ABSTRACT
La presente comunicación proporciona información de la presencia en Perú de dos especies invasoras del género Ceratium: C. hirundinella (O.F. Müller) Dujardin y C. furcoides (Levander) Langhans. Se brinda información sobre la distribución de ambas especies en cuerpos de agua peruanos, así como datos de sus abundancias.
This works provides information on the presence in Peru of two invasive species of the genus Ceratium: C. hirundinella (O.F. Müller) Dujardin and C. furcoides (Levander) Langhans. Information is provided on the distribution of both species in Peruvian water bodies, as well as data on their abundance.
ABSTRACT
ABSTRACT: The dinoflagellate Piscinoodinium pillulare is a parasite with low parasitic specificity and unspecific geographical distribution. This research reported a simple and practical method - the principle of spontaneous sedimentation - to identify the presence of P. pillulare during massive infestations which does not require using precision equipment. Agitation in water of the gill arches of infested fish will elicit, after a period of rest, recording the accumulation of trophonts in the bottom of flasks. The method was applied during outbreaks of P. pillulare in tambaqui, Colossoma macropomum and matrinxã, Brycon amazonicus, in fish farms of the Amazon region and proved to be effective.
RESUMO: O dinoflagelado Piscinoodinium pillulare é um parasita com baixa especificidade parasitária e distribuição geográfica não específica. Este trabalho reporta um método simples e prático - o princípio da sedimentação espontânea - para identificar a presença de P. pillulare durante infestações maciças, que não requer o uso de equipamentos de precisão. A agitação em água dos arcos branquiais de peixes infestados permite, após um período de repouso, registrar o acúmulo de trofontes no fundo dos frascos. O método foi aplicado durante os surtos de P. pillulare em tambaqui, Colossoma macropomum e matrinxã, Brycon amazonicus, em pisciculturas comerciais da região Amazônica e provou ser eficaz.
ABSTRACT
The Phylum Protozoa brings together several organisms evolutionarily different that may act as ecto or endoparasites of fishes over the world being responsible for diseases, which, in turn, may lead to economical and social impacts in different countries. Apart from the recent advances for the diagnosis of fish diseases in Brazil, little is known on the protozoan parasites and their relationship with environment and host. This revision presents the most important protozoan parasites found in farmed fish from Brazil, not only with emphasis on its diagnosis, biology, transmission and host-parasite relationship, but also on some information that may be useful to researchers in determining the correct diagnosis in fish farms.
O filo Protozoa reúne diversos organismos evolutivamente distintos que podem atuar como ecto ou endoparasitos de peixes em todo o mundo, sendo responsáveis por doenças as quais, por sua vez, podem ocasionar impactos econômico e social nos diferentes países. Apesar dos recentes avanços no campo de diagnóstico de doenças em peixes no Brasil, ainda pouco se conhece sobre a fauna de protozoários parasitos de peixes e suas relações com o ambiente e hospedeiro. Esta revisão apresenta os mais importantes protozoários parasitos encontrados em peixes cultivados no Brasil, não apenas com ênfase no seu diagnóstico, biologia, transmissão e relação hospedeiro-parasito, mas também algumas informações que podem ser úteis para pesquisadores para o correto diagnóstico em pisciculturas.
Subject(s)
Animals , Protozoan Infections, Animal/diagnosis , Protozoan Infections, Animal/etiology , Protozoan Infections, Animal/prevention & control , Fish Diseases/parasitology , Fisheries , Brazil , Ciliophora Infections/diagnosis , Ciliophora Infections/etiology , Ciliophora Infections/veterinary , Fish Diseases/diagnosis , Fish Diseases/etiology , Fish Diseases/prevention & controlABSTRACT
Dinoflagellates of the genus Ceratium are generally marine organisms, but rare occurrences in freshwater have been observed in Brazil. In this paper we are recording for the first time the presence of Ceratium furcoides, an invasive species, in a shallow, natural intermittent pool formed at a high-altitude at the southern end of the Iron Quadrangle, an iron-mining district of Minas Gerais State (Southeast Brazil). Samples were collected in October and November of 2010 (rainy period). The population density of this organism observed in Lagoa Seca (“Dry Pool”) was very low, at most 4 ind L–1. Mountain lakes are extremely vulnerable to atmospheric deposition of organisms, making them valuable witnesses both of the many forms of impact arising from human activities and of the extended global connections that facilitate the dispersion and introduction of new species over great distances. Studies on the population dynamics of C. furcoides in natural tropical systems are still rare and very recent to the brazilian scenario and hence the monitoring of its dynamics and the potential impact on aquatic communities of its becoming established are essential to an understanding of the process of bioinvasion by this species.
Dinoflagelados do gênero Ceratium são principalmente marinhos, porém existem raras ocorrências em água doce no Brasil. Neste estudo registramos pela primeira vez a ocorrência de Ceratium furcoides, uma espécie invasora em um lago altitudinal natural raso localizado na porção sul do Quadrilátero Ferrífero, uma área de extração mineral no estado de Minas Gerais. As coletas foram realizadas nos meses de outubro e novembro de 2010 (período chuvoso). As densidades observadas para C. furcoides na Lagoa Seca foram muito baixas, com máximo de 4 ind L–1. Lagos de altitude são altamente vulneráveis à deposição atmosférica, o que os torna importantes testemunhos não só dos múltiplos impactos derivados de atividades humanas, mas também das extensas conexões globais, que acabam por facilitar a dispersão e introdução de espécies. Estudos sobre a dinâmica de C. furcoides em sistemas tropicais naturais ainda são escassos e por isso, o monitoramento de sua dinâmica e dos impactos potenciais em comunidades aquáticas a partir do seu estabelecimento, torna-se fundamental para o entendimento dos processos relacionados à bioinvasão desta espécie.
Subject(s)
Dinoflagellida/classification , Environmental Monitoring , Introduced Species , Altitude , Brazil , Lakes , Population DensityABSTRACT
En el presente trabajo se registra por primera vez al dinoflagelado potencialmente tóxico Alexandrium minutum Halim 1960 causante de las floraciones algales de marzo del 2006 y febrero del 2009, en el en el litoral del Callao, Perú. La identificación de A. minutum se realizó mediante un examen morfo-taxonómico detallando sus placas con microscopía de luz y epifluorescencia. Para su cuantificación se utilizaron cámaras de sedimentación. Nuestros resultados reportan por primera vez la presencia de A. minutum en el lado sudamericano del Pacífico, frente al Callao. Las características en tamaño, forma y morfología tecal que exhibieron los especímenes fueron muy similares a las descripciones clásicas de esta especie.
Herein, we report the first record of the potentially toxic dinoflagellate Alexandrium minutum Halim 1960 from the Peruvian littoral. Alexandrium minutum produced the algae bloom in March 2006 and February 2009, in the Callao bay. Its identification was carried out by a morpho-taxonomic examination, detailing their plates with light and epifluorescence microscopy, moreover its quantification was realized in sedimentation chambers. This is the first report of A. minutum for Southeast Pacific. The characteristics in size, shape and thecal morphology were similarly to original descriptions of this species.
ABSTRACT
This review briefly describes the origin, chemistry, molecular mechanism of action, pharmacology, toxicology, and ecotoxicology of palytoxin and its analogues. Palytoxin and its analogues are produced by marine dinoflagellates. Palytoxin is also produced by Zoanthids (i.e. Palythoa), and Cyanobacteria (Trichodesmium). Palytoxin is a very large, non-proteinaceous molecule with a complex chemical structure having both lipophilic and hydrophilic moieties. Palytoxin is one of the most potent marine toxins with an LD50 of 150 ng/kg body weight in mice exposed intravenously. Pharmacological and electrophysiological studies have demonstrated that palytoxin acts as a hemolysin and alters the function of excitable cells through multiple mechanisms of action. Palytoxin selectively binds to Na(+)/K(+)-ATPase with a Kd of 20 pM and transforms the pump into a channel permeable to monovalent cations with a single-channel conductance of 10 pS. This mechanism of action could have multiple effects on cells. Evaluation of palytoxin toxicity using various animal models revealed that palytoxin is an extremely potent neurotoxin following an intravenous, intraperitoneal, intramuscular, subcutaneous or intratracheal route of exposure. Palytoxin also causes non-lethal, yet serious toxic effects following dermal or ocular exposure. Most incidents of palytoxin poisoning have manifested after oral intake of contaminated seafood. Poisonings in humans have also been noted after inhalation, cutaneous/systemic exposures with direct contact of aerosolized seawater during Ostreopsis blooms and/or through maintaining aquaria containing Cnidarian zoanthids. Palytoxin has a strong potential for toxicity in humans and animals, and currently this toxin is of great concern worldwide.
Subject(s)
Animals , Dogs , Humans , Mice , Rabbits , Rats , Acrylamides , Chemistry , Toxicity , Anthozoa , Virulence , Physiology , Dinoflagellida , Virulence , Physiology , Guinea Pigs , Haplorhini , Lethal Dose 50 , Marine Toxins , Chemistry , Toxicity , Seaweed , Virulence , Physiology , Shellfish Poisoning , Sodium-Potassium-Exchanging ATPase , MetabolismABSTRACT
This study reports the occurrence and the effect of the environmental factors on the spatial and temporal distribution of the dinoflagellate Akashiwo sanguinea (Hirasaka) Hansen & Moestrup in estuarine waters of northeastern Brazil. Samples were collected at seven stations from March 2007 to February 2008 during high tide and low tide, using Van Dorn bottles. The samples were immediately fixed with Lugol and analyzed with the Utermöhl method. Water samples were also collected for the identification of the hydrological characteristics of the area. Akashiwo sanguinea occurred throughout the annual cycle and at all sampling sites with densities ranging between 5 and 410 x 103 cells.L–1. The highest densities were recorded at low tide, especially during the months of the rainy season (July: 210 x 103 cells.L–1; August: 410 x 103 cells.L–1). Density values were within the normal range and blooms were not detected. Despite being common in the area, the species showed preference for sites with high concentrations of orthophosphate and total dissolved phosphorus and with salinity in the mesohaline regime.
Este estudo relata a ocorrência e o efeito dos fatores ambientais na distribuição espacial e temporal do dinoflagelado Akashiwo sanguinea (Hirasaka) Hansen et Moestrup em águas estuarinas do Nordeste do Brasil. As amostras foram coletadas em sete estações, durante o período de março 2007 a fevereiro 2008 durante os regimes de preamar e baixa-mar, com o auxílio de garrafas tipo Van Dorn. As amostras foram imediatamente fixadas com lugol e analisadas pelo método de Utermöhl. Amostras de água foram também coletadas para a identificação das características hidrológicas da área. Akashiwo sanguinea ocorreu em todo o ciclo anual e em todos os locais de coleta com densidade variando de 5 a 410 cells.L–1 x 103, sendo as maiores densidades registradas na baixa-mar, principalmente, durante os meses do período chuvoso (julho 210 cells.L–1 x 103, agosto 410 cells.L–1 x 103). Os valores quantitativos estiveram dentro dos padrões normais, não tendo sido detectados florescimentos com conotações de blooms. Apesar de ser frequente na área, a espécie mostrou preferência pelos locais com maiores concentrações de ortofosfato dissolvido e fósforo total dissolvido e salinidade compreendida no regime mesoalino.
Subject(s)
Dinoflagellida/classification , Brazil , Estuaries , Environmental Monitoring/methods , Population Density , Population Dynamics , SeasonsABSTRACT
The genus Histioneis (=Parahistioneis) contains an excessive number of poorly described species, often based on the observation of a single specimen and ignoring the intraspecific variability. In order to investigate the validity of the species and to suggest synonyms, the original illustrations of all known species of Histioneis are reproduced and grouped based on the morphological similarity. The scarce records and the uncertainties on the identification at the species level are responsible of the lack of biogeographical information. Large and highly ornamented species tended to appear in tropical waters, whereas smaller and less ornamented species showed a wider distribution and they can also found in temperate waters such as the Mediterranean Sea. Rev. Biol. Trop. 55 (2): 459-477. Epub 2007 June, 29.
El género Histioneis (=Parahistioneis) tiene una cantidad excesiva de especies, descritas insuficientemente y a menudo a partir de un solo espécimen, ignorando la variabilidad intra-específica. Con el objetivo de investigar la validez de las especies y sugerir sinónimos, aquí se presentan las ilustraciones originales de Histioneis agrupadas según su parecido morfológico. Las escasas observaciones de Histioneis y las dudas en la identificación a nivel de especie son responsables de la falta de información sobre su distribución geográfica. Las especies de mayor tamaño y más ornamentadas son típicas de aguas tropicales. Las especies más pequeñas y menos ornamentadas presentan una distribución más amplia y pueden encontrarse también en aguas templadas, como el Mar Mediterráneo.