Characterization of the peripheral thyroid system of gilthead seabream acclimated to different ambient salinities

Thyroid hormones are involved in many developmental and physiological processes, including osmoregulation. The regulation of the thyroid system by environmental salinity in the euryhaline gilthead seabream (Sparus aurata) is still poorly characterized. To this end seabreams were exposed to four different environmental salinities (5, 15, 40 and 55 ppt) for 14 days, and plasma free thyroid hormones (fT3, ff4), outer ring deiodination and Na+/K+ -ATPase activities in gills and kidney, as well as other osmoregulatory and metabolic parameters were measured. Low salinity conditions (5 ppt) elicited a significant increase in fT3 (29%) and ff4 (184%) plasma concentrations compared to control animals (acclimated to 40 ppt, natural salinity conditions in the Bay of Cadiz, Spain), while the amount of pituitary thyroid stimulating hormone subunit 13 (tshb) transcript abundance remained unchanged. In addition, plasma fT4 levels were positively correlated to renal and branchial deiodinase type 2 (dio2) mRNA expression. Gill and kidney T4-outer ring deiodination activities correlated positively with dio2 mRNA expression and the highest values were observed in fish acclimated to low salinities (5 and 15 ppt). The high salinity (55 ppt) exposure caused a significant increase in tshb expression (65%), but deiodinase gene expression (diol and dio2) and activity did not change and were similar to controls (40 ppt). In conclusion, acclimation to different salinities led to changes in the peripheral regulation of thyroid hormone metabolism in seabream. Therefore, thyroid hormones are involved in the regulation of ion transport and osmoregulatory physiology in this species. The conclusions derived from this study may also allow aquaculturists to modulate thyroid metabolism in seabream by adjusting culture salinity. (C) 2016 Elsevier Inc. All rights reserved.Socrates/Erasmus Grant from the European UnionUniversity of Cadiz [UCA 2009-074-FPI]Ministerio de Education y Ciencia, Spain [AGL2007-61211/ACU]FEDER, Spain [AGL2007-61211/ACU]Proyecto de Excelencia (Junta de Andalucia) [PO7-RNM-02843]Science Foundation (FCT) of Portugal [SFRH/BPD/89889/2012, SFRH/BPD/84033/2012]info:eu-repo/semantics/acceptedVersio

Factors driving bacterial microbiota of eggs from commercial hatcheries of european seabass and gilthead seabream

A comprehensive understanding of how bacterial community abundance changes in fishes during their lifecycle and the role of the microbiota on health and production is still lacking. From this perspective, the egg bacterial communities of two commercially farmed species, the European seabass (Dicentrarchus labrax) and the gilthead seabream (Sparus aurata), from different aquaculture sites were compared, and the potential effect of broodstock water microbiota and disinfectants on the egg microbiota was evaluated. Moreover, 16S ribosomal RNA gene sequencing was used to profile the bacterial communities of the eggs and broodstock water from three commercial hatcheries. Proteobacteria were the most common and dominant phyla across the samples (49.7% on average). Vibrio sp. was the most highly represented genus (7.1%), followed by Glaciecola (4.8%), Pseudoal-teromonas (4.4%), and Colwellia (4.2%), in eggs and water across the sites. Routinely used iodine-based disinfectants slightly reduced the eggs’ bacterial load but did not significantly change their composi-tion. Site, species, and type of sample (eggs or water) drove the microbial community structure and influenced microbiome functional profiles. The egg and seawater microbiome composition differed in abundance but shared similar functional profiles. The strong impact of site and species on egg bacterial communities indicates that disease management needs to be site-specific and highlights the need for species-and site-specific optimization of disinfection protocols. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Neurodegenerative diseases in the Estarreja (Central Portugal) inhabitants and their potential relationship with trace elements in the environment]

International audienc

Neurodegenerative diseases in the Estarreja (Central Portugal) inhabitants and their potential relationship with trace elements in the environment]

International audienc

Analysis of predisposition to neurodegenerative diseases related to the occurrence of potentially harmful metals in the environment

National audienc

Analysis of predisposition to neurodegenerative diseases related to the occurrence of potentially harmful metals in the environment

National audienc

Abelhas Euglossini (Apidae) de áreas de Mata Atlântica: abundância, riqueza e aspectos biológicos Euglossine bees (Apidae) from Atlantic Forest sites: abundance, richness, and biological aspects

<abstract language="eng">Collection data of Euglossinae males from Parque Estadual do Rio Doce (PERD) and Viçosa, both areas with remnants of Atlantic Rain Forest (Mata Atlântica) in Minas Gerais state, Brazil are presented. Comparisons made among three fragments with different sizes and states of disturbance from Viçosa showed differences in abundance of most common species and apparently, Eulaema nigrita Lepeletir, 1841 can be an useful indicator of disturbed sites. Some populations of euglossine bees seems to be restrict to a forest fragment, there being few or no flow of individuals or species of one fragment to another, even when they are only 1 km apart. 15 species of euglossines were sampled in PERD, and the most abundant was Eulaema cingulata (Fabricius, 1804). At Viçosa, 10 species were sampled, E. nigrita was the predominant one. Methyl salicylate attracted no males at both sites, in spite of large numbers of species and individuals sampled using this bait in other regions. The majority of species and individuals were collected in the rainy season. Only 0,58% of sampled males carried orchid pollinia (Catasetum Richard, Cycnoches Lindley and Coryanthes Hook) on their bodies. Emergence data of four species of Euglossa Latreille, 1802 reared from trap nests suggest that sex ratio in Euglossini is not a constant within the tribe. A list of 57 euglossine species now known to occur in Mata Atlântica are offered