to its inhibitory effect on protein phosphatases, which induce apoptosis at long exposure times, and minimize the effects of λ-carrageenan. The present results provide detailed insight into the immune-depressive and anti-inflammatory properties of cantharidin on immune cells, which could be of interest to the aquaculture sector.

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Antimicrobial peptides (AMPs) are promising molecules in diverse fields, including aquaculture. AMPs possess lytic effects on a wide range of pathogens, resulting in a potential replacement for traditional antimicrobials in aquaculture. In addition, they also have modulatory effects on host immune responses. Thus, the objective of this work was to evaluate the immunomodulatory capability of three known synthetic AMPs derived from European sea bass, NK-lysin (Nkl), hepcidin (Hamp), and dicentracin (Dic), in head-kidney cell suspensions from European sea bass and gilthead seabream. The tested peptides were neither cytotoxic for European sea bass nor gilthead seabream cells and failed to modulate the respiratory burst and phagocytosis activities. However, they modified the pattern of transcription of immune-related genes differently in both species. Peptides were able to promote the expression of marker genes for anti-inflammatory (il10), antiviral (mx, irf3), cell-mediated cytotoxicity (nccrp1, gzmb), and antibody responses (ighm) in European sea bass, with the Nkl peptide being the most effective. Contrary to this, the effects of those peptides on gilthead seabream mainly resulted in the suppression of immune responses. To conclude, European sea bass-derived peptides can be postulated as potential tools for immunostimulation in European sea bass fish farms, but more efforts are required for their universal use in other species.

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The present study investigated the effect of replacing fishmeal (FM) with insect meal of Hermetia illucens (HI) in the diet of Sparus aurata farmed inshore on growth, gut health, and microbiota composition. Two isolipidic (18% as fed) and isoproteic (42% as fed) diets were tested at the farm scale: a control diet without HI meal and an experimental diet with 11% HI meal replacing FM. At the end of the 25-week feeding trial, final body weight, specific growth rate, feed conversion rate, and hepatosomatic index were not affected by the diet. Gross morphology of the gastrointestinal tract and the liver was unchanged and showed no obvious signs of inflammation. High-throughput sequencing of 16S rRNA gene amplicons (MiSeq platform, Illumina) used to characterize the gut microbial community profile showed that Proteobacteria, Fusobacteria, and Firmicutes were the dominant phyla of the gut microbiota of gilthead seabream, regardless of diet. Dietary inclusion of HI meal altered the gut microbiota by significantly decreasing the abundance of Cetobacterium and increasing the relative abundance of the Oceanobacillus and Paenibacillus genera. Our results clearly indicate that the inclusion of HI meal as an alternative animal protein source positively affects the gut microbiota of seabream by increasing the abundance of beneficial genera, thereby improving gut health and maintaining growth performance of S. aurata from coastal farms.

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Pentabromodiphenyl ether (BDE-99) and bisphenol A (BPA) are synthetic organic compounds present in several daily use products. Due to their physicochemical properties, they are ubiquitously present in aquatic ecosystems and considered highly persistent. Recent evidence has confirmed that both emerging compounds are toxic to humans and terrestrial mammals eliciting a wide range of detrimental effects at endocrine and immune levels. However, the ecotoxicological responses that they can trigger in vertebrate marine species have not yet been established. Hence, this study aimed to investigate the ecotoxicological responses of juvenile Sparus aurata upon chronic (28 days) dietary exposure to BDE-99 and BPA (alone and combined) following an integrated multi-biomarker approach that combined fitness indicators (Fulton's K and splenosomatic indexes) with endocrine [cortisol, 17ß-estradiol (E2), 11-ketotestosterone (11-KT) concentrations] and immune (peroxidase and antiprotease activities) endpoints in fish plasma, and oxidative stress [superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) activities, and lipid peroxidation (LPO)] endpoints in the fish spleen. The mixture of BDE-99 and BPA yielded the highest IBR index value in both plasma and spleen biomarkers, therefore, suggesting that the effects of these compounds are more severe when they act together. Endocrine biomarkers were the most responsive in the three contaminated treatments. Fitness indicators were not affected by the individual nor the interactive effects of BDE-99 and BPA. These findings highlight the relevance of accounting for the interactive effects of emerging chemical contaminants and integrating responses associated with distinct biological pathways when investigating their impacts on marine life, as such a multi-biomarker approach provides a broader, more realistic and adequate perspective of challenges faced by fish in a contaminated environment.

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Microplastics (MPs) and nanoplastics (NPs) are widely spread in the environment, generating significant concern due to their potential impact on environmental health. Marine species usually ingest plastic fragments, mistaking them for food. Many toxic compounds, such as plastic additives that are not chemically bound to the plastic matrix, can be released from MPs and NPs and reach humans via the food chain. This paper highlights the development and validation of a straightforward solid-liquid extraction clean-up procedure in combination with a matrix solid-phase dispersion method using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) detection, enabling facile, precise, and reliable identification and quantitation of a total of six bisphenols and phthalates in gilthead sea breams. Under the optimized conditions, the developed method showed good linearity (R2 > 0.993) for all target compounds. The recoveries obtained were between 70 and 92%. The relative standard deviations (RSDs) for reproducibility (inter-day) and repeatability (intra-day) were less than 9% and 10%, respectively. The limit of detection (LOD) and limit of quantification (LOQ) for the target compounds ranged from 0.11 to 0.68 µg/kg and from 0.37 to 2.28 µg/kg, respectively. A new, efficient extraction methodology for the determination of BPA, BPS, BPF, DBP, DEP, and DHEP in gilthead seabream has been optimized and validated.

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Yeast, Saccharomyces cerevisiae, has been utilized as a probiotic in aqua-feeds to promote growth and alleviate the stress in aquatic animals. On the other hand, cadmium (Cd) toxicity causes serious retardation of growth and welfare status of aquatic animals. The present study was conducted to evaluate the protective role of dietary yeast in mitigating the waterborne Cd toxicity effects on the growth, haemato-biochemical, stress biomarkers, and histopathological investigations of gilthead seabream (Sparus aurata L.). In a 3 × 3 factorial design, the acclimated fish (20-24 g) were randomly distributed into nine treatments in triplicates where they were fed on 0.0% (control), 0.5%, and 1.0% of yeast along with exposure to 0.0, 1.0, and 2.0 mg Cd/L for 60 days. All growth parameters and mRNA expressions of IGF-1 and GH genes as well as haematological parameters were markedly increased with the increase of dietary yeast levels; meanwhile these variables were significantly retarded with Cd exposure. Contradictory effects on the above-mentioned variables were observed with Cd toxicity. In contrast, blood cortisol, glucose, total cholesterol, and triglyceride, lactate dehydrogenase, alanine transaminase, aspartate transaminase, alkaline phosphatase, in addition to DNA fragments % were noticeably increased with Cd toxicity especially at the treatment of 2.0 mg Cd/L, while decreasing with increasing dietary yeast levels. Compared with the control fish group, Cd concentrations in the gill, liver, and muscle tissues of gilthead seabream were higher in Cd-exposed treatments, especially at the treatment of 2.0 mg Cd/L. Deposition of Cd in fish liver was higher than that in gill tissues but lowest Cd residue was observed in muscle tissues. No significant changes in Cd residues in fish organs were observed in yeast-fed fish with no Cd exposure. The Cd exposure negatively affected histological status of gill, liver, and kidney tissues of S. aurata; while feeding Cd-exposed fish on yeast diets lowered the Cd residues in fish organs and recovered the adverse effects of Cd toxicity. Hence, this study recommends the addition of bakery yeast (1.0%) to fish diets to improve the performance, overall welfare, and histopathological status of gilthead seabream, S. aurata.

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The gilthead seabream, one of the most important species in Mediterranean aquaculture, with an increasing status of exploitation in terms of production volume and aquafarming technologies, has become an important research topic over the years. The accumulation of knowledge from several studies conducted during recent decades on their functional and biological characteristics has significantly improved their aquacultural aspects, namely their reproductive success, survival, and growth. Despite the remarkable progress in the aquaculture industry, hatchery conditions are still far from ideal, resulting in frequent abnormalities at the beginning of intensive culture, entailing significant economic losses. Those deformities are induced during the embryonic and post-embryonic periods of life, and their development is still poorly understood. In the present review, we created a comprehensive synthesis that covers the various aspects of skeletal morphogenesis and anomalies in the gilthead seabream, highlighting the genetic, environmental, and nutritional factors contributing to bone deformities and emphasized the potential of the gilthead seabream as a model organism for understanding bone morphogenesis in both aquaculture and translational biological research. This review article addresses the existing lack in the literature regarding gilthead seabream bone deformities, as there are currently no comprehensive reviews on this subject.

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The present study was designed to evaluate the effects of dietary levels of bioactive peptides (BPs) derived from salmon processing by-products on the presence and distribution of peptic cells (oxyntopeptic cells, OPs) and enteric endocrine cells (EECs) that contain GHR, NPY and SOM in the gastric mucosa of European seabass and gilthead seabream. In this study, 27 seabass and 27 seabreams were divided into three experimental groups: a control group (CTR) fed a control diet and two groups fed different levels of BP to replace fishmeal: 5% BP (BP5%) and 10% BP (BP10%). The stomach of each fish was sampled and processed for immunohistochemistry. Some SOM, NPY and GHR-IR cells exhibited alternating "open type" and "closed type" EECs morphologies. The BP10% group (16.8 ± 7.5) showed an increase in the number of NPY-IR cells compared to CTR (CTR 8.5 ± 4.8) and BP5% (BP10% vs. CTR p ≤ 0.01; BP10% vs. BP5% p ≤ 0.05) in the seabream gastric mucosa. In addition, in seabream gastric tissue, SOM-IR cells in the BP 10% diet (16.8 ± 3.5) were different from those in CTR (12.5 ± 5) (CTR vs. BP 10% p ≤ 0.05) and BP 5% (12.9 ± 2.5) (BP 5% vs. BP 10% p ≤ 0.01). EEC SOM-IR cells increased at 10% BP (5.3 ± 0.7) compared to 5% BP (4.4 ± 0.8) (5% BP vs. 10% BP p ≤ 0.05) in seabass. The results obtained may provide a good basis for a better understanding of the potential of salmon BPs as feed ingredients for seabass and seabream.

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Skeletal disorders are problematic aspects for the aquaculture industry as skeletal deformities, which affect most species of farmed fish, increase production costs and affect fish welfare. Following recent findings that show the presence of osteoactive compounds in marine organisms, we evaluated the osteogenic and mineralogenic potential of commercially available microalgae strains Skeletonema costatum and Tetraselmis striata CTP4 in several fish systems. Ethanolic extracts increased extracellular matrix mineralization in gilthead seabream (Sparus aurata) bone-derived cell cultures and promoted osteoblastic differentiation in zebrafish (Danio rerio) larvae. Long-term dietary exposure to both extracts increased bone mineralization in zebrafish and upregulated the expression of genes involved in bone formation (sp7, col1a1a, oc1, and oc2), bone remodeling (acp5a), and antioxidant defenses (cat, sod1). Extracts also improved the skeletal status of zebrafish juveniles by reducing the incidence of skeletal anomalies. Our results indicate that both strains of microalgae contain osteogenic and mineralogenic compounds, and that ethanolic extracts have the potential for an application in the aquaculture sector as dietary supplements to support fish bone health. Future studies should also identify osteoactive compounds and establish whether they can be used in human health to broaden the therapeutic options for bone erosive disorders such as osteoporosis.

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Aerobic swimming exercise in fish has been shown to improve robustness of some species. However, the optimal conditions to be applied and the mechanisms underlying remain unknown. We investigated the effects of 6 h of induced swimming on the immune response of gilthead seabream (Sparus aurata), by analysing markers related to immune status in plasma, skin mucus, gills, heart and head-kidney. Forty fish were individually exercised in swim tunnels by applying different water currents: steady low (SL, 0.8 body lengths (BL) s-1), steady high (SH, 2.3 BL s-1), oscillating low (OL, 0.2/0.8 BL s-1) and oscillating high (OH, 0.8/2.3 BL s-1) velocities, including a non-exercised group with minimal water flow (MF, <0.1 BL s-1). Swimming conditions did not trigger a stress response or anaerobic metabolism, suggested by similar levels of cortisol, lactate, and glucose in plasma among groups. Blood haemoglobin and innate immune parameters in plasma and skin mucus also remained unaltered. However, decreased blood haematocrit was observed in fish swimming on the OL condition. Interestingly, gene expression analysis revealed that the OL condition led to the up-regulation of pro-inflammatory mediators (nfκb1 and mapk3) and cytokines (tnfα, il1ß and il6) in gills. A similar response occurred in heart, with an up-regulation of nfκb1, tnfα, il6 and cox2 in the OL condition. Gene expression of these cytokines was unaltered in the head-kidney. The inflammatory response in gills and heart of gilthead seabream triggered by the OL condition highlights the importance of establishing suitable rearing conditions to improve welfare of cultured fish.

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Lymphocystis disease is one of the main viral pathologies affecting cultured gilthead seabream (Sparus aurata) in the Mediterranean region. Recently, we have developed a DNA vaccine based on the major capsid protein (MCP) of the Lymphocystis disease virus 3 (LCDV-Sa). The immune response triggered by either LCDV-Sa infection or vaccination have been previously studied and seem to be highly related to the modulation of the inflammatory and the IFN response. However, a comprehensive evaluation of immune-related gene expression in vaccinated fish after viral infection to identify immunogenes involved in vaccine-induced protection have not been carried out to date. The present study aimed to fulfill this objective by analyzing samples of head-kidney, spleen, intestine, and caudal fin from fish using an OpenArray® platform containing targets related to the immune response of gilthead seabream. The results obtained showed an increase of deregulated genes in the hematopoietic organs between vaccinated and non-vaccinated fish. However, in the intestine and fin, the results showed the opposite trend. The global effect of fish vaccination was a significant decrease (p<0.05) of viral replication in groups of fish previously vaccinated, and the expression of the following immune genes related to viral recognition (tlr9), humoral and cellular response (rag1 and cd48), inflammation (csf1r, elam, il1ß, and il6), antiviral response (isg15, mx1, mx2, mx3), cell-mediated cytotoxicity (nccrp1), and apoptosis (prf1). The exclusive modulation of the immune response provoked by the vaccination seems to control the progression of the infection in the experimentally challenged gilthead seabream.

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Chemical contaminants such as heavy metals, polybrominated diphenyl ethers (PBDEs) and drugs, are constantly found in the marine environment determining the interest of the scientific community for their side effects on animal welfare, food safety and security. Few studies have analyzed the effects of mix of contaminants in fish, in terms of molecular and nutritional composition response, beside it is indispensable to think more and more on effect of contaminants along the food web system. In this study, Sparus aurata specimens were exposed for 15 days, by diet, to a mixture of carbamazepine (Cbz), polybrominated diphenyl ether-47 (PBDE-47) and cadmium chloride (CdCl2), at two doses (0.375 µg g-1 D1; 37.5 µg g-1 D2) (T15). After, fish were fed with a control diet, without contaminants mix, for other 15 days (T30). The study explored the effect on oxidative stress in the liver, analyzing specific molecular markers and effects on quality, by fatty acid profile and lipid peroxidation. Molecular markers involved in ROS scavenging, such as superoxide dismutase (sod), catalase (cat) and glutathione peroxidase (gpx) were evaluated by gene expression; as markers of quality and lipid peroxidation, the fatty acids (FAs) profile and the level of malondyaldeide (MDA) were assessed. Sod and cat genes underwent to up-regulation after 15 days of diet containing contaminants and showed down-regulation after the next 2 weeks of detoxification (T30). At T15, the FAs profile showed an increase of the saturated fatty acids (SFA), and a decrease of the polyunsatured fatty acids (PUFA). The MDA levels increased over time, indicating an ongoing radical damage. These results suggest that the effects of the contaminants can be perceived not only at molecular but also at nutritional level and that the molecular and biochemical markers adopted could be differently used to monitor the health of aquatic organisms in the marine environment.

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Vibrio harveyi, a significant opportunistic marine pathogen, has been a challenge to the aquaculture industry, leading to severe economical and production losses. Phage therapy has been an auspicious approach in controlling such bacterial infections in the era of antimicrobial resistance. In this study, we isolated and fully characterized a novel strain-specific phage, vB_VhaS_MAG7, which infects V. harveyi MM46, and tested its efficacy as a therapeutic agent in challenged gilthead seabream larvae. vB_VhaS_MAG7 is a tailed bacteriophage with a double-stranded DNA of 49,315 bp. No genes linked with virulence or antibiotic resistance were harbored in the genome. The phage had a remarkably large burst size of 1393 PFU cell-1 and showed strong lytic ability in in vitro assays. When applied in phage therapy trials in challenged gilthead seabream larvae, vB_VhaS_MAG7 was capable of improving the survival of the larvae up to 20%. Due to its distinct features and safety, vB_VhaS_MAG7 is considered a suitable candidate for applied phage therapy.

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The rapid development of intensive fish farming has been associated with the spreading of infectious diseases, pathogens and parasites. One such parasite is Sparicotyle chrysophrii (Platyhelminthes: Monogenea), which commonly infects cultured gilthead seabream (Sparus aurata)-a vital species in Mediterranean aquaculture. The parasite attaches to fish gills and can cause epizootics in sea cages with relevant consequences for fish health and associated economic losses for fish farmers. In this study, a novel stratified compartmental epidemiological model of S. chrysophrii transmission was developed and analysed. The model accounts for the temporal progression of the number of juvenile and adult parasites attached to each fish, as well as the abundance of eggs and oncomiracidia. We applied the model to data collected in a seabream farm, where the fish population and the number of adult parasites attached to fish gills were closely monitored in six different cages for 10 months. The model successfully replicated the temporal dynamics of the distribution of the parasite abundance within fish hosts and simulated the effects of environmental factors, such as water temperature, on the transmission dynamics. The findings highlight the potential of modelling tools for farming management, aiding in the prevention and control of S. chrysophrii infections in Mediterranean aquaculture.

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This study provided new data and knowledge on the potential use of Hermetia illucens meal (HIM) as a new sustainable ingredient for Sparus aurata diet. The effect of HIM dietary inclusion on fish growth performance, stress indicators and gut histology was studied. For 131 days, 312 fish were fed a basal diet containing fishmeal as animal protein source, and three diets containing 25%, 35% and 50% HIM as a partial replacement for fishmeal. The main findings indicated that fishmeal can be replaced by HIM up to 110 g/kg of substitution (35% of inclusion in diet) without negative effects on growth performance, stress parameters or histological traits of the posterior gut tract, and with positive effects (p < 0.05) on the histological and morphometric characteristics of the anterior gut tract. At the same time, the results showed that the effect of Hermetia illucens meal at 50% inclusion level caused morphometric and histopathological alterations in the anterior gut tract of seabream. In conclusion, this preliminary study suggested that the dietary inclusion level of HIM35 was the most tolerated by fish showing the best gut morphometric parameters and histological conditions, with fewer signs of inflammation, as well as good nutritional and health status.