Multidrug-resistant Escherichia coli strains isolated from swine manure biofertilizer in Brazil.

Escherichia coli is one of the key bacteria responsible for a variety of diseases in humans and livestock-associated infections around the globe. It is the leading cause of mortality in neonatal and weaned piglets in pig husbandry, causing diarrhea and significant harm to the industry. Furthermore, the frequent and intensive use of antimicrobials for the prevention of diseases, particularly gastrointestinal diseases, may promote the selection of multidrug-resistant (MDR) strains. These resistant genotypes can be transmitted through the excrement of animals, including swine. It is common practice to use porcine manure processed by biodigesters as fertilizer. This study aimed to examine the antimicrobial susceptibility, the presence of virulence genes frequently associated with pathotypes of intestinal pathogenic E. coli (InPEC), and antimicrobial resistance genes (ARGs) of 28 E. coli isolates collected from swine manure fertilizers. In addition, the enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) technique was used to investigate the genetic relationship among the strains. Using disk diffusion, the antimicrobial susceptibility profiles of the strains were determined. Using polymerase chain reaction (PCR), 14 distinct virulence genes associated with the most prevalent diarrhea and intestinal pathogenic E. coli (DEC/InPEC) and five ARGs were analyzed. All isolates tested positive for multidrug resistance. There was no detection of any of the 14 virulence genes associated with InPECs, indicating the presence of an avirulent commensal microbiota. Molecular classification by ERIC-PCR revealed that the majority of isolates (27 isolates) coalesced into a larger cluster with a genetic similarity of 47.7%; only one strain did not cluster in this cluster, indicating a high level of genetic diversity among the analyzed isolates. Thus, it is of the utmost importance to conduct epidemiological surveillance of animal breeding facilities in order to determine their microbiota and formulate plans to reduce the use of antimicrobials and improve animal welfare.

Sewage from a secondary hospital in Ribeirão Preto, southeastern Brazil: a source of multidrug-resistant Enterobacteriaceae.

Antimicrobial resistance is one of the severe threats to global health. Hospital sewage can serve as a reservoir for multi-resistant bacteria and promote the spread of antimicrobial resistance. This study aimed to investigate the antimicrobial susceptibility and the pathogenic potential of Enterobacteriaceae isolated from the sewage of a secondary hospital in Ribeirão Preto, a city in southeastern Brazil. The strains were isolated by membrane filtration and identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF). The antimicrobial susceptibility profile was performed by disk diffusion. Polymerase chain reaction (PCR) assays were used to detect virulence genes among the strains. Twenty-eight isolates were obtained, with Klebsiella pneumoniae being the predominant species (71.4%, n = 20). All isolates were classified as multidrug-resistant, including four isolates that were non-susceptible to at least 50% of the tested antibiotics. All isolates were also non-susceptible to cefuroxime and sulfonamides antibiotics; however, they were susceptible to norfloxacin, ofloxacin, amikacin, gentamicin, netilmicin, ertapenem, cefazolin, cefaclor, and cefotetan. The virulence genes ycfM, fimH, mrkD, kfu, and entB were detected in several isolates. Our study showed that even in a secondary hospital, without the routine of major surgeries and intensive care admissions, the hospital sewage can harbor a high percentage of multidrug-resistant bacteria with pathogenic potential. This leads to the worrying risk of public health and environmental contamination.

Multidrug-resistant and potentially pathogenic Enterobacteriaceae found in a tertiary hospital sewage in southeastern Brazil.

Hospital sewage is considered an environment with the potential to favor the spread and increase of multidrug-resistant bacteria (MDR). The increase in antimicrobial resistance is one of the greatest global threats today. Therefore, this study aimed to evaluate the profile of antimicrobial susceptibility and virulence factors in Enterobacteriaceae isolated from the sewage of a tertiary hospital located in southeastern Brazil. For bacterial isolation, membrane filtering, serial dilution, and spread-plate techniques were used. The bacterial isolates were identified using the MALDI-TOF (matrix-assisted laser desorption ionization-time of flight) technique. Antimicrobial susceptibility profile was performed by disk-diffusion test. Virulence genes were screened by Polymerase Chain Reaction (PCR) and the hypermucoviscosity phenotype by string test. In total, 13 enterobacteria distributed in three species were identified (Klebsiella pneumoniae, Escherichia coli, and Citrobacter freundii) and 76.9% (n = 10) were classified as MDR. Two K. pneumoniae demonstrated the hypermucoviscosity phenotype. The virulence genes ycfM and entB were detected in all K. pneumoniae isolates (other genes found were fimH, mrkD, and kfu). The results indicated that the sewage from the analyzed hospital receives MDR bacteria and has the potential to contaminate and spread through the environment.

Deltamethrin-induced nuclear erythrocyte alteration and damage to the gills and liver of Colossoma macropomum.

Deltamethrin is one of the most commonly used pyrethroids in the world, and it has a high toxic potential, mainly on aquatic organism. Thus, the purpose of this study was to evaluate LC50 values of deltamethrin on tambaqui (Colossoma macropomum) fingerlings and to investigate genotoxic effects and histopathological responses. Fish were exposed to different concentrations of deltamethrin (0, 6.16 × 10-3; 6.44 × 10-2; 1.34 × 10-1, and 1.93 × 10-1 mg L-1) for 96 h. In addition, a genotoxicity analysis was carried out on peripheral blood erythrocytes and histopathological changes were classified by the severity degree of damage and organ functioning. The 96 h LC50 value for tambaqui was estimated at 5.56 × 10-2 mg L-1 using a static test system. Nuclear abnormalities in exposed fish included micronuclei, blebbed, notched, 8-shaped, and binucleated nuclei forms. Deltamethrin significantly induced a notched nucleus compared to other abnormalities. A histopathological examination showed hepatic lesions and gill damage. Deltamethrin was found to be highly toxic; it induced genotoxicity and caused liver and gill inflammation in tambaqui.

Haematological assessment of four amazonian ornamental armoured catfish (Teleostei, Loricariidae) / Avaliação hematológica em quatro acaris ornamentais amazônicos (Teleostei, Loricariidae)

The aim of this study was to characterize the haematological profile of four Amazonian ornamentalfreshwater armoured catfish: acari-bola (Peckoltia oligospila - L06), acari-pleco (Cochliodon sp. - L145), acari-canoa(Lasiancistrus saetiger - L323) and acari-assacu (Pseudocanthicus spinosus - L160). The highest blood glucose levels(72.47 ± 28.7 mg dL-1) and erythrocyte counts (0.51 ± 0.2 x 106 cel. μL-1) were recorded for acari-canoa. Theacari-bola and acari-pleco presented similar concentrations of total plasma protein (TPP) (7.96 ± 1.8 and 7.93 ±1.8 g dL-1, respectively) against lower TPP concentrations observed in acari-canoa (4.87 ± 1.5 g dL-1) and acariassacu(6.55 ± 1.5 g dL-1). The acari-assacu had lower total haemoglobin concentration (5.88 ± 1.7 g dL-1) andhaematocrit (12.66 ± 4.6%). No interspecific differences were observed in mean corpuscular volume (MCV) andmean corpuscular haemoglobin concentration (MCHC). The acari-pleco and acari-assacu presented the highestcounts for neutrophils (4142.42 ± 3280.1 cel. μL-1) and thrombocytes (4778.33 ± 1224.8 cel. μL-1), respectively.The haematological profiles were similar to those reported in the literature for freshwater fish and the interspecificdifferences observed were discussed.

O objetivo deste estudo foi caracterizar os perfis hematológicos de quatro espécies de acarisornamentais da região amazônica: acari-bola (Peckoltia oligospila - L06), acari-pleco (Cochliodon sp. - L145), acaricanoa(Lasiancistrus saetiger - L323) e acari-assacu (Pseudocanthicus spinosus - L160). Os maiores níveis de glicose(72,47 ± 28,7 mg dL-1) e contagem de eritrócitos (0,51 ± 0,2 x 106 cel. μL-1) foram encontrados no acari-canoa. Oacari-bola e acari-pleco apresentaram concentrações semelhantes de proteína plasmática total (PPT) (7,96 ± 1,8 e7,93 ± 1,8 g dL-1, respectivamente) em oposição às menores concentrações de PPT no acari-canoa (4,87 ±1,5 g dL-1) e acari-assacu (6,55 ± 1,5 g dL-1). Essa última espécie apresentou menor concentração total dehemoglobina (5,88 ± 1,7 g dL-1) e hematócrito (12,66 ± 4,6%). Não foram observadas diferenças significativasentre as quatro espécies nos parâmetros volume corpuscular médio (VCM) e concentração de hemoglobinacorpuscular média (CHCM). O acari-pleco e o acari-assacu apresentaram os maiores valores de neutrófilos(4142,42 ± 3280,1 cel. μL-1) e de trombócitos (4778,33 ± 1224,8 cel. μL-1), respectivamente. Os perfishematológicos foram semelhantes aos relatados na literatura para peixes de água doce e as diferençasinterespecíficas observadas foram discutidas.

Essential oils of Varronia curassavica accessions have different activity against white spot disease in freshwater fish.

The aim of this study was to evaluate the antiprotozoal activity of essential oils from Varronia curassavica accessions against different stages of Ichthyophthirius multifiliis. Essential oils from each accession were tested in vitro at the concentrations 0, 10, 25, 50, 75, 100, and 200 mg/L. The VCUR-001, VCUR-202, VCUR-509, and VCUR-601 accessions presented the major compounds α-pinene, germacrene D-4-ol, (E)-caryophyllene and epiglobulol, and sabinene, respectively. These isolated compounds were tested in vitro at a concentration proportional to that found in the essential oil which caused 100% mortality of the parasite. The concentrations of 10 and 50 mg/L of the essential oil of accession VCUR-202 provided 100% mortality of trophonts and tomonts, respectively. For the accession VCUR-509, 100% mortality of trophonts and tomonts was observed at concentrations 75 and 200 mg/L of essential oil, respectively. The same mortality was observed at concentration 200 mg/L in both stages of the parasite for the other accessions. The major compounds α-pinene, sabinene, and the (E)-caryophyllene + epiglobulol mixture caused 100% mortality of trophonts and tomonts. The in vivo assay for white spot disease control was performed in a therapeutic bath of 1 h with the essential oil of accession VCUR-202 at concentrations of 0.5 and 2.0 mg/L. A significant reduction of about 30% of trophonts on infected fish was observed, independent of the oil concentration. The V. curassavica essential oil, especially the VCUR-202 accession, is a potential source of raw material for the formulation and commercialization of bioproducts to control freshwater white spot disease in fish.

Clove oil induces anaesthesia and blunts muscle contraction power in three Amazon fish species.

Clove oil is used as an anaesthetic for many species of fish worldwide; however, relatively few studies have assessed its effectiveness on Amazon fish species and no compelling evidence has ever been reported on the relaxant properties of this oil for skeletal muscle of fish. Thus, the objective of this study was to evaluate the latencies to deep anaesthesia and recovery, along with the myorelaxant effect of clove oil on three Amazon fish species: cardinal tetra, Paracheirodon axelrodi, banded cichlid, Heros severus and angelfish, Pterophyllum scalare, submitted to short-term anaesthetic baths. Fish were assayed in three groups of 60 fish each and individually anaesthetized in a completely randomized design with six clove oil concentrations using 10 fish/species/concentration. Electromyographic recordings from dorsal muscle were performed during stages of induction and recovery in which nine fish/species/stage were used. Deep anaesthesia was attained for all concentrations tested, and no mortalities were observed throughout the experiments and after a 48-h observation period. Concentration of 90 µL L-1 and above promoted fast deep anaesthesia (< 3 min) and calm recovery in angelfish and cardinal tetra, whereas the concentration of 60 µL L-1 sufficed to quickly anaesthetize banded cichlid. Times to full recovery were not significantly contrasting among species and occurred within appropriate time threshold (< 5 min). Clove oil exerted a conspicuous depression of muscle contraction power, and therefore can be effectively used as a muscle relaxant agent for P. scalare, P. axelrodi, H. severus and potentially, for other fish species.

Kudoa spp. (Myxozoa, Multivalvulida) parasitizing fish caught in Aracaju, Sergipe, Brazil / Kudoa spp. (Myxozoa, Multivalvulida) parasitando peixes capturados em Aracaju, Sergipe, Brasil

Abstract This study reports on Kudoa spp. (Myxozoa, Multivalvulida) from the fish species Lutjanus analis, Bagre marinus, Aspistor luniscutis and Lutjanus jocu, which were caught in Aracaju, state of Sergipe, Brazil. The parasites formed oval plasmodia around the esophagus of L. analis, and elongated plasmodia inside the skeletal muscle of B. marinus, A. luniscutis and L. jocu. Host myoliquefaction was not observed in all the cases studied. The current study provides a morphological and morphometric description of each parasite as well as a comparison with all the species described worldwide. Lack of molecular data impaired specific identification of the parasites. The importance of these parasites is discussed and the need for further studies on infections in Brazilian fish is emphasized because of the high economic impact of some Kudoa species which cause liquefaction in hosts’ muscles and render these fish unsuitable for consumption.

Resumo Este estudo relata Kudoa spp. (Myxozoa, Multivalvulida) de espécies de peixes Lutjanus analis, Bagre marinus, Aspistor luniscutis e Lutjanus jocu que foram capturados na costa litorânea de Aracaju, Estado de Sergipe, Brasil. Os parasitas formavam plasmódios ovais rodeando o esófago em L. analis, enquanto que nas espécies B. marinus, A. luniscutis e L. jocu formavam plasmódios alongados no interior das fibras musculares. Fenômenos de liquefação do músculo do hospedeiro não foram observados. O presente estudo proporciona uma descrição morfológica e morfométrica de cada parasita, sendo feita uma comparação com todas as espécies conhecidas em todo mundo. A inexistência de dados moleculares prejudica a identificação específica dos parasitas. A importância destes parasitas é discutida e a necessidade de mais estudos relacionados a infecções em peixes brasileiros é enfatizada por causa do alto impacto econômico de algumas espécies de Kudoa que causam liquefação nos músculos dos hospedeiros e tornam estes peixes impróprios para consumo.

Kudoa spp. (Myxozoa, Multivalvulida) parasitizing fish caught in Aracaju, Sergipe, Brazil.

This study reports on Kudoa spp. (Myxozoa, Multivalvulida) from the fish species Lutjanus analis, Bagre marinus, Aspistor luniscutis and Lutjanus jocu, which were caught in Aracaju, state of Sergipe, Brazil. The parasites formed oval plasmodia around the esophagus of L. analis, and elongated plasmodia inside the skeletal muscle of B. marinus, A. luniscutis and L. jocu. Host myoliquefaction was not observed in all the cases studied. The current study provides a morphological and morphometric description of each parasite as well as a comparison with all the species described worldwide. Lack of molecular data impaired specific identification of the parasites. The importance of these parasites is discussed and the need for further studies on infections in Brazilian fish is emphasized because of the high economic impact of some Kudoa species which cause liquefaction in hosts' muscles and render these fish unsuitable for consumption.

Feeding frequency on the production viability of production and quantitative descriptors of parasitism in angelfish / Frequência alimentar na viabilidade de produção e na descrição quantitativa de parasitas em acará bandeira

ABSTRACT: Angelfish (Pterophyllum scalare) is a very important species in Brazil's domestic market, however feeding managements differ from fish breeders to aquarists, so the cost of feed and labor become relevant items when cultivating the species. The objective of this research was to assess feeding frequency and feed deprivation based on growth performance, parasite infestation and cost-benefit in farming this species. The experiment was conducted in a completely randomized design in a 3x2 factorial scheme with 3 daily feeding levels, 4 meals, 2 meals and 1 meal; with and without feed deprivation and two repetitions. Feed deprivation consisted of offering feed 5 days a week only. Feeding twice a day without deprivation and four times a day with or without feed deprivation resulted in higher growth performance than feeding once a day. Monogenean and nematode parasitic loads were not influenced by feeding management. The cost-benefit analysis enabled us to observe that the treatment with the best benefit was the one involving two feedings a day with no deprivation. Thus, considering the parameters mentioned above, we concluded that the two daily feedings with no feed deprivation is the most adequate for farming this specie.

RESUMO: O acará bandeira (Pterophyllum scalare) é uma espécie muito importante no mercado interno do Brasil, no entanto o manejo alimentar difere entre os criadores de peixes para os aquaristas, levando em consideração o custo da alimentação e mão de obra. O objetivo deste trabalho foi avaliar o efeito da frequência de alimentação no desempenho na infestação do parasita e custo-benefício em acará bandeira de cultivo. O ensaio foi conduzido em um delineamento inteiramente casualizado em um esquema fatorial 3x2, sendo níveis de alimentação diários (4, 2 e 1 refeições) e 2 manejos (com e sem privação de alimentação), cada tratamento com duas repetições. Alimentação duas vezes por dia sem privação e quatro vezes por dia, com ou sem alimentação resultou no desempenho de crescimento, cargas parasitárias de monogeneas e nematoides não foram influenciados pelo manejo alimentar. A análise de custo-benefício nos permitiu observar que o tratamento envolvendo duas refeições por dia com nenhuma privação foi melhor. Conclui-se que o tratamento com duas refeições diárias sem privação alimentar é a mais adequada para o cultivo dessa espécie.

Crescimento de tambaqui em resposta a densidade de estocagem em tanques-rede / Tambaqui growth in response to stocking density in cages

The tambaqui Colossoma macropomum is rearing on different systems and environments and has shown good production in cages. The aim of this study was to evaluate the growth of tambaqui at different stocking densities in a lake supplied by rainwater and its effects on environmental quality. The experiment was conducted in consecutive phases: nursery at densities of 50, 100, 200 and 300 fingerlings m-3 and growth at densities of 20, 40 and 60 juveniles m-3. Water temperature, dissolved oxygen, pH and conductivity were monitored daily. Sediment and water samples were collected for analyses of nitrogen and phosphorus monthly. In the nursery, yield of 14,03 kg m-3 was significantly higher for fish at 300 fingerlings m-3. The highest weight gain was obtained at 50 fingerlings m-3. Survival over 97% was observed in the nursery. In the growth phase, weight gain and specific growth were inversely proportional to densities. Feed conversion and condition factor were not influenced by the evaluated densities. The density of 20 juveniles m-3 is more adequate to grow tambaqui in cages. Tambaqui cage culture did not alter the levels of nitrogen and phosphorus nutrients of lake water. Increased levels of organic matter, nitrogen and phosphorus in the sediment below the cages were verified without creating events of eutrophication. The results show that the tambaqui cage culture is viable in lakes provided with rainwater and can be integrated with multiple-use water services.

O tambaqui Colossoma macropomum é criado em diferentes sistemas e ambientes com boa produção em tanques-rede. O objetivo deste trabalho foi avaliar o crescimento do tambaqui em diferentes densidades de estocagem em tanques-rede em lago abastecido com água de chuva e seus efeitos sobre a qualidade ambiental. O experimento foi conduzido em fases consecutivas: recria nas densidades de 50, 100, 200 e 300 alevinos m-3 e terminação nas densidades de 20, 40, e 60 juvenis m-3. A temperatura da água, oxigênio dissolvido, pH e condutividade da água foram medidas diariamente. Amostras de sedimento e água foram coletadas para análise de nitrogênio e fósforo mensalmente. Na recria, a produção de 14,03 kg m-3 foi significativamente maior na densidade de 300 alevinos m-3. O maior peso final foi obtido na densidade de 50 alevinos m-3. A sobrevivência na recria foi superior a 97%. Na terminação, o ganho de peso e o crescimento específico foram inversamente proporcionais as densidades. A conversão alimentar e o fator de condição não foram influenciados pelas densidades testadas. A densidade de 20 juvenis m-3 é a mais adequada para a terminação de tambaquis em tanques-rede. A criação de tambaqui em tanques-rede não alterou os níveis de nitrogênio e fósforo da água do lago. Aumento dos teores de matéria orgânica, nitrogênio e fósforo foram verificados no sedimento abaixo dos tanques-rede, sem causar eventos de eutrofização. O presente estudo demonstrou que a criação de tambaquis em tanques-rede é viável em lagos abastecidos com água de chuva e pode integrar-se aos preceitos dos usos múltiplos da água.

Histopathological evaluation of seven Amazon species of freshwater ornamental armored catfish / Avaliação histopatológica em sete especies de cascudos ornamentais amazônicos

Fish commonly known as acaris or plecos are freshwater armored catfish economically important as a food resource and as ornamental fish. Most of these species are captured in the Amazon region. However, despite its economic importance, there is a lack of knowledge about their biological aspects. Thus, this study aimed to characterize and evaluate the histopathological aspects of important organs as gills, liver, integument and kidney of seven species of armored freshwater ornamental catfish from Guamá River, Pará State, Brazil. All organs showed typical characteristics of organs of other teleosts. In some species, gills and liver showed slight histopathological changes: telangiectasis, edema and morphological changes related to the presence of parasites (Monogenea and Digenea) in the gills, and changes in the arrangement of hepatocytes rows, and vacuolation of hepatocytes in the liver. Thus, the knowledge of the normal structure of organs and changes found can be used as tools for environmental and health monitoring of animals.

Os peixes conhecidos como Acaris ou Cascudos são siluriformes de água doce com o corpo revestido por placas ósseas, economicamente importantes como fonte de alimento e peixes ornamentais. A maioria destas espécies é capturada na região amazônica. Contudo, apesar de sua importância econômica, há desconhecimento sobre os aspectos biológicos desses peixes. Assim, o objetivo deste trabalho foi caracterizar e avaliar histologicamente órgãos importantes (brânquias, fígado, rim e tegumento) de sete espécies de peixes ornamentais de água doce do rio Guamá, Pará, Brasil. Todos os órgãos observados apresentaram as características típicas dos órgãos de teleósteos. Em algumas espécies, as brânquias e o fígado mostraram pequenas alterações histopatológicas: edema, telangiectasias e alterações morfológicas relacionadas com a presença de parasitas (Monogenea e Digenea) nas brânquias, e modificações no arranjo de linhas de cordões de hepatócitos e vacuolização destas células foram também observadas. Assim, o conhecimento da estrutura dos órgãos e as alterações encontradas podem ser utilizados como ferramentas para o monitoramento ambiental e sanitário dos animais.

Acute toxicity by water containing hexavalent or trivalent chromium in native Brazilian fish, Piaractus mesopotamicus: anatomopathological alterations and mortality.

This study evaluated the toxicity of hexavalent and trivalent compounds of chromium to the pacu, Piaractus mesopotamicus, in acute exposures of 96 h through mortality and histopathological responses. Hexavalent potassium dichromate was more toxic than trivalent compounds of chromium chloride, chromium oxide and chromium carbochelate. Sufficient mortalities occurred only with potassium dichromate to yield an LC50 value at 124.2 mg L(-1). Hexavalent chromium caused reversible and irreversible lesions, which may affect organ functionality. Histopathological evaluation showed that trivalent chromium caused lesions of lower severity. Pacu subjected to different concentrations of chromium carbochelate showed no histopathological changes in the kidneys, liver, skin and gills, being similar to those of the control fish. Among the three sources of Cr(3+), only chromium chloride at 200 mg L(-1) resulted in mortality, which reached 100 % within the first 18 h. These findings confirm that trivalent chromium, when administered within recommended levels, may be used safely in aquaculture.

Seasonality of nematode larvae in Iguanodectes spilurus (Characidae) an ornamental fish from northeastern Para, Brazil / Sazonalidade de larvas de nematóide em Iguanodectes spilurus (Characidae) um peixe ornamental no nordeste do Pará, Brasil

The current study presents a parasitological survey of larval nematodes from freshwater ornamental fish Iguanodectes spilurus caught in the watercourse of the Caete River, in the northeast region of the State of Para, Brazil. A total of 176 specimens, 1.36±0.75 g weight and 5.53±0.98 cm total length, were analyzed. Nematode larvae were identified as Capillaria sp., Procamallanus sp. and Anisakidae, with prevalence of 70.45% and infection intensity ranging from 1.81 to 4.70 larvae. The highest prevalence 57.38% occurred in the liver, but no seasonality was observed, indicating high infection throughout the year. Seasonality was observed in fish parasitized in the stomach, intestine and caecum, with prevalence and mean intensity of 17.61% and 2.32 parasites, 12.5% and 1.81 parasites, 10.79% and 2.21 parasites, respectively. The highest degree of infection was observed in the rainy season, probably due to increased availability of intermediate hosts or food.

O presente estudo apresenta um levantamento parasitológico de larvas de nematóides de Iguanodectes spilurus capturados no fluxo do Rio Caeté, nordeste do Pará, Brasil. Um total de 176 espécimes com médias de 1,36 ± 0,75 g de peso e 5,53 ± 0,98 cm de comprimento total foram analisados. Foram identificados em 124 peixes os nematóides Capillaria sp., Procamallanus sp. e da família Anisakidae, apresentaram uma prevalência de 70,45% e intensidade de infecção de 1,81 a 4,70 larvas. A maior prevalência foi de 57,38% no fígado, mas não foi observada sazonalidade, indicando alta potência de infecção ao longo do ano. A sazonalidade foi observada em peixes parasitados no intestino, estômago e ceco com prevalência e intensidade média de 17,61% e 2,32 parasitas, 12,5% e 1,81 parasitas, 10,79% e 2,21 parasitas, respectivamente. A maior infecção foi encontrada na estação chuvosa, provavelmente devido ao aumento da disponibilidade de hospedeiros intermediários ou de alimentos.

First occurrence of Quadrigyrus nickoli (Acanthocephala) in the ornamental fish Hyphessobrycon eques.

The objective of this work was to report the first seasonal occurrence of the acanthocephalan Quadrigyrus nickoli Schmidt & Hugghins, 1973 (Quadrigyridae), in the "Mato Grosso" Hyphessobrycon eques (Characidae) (Steindachner, 1882), collected from the Chumucuí River, state of Pará, Brazil. The fish were collected between July 2006 (rainy season) and June 2007 (dry season) and were examined for parasites using pattern techniques. A total of 75 parasites were found in the stomach and intestine. Among 83 fish examined (50 in the dry season and 33 in the rainy season), 22 were parasitized by cystacanths of Q. nickoli. The importance of H. eques as a paratenic host for Q. nickoli is discussed. This is the first study on the biology of and infection by Q. nickoli occurring in the eastern Amazon region.

Efeitos do tratamento com formalina e sulfato de cobre sobre os parâmetros hematológicos e parasitos monogenéticos em juvenis de Hemigrammus sp. (Osteichthyes: Characidae) / Evaluation of formalin and copper sulfate on monogenetic parasite (Urocleidoides sp.) of Hemigrammus sp. (Osteichthyes: Characidae) juveniles

The objective of this study was to evaluate the effectiveness of formalin and copper sulphate to controlm onogeneans injuvenile Hemigrammus spand its effect on leukocyte count. We used acompletely randomized design with five treatments and three replications. All treatments lasted for three days and consisted of: T1, control; T2 and T3 immersion bath for one hour in formalin, an of two concentrations of 0.25ml formalin and the other 0.1mlL-1; the T4 bath for 24 hours with 0,025 ml of formalin-L -1; and T5, bath 24 hours with copper sulphate (0.3 mgL-1). After the experimental period was observed that T2, 100% mortality. The T3 and T5 provided 100% efficiency, however, fish presented mortalities and intoxication of the 66 and 80% respectively. T4 showed an efficacy of 77.7% and decrease in parasitological indices: total number of parasites of 11, 3 ± 9, mean infection intensity of 3.2 ± 2 and a prevalence of 47.1%. As the leukocytes was observed that at T3, T4 and T5 occurred differences in the proportionof lymphocytes, monocytes and neutrophilsas compared to control. The CuSO4 and formalin reduce the parasite load, but presented to be toxicat higher concentrations.

O objetivo deste trabalho foi avaliar a eficácia da formalina e sulfato de cobre no controle de monogenéticos em juvenis de Hemigrammus sp e seu efeito na contagem diferencial de leucócitos. Utilizou-se um delineamento inteiramente casualizado com 5 tratamentos e 3 repetições. Todos os tratamentos tiveram duração de três dias e corresponderam a: T1, controle; T2 e T3 banho por imersão de uma hora em formalina, em duas concentrações uma de 0,25 ml e outra 0,1 ml formalina L-1; o T4, banho de 24 horas com 0,025 ml de formalina L-1; e o T5, banho de 24 horas com sulfato de cobre (0,3 mg L-1). Após o período experimental observou-se que em T2 ocorreu 100% de mortalidade. O T3 e T5 proporcionaram eficácia de 100%, porém os peixes apresentaram intoxicação e mortalidades de 66 e 80%, respectivamente. T4 apresentou eficácia de 77,7% e diminuição dos índices parasitológicos: número total de parasitos de 11,3± 9, intensidade média de infecção de 3,2± 2 e prevalência de 47,1%. Quanto aos leucócitos observou-se que no T3, T4 e T5 ocorreram diferenças na proporção de linfócitos, monócitos e neutrófilos em relação ao controle. O CuSO4 e a formalina reduzem a carga parasitária, mas apresentaram-se tóxicos nas maiores concentrações.

Parasites of four ornamental fish from the Chumucuí River (Bragança, Pará, Brazil).

The objective of the present study was to evaluate the parasite fauna of four species of ornamental fish collected in the Chumucuí River, municipality of Bragança, Pará, Brazil. From June 2006 to December 2007. Fishes (n=307) belonging to four species were collected, including 23 specimens of Moenkhausia sanctaefilomenae (redeye tetra), 37 Carnegiella strigata (marbled hatchetfish), 7 Chilodus punctatus (spotted headstander), and 240 Astyanax bimaculatus (twospot astyanax). The parasites found belonged to three taxa: monogeneans in the gills, nematodes (larvae of Capillaria sp. and Contracaecum sp.) in the digestive tract and liver and acanthocephalans (Quadrigyrus torquatus, Q. brasiliensis and Q. nickoli) in the stomach and intestine. Astyanax bimaculatus presented higher prevalence of acanthocephalans in the wet season, and lower prevalence of nematodes in the dry season. The possible importance of these parasites in the exportation of ornamental fish is discussed.

First occurrence of Quadrigyrus nickoli (Acanthocephala) in the ornamental fish Hyphessobrycon eques / Primeira ocorrência de Quadrigyrus nickoli (Acanthocephala) no peixe ornamental Hyphessobrycon eques

The objective of this work was to report the first seasonal occurrence of the acanthocephalan Quadrigyrus nickoli Schmidt & Hugghins, 1973 (Quadrigyridae), in the "Mato Grosso" Hyphessobrycon eques (Characidae) (Steindachner, 1882), collected from the Chumucuí River, state of Pará, Brazil. The fish were collected between July 2006 (rainy season) and June 2007 (dry season) and were examined for parasites using pattern techniques. A total of 75 parasites were found in the stomach and intestine. Among 83 fish examined (50 in the dry season and 33 in the rainy season), 22 were parasitized by cystacanths of Q. nickoli. The importance of H. eques as a paratenic host for Q. nickoli is discussed. This is the first study on the biology of and infection by Q. nickoli occurring in the eastern Amazon region.

O objetivo desse trabalho foi registrar a primeira ocorrência sazonal do acantocefala Quadrigyrus nickoli Schmidt & Hugghins, 1973 (Quadrigyridae) no peixe "Mato Grosso", Hyphessobrycon eques Steindachner, 1882 (Characidae), capturados no Rio Chumucuí, região Bragantina, Pará, Brasil. Os peixes foram coletados no período de julho∕2006 a junho∕2007 e examinados com técnica padrão para detecção de parasitas. Um total de 75 parasitas foram encontrados no estômago e intestino. Dos 83 peixes capturados (50 na estação seca e 33 na chuvosa), 22 estavam parasitados por cistacantos de Quadrigyrus nickoli. No presente trabalho discute-se a importância do H. eques como hospedeiro paratênico para Quadrigyrus nickoli. Os presentes dados constituem o primeiro estudo sobre a biologia e a infecção de Q. nickoli na Amazônia oriental.

Parasites of four ornamental fish from the Chumucuí River (Bragança, Pará, Brazil) / Parasitas de quatro peixes ornamentais do Rio Chumucuí (Bragança-Pará, Brasil)

The objective of the present study was to evaluate the parasite fauna of four species of ornamental fish collected in the Chumucuí River, municipality of Bragança, Pará, Brazil. From June 2006 to December 2007. Fishes (n=307) belonging to four species were collected, including 23 specimens of Moenkhausia sanctaefilomenae (redeye tetra), 37 Carnegiella strigata (marbled hatchetfish), 7 Chilodus punctatus (spotted headstander), and 240 Astyanax bimaculatus (twospot astyanax). The parasites found belonged to three taxa: monogeneans in the gills, nematodes (larvae of Capillaria sp. and Contracaecum sp.) in the digestive tract and liver and acanthocephalans (Quadrigyrus torquatus, Q. brasiliensis and Q. nickoli) in the stomach and intestine. Astyanax bimaculatus presented higher prevalence of acanthocephalans in the wet season, and lower prevalence of nematodes in the dry season. The possible importance of these parasites in the exportation of ornamental fish is discussed.

O objetivo do presente trabalho foi avaliar a fauna parasitária de quatro espécies de peixes ornamentais capturados no rio Chumucuí, no município de Bragança-PA. Foram coletados um total de 307 peixes pertencentes a 4 espécies, sendo elas: Moenkhausia sanctaefilomenae (olho de fogo, n = 23), Carnegiella strigata (borboleta, n = 37), Chilodus punctatus (cabeça-para-baixo, n = 7) e Astyanax bimaculatus (lambari, n = 240) coletados de junho de 2006 a dezembro de 2007. Foram observados 3 taxa parasitando os peixes: monogenéticos nas brânquias, nematóides (larvas de Capillaria sp. e Contracaecum sp.) no trato digestório e fígado e acantocéfalos (Quadrigyrus torquatus, Q. brasiliensis e Q. nickoli) no estômago e intestino. Astyanax bimaculatus apresentou maior prevalência de acantocéfalos na estação chuvosa, menor prevalência de nematóides na estação seca. Discute-se a eventual importância destes parasitas na exportação de peixes ornamentais.

Nematode parasites of Pescada Gó, Macrodon ancylodon Bloch and Schneider, 1801 (Osteichthyes, Sciaenidae), from Vila dos Pescadores, Bragança-PA, Brazil

The objective of this work was to evaluate the host/parasite relationship of nematodes in Macrodon ancylodon. Ninety seven fishes (50 in wet season and 47 in dry season) were weighed (167.1 ± 109.9g) and measured (28.3 ± 5.2cm). Only twelve specimens were not infected by any parasites and the prevalence of infection was 87.6%. The highest prevalence values were observed in August and September (dry season, 100%). The stomach was the most infected organ during the whole months (prevalence of 64.2%, and mean intensity of 4.6±7.8 parasites/fish), and the medium intestine showed the lowest infection (prevalence 27.3% and mean intensity 2.5±2.1 parasites/fish). The nematodes were identified as Raphidascaris sp., Goezia sp. and Cucullanus sp. Only the male and juvenile fishes could be presented different values of infection according to rainfall, being more infected in August to October. The female hosts presented higher values of abundance and mean intensity of infection (p<0.01) throughout the year.