Protozoários de vida livre em ambientes aquáticos do RN: ocorrência, caracterização e importância para a educação básica

Water is considered an essential right to life, besides being a determinant of economic development and social welfare, represented by both the quantity available, and the quality. In semi-arid Northeast, droughts occurring on a regular basis combined with human activities, aggravate the situation regarding the conservation of water resources in this area. To alleviate this condition is common to construction of artificial reservoirs, such as reservoirs and dams. As in natural aquatic environments, these reservoirs are potential sites for the proliferation, growth and development of diverse biological communities, whether of animals, plants and microorganisms. Research on the composition and ecology of these communities, especially microbial, are still restricted. One of the least studied groups in these environments are free-living protozoa, which over time have been neglected and after discoveries about its various functions in the aquatic ecosystem are beginning to receive more attention from scholars. They are, in quantitative terms, the most important consumers of microorganisms (mainly bacteria and algae) in aquatic environments, and therefore control the abundance of these. They may therefore influence the structure of the aquatic food chain in terms of species composition, abundance, biomass and biodiversity. Despite the recognition of the importance of protozoa in the final of the trophic transfer in aquatic environments, there are few data and, in general, are still precarious knowledge of them. Given the importance of protozoa in aquatic environments and the paucity of research on this group, especially in the state of Rio Grande do Norte, the present study aimed at identifying the genus and species of free-living protozoa that are present in the Armando Ribeiro Gonçalves Dam as well as to relate the occurrence and dynamics of the trophic conditions in the environment in which they are inserted, in order to support the hypothesis that species that are in these environments can serve to indicate the water quality. We observed the presence of 65 taxa of free-living protozoa, of which 29 were identified at the species level. There was a similarity space in taxonomic composition of protozoa, suggesting a possible regulation of this type of community for limnological variables other than those studied in this work (chlorophyll a, pH, temperature). Although it was aimed to analyze the conceptions of teachers and students from nearby towns Dam Armando Ribeiro Gonçalves, on issues relating to water quality and the role of protozoa. For this, we applied questionnaires with teachers and pupils of public schools of San Rafael and Itajá. It was concluded that teachers and students recognize the multi-dam Armando Ribeiro Gonçalves, although unaware of important aspects of the dynamics and ecology of this environment. Conceptions of teachers and students are matched at various times, especially with regard to waterborne diseases. In an attempt to identify possible misconceptions about the knowledge of the protozoa, assuming that these organisms have neglected their ecological role, and are seen as only, disease, a study was done with teachers and students, following a particular methodology that allowed look so clear and precise results. It was clear that knowledge about the free-living protozoa is still quite limited. The alternative conceptions that were found show a direct relation of protozoans and diseases. From the data obtained by these studies, we planned a series of science communication activities, environmental education and health education in schools close to study environments in order to promote a didactic transposition of accumulated knowledge about these organisms, favoring continuing education of teachers and the increase of information to the local community through the knowledge of biodiversity and ecology of these organisms. Moreover, the results found in this study and reflections on it that led to propose the elaboration of a book Readers with an emphasis on the group of freeliving protozoa in the populations for use in public schools in the region where it was developed the semiarid work

Biomonitoramento da qualidade da água e ações em educação ambiental em dois açudes da bacia hidrográfica Apodi-Mossoró, RN

Water scarcity is a reality for the inhabitants of the Brazilian semiarid region. The problem, in quantitative terms , is caused due to local climatic conditions due mostly to a water deficit. Qualitatively, results of multiple uses and resulting contamination by human activities. Eutrophication is presented as a threat to the sustainable use of water resources, in order to favor the predominance of dense populations of cyanobacteria, which can be potentially harmful to human health. The aim of this study is to understand the population dynamics of phytoplankton and cyanobacteria to assess water quality of reservoirs Santa Cruz do Apodi and Pau dos Ferros belonging to bacia Apodi Mossoró-RN . Water samples were collected monthly between October 2011 and May 2012 in reservoirs Santa Cruz do Apodi and Pau dos Ferros, in this latter , in Jan/12 we performed a diel profile . The abiotic variables obtained in the field and in the laboratory were: water temperature , dissolved oxygen , pH , turbidity , transparency , total nitrogen and total phosphorus . Phytoplankton samples were collected with a plankton net and bottle of Van dorn . Were performed : identification , quantification , calculation of biovolume , classification into functional groups and index calculation phytoplankton assembly ( Q ) , cyanotoxins were quantified by ELISA . Statistical analyzes supported the evaluation of the dynamics between biotic and abiotic factors. A questionnaire was conducted to examine the conceptions of the population, education professionals and students. The reservoir of Pau dos Ferros, shallow , turbid and eutrophic showed dominance of the functional group SN throughout the sample period . The phytoplankton biomass ranged from 20 to 70 mm ³ . L - 1, the lowest values coincided with the increase of the mixing zone and transparency, which contributed to the occurrence of a change in species composition phytoplankton . The application of the index Q proved relevant, the reservoir of Pau dos Ferros , depending on the species present , was classified ecologically as bad for almost the entire sample period . The reservoir Santa Cruz do Apodi showed low biomass ( 0.04 and 4.31 mm ³ . L - 1 ) and greater diversity in the phytoplankton composition . According to the index assembly (Q ), it showed moderate condition during most of the period influenced by different functional groups of typical meso- eutrophic environment (K S0, H1, C, F , J , E, D and N) . Associations of diatoms and green algae D and X1 succeeded populations of cyanobacteria in periods marked by greater instability in the system , caused by wind or rain. In summary , the occurrence of drought has a direct influence on the hydrological conditions of the reservoirs , in general, these events, reducing the reservoir level is directly related to decreased water quality and increased density of phytoplankton occurring predominance of cyanobacteria , the index Q reflected well to changes in phytoplankton composition , being a good indicator for biomonitoring of reservoirs in this study and survey of previous conceptions showed the need to work on environmental awareness for the preservation of water resources by conducting workshops for Environmental Education

Atividade antiinflamatória de uma heterofucana da alga marrom Padina gymnospora

Fucans, sulfated polysaccharides extracted from brown algae and some echinoderms, have been extensively studied for its diverse biological activities and because of its interference with molecular mechanisms of cell to cell recognition, including leukocyte trafficking from blood vessels into sites of inflammation mediated by selectin, a family of adhesion molecules. In the present study, we examined structural features of a heterofucan extracted from brown algae Padina gymnospora and its effect on the leukocyte migration to the peritoneum. The sulfated polysaccharides were extracted from the brown seaweed by proteolysis with the proteolytic enzyme maxatase. The presence of protein and uronic acid contamination was detected in the crude polysaccharide extract. Fractionation of the crude extract with growing concentrations of acetone produced five fractions with different concentrations of fucose, xylose, uronic acid, galactose, glucose and sulfate. The fraction precipitated with 1.5 volumes of acetone was characterized by infrared and nuclear magnetic resonance, through which can be observed the presence of sulfate groups in the C4 of -L-fucose. The anti-inflammatory action of this composite was assessed by a sodium thioglycollate-induced peritonitis assay and through nitric oxide production by the peritoneal macrophages using Griess reagent. Fraction F1.5 was efficient in reducing leukocyte influx into the peritoneal cavity when 10 mg/kg and 25mg/kg were used, resulting in a decrease of 56 and 39%, respectively. A decrease of nitric oxide production occurred when high concentrations of fucana were used. The cytotoxicity of the composite was also assessed using the reduction of 3-(4,5 dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT). Fraction F1.5 had no cytotoxicity when 500 μg/mL of the fraction was used. This study suggests the use of fraction F1.5 (heterofucan) as an anti-inflammatory

Mapeamento de recifes no Rio Grande do Norte: Touros e Macau/RN

Studies on the Brazilian continental shelf were developed between Touros and Macau-RN (NE Brazil) with the aim to mapping carbonate buildups, and especially, reef ecosystems. Remote sensing, submarine movies, bathymetric survey and diving were the methods used. This paper will focus on three main aspects of the Rio Grande do Norte reefs: 1) characterization of the coral fauna; 2) the classification and, 3) the distribution of the main northriograndense carbonate buildups. Reefs environments are found predominantly on the inner shelf adjacent to Touros, at depths shallower than 10 m. These reefs generally show NW-SE orientation parallel to the coastline and constitute groupings of knolls and patch reefs. A prominent carbonate buildup, where the corals are almost absents and algae incrustation is thin, occurs in average depths of 25 m, along the northern part of Rio Grande do Norte State and is classified as sandstone bank. Others sandstone banks, with smaller lengths and heights were mapped around 10 m depth. They should be related to an ancient coastline; however the corresponding litostratigraphic unit was not defined. This work is a contribution to the mapping of coral reef, in particular, and carbonate buildups, in general, on the Rio Grande do Norte coast

Caracterização dos sedimentos superficiais de fundo do complexo recifal de Maracajaú

The study carried out in the environment of Maracajaú reef an São Roque channel, had as main objective to analyze the characteristics of sediments active locally expressed in the grains, through collections of sediments in the field, technical processing and data analyzes of sediments. Data processing were made on three main aspects: biotic composition, concentration of calcium carbonate and particle size of the sediment. Differences between the sediments of the reefs and channel were observed. It was emphasized the contribution of algae limestone in the production of carbonate, with some influence of foraminifera near the coast. The particle size distribution presented significant results for the understanding of locally sedimentary deposits. The results showed an environment of carbonate, with predominance of algae limestone, associated to unconsolidated sediments with gross granularity, besides the presence of rhodoliths in all samples.The fragmentation of biotic components and the prevalence of elliptical rhodoliths with little or no branch, indicate an environment of high energy hydrodynamics. This work is a further contribution to the understanding of sedimentology active locally in reef environments, in particular the of Maracajaú reef, by virtue of their complex ecosystem composed of a diversity of wild fauna and flora that still little studied in Brazil comparing to accelerated growth of teeth extractions and usufructs of natural resources causing often irreversible impacts to the environment

Caracterização Morfodinâmica e Sedimentologia da Plataforma Continental Rasa na APA Estadual dos Recifes de Corais - RN

This study had to aimed to characterize the sediments of shallow continental shelf and realize the mapping of features visible for satellite images by using remote sensing techniques, digital image processing and analysis of bathymetry between Maxaranguape and Touros - RN. The study s area is located in the continental shallow shelf of Rio Grande do Norte, Brazil, and is part of the Environmental Protection Area (APA) of Coral Reefs. A total of 1186 sediment samples were collected using a dredge type van veen and positioning of the vessel was made out with the aid of a Garmin 520s. The samples were treated In the laboratory to analyze particle size of the sediment, concentration of calcium carbonate and biogenic composition. The digital images from the Landsat-5 TM were used to mapping of features. This stage was used the band 1 (0,45-1,52 μm) where the image were georeferenced, and then adjusting the histogram, giving a better view of feature bottom and contacts between different types of bottom. The results obtained from analysis of the sediment showed that the sediments of the continental shelf east of RN have a dominance of carbonate facies and a sand-gravelly bottom because the region is dominated by biogenic sediments, that are made mainly of calcareous algae. The bedform types identified and morphological features found were validated by bathymetric data and sediment samples examined. From the results obtained a division for the shelf under study is suggested, these regions being subdivided, in well characterized: (1) Turbid Zone, (2) Coral Patch Reefs Zone, (3) Mixed Sediments Carbonates Zone, ( 4) Algae Fouling Zone, (5) Alignment Rocky Zone, (6) Sand Waves Field (7) Deposit siliciclastic sands

Diagnosis of clinical bovine mastitis by fine needle aspiration followed by staining and scanning electron microscopy in a Prototheca zopfii outbreak

Biopsy by fine needle aspiration together with microbiological examination and scanning electron microscopy were evaluated in diagnosis of clinical bovine mastitis in a Prototheca zopfii outbreak. Fine needle aspiration was performed in 21 mammary quarters from ten Holstein cows presenting clinical mastitis caused by P. zopfii. The algae were previously identified in the microbiological examination of milk collected from these cows. Material aspirated from these 21 mammary glands was submitted to cytological staining (Gram, Giemsa and/or Shor staining). Fine needle aspiration enabled cytological identification of the algae in these 21 mammary glands, from which P. zopfii was isolated in the milk. Simultaneously, five mammary fragments collected by fine needle aspiration from these 21 mammary glands presenting clinical mastitis were also submitted to microbiological examination. P. zopfii was also isolated from these five fragments. Scanning electron microscopy technique also identified three of these five P. zopfii strains isolated from mammary fragments collected by cytological aspiration. These results suggest that fine needle aspiration may be an alternative method for the diagnosis of clinical mastitis.

Phenotypic and genotypic characterization of Prototheca zopfii in a dog with enteric signs

This is a case report of enteric protothecosis caused by Prototheca zopfii in an eight-year-old male mixed breed dog with a history of chronic bloody diarrhea, loss of appetite and weight loss. Algae were isolated from rectal scrapings in defibrinated sheep blood agar and dextrose Sabouraud agar. Cytological evaluation showed the presence of globular and cylindrical organisms with a defined capsule and variable number of endospores, characteristic of the genus Prototheca, in the rectum of the animal. Scanning electron microscopy of P. zopfii strains at different development stages confirmed the diagnosis of algal infection. Molecular identification using a conserved 18S rDNA gene sequence determined that the strain belonged to genotype 2. This report describes success on treatment of canine protothecosis, diagnosed based on clinical, cytological, microbiological, scanning electron microscopy and genotypical findings. (c) 2009 Elsevier Ltd. All rights reserved.

In vitro algaecide effect of sodium hypochlorite and iodine based antiseptics on Prototheca zopfii strains isolated from bovine milk

Prototheca zopfii has been considered one of the most important causes of environmental mastitis in Brazil. These algae are refractory to conventional therapy and cause great damage to the mammary gland. The present study evaluated the in vitro algaecide effect of sodium hypochlorite and iodine based antiseptics on 27 P. zopfii strains isolated from the milk of cattle. Low concentrations of sodium hypochlorite (0.0390625-0.15625%) and iodine (0.15625-0.625%) were effective against the isolates. These antiseptics may be recommended for hygiene routines, pre and postdipping and cauterization of bovine mammary glands infected by P. zopfii. (C) 2009 Elsevier Ltd. All rights reserved.

Alternative calcium source effects on commercial egg production and quality

This study aimed at verifying the possibility of replacing calcitic limestone by marine calcium in the diet of layers. A total number of 321 Hi-sex hens, with 40 weeks of age at the beginning of the experiment, was used. A completely randomized experimental design was applied, with 5 treatments (0, 15, 30, 45, and 60 % of calcitic limestone replacement by marine calcium source) and eight replicates of eight birds each. Treatments significantly affected specific gravity (p<0.05), with the inclusion of 60% marine calcium (T5) presenting the worst result as compared to T1, which included only calcitic limestone as calcium source. It was concluded that marine calcium can replace up to 45% of calcitic limestone with no effects on performance or egg quality.

Aquatic insects as the main food resource of fish the community in a Neotropical reservoir

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Larval development of Epialtus bituberculatus H. Milne Edwards, 1834 (Crustacea : Decapoda : Brachyura : Majidae) with comments on majid larvae from the southwestern Atlantic

The larval development of the spider crab Epialtus bituberculatus H. Milne Edwards which Lives on rocky shores with algae such as Sargassum and Hypneia, is described. Larvae were obtained from ovigerous females collected in Ubatuba, State of São Paulo, Brazil. Rearing was carried out at 24 +/- 1 degreesC, with an average salinity of 35 parts per thousand. Larval development consists of two zoeal stages and one megalopa. Zoeal development was completed in 9.5 days. Analysis indicated that zoeae of E. bituberculatus are very similar to those of E. brasiliensis Dana and Acanthonyx scutiformis (Dana). Differences noted between these species pertain to the setation of the carapace, maxillule and second maxilliped. The main morphological features useful for identification are presented together with a summary of features that characterize larvae of majid subfamilies in Brazil. A key for the identification of southwestern Atlantic majid zoeae to the family level is provided.

Phytoplankton composition, dominance and abundance as indicators of environmental compartmentalization in Jurumirim Reservoir (Paranapanema River), São Paulo, Brazil

Patterns in the spatial and temporal composition, dominance and abundance of the phytoplankton community of the Jurumirim Reservoir (Brazil) were studied during one year at ten different sampling stations. The main phytoplankton associations were characterized by diatoms and blue-green algae, in distinctive patterns of dominance. The main species were Microcystis aeruginosa Kuetz, Anabaena circinalis Rabenhorst, A. spiroides Kleb., A. solitaria Kleb., Aulacoseira cf. italica Grunow and A. granulata (Ehr.) Simon. A high growth of Aulacoseira was observed in the upstream zones of the reservoir in spring, at the beginning of the seasonal rainy period. This growth was a response to increased flow rates and input of fresh nutrients by the main feeder rivers. A high concentration of blue-green algae, especially Anabaena circinalis and A. spiroides, was observed in winter (dry season) in the lacustrine part of the reservoir, towards the dam. These algae benefitted from the longer water retention times and greater internal circulation of nutrients in the absence of a thermocline at this time of the year. Among the Cyanophyceae, there was an alternation between M. aeruginosa, more abundant in summer, and Anabaena, dominant in autumn and winter. A conspicuous growth of Anabaena occurred in a diverticle of the reservoir, sheltered from the main advective processes that predominate in the central channel. Higher phytoplankton diversity was associated with the contact zone between riverine and lacustrine systems.

The effect of the land use on phytoplankton assemblages of a Cerrado stream (Brazil)

OBJETIVO: Nosso objetivo foi investigar se o uso do solo do ambiente terrestre adjacente influencia a estrutura das assembleias fitoplanctônicas (composição, riqueza, diversidade e abundância) e biomassa (clorofila-a) em um riacho de Cerrado durante diferentes períodos do ano. MÉTODOS: Os trabalhos de campo foram realizados trimestralmente durante dois anos. RESULTADOS: As variáveis físico-químicas que melhor indicaram as diferenças nas condições da água foram condutividade, oxigênio dissolvido e transparência. Também houve um notável aumento na concentração de nitrogênio, fósforo e material em suspensão na água durante o verão devido aos efeitos da pluviosidade. As assembleias fitoplanctônicas foram compostas por 64 espécies. Cryptophyceae foi o grupo mais abundante, seguido por Bacillariophyceae. Para ambos os anos, a riqueza e a diversidade foram maiores durante a primavera e no outono, enquanto que a abundância do fitoplâncton e a concentração de clorofila-a foram mais elevados durante o outono e verão. A análise de agrupamento e a analise de correspondência canônica mostraram que a sazonalidade e o uso do solo são fatores importantes na estruturação das assembleias ao longo do ano. As alterações nas assembleias fitoplanctônicas ocorreram provavelmente em função da variação na intensidade e freqüência da mistura da água e da entrada de nutrientes oriundo do sistema terrestre adjacente para o aquático. CONCLUSÃO: A estrutura das assembleias fitoplanctônicas mostrou ser altamente influenciada pelo uso do solo, corroborando com a hipótese inicial do trabalho.

Can seasonal differences influence food web structure on preserved habitats? Responses from two Brazilian streams

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)