15 documents found, page 1 of 2
The effects of dissolved organic carbon on the reflex ventilatory responses of ...
Perry, Steve F.; Gilmour, Kathleen M.; Duarte, Rafael M. [UNESP]; Wood, Chris M.; Almeida-Val, Vera M.F.; Val, Adalberto L.Made available in DSpace on 2021-06-25T10:27:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-08-01; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Fundação de Amparo à Pesquisa do Estado do Amazonas; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Natural Sciences and Engineering Research Council of Canada; The tambaqui (Colossoma macropomum), migrates annua...
Mechanisms of ion transport in Potamotrygon, a stenohaline freshwater elasmobra...
Wood, Chris M.; Matsuo, Aline Y.O.; Gonzalez, Richard J.; Wilson, Rod W.; Patrick, Marjorie L.; Val, Adalberto LuisStingrays of the family Potamotrygonidae are the only stenohaline freshwater elasmobranchs. Potomotrygon sp. collected from the ion-poor blackwaters ([Na+], [Cl-] and [Ca2+]=10-30μmoll-1, pH6.1) of the Rio Negro, Amazonas, Brazil, were ammoniotelic (91% ammonia-N, 9% urea-N excretion) and exhibited blood chemistry (Na+, Cl-, urea, ammonia and glucose levels and osmolality) typical of freshwater teleosts. Unidir...
Corrigendum to “Nickel toxicity to cardinal tetra (Paracheirodon axelrodi) diff...
Holland, Aleicia; Wood, Chris M.; Smith, Donald Scott; Correia, Tiago Gabriel; Val, Adalberto LuisThe authors regret to inform that the following sentence has been misworded in the abstract. “Toxicity of Ni at pH 4 was negatively related to DOC concentration and amount of humic-like and fulvic-like DOC and positively related to fluorescence index.” should read “Toxicity of Ni at pH 4 was POSITIVELY related to DOC concentration and amount of humic-like and fulvic-like DOC and NEGATIVELY related to fluorescen...
Regulation of gill transcellular permeability and renal function during acute h...
Wood, Chris M.; Iftikar, Fathima I.; Scott, Graham R.; Boeck, Gudrun de; Sloman, Katherine A.; Matey, Victoria E.; Domingos, Fabíola Xochilt ValdezEarlier studies demonstrated that oscars, endemic to ion-poor Amazonian waters, are extremely hypoxia tolerant, and exhibit a marked reduction in active unidirectional Na+ uptake rate (measured directly) but unchanged net Na+ balance during acute exposure to low Po2, indicating a comparable reduction in whole body Na+ efflux rate. However, branchial O2 transfer factor does not fall. The present study focused on...
Effects of natural light and depth on rates of photo-oxidation of dissolved org...
Johannsson, Ora E.; Ferreira, Márcio Soares; Smith, David Scott; Crémazy, Anne; Wood, Chris M.; Val, Adalberto LuisSystems rich in terrigenous dissolved organic carbon (DOC), like the Rio Negro, can contribute significant amounts of carbon dioxide back to the atmosphere and support important microbial communities. We investigated photo-oxidation in the Rio Negro: (1) the depth to which light causes complete photo-oxidation to CO2 and changes in DOC structure, (2) the daily rate of change of absorbance indices, (3) the relat...
The osmorespiratory compromise: Physiological responses and tolerance to hypoxi...
Giacomin, Marina Mussoi; Bryant, Heather J.; Val, Adalberto Luis; Schulte, Patricia; Wood, Chris M.The characteristics of the fish gill that maximize gas exchange are the same that promote diffusion of ions and water to and from the environment; therefore, physiological trade-offs are likely to occur.Here, we investigated how salinity acclimation affects whole-animal respiratory gas exchange during hypoxia using Fundulus heteroclitus, a fish that inhabits salt marshes where salinity and oxygen levels vary gr...
Dissolved organic carbon from the upper Rio Negro protects zebrafish (Danio rer...
Duarte, Rafael Mendonça; Smith, Donald Scott; Val, Adalberto Luis; Wood, Chris M.The so-called â œ blackwatersâ of the Amazonian Rio Negro are rich in highly coloured dissolved organic carbon (DOC), but ion-poor and very acidic, conditions that would cause fatal ionoregulatory failure in most fish. However these blackwaters support 8% of the worldâ ™ s ichthyofauna. We tested the hypothesis that native DOC provides protection against ionoregulatory dysfunction in this extreme environment. D...
Metabolic fuel use after feeding in the zebrafish (Danio rerio): A respirometri...
Ferreira, Márcio Soares; Wood, Chris M.; Harter, Till S.; Pont, Giorgi Dal; Val, Adalberto Luis; Matthews, Philip G.D.We used respirometric theory and a new respirometry apparatus to assess, for the first time, the sequential oxidation of the major metabolic fuels during the post-prandial period (10 h) in adult zebrafish fed with commercial pellets (51% protein, 2.12% ration). Compared with a fasted group, fed fish presented peak increases of oxygen consumption (78%), and carbon dioxide (80%) and nitrogen excretion rates (338%...
Tribute to R. G. Boutilier: The effect of size on the physiological and behavio...
Sloman, Katherine A.; Wood, Chris M.; Scott, Graham R.; Wood, Sylvia; Kajimura, Makiko; Johannsson, Ora E.; Almeida-Val, Vera Maria FonsecaThe physiological and behavioural responses of two size groups of oscar (Astronotus ocellatus) to hypoxia were studied. The physiological responses were tested by measuring ṀO2 during decreasing environmental oxygen tensions. Larger oscars were better able to maintain oxygen consumption during a decrease in PO2, regulating routine ṀO2 to a significantly lower PO2 threshold (50 mmHg) than smaller oscars (70 mmHg...
Interactions between hypoxia tolerance and food deprivation in Amazonian oscars...
Boeck, Gudrun de; Wood, Chris M.; Iftikar, Fathima I.; Matey, Victoria E.; Scott, Graham R.; Sloman, Katherine A.; Nazar Paula da Silva, Maria deOscars are often subjected to a combination of low levels of oxygen and fasting during nest-guarding on Amazonian floodplains. We questioned whether this anorexia would aggravate the osmo-respiratory compromise. We compared fed and fasted oscars (1014 days) in both normoxia and hypoxia (1020 Torr, 4 h). Routine oxygen consumption rates (MO2) were increased by 75% in fasted fish, reflecting behavioural differenc...