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Bibliografia, Premi Extraordinari de Doctorat concedit pels programes de doctorat de la UAB per curs acadèmic 2016-2017, El Mar Mediterráneo profundo permanece en gran parte inexplorado, y, específicamente, las comunidades parásitas de los peces mediterráneos de aguas profundas son mayormente desconocidas. El principal objetivo de la presente tesis es caracterizar las comunidades parásitas de las importantes especies ícticas de aguas profundas siguientes: Mora moro (Risso, 1810), Phycis blennoides (Brünnich, 1768), Galeus melastomus Rafinesque, 1810, Scyliorhinus canicula (Linnaeus, 1758), Etmopterus spinax (Linnaeus, 1758) y Centroscymnus coelolepis Barbosa du Bocage and de Brito Capello, 1864. Otro propósito importante es evaluar la respuesta de estas comunidades a gradientes y variables ambientales, a la dieta y a la ecología trófica de los hospedadores y su posible impacto en el estado de salud de estos últimos. En los capítulos tercero a sexto se describen las comunidades parásitas de las especies mencionadas en diferentes estaciones, estratos de profundidad y localidades de las vertientes continental e insular del Mar Balear. Mientras que las comunidades parásitas de M. moro, P. blennoides y G. melastomus se caracterizaron por altos valores abundancia, riqueza y diversidad, las de S. canicula, E. spinax y C. coelolepis eran comparativamente más pobres y menos diversas. Diferencias ontogénicas, batimétricas, estacionales y geográficas se detectaron en las comunidades parásitas de las especies tratadas, en todos los casos asociadas a las dinámicas alimentarias (a su vez asociadas a la disponibilidad de presas a lo largo de los gradientes mencionados, en la mayoría de casos) de sus hospedadores. Se hallaron relaciones detalladas entre parásitos y presas ingeridas por los diferentes hospedadores, permitiendo confirmar las vías de transmisión ya conocidas para algunos parásitos y sugiriendo nuevas vías de infección para otros. La mayoría de parásitos se asociaron a altos niveles de O2 y turbidez del agua. Mientras que los primeros favorecen la abundancia de parásitos con ciclos indir, The Mediterranean deep-sea remains mostly unexplored and, specifically, the parasite communities of Mediterranean deep-dwelling fishes are largely unknown. The central purpose of the present thesis is to characterize the parasite communities infecting the following important deep-dwelling ichthyc species in the Balearic Sea: Mora moro (Risso, 1810), Phycis blennoides (Brünnich, 1768), Galeus melastomus Rafinesque, 1810, Scyliorhinus canicula (Linnaeus, 1758), Etmopterus spinax (Linnaeus, 1758) and Centroscymnus coelolepis Barbosa du Bocage and de Brito Capello, 1864. Another main objective is to assess the responsiveness of these parasite communities to environmental gradients and variables, to host diet and trophic ecology and their possible impact on host health condition. In the third to sixth chapters, the parasite communities of the mentioned species are described on different seasons, depth strata and localities from the mainland and insular slopes of the Balearic Sea. While parasite communities of M. moro, P. blennoides and G. melastomus were characterized by high abundance, richness and diversity values, those of S. canicula, E. spinax and C. coelolepis were comparatively poorer and less diverse. Ontogenic, bathymetric, seasonal and geographic differences in the parasite communities of the different species addressed were detected, in all cases linked to the feeding dynamics (in turn linked to prey availability across the mentioned gradients, in most cases) of their hosts. Detailed relationships were found between parasite taxa and prey ingested by the different hosts, allowing confirmation of the transmission pathways known for some parasites and suggesting new ways of infection in others. Most parasites were linked to high O2 and turbidity levels. While the former enhances the abundance of parasites with indirect life cycles as a result of zooplankton proliferation and the associated aggregation of potential intermediate hosts, the latter favours parasite

With the objective to build up a positive image of aquaculture and taken into account the results found, the issue of >farmed fish feeding> was selected as one of the most important myths of aquaculture. Then the specific objectives were the following: 1) to build a sound and readable documentation on farmed fish feeding, 2) to test two different tools to give the information to consumers, in order to establish the better way to communicate the information, 3) to study whether the message could change the perception of consumers in front of the chosen myth, and 4) to provide the sector with documents and tools easily usable for the dissemination. This last objective is the ultimate goal of the project., Postprint (published version)

Acute organophosphorus (OP) intoxication is a worldwide clinical and public health problem. In addition to cholinergic crisis, neurodegeneration and brain damage are hallmarks of the severe form of this toxidrome. Recently, we generated a chemical model of severe acute OP intoxication in zebrafish that is characterized by altered head morphology and brain degeneration. The pathophysiological pathways resulting in brain toxicity in this model are similar to those described in humans. The aim of this study was to assess the predictive power of this zebrafish model by testing the effect of a panel of drugs that provide protection in mammalian models. The selected drugs included “standard therapy” drugs (atropine and pralidoxime), reversible acetylcholinesterase inhibitors (huperzine A, galantamine, physostigmine and pyridostigmine), N-methyl-d-aspartate (NMDA) receptor antagonists (MK-801 and memantine), dual-function NMDA receptor and acetylcholine receptor antagonists (caramiphen and benactyzine) and anti-inflammatory drugs (dexamethasone and ibuprofen). The effects of these drugs on zebrafish survival and the prevalence of abnormal head morphology in the larvae exposed to 4 µM chlorpyrifos oxon [1 × median lethal concentration (LC50)] were determined. Moreover, the neuroprotective effects of pralidoxime, memantine, caramiphen and dexamethasone at the gross morphological level were confirmed by histopathological and transcriptional analyses. Our results demonstrated that the zebrafish model for severe acute OP intoxication has a high predictive value and can be used to identify new compounds that provide neuroprotection against severe acute OP intoxication. © 2016, The Author(s).

Acrylamide (ACR), a type-2 alkene, may lead to a synaptopathy characterized by ataxia, skeletal muscles weakness and numbness of the extremities in exposed human and laboratory animals. Currently, only the mildly affected patients undergo complete recovery, and identification of new molecules with therapeutic bioactivity against ACR acute neurotoxicity is urgently needed. Here, we have generated a zebrafish model for ACR neurotoxicity by exposing 5 days post-fertilization zebrafish larvae to 1 mM ACR for 3 days. Our results show that zebrafish mimics most of the pathophysiological processes described in humans and mammalian models. Motor function was altered, and specific effects were found on the presynaptic nerve terminals at the neuromuscular junction level, but not on the axonal tracts or myelin sheath integrity. Transcriptional markers of proteins involved in synaptic vesicle cycle were selectively altered, and the proteomic analysis showed that ACR-adducts were formed on cysteine residues of some synaptic proteins. Finally, analysis of neurotransmitters profile showed a significant effect on cholinergic and dopaminergic systems. These data support the suitability of the developed zebrafish model for screening of molecules with therapeutic value against this toxic neuropathy. © 2017 The Author(s).

Microplastic pollution is currently one of the most concerning threats for wildlife. Ingestion of microplastics has been confirmed in a wide variety of marine species (Lusher et al.,2017). However, their potential effects remain unclear and only a few studies have addressed this issue in natural environments. The present study aims to assess the presence and potential effects of microplastics in the shrimp Aristeus antennatus, with a particular focus on diet

El objetivo de este estudio es realizar una evaluación preliminar de la presencia de microplásticos en estómagos de en relación a la distancia de una fuente de contaminación. Los microplásticos, en especial las fibras que pueden enredarse y formar ovillos, pueden acumularse en sus estómagos por lo que podrían ser una amenaza para la condición de vida de estos crustáceos

Introduction and Objectives: In the previous EAS congress (2016), the first part of a project dealing with the perceptions towards aquaculture from a value chain approach was presented by Flos et al. (2016) and Escobar et al. (2016). One of the strongest conclusions was the lack of information about the production of farmed fish. Here we present the second part of the project, a Delphi study in order to confirm the perceptions that were previously reached. With the objective to build up a positive image of aquaculture and taken into account the results found, the issue of >farmed fish feeding> was selected as one of the most important myths of aquaculture. Then the specific objectives were the following: 1) to build a sound and readable documentation on farmed fish feeding, 2) to test two different tools to give the information to consumers, in order to establish the better way to communicate the information, 3) to study whether the message could change the perception of consumers in front of the chosen myth, and 4) to provide the sector with documents and tools easily usable for the dissemination. This last objective is the ultimate goal of the project.

Changes on an organism by the exposure to environmental stressors may be characterized by hyperspectral images (HSI), which preserve the morphology of biological samples, and suitable chemometric tools. The approach proposed allows assessing and interpreting the effect of contaminant exposure on heterogeneous biological samples monitored by HSI at specific tissue levels. In this work, the model example used consists of the study of the effect of the exposure of chlorpyrifos-oxon on zebrafish tissues. To assess this effect, unmixing of the biological sample images followed by tissue-specific classification models based on the unmixed spectral signatures is proposed. Unmixing and classification are performed by multivariate curve resolution-alternating least squares (MCR-ALS) and partial least squares-discriminant analysis (PLS-DA), respectively. Crucial aspects of the approach are: (1) the simultaneous MCR-ALS analysis of all images from 1 population to take into account biological variability and provide reliable tissue spectral signatures, and (2) the use of resolved spectral signatures from control and exposed populations obtained from resampling of pixel subsets analyzed by MCR-ALS multiset analysis as information for the tissue-specific PLS-DA classification models. Classification results diagnose the presence of a significant effect and identify the spectral regions at a tissue level responsible for the biological change.

The parasite communities of sharks have been largely neglected despite the ecological importance and vulnerability of this group of fishes. The main goal of the present study is to describe the parasite communities of three deep-dwelling shark species in the NW Mediterranean. A total of 120 specimens of Galeus melastomus, 11 Etmopterus spinax and 10 Centroscymnus coelolepis were captured at 400–2200 m depth at two seasons and three localities off the mainland and insular slopes of the Balearic Sea. Environmental and fish biological, parasitological, dietary, enzymatic and histological data were obtained for each specimen, and the relationships among them tested. For G. melastomus, E. spinax and C. coelolepis a total of 15, two and eight parasite species were respectively recovered. The parasite community of G. melastomus is characterized by high abundance, richness and diversity, and the cestodes Ditrachybothridium macrocephalum and Grillotia adenoplusia dominate the infracommunities of juvenile and adult specimens, respectively. A differentiation of parasite communities, linked to a diet shift, has been observed between ontogenic stages of this species. E. spinax displays a depauperate parasite community, and that of C. coelolepis, described for the first time, shows moderate richness and diversity. Detailed parasite-prey relationships have been discussed and possible transmission pathways suggested for the three hosts. Parasites were mostly related to high water turbidity and O levels, which enhance zooplankton proliferation and could thus enhance parasite transmission. The nematodes Hysterothylacium aduncum and Proleptus obtusus were linked to high salinity levels, as already reported by previous studies, which are associated to high biomass and diversity of benthic and benthopelagic crustaceans. A decrease of acetylcholinesterase activity and lower hepatosomatic index, possibly linked to infection-related stress, have been observed. Lesions associated to encapsu

[EN] The Mediterranean deep-sea remains mostly unexplored and, specifically, the parasite communities of Mediterranean deep-dwelling fishes are largely unknown. Parasites are known to be effective bioindicators. Because many of them are trophically-transmitted and show complex life cycles involving more than one host, parasites can reflect host feeding habits, trophic interactions and species composition of their ecosystems. Parasites can also reveal environmental changes of anthropogenic or natural origin, and respond to environmental conditions that may influence their own biology or their hosts’ population dynamics. Furthermore, the differentiation of parasite communities across geographical gradients allows their use as discrimination tags of host populations. [...], [ES] El Mar Mediterráneo profundo permanece en gran parte inexplorado, y, específicamente, las comunidades parásitas de los peces mediterráneos de aguas profundas son mayormente desconocidas. Es sabido que los parásitos son efectivos bioindicadores. Debido a que muchos de ellos se transmiten por vía trófica y tienen complejos ciclos vitales que involucran a más de un hospedador, los parásitos pueden reflejar los hábitos alimentarios de sus hospedadores, interacciones tróficas y la composición de especies de sus ecosistemas. Los parásitos pueden también poner de manifiesto cambios ambientales de origen antropogénico o natural, y responder a condiciones ambientales que influyan en su propia biología o en las dinámicas poblacionales de sus hospedadores. Asimismo, la diferenciación de las comunidades de parásitos a lo largo de gradientes geográficos posibilita su uso como marcadores de discriminación de las poblaciones de hospedadores. [...]

Mediterranean rivers are probably one of the most singular and endangered ecosystems worldwide due to the presence of many endemic species and a long history of anthropogenic impacts. Besides a conservation value per se, biodiversity is related to the services that ecosystems provide to society and the ability of these to cope with stressors, including climate change. Using macro-invertebrates and fish as sentinel organisms, this overview presents a synthesis of the state of the art in the application of biomarkers (stress and enzymatic responses, endocrine disruptors, trophic tracers, energy and bile metabolites, genotoxic indicators, histopathological and behavioural alterations, and genetic and cutting edge omic markers) to determine the causes and effects of anthropogenic stressors on the biodiversity of European Mediterranean rivers. We also discuss how a careful selection of sentinel species according to their ecological traits and the food-web structure of Mediterranean rivers could increase the ecological relevance of biomarker responses. Further, we provide suggestions to better harmonise ecological realism with experimental design in biomarker studies, including statistical analyses, which may also deliver a more comprehensible message to managers and policy makers. By keeping on the safe side the health status of populations of multiple-species in a community, we advocate to increase the resilience of fluvial ecosystems to face present and forecasted stressors. In conclusion, this review provides evidence that multi-biomarker approaches detect early signs of impairment in populations, and supports their incorporation in the standardised procedures of the Water Frame Work Directive to better appraise the status of European water bodies.

Systemic amoebiasis of sole is caused by Endolimax piscium, a cryptic parasitic archamoeba whose epidemiology and pathogeny are yet unknown. To establish reliable detection methods for this parasite, a battery of molecular diagnostic tools (ISH, PCR and qPCR) were developed and evaluated with a panel of clinical samples from symptomatic diseased fish and from apparently normal animals of different stocks. As there is neither enough background information on the epidemiology of the disease nor a validated reference method, comparison of tests used a composite reference method approach. The ISH technique was the most specific and sensitive in intestine samples and particularly useful as a reference confirmatory method, while the best method in muscle samples was qPCR. Application of the tests to asymptomatic fish demonstrated presence of parasites in a large proportion (>25%) of their intestines, suggesting that this is the point of entry of the amoebae and the initial stage in the development of the disease. The triggering factors that facilitate the breaching of the intestinal barrier by E. piscium, causing granulomatous lesions in other organs and systemic spreading, are not completely understood but our results point to the connective tissue as a preferential target for parasite development and migration.

There are many studies that explore consumer's perception towards aquaculture, but studies focusing specifically on the supply-chain perception are scarce. Consumers' perceptions towards aquaculture could become a bottleneck for the sector's full development. Nevertheless, consumer's buying decisions are directly affected by their fishmongers' advice and by the availability of fish on the central markets. In this context the main objective of this paper is to describe the perception about aquaculture at two steps of the supply-chain, wholesalers (from Mercabarna, the central market of Barcelona) and retailers (fishmongers from different local markets of the city). Specifically, we determine which positive and negative perceptions do the fish traders derive from the products provided by the fish farm industry

The greater forkbeard Phycis blennoides is a benthopelagic fish distributed in the Mediterranean and NE Atlantic. The main goal of this study is to describe the complete parasite community of this species, which is at present unknown. A total of 188 specimens of P. blennoides were captured in the Balearic Sea (NW Mediterranean Sea) at 550–1250 m depth during the four seasons of 2007, in summer of 2010 and in summer and autumn of 2011 at five distinct localities off the mainland slope off Catalonia coasts and off the insular slope off the Balearic Islands. Environmental and fish biological, parasitological, dietary, enzymatic and histological data were obtained and the relationships among them tested. A total of 20 different parasites were recovered, of which 11 constitute new host records. The most important parasites were the monogenean Diclidophora phycidis, the digeneans Bathycreadium brayi and Lepidapedon spp., the nematodes Capillaria gracilis, Collarinema collaris, Cucullanus sp. and Hysterothylacium aduncum, and the copepod Clavella alata. Overall, the parasite community of P. blennoides was characterized by high abundance, richness and diversity. Significant differences in the structure of the parasite community were detected between samples from <1000 to >1000 m depth and between samples from off the mainland and insular slopes. Significant seasonal and/or geographical differences were found for some specific parasites. Abundance of the nematode C. collaris was associated to high levels of turbidity and O concentrations near the bottom. Abundances of H. aduncum, D. phycidis, B. brayi and Lepidapedon spp. were linked to high near-bottom temperature and salinity. Dietary analyses evidenced the role as potential intermediate hosts in parasite transmission by some prey (e.g. the teleost Gaidropsarus biscayensis for the cestode Grillotia cf. erinaceus and the nematodes Anisakis spp. or the euphausiid Meganyctiphanes norvegica for the acanthocephalan Echinorhynch

Aquaculture is one of the food sectors with a higher potential for growth. The sector incorporates every time a higher level of scientific and technological advances. However, in Spain, consumers’ unawareness about the production and its processes seems to play against the sector., Postprint (published version)

Despite their importance and vulnerability, deep-dwelling elasmobranchs are still poorly understood. In this context, this study aims to perform a parasitological survey of the blackmouth catshark Galeus melastomus Rafinesque, 1810 in deep waters of the north-western Mediterranean Sea describing variability on the parasite community between host maturity stages and its relation to diet and health condition of the host. A total of 120 specimens of G. melastomus were captured in 2010-2011 at 400-1,400 m depth in three different locations of the Balearic basin using a semi-balloon ottertrawl. Parasitological, dietary, enzymatic stress indicators and histological data were obtained according to standardized protocols. Main relationships among fish parasite load, size, condition indices, enzymatic activity of muscular acetylcholinesterase, lactate dehydrogenase and citrate synthase and intensity of hepatic melano-macrophages were tested. A total of 16 different parasite taxa were found: one coccidian, one monogenean, one digenean, five cestodes, seven nematodes and one copepod. The most important parasites in terms of prevalence and abundance showed a significant relationship with host size, probably reflecting hosts ontogenic diet shifts: the digenean Otodistomum sp., the cestodes Scolex pleuronectis and Grillotia cf. adenoplusia and the copepod Eudactylina cf. vilelai were linked to adult sharks, while the cestode Ditrachybothridium macrocephalum characterized juvenile hosts. Overall results considering associations between parasite infection parameters and health condition of their hosts yield the conclusion that, in the present study, the intensity of parasite infections does not negatively affect fish health.

This study examines the parasite communities of Alepocephalus rostratus and its influence on some fish biochemical markers and histological alterations. A. rostratus constitutes the second most important fish species, in terms of biomass, inhabiting the deep slope of the Catalan Sea (Balearic Sea, NW Mediterranean). The study revealed eight different parasite species in this host: one coccidian, one digenean, one monogenean, one cestode and four nematodes. The parasite fauna of A. rostratus was partially dominated by larval forms (four of the seven metazoan taxa found), which combined with low species richness corresponds to a parasite fauna pattern more typical of bathypelagic fish species rather than demersal ones. The larval tetraphyllideans and cucullanid nematodes were the predominant species. In relation to depth, differences in abundance of the nematodes Cucullaninae gen. sp. and Hysterothylacium aduncum were found, probably due to the dietary shift in the fish host at greater depth. Thus, Cucullaninae gen. sp. and H. aduncum could be regarded as indicators for discriminating populations of A. rostratus in relation to depth in NW Mediterranean waters. Of the biochemical markers examined, acetylcholinesterase (AChE) and lactate dehydrogenase (LDH) activities and lipid peroxidation (LP) levels, only LP showed significant differences between depths. A positive relationship was found between AChE activity and Tetraphyllidea fam. gen. sp., Anisakis physeteris and H. aduncum abundance and a negative one with the abundance of Cucullaninae gen. sp. LDH showed a positive relationship with the abundance of the parasites Paracyclocotyla cherbonnieri and Tetraphyllidea fam. gen. sp. At cyto-histological level, coccidians were detected in the pyloric caeca with a prevalence of 90% in Barcelona, but in the rest of organs almost no alterations were detected. The restricted macroplanktonic diet of A. rostratus, that maintains it distant from the sea-floor for longer periods

Parasite communities of three abundant benthopelagic macrourid species (Hymenocephalus italicus, Nezumia aequalis and Trachyrincus scabrus) of the upper slope from the western Mediterranean were analysed seasonally. Histopathological, dietary and environmental information (temperature, salinity, O2 and turbidity) were also obtained. The three fish hosts shared only three parasite species (the nematodes Raphidascaris macrouri and Hysterothylacium aduncum and the acanthocephalan Echinorhynchus trachyrinci). H. italicus, the most benthopelagic fish, showed low parasite richness and diversity. The highest total mean abundance of parasites was found in spring for H. italicus and T. scabrus, coinciding with the highest prevalence/abundance of the majority of parasites whereas parasites of N. aequalis exhibited the highest richness, mean abundance and diversity in winter. Parasites related with benthic or infaunal preys were linked to autumn and summer samples off Besós (Barcelona). Some parasites were also linked to high turbidity, which may be due to higher abundances of the intermediate hosts, such as near-bottom zooplaktonic or suprabenthic preys. Few histopathological alterations (e.g. cysts of unknown aetiology) were observed restricted to the two most benthic-feeding fish species inhabiting more closely the near-bottom/sediment level, especially in autumn. © 2015 Elsevier Ltd.

The European hake is a top predator which first feeding preferences are largely unknown, despite being suspected that certain prey species and sizes are preferred. This knowledge is relevant for exogenous hatchery food supply during early life stages of hake, but remains elusive due to the difficulty of maintaining, spawning and harvesting hakes (Iglesias et al. 2010) to properly test its natural diets. Post-hatching early stages of hake are believed to feed at low light intensities associated to the deep water column, so testing parallel experimental designs of light-intensity vs. preys are key to undertake this species’ domestication. We examined in vitro prey preference, prey density and mortality of starved 7-8 DPH hake larvae under 12 zooplankton-based diets.

Optimal light characteristics are species-specific in aquatic environment. Each species needs a minimal threshold intensity to develop normally and grow, which is probably related to the aptitude to localize and catch preys. The synergistic effect of food availability-day-length appears to be determining at this stage. Long day-length stimulates growth, influences early maturation and improves larval rearing quality. However, a few species are able to develop and grow at very low light intensities or in the absence of light (Boeuf & Le Bailr 1999). In this study we tested feeding efficiency of hake larvae under various light conditions and tank background.

The European hake is a top predator which first feeding preferences are largely unknown, despite being suspected that certain prey species and sizes are preferred. This knowledge is relevant for exogenous hatchery food supply during early life stages of hake, but remains elusive due to the difficulty of maintaining, spawning and harvesting hakes (Iglesias et al. 2010) to properly test its natural diets. Post-hatching early stages of hake are believed to feed at low light intensities associated to the deep water column, so testing parallel experimental designs of light-intensity vs. preys are key to undertake this species’ domestication. We examined in vitro prey preference, prey density and mortality of starved 7-8 DPH hake larvae under 12 zooplankton-based diets.

A new amoeba species pathogenic for Senegalese sole is described based on ultrastructural analysis and SSU rDNA phylogenetic inference. The parasite presents round to ovoid trophozoites (<5 ¿m) with a high degree of intracellular simplification. No mitochondria were observed, but mitosome-like organelles were present. No cysts could be detected. Phylogenetic analysis confirmed the Senegalese sole parasite as an amitochondriate Archamoeba related to Endolimax nana and Iodamoeba spp., and we tentatively describe it as a new species in the genus Endolimax, Endolimax piscium. However, the genetic distance with E. nana is quite large, with only 60% pairwise identity between both SSU rDNA genotypes. Although the overall topology of the Archamoebae cladograms containing E. piscium was consistent, the support for the branching of Endolimax spp. relative to its closest neighbours was variable, being higher with distance or parsimony-based inference methods than with ML or Bayesian trees. The use of stringent alignment sampling masks also caused instability and reduced support for some branches, including the monophyly of Endolimax spp. in the most conservative data sets. The characterization of other Archamoebae parasitizing fish could help to clarify the status of E. piscium and to interpret the large genetic distance observed between Endolimax species.

The common mora, Mora moro (Risso, 1810) (Gadiformes, Moridae), is a cosmopolitan bathypelagic species of moderate commercial interest. Its usual bathymetric distribution in the western Mediterranean ranges between 800 and 1,500 m and in the Catalan Sea, M. moro is one of the main contributors to biomass at depths of 1,000-1,400 m. Although a number of studies exist on M. moro bathymetric distribution and depth-related trends, information on its parasites, diet and histological characteristics is very scarce and to the best of our knowledge no data exist on its parasite communities. A total of 62 specimens of M. moro were collected in 2010-2011 using a bottom trawl in two seasons and three localities of the Balearic Sea (NW Mediterranean Sea) at depths between 1,000 and 1,400 m. Parasitological, dietary (to prey-species level), enzymatic indicators of stress and histological data were obtained, alongside with environmental information (T, S, O2). The relationships among fish parasite load, condition indices, diet, enzymatic activity of muscular acetylcholinesterase (AChE) and lactate dehydrogenase (LDH), intensity of splenic melano-macrophage centres (MMC) and hepatic granulomas were tested. Detailed relationships were found between parasite taxa and prey ingested (e.g. Anisakidae gen. sp. related with meso-bathypelagic crustaceans; Anisakis Type I with benthopelagic squids), increasing our understanding of the parasites life cycles. Most parasites were linked to samples with highest levels of near-bottom O2, which enhances higher zooplankton biomass, higher food availability for M. moro and, likely, higher parasite infection via prey ingestion. Total parasite abundance and the abundance of Tetraphyllidea fam. gen. sp. showed a significant relationship with the activity of AChE and the abundance of Anisakis Type II with LDH activity. These results could suggest that fish with reduced stress levels, as suggested by enzymatic markers, host more abundant and diverse pa

Alepocephalus rostratus Risso, 1820 is the second most important fish species, in terms of biomass, inhabiting the deep slope of the Catalan Sea. However, its parasitic fauna remains understudied. In July 2010, specimens of A. rostratus (n=82) were collected on board the R/V García del Cid in the Catalan Sea (Western Mediterranean) with a semi-balloon otter-trawl (OTSB-14). A subsample of 10 individuals within this load was exclusively devoted to histopathological analyses. A portion of musculature of fishes was taken for biochemical markers determination. Environmental parameters (temperature in °C, salinity in psu, oxygen concentration in ml*l-1 and turbidity in voltage units) were recorded with a SBE25 CTD profiler at 5 m above the bottom. Eight different parasite species were found: 1 digenean, 1 monogenean, 1 cestode, 4 nematodes and 1 coccidian. Four of the seven metazoan taxa were larval forms, which combined with low parasite richness, correspond to a parasitic fauna pattern more typical of a bathypelagic fish species rather than a demersal one. The larvae Tetraphyllidea indet. (Scolex pleuronectis Müller, 1788) and Cucullaninae gen. sp. were the predominant species. Differences in abundance along depth were found mainly for the nematodes Cucullaninae gen. sp. and Hysterothylacium aduncum (Rudolphi, 1802). The former was found in higher numbers at lower depths, meanwhile the latter increased its abundance at greater depths. Both may indicate a shift in A. rostratus diet due to food scarcity at increasing depths. Cucullaninae gen. sp. was also related to high water turbidity, which may be related to high proliferation of one of its possible intermediate hosts (calanoid copepods), which in turn allow the high infection rates at these waters. Five of the metazoan parasites could be related to alterations in A. rostratus muscular enzymatic activity. Scolex pleuronectis, AnisakisType II and H. aduncum infections were associated with lower activity of acetylcholin

Specimens of Mora moro were collected in two seasons and three localities of the Balearic Sea (NW Mediterranean Sea) and parasitological, dietary (to prey-species level), enzymatic and histological data were obtained, alongside with environmental information (T, S, O2). The relationships among fish parasite load, condition indices, diet, enzymatic activity of muscular acetylcholinesterase (AChE) and lactate dehydrogenase (LDH), intensity of splenic melano-macrophage centres (MMC) and hepatic granulomas were tested. M. moro showed a rich and abundant parasite fauna, and was a new host record for 17 out of the 18 different endoparasite taxa found. Significant differences were detected among locality-season groups, in turn related to different environmental variables, for Anisakidae gen. sp., Anisakis Type II and Tetraphyllidea fam. gen. sp.; thus, they are proposed as potentially useful as biological tags for geographical discrimination of M. moro in the NW Mediterranean Sea. Detailed relationships were found between parasite taxa and prey ingested (e.g. Anisakidae gen. sp. related with meso-bathypelagic crustaceans; Anisakis Type I with benthopelagic squids). Most parasites were linked to samples with highest levels of near-bottom O2, which is consistent with direct relationships found between near-bottom O2 and zooplankton biomass in the Balearic Basin. Total parasite abundance and the abundance of Tetraphyllidea fam. gen. sp. showed a significant relationship with the activity of AChE and the abundance of Anisakis Type II with LDH. AChE was associated with hepatosomatic index (HSI) and condition factor (K); LDH with gonadosomatic index (GSI), K and fish total length (TL). LDH activity showed differences among sampling groups. Splenic MMC and hepatic granulomas were not associated with fish parasite load. A positive relationship was found between MMC area and fish TL and LDH activity. © 2014 Elsevier Ltd.

Esta patología se caracteriza por la presencia de protuberancias que se evidencian a través de la piel de los peces afectados. Estas lesiones se corresponden con nódulos en el tejido muscular, que muestran un aspecto de absceso. Lesiones similares a éstas también se han detectado en riñón, corazón, hígado y tracto digestivo, lo que nos permite definir la enfermedad como sistémica. Las secciones histológicas de los nódulos revelaron un extenso núcleo compuesto mayoritariamente por tejido necrótico rodeado por fibroblastos y macrófagos. Además, organismos plasmodiales de morfología esférica se encontraron en la capa externa de estos nódulos, normalmente en el interior de macrófagos o fibroblastos. Estos organismos también se observaron en la mucosa y submucosa intestinal, sin causar lesiones aparentes. En este trabajo se ha podido identificar a estos organismos como una nueva especie de ameba perteneciente a la familia Entamoebidae (Phylum Amebozoa, Infraphylum Archamoeba), y se describe tentativamente como una nueva especie del género Endolimax, Endolimax piscium n. sp. E. piscium presenta trofozoitos redondeados ( 5 μm) con un alto grado de simplificación intracelular, sin mitocondrias en el citoplasma pero con unos orgánulos compatibles con mitosomas. Con el fin de establecer técnicas fiables de diagnóstico para el reconocimiento de este parásito, se han desarrollado y evaluado técnicas específicas de hibridación in situ (ISH) y de reacción en cadena de la polimerasa (PCR), utilizando el examen histológico (una combinación de técnica histológica convencional en muestras de músculo e ISH en muestras de intestino) como prueba estándar para compararlos. Como resultado, todas las técnicas evaluadas obtuvieron altos indicadores de calidad. La técnica de ISH fue la más específica y sensible y se encontró particularmente útil como método de referencia de confirmación en muestras de intestino, no sólo para confirmar los positivos, sino también para descartar negativos, dia, A previously undescribed pathological condition is affecting the culture of Solea senegalensis in some farms of the Atlantic coast of Spain. This condition is characterised by the presence of external protuberances in the skin of the affected fish. These lesions correspond to nodules in the muscular tissue showing an abscess-like aspect. Similar lesions were found in kidney, heart, liver and the digestive tract, which leads us to define this pathology as a systemic disease. Histological sections of these nodules revealed the presence of a large core formed mainly of necrotic tissue surrounded with fibroblasts and macrophages. Round-shaped plasmodial organisms were found in the external layer of the nodules and usually inside macrophages or fibroblasts. These organisms were also observed in the intestinal mucosa and submucosa, without causing apparent lesions. This organisms are correspond to a new amoeba species, that belongs to the family Entamoebidae (Phylum Amebozoa, Infraphylum Archamoeba), and we tentatively describe it as a new species in the genus Endolimax, Endolimax piscium n. sp. E. piscium presents round to ovoid trophozoites ( 5 μm) with a high degree of intracellular simplification. No mitochondria were observed but mitosome-like organelles were present. In order to establish reliable diagnostic techniques for the recognition of E. piscium, specific in Situ Hybridization (ISH) and Polymerase Chain Reaction (PCR) tests have been developed and evaluated using the histological examination (a combination of conventional histological technique in muscle samples and ISH in intestine samples) as gold standard to compare them. As a result, all evaluated techniques obtain quite high quality indicators. The ISH technique was the most specific and sensitive and it was useful as a reference confirmatory method in intestine samples, not only to confirm positives but also to discard negatives, diagnosed as doubtful by conventional histology. PCR technique is a fast a