Reproductive ecology of Lophelia pertusa in Mingulay Reef and the Logachev mounds (North East Atlantic): a multi‐scale comparison

This paper presents the results of a multi-scale comparison in the reproductive stage of the cold-water coral Lophelia pertusa in two areas of the North-east Atlantic: The Mingulay Reef and the Logachev Mounds. The study was carried out during the Research cruise “Changing Oceans” on board of the RRV James Cook, conducted in May-June 2012. The comparative study between the two geographical areas revealed higher fecundity for the colonies analysed from Mingulay Reef compared to the colonies from the Logachev mounds. Moreover the development stage of the oocytes was more advanced in the colonies sampled from Mingulay than in the ones collected from Logachev. The comparison between single colonies and within the same colony from the Mingulay Reef did not show any differences in the maturity stage of the oocytes, nevertheless the analyses of the reproductive stage between mesenteries within the same polyps showed high variability, which indicates that the gametogenic development within each mesentery undergoes a prolonged period of oocyte production. This probably results in a protracted spawning period, which might improve the reproductive success of the species. This work has been developed under the framework of the UKOA program (United Kingdom Ocean Acidification program) and has been supported by the National Environmental Research Council (NERC, UK)

Reduced Antioxidant Response of the Fan Mussel Pinna nobilis Related to the Presence of Haplosporidium pinnae

The endemic fan mussel (Pinna nobilis) in the Mediterranean Sea is at high risk of disappearance due to massive mortality events. The aim of the study was to evaluate the antioxidant response of P. nobilis collected in the Balearic Islands (Western Mediterranean) before and after the mass mortality event. Individuals collected before (between 2011 and 2012) and after (between 2016 and 2017) the event were analyzed by histological, molecular, and biochemical methods to compare pathogenic loads and biochemical responses. All the individuals collected during 2016–2017 presented symptoms of the disease and were positive for Haplosporidium pinnae, while acid-fast bacteria or/and Gram-negative bacteria were detected in some individuals of both sampling periods. The activities of the antioxidant enzymes catalase and superoxide dismutase in the gills were significantly lower in P. nobilis a ected with the parasite compared to those in the asymptomatic ones, while levels of malondialdehyde, as an indicator of lipid peroxidation, were higher in infected individuals. When analyzing the di erential e ects of H. pinnae and Mycobacterium sp. on P. nobilis, it was observed that significant e ects on biomarkers were only observed in the presence of H. pinnae. Co-infection of P. nobilis by H. pinnae with other pathogens such as Mycobacterium sp. constitutes a serious problem due to its high mortality rate in the Balearic Island waters. This concerning situation for P. nobilis is favored by a reduction in antioxidant defenses related to H. pinnae infection that induces oxidative stress and cell damage.En prens

Food determines ephemerous and non-stable gut microbiome communities in juvenile wild and farmed Mediterranean fish

Novel insights were provided by contrasting the composition of wild and farmed fish gut microbiomes because the latter had essentially different environmental conditions from those in the wild. This was reflected in the gut microbiome of the wild Sparus aurata and Xyrichtys novacula studied here, which showed highly diverse microbial community structures, dominated by Proteobacteria, mostly related to an aerobic or microaerophilic metabolism, but with some common shared major species, such as Ralstonia sp. On the other hand, farmed non-fasted S. aurata individuals had a microbial structure that mirrored the microbial composition of their food source, which was most likely anaerobic, since several members of the genus Lactobacillus, probably revived from the feed and enriched in the gut, dominated the communities. The most striking observation was that after a short fasting period (86 h), farmed gilthead seabream almost lost their whole gut microbiome, and the resident community associated with the mucosa had a very much reduced diversity that was highly dominated by a single potentially aerobic species Micrococcus sp., closely related to M. flavus. The results pointed to the fact that, at least for the juvenile S. aurata studied, most of the microbes in the gut were transient and highly dependent on the feed source, and that only after fasting for at least 2 days could the resident microbiome in the intestinal mucosa be determined. Since an important role of this transient microbiome in relation to fish metabolism could not be discarded, the methodological approach needs to be well designed in order not to bias the results. The results have important implications for fish gut studies that could explain the diversity and occasional contradictory results published in relation to the stability of marine fish gut microbiomes, and might provide important information for feed formulation in the aquaculture industry.info:eu-repo/semantics/publishedVersio

Conocimiento objetivo y subjetivo de los consumidores españoles sobre el pescado

Product knowledge has been recognised as an important factor influencing consumer decision making. The aim of this study was to assess Spanish consumers’ knowledge about fish as well as their relationship with certain socio-demographic characteristics. Objective and subjective knowledge were measured by means of 5 and 4 items respectively. Overall results revealed the existence of a certain lack of knowledge about fish, although some differences were observed depending on gender, age, education level, region of residence and growing up region (coastal or interior). A positive relationship between objective and subjective knowledge was also detected

Wide-Geographic and Long-Term Analysis of the Role of Pathogens in the Decline of Pinna nobilis to Critically Endangered Species

A mass mortality event (MME) affecting the fan mussel Pinna nobilis was first detected in Spain in autumn 2016 and spread north- and eastward through the Mediterranean Sea. Various pathogens have been blamed for contributing to the MME, with emphasis in Haplosporidium pinnae, Mycobacterium sp. and Vibrio spp. In this study, samples from 762 fan mussels (necropsies from 263 individuals, mantle biopsies from 499) of various health conditions, with wide geographic and age range, taken before and during the MME spread from various environments along Mediterranean Sea, were used to assess the role of pathogens in the MME. The number of samples processed by both histological and molecular methods was 83. The most important factor playing a main role on the onset of the mass mortality of P. nobilis throughout the Mediterranean Sea was the infection by H. pinnae. It was the only non-detected pathogen before the MME while, during MME spreading, its prevalence was higher in sick and dead individuals than in asymptomatic ones, in MME-affected areas than in non-affected sites, and it was not associated with host size, infecting both juveniles and adults. Conversely, infection with mycobacteria was independent from the period (before or during MME), from the affection of the area by MME and from the host health condition, and it was associated with host size. Gram (-) bacteria neither appeared associated with MME.En prens

Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease

We identified rare coding variants associated with Alzheimer’s disease (AD) in a 3-stage case-control study of 85,133 subjects. In stage 1, 34,174 samples were genotyped using a whole-exome microarray. In stage 2, we tested associated variants (P<1×10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, an additional 14,997 samples were used to test the most significant stage 2 associations (P<5×10-8) using imputed genotypes. We observed 3 novel genome-wide significant (GWS) AD associated non-synonymous variants; a protective variant in PLCG2 (rs72824905/p.P522R, P=5.38×10-10, OR=0.68, MAFcases=0.0059, MAFcontrols=0.0093), a risk variant in ABI3 (rs616338/p.S209F, P=4.56×10-10, OR=1.43, MAFcases=0.011, MAFcontrols=0.008), and a novel GWS variant in TREM2 (rs143332484/p.R62H, P=1.55×10-14, OR=1.67, MAFcases=0.0143, MAFcontrols=0.0089), a known AD susceptibility gene. These protein-coding changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified AD risk genes. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to AD development

Ovary development of the red shrimp, Aristeus antennatus (Risso, 1816) from the Northwestern Mediterranean Sea

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