Ultrastructure of intracytoplasmic Rickettsia-like infection of the gills of the teleost Archosargus probatocephalus (Sparidae) in northeastern Brazil / Ultraestrutura de Rickettsia intracitoplasmática infectando as brânquias do teleósteo Archosargus probatocephalus (Sparidae) no Nordeste do Brasil

Abstract A histopathological survey was conducted to investigate the presence of microparasites in fish Archosargus probatocephalus in a river near Maceió, Brazil. Light microscope observations of fragments of gill showed the presence of small cysts containing numerous myxospores that were morphologically identified as Henneguya. Transmission electron microscopy observations further revealed several gill cells containing groups of prokaryotic cells within large cytoplasmic vacuoles. Each infected host cell displayed a single vacuole containing a variable number of Rickettsia-like cells (up to 11), some of which presented the dumbbell shape characteristic of binary fission. The Rickettsia-like cells were pleomorphic, without a nucleus and with chromatin dispersed in the cytoplasm. They had a thin electron-dense wall of Gram-negative type. The morphology of these prokaryotic was similar to those of the order Rickettsiales and was described as a Rickettsia-like organism. Histopathological evaluation showed that several vacuole membranes had a lysed appearance. Some had ruptured, thus allowing direct contact between the Rickettsia-like organism and the cytoplasm of the host cell. The rupturing of the branchial epithelium may have contributed towards reduction of the surface area of the gills, but it is not possible to say that this was the cause of the host's death.

Resumo Um levantamento histopatológico foi realizado para pesquisar a presença de microparasitas, no peixe Archosargus probatocephalus, em um rio próximo a Maceió, Brasil. Observações ao microscópio óptico de fragmentos de brânquias mostraram a presença de pequenos cistos contendo numerosos mixósporos, identificados morfologicamente como Henneguya. Ocasionalmente, na microscopia eletrônica de transmissão, foram observados vários corpos citoplasmáticos de inclusão, grupo aparentemente de células procarióticas que vivem dentro de um grande vacúolo citoplasmático de algumas células branquiais. As células hospedeiras infectadas tinham um único vacúolo contendo um número variável de células do tipo Rickettsia, até 11, algumas das quais em forma do haltere, característica da fissão binária. Essas células eram pleomórficas sem núcleo, tendo a cromatina dispersa no citoplasma e possuíam uma parede densa de elétrons finos do tipo Gram-negativo. A morfologia dessas células procarióticas foi semelhante àquelas da ordem Rickettsiales e foram descritas como organismos tipo Rickettsiae. A histopatologia mostra várias membranas de vacúolos circundantes com aspetos lisados, enquanto outras apresentam rupturas que mostram contato direto do organismos tipo Rickettsiae com o citoplasma da célula hospedeira. A ruptura do epitélio branquial pode ter contribuído para a redução da superfície das brânquias, mas não é possível afirmar que foi a causa da morte do hospedeiro.

Draft genomes and reference transcriptomes extend the coding potential of the fish pathogen Piscirickettsia salmonis

Background: Draft and complete genome sequences from bacteria are key tools to understand genetic determinants involved in pathogenesis in several disease models. Piscirickettsia salmonis is a Gram-negative bacterium responsible for the Salmon Rickettsial Syndrome (SRS), a bacterial disease that threatens the sustainability of the Chilean salmon industry. In previous reports, complete and draft genome sequences have been generated and annotated. However, the lack of transcriptome data underestimates the genetic potential, does not provide information about transcriptional units and contributes to disseminate annotation errors. Results: Here we present the draft genome and transcriptome sequences of four P. salmonis strains. We have identified the transcriptional architecture of previously characterized virulence factors and trait-specific genes associated to cation uptake, metal efflux, antibiotic resistance, secretion systems and other virulence factors. Conclusions: This data has provided a refined genome annotation and also new insights on the transcriptional structures and coding potential of this fish pathogen.

Activity of Brazilian propolis against Aeromonas hydrophila and its effect on Nile tilapia growth, hematological and non-specific immune response under bacterial infection

ABSTRACT The effect of the ethanolic extract of propolis (EEP) on Aeromonas hydrophila was analyzed by determination of minimum inhibitory concentration (MIC). Then, the effects of crude propolis powder (CPP) on growth, hemato-immune parameters of the Nile tilapia, as well as its effects on resistance to A. hydrophila challenge were investigated. The CPP (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0%) was added to the diet of 280 Nile tilapia (50.0 ± 5.7 g fish-1). Hemato-immune parameters were analyzed before and after the bacterial challenge. Red blood cell, hematocrit, hemoglobin, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and hydrogen peroxide (H2O2) and nitric oxide (NO) were evaluated. The MIC of the EEP was 13% (v/v) with a bactericidal effect after 24 hours. Growth performance was significantly lower for those fish fed diets containing 2.5 and 3% of CPP compared to the control diet. Differences in CPP levels affected fish hemoglobin, neutrophils number and NO following the bacterial challenge. For others parameters no significant differences were observed. Our results show that although propolis has bactericidal properties in vitro, the addition of crude propolis powder to Nile tilapia extruded diets does not necessarily lead to an improvement of fish health.

New host record of five Flavobacterium species associated with tropical fresh water farmed fishes from North India

Abstract Yellow pigmented, filamentous, Gram-negative bacteria belonging to genus Flavobacterium are commonly associated with infections in stressed fish. In this study, inter-species diversity of Flavobacterium was studied in apparently healthy freshwater farmed fishes. For this, ninety one yellow pigmented bacteria were isolated from skin and gill samples (n = 38) of three farmed fish species i.e. Labeo rohita, Catla catla and Cyprinus carpio. Among them, only twelve bacterial isolates (13.18%) were identified as Flavobacterium spp. on the basis of morphological, biochemical tests, partial 16S rDNA gene sequencing and phylogenetic analysis. On the basis of 16S rDNA gene sequencing, all the 12 isolates were 97.6-100% similar to six different formally described species of genus Flavobacterium. The 16S rDNA based phylogenetic analysis grouped these strains into six different clades. Of the 12 isolates, six strains (Fl9S1-6) grouped with F. suncheonense, two strains (Fl6I2, Fl6I3) with F. indicum and the rest four strains (Fl1A1, Fl2G1, Fl3H1 and Fl10T1) clustered with F. aquaticum, F. granuli, F. hercynium and F. terrae, respectively. None of these species except, F. hercynium were previously reported from fish. All the isolated Flavobacterium species possessed the ability of adhesion and biofilm formation to colonize the external surface of healthy fish. The present study is the first record of tropical freshwater farmed fishes as hosts to five environmentally associated species of the Flavobacterium.

Use Carum copticum essential oil for controlling the Listeria monocytogenes growth in fish model system

This study was conducted to evaluate the antibacterial effect of Carum copticum essential oil (Ajowan EO) against Listeria monocytogenes in fish model system. Ajowan EO chemical composition was determined by gas chromatography/mass spectral analysis and the highest concentration of Carum copticum essential oil without any significant changes on sensory properties of kutum fish (Rutilus frisii kutum) was assigned. Then the inhibitory effect of Ajowan EO at different concentrations in presence of salt and smoke component was tested on L. monocytogenes growth in fish peptone broth (FPB), kutum broth and cold smoked kutum broth at 4 ºC for 12 days. Ajowan EO completely decreased the number of L. monocytogenes in FPB after 12 days of storage, however, antimicrobial effect of EO significantly reduced in kutum and cold smoked kutum broth. Addition of 4% NaCl and smoke component improved the anti-listerial activity of Ajowan EO in all fish model broths.

Enterobacteriaceae in some marine fish fillet

A total of 100 random samples of marine fish fillet represented by Epinephelus alexandrinus fillet, Dicentrachus labrax fillet, Stingray fish fillet and Scomberomorus commerson fillet [25 of each] were collected from different fish markets in Alexandria city. The sample weight was 100 grams. Each sample was kept in a separate sterile plastic bag and transferred in an ice box to the laboratory under complete aseptic conditions without undue delay. All collected samples were subjected to bacteriological examination for isolation and identification of Enterobacteriaceae. The results revealed that the total Enterobacteriaceae count in the examined samples of marine fish fillet were varied from 1.6 x 10[2] to 6.3 x 10[4] with an average of 2.1 x 10[4] + 3.1 x 10[3] cfu/g for Epinephelus alexandrinus fillet, 2.1 x 10[2] to 4.3 x 10[4] with an average of 9.1 x 10[3] + 1.1 x 10[3] cfu/g for Dicentrachus labrax fillet, 3.1 x 10[2] to 6.7 x 10[4] with an average of 1.3 x 10[4] + 7.3 x 10[3] cfu/g for Stingray fish fillet and 2.3 x 10[2] to 1.1 x 10[5] with an average of 6.3 x 10[4] + 5.2 x 10[3] cfu/g for Scomberomorus commerson fillet, respectively. Accurately, all examined samples [100%] out of Epinephelus alexandrinus fillet, Dicentrachus labrax fillet, Stingray fish fillet and Scomberomorus commerson fillet were contaminated with Enterobacteriaceae. Also, the total coliform count in the examined samples of marine fish fillet were ranged from 1.3 x 10 to 2.1 x 10[3] with a mean value of 9 x 10[2] + 7.5 x 10 cfu/g for Epinephelus alexandrinus fillet, 3.1 x 10 to 3.2 x 10[3] with a mean value of 1.1 x 10[3] + 2.3 x 10[2] cfu/g for Dicentrachus labrax fillet, 1.9 x 10 to 7 x 10[3] with a mean value of 2.6 x 10[3] + 1.6 x 10[2] cfu/g for Stingray fish fillet and 6 x 10 to 1.3 x 10[4] with a mean value of 6.4 x 10[3] + 7.1 x 10[2] cfu/g for Scomberomorus commerson fillet. The enteric bacteria isolated were Enterobacter aerogenes [44%] was the most frequent bacterial species isolated from Epinephelus alexandrinus fillet samples, followed by Proteus vulgaris [28%], Citrobacter diversus and Shigella species [20% of each] then Klebsiella ozanae and Provedencia spp [16% of each]. In regard to Dicentrachus labrax fillet samples, the most frequent bacterial species isolated was Enterobacter aerogens [40%], followed by Klebsiella peumoniae [32%], Citrobacter diversus[28%], Proteus vulgaris and Provedencia species [20% of each], Citrobacter freundii [16%] then Enterobacter cloacae, Klebsiella ozanae and Shigella species [12% of each]. Concerning Stingray fish fillet samples, Serratia liquifaciens [44%] represented the highest rate of isolation followed by Enterobacter aerogens and Enterobacter cloacae [36% of each], Citrobacter freundii [28%], Citrobacter diversus and Enterobacter cloacae [24% of each], Shigella species [20%] and Proteus vulgaris [16%]. On the other hand, Citrobacter freundii [28%], Enterobacter aerogens [24%], Proteus vulgaris [20%] then Klebsiella ozanae, Proteus rettgeri and Shigella species [12% of each] were isolated from the examined samples of Scomberomorus commerson fillet The Enteropathogenic Escherichia coli was isolated from 8%, 16%, 20% and 28% of the examined samples of Epinephelus alexandrinus fillet, Dicentrachus labrax fillet, Stingray fish fillet and Scomberomorus commerson fillet, respectively. Also, Salmonella species were recovered from 8%, 12% and 8% of the examined samples of Dicentrachus labrax fillet, Stingray fish fillet and Scomberomorus commerson fillet, respectively. The serotypes of Salmonella organisms isolated from Dicentrachus labrax fillet, Stingray fish fillet and Scomberomorus commerson fillet were S. enteritidis [4% for each] and S. Haifa [4% for each]. However, only one strain [4%] isolated from Stingray fish fillet were serologically identified as S. typhimurium. Enterobacteriaceae count, Coliform count, the isolated enteric bacteria, the isolated enteropathogenic E.coli and the isolated Salmonella organisms as well as the public health significance were discussed and the prophylactic measures to reduce the counts and the isolates in marine fish fillet were recommended

Bacterial infection of mudfish Clarias gariepinus (Siluriformes: Clariidae) fingerlings in tropical nursery ponds

Bacterial infection among the most common cultured mudfish Clarias gariepinus in Africa, has become a cause of concern, because it constitutes the largest economic loss in fish farms. In order to provide useful biological data of the pathogens for good management practices, samples were collected monthly between January 2008 and December 2009 in three monoculture nursery ponds, located in three different positions: upriver (A, grassland), mid-river (B, mixed forest and grassland) and downriver (C, rainforest) along 200km length of Cross River floodplains, Nigeria. A total of 720 fingerlings between 15.1 and 20.7g were analyzed to determine the degree of infection. The bacterial pathogens were taken from their external surfaces, and were isolated and identified by standard methods. The caudal fins of fingerlings from pond A had the highest bacterial load (5.8x10³cfu/g), while the least counts (1.2x103cfu/g) were identified on the head of fish from pond C, with Flexibacter columnaris as the major etiological agent. Pseudomonas fluorescens, Aeromonas hydrophila, Escherichia coli, Staphylococcus aureus and Micrococcus luteus were identified as co-isolates with P. fluorescens as dominant (0.7x10²cfu/mL) co-isolates in pond water. Clinical signs of five white spots with red periphery appeared on the external surface of infected fish. All the fish sampled, died after 4 to 9 days. There was no significant difference in the bacterial counts between different ponds, but the difference between fish organs/parts examined was significant. Fish from these ponds are therefore potentially dangerous to consumers and highly devalued, with the economic impact to producers. Preventive methods to avoid these infections are recommended. Rev. Biol. Trop. 59 (2): 751-759. Epub 2011 June 01.

Las infeccines bacterianas son comunes en el pez de cultivo Clarias gariepinus, el cual es el más cultivado en Africa y se han convertido en una causa de preocupación, ya que constituye la mayor pérdida económica en las granjas piscícolas. Se proporcionan datos biológicos de los agentes patógenos con el fin de proporcionar información útil para buenas prácticas de gestión en las granjas. Las muestras fueron recolectadas mensualmente entre Enero 2008 y Diciembre 2009 en tres viveros de estanques de monocultivo, situados en tres posiciones diferentes: río arriba (A, pastizales), mitad del río (B, bosque mixto y pastos) y aguas abajo (C, bosque) a lo largo de 200km de longitud en las llanuras de inundación del río Cross, Nigeria. Un total de 720 alevines de entre 15.1 y 20.7g fueron analizados para determinar el grado de infección. Los patógenos bacteriales fueron tomados de las superficies externas, y fueron aislados e identificados por métodos estándar. Las aletas caudales de los alevines del estanque A tuvieron la mayor carga bacteriana (5.8x10³cfu/g), mientras el menor conteo de bacterias (1.2x103cfu/g) fue identificado en la cabeza de los peces del estanque C, con Flexibacter columnaris como el agente etiológico más importante. Pseudomonas fluorescens, Aeromonas hydrophila, Escherichia coli, Staphylococcus aureus y Micrococcus luteus se identificaron como co-aislamientos con P. fluorescens, como dominantes (0.7x102cfu/mL) co-aislados en el agua del estanque. Los signos clínicos fueron cinco puntos blancos con la periferia roja y aparecieron en la superficie externa de los peces infectados. Todos los peces de la muestra, murieron después de 4 a 9 días. No hubo diferencia significativa en los recuentos bacterianos entre los diferentes estanques, pero la diferencia entre los órganos y las partes de los peces examinados fue significativa. Los peces de estos estanques son potencialmente peligrosos para los consumidores y con alta devaluación, ...

Molecular characterization of tetracycline- and quinolone-resistant Aeromonas salmonicida isolated in Korea

The antibiotic resistance of 16 Aeromonas (A.) salmonicida strains isolated from diseased fish and environmental samples in Korea from 2006 to 2009 were investigated in this study. Tetracycline or quinolone resistance was observed in eight and 16 of the isolates, respectively, based on the measured minimal inhibitory concentrations. Among the tetracycline-resistant strains, seven of the isolates harbored tetA gene and one isolate harbored tetE gene. Additionally, quinolone-resistance determining regions (QRDRs) consisting of the gyrA and parC genes were amplified and sequenced. Among the quinolone-resistant A. salmonicida strains, 15 harbored point mutations in the gyrA codon 83 which were responsible for the corresponding amino acid substitutions of Ser83-->Arg83 or Ser83-->Asn83. We detected no point mutations in other QRDRs, such as gyrA codons 87 and 92, and parC codons 80 and 84. Genetic similarity was assessed via pulsed-field gel electrophoresis, and the results indicated high clonality among the Korean antibiotic-resistant strains of A. salmonicida.

Isolation and experimental infection with Vibrio alginolyticus in the sea horse, Hippocampus reidi Ginsburg, 1933 (Osteichthyes: Syngnathidae) in Brazil / Isolamento e infecção experimental de Vibrio alginolyticus em cavalo-marinho, Hippocampus reidi Ginsburg, 1933 (Osteichthyes: Syngnathidae) no Brasil

The aim of this study was to evaluate the pathogenicity of Vibrio alginolyticus isolated from an outbreak of sea horse Hippocampus reidi reared in the State of Santa Catarina, Brazil, by experimental infection. Sea horses with necrosis on the mouth epithelium were collected from aquaria at the Aquaculture Department, UFSC and the bacterium isolated from the mouth, liver, heart and blood in tiosulphate citrate bilesalt sucrose agar broth. The strains were identified by API 20E kit with 99.1 percent probability as Vibrio alginolyticus. Twelve adult sea horses (9.63 ± 2.42 g and 15.12 ± 0.87 cm) were distributed in six aquaria of 10 L capacity with aerated sea water. Fish from three aquaria were submitted to an immersion bath in a solution containing 1.0 × 10(7) CFU of V. alginolyticus/mL for 15 minutes. Fish from the other three aquaria received the same procedure without bacteria. Twenty four hours after this challenge, 100 percent mortality was observed in the animals infected with V. alginolyticus. No mortality was observed in non-infected fish. Hyperplasia, displacement and fusion of secondary lamellae of the gills; leukocyte infiltration and necrotic foci in the kidney; hyperplasia, sinusoidal deformation and necrotic foci in the liver were observed in histopathological analysis. The V. alginolyticus isolated in this study was pathogenic to H. reidi and constitutes an important sanitary problem to its culture.

Foi avaliado por meio de infecção experimental a patogenicidade de Vibrio alginolyticus isolado de um surto de enfermidade em cavalo-marinho Hippocampus reidi cultivado no Estado de Santa Catarina, Brasil. Os peixes com necroses no epitélio bucal foram coletados em aquários do Departamento de Aquicultura, UFSC e as bactérias isoladas da boca, fígado, coração e sangue em meio Agar tiossulfato citrato bile sacarose. Os isolados foram identificados pelo kit API 20E como Vibrio alginolyticus com 99,1 por cento de probabilidade. Doze peixes adultos (9,63 ± 2,42 g e 15,12 ± 0,87 cm) foram distribuídos em seis aquários de 10 L com água marinha e aeração. Peixes de três aquários foram submetidos a um banho de imersão por 15 minutos em uma solução contendo 1,0 × 10(7) UFC de V. alginolyticus/mL. Nos outros três aquários realizou-se o mesmo procedimento sem a bactéria. Vinte e quatro horas após o desafio, 100 por cento de mortalidade foi observada nos animais infectados com V. alginolyticus. Não houve mortalidade nos peixes não infectados. Nas análises histopatológicas, foi observado hiperplasia, deslocamento do epitélio e fusão das lamelas secundárias das brânquias; infiltração de leucócitos e necrose no rim; hiperplasia, deformação sinusoidal e necrose no fígado nos animais desafiados com V. alginolyticus. O V. alginolyticus isolado neste estudo foi patogênico para H. reidi, constituindo-se de um importante problema para seu cultivo.

Isolation and characterization of Flavobacterium columnare (Bernardet et al. 2002) from four tropical fish species in Brazil / Isolamento e caracterização de Flavobacterium columnare de quatro espécies de peixes tropicais no Brasil

Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish, implicated in skin and gill disease, often causing high mortality. The aim of this study was the isolation and characterization of Flavobacterium columnare in tropical fish in Brazil. Piracanjuba (Brycon orbignyanus), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) and cascudo (Hypostomus plecostomus) were examined for external lesions showing signs of colunmaris disease such as greyish white spots, especially on the head, dorsal part and caudal fin of the fish. The sampling comprised 50 samples representing four different fish species selected for study. Samples for culture were obtained by skin and kidney scrapes with a sterile cotton swabs of columnaris disease fish and streaked onto Carlson and Pacha (1968) artificial culture medium (broth and solid) which were used for isolation. The strains in the liquid medium were Gram negative, long, filamentous, exhibited flexing movements (gliding motility), contained a large number of long slender bacteria and gathered into ‘columns'. Strains on the agar produced yellow-pale colonies, rather small, flat that had rhizoid edges. A total of four Flavobacterium columnare were isolated: 01 Brycon orbignyanus strain, 01 Piaractus mesopotamicus strain, 01 Colossoma macropomum strain, and 01 Hypostomus plecostomus strain. Biochemical characterization, with its absorption of Congo red dye, production of flexirubin-type pigments, H2S production and reduction of nitrates proved that the isolate could be classified as Flavobacterium columnare.

Flavobacterium columnare é o agente etiológico da columnariose em peixes de água doce, ocasionando enfermidade na pele e nas brânquias, provocando freqüentemente um grande número de mortalidade. O objetivo deste estudo foi o isolamento e a caracterização de Flavobacterium columnare em peixes tropicais no Brasil. Piracanjuba (Brycon orbignyanus), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) e cascudo (Hypostomus plecostomus) foram examinados externamente com relação a sinais característicos de columnariose, como manchas acinzentadas na cabeça, região dorsal e pedúnculo caudal dos peixes. A amostragem compreendeu a coleta de 50 exemplares de peixes, representando as quatro diferentes espécies escolhidas para este estudo. Amostras para o isolamento foram obtidas através de raspado com swab estéril das lesões e do rim dos peixes clinicamente diagnosticados como acometidos por columnarios e imediatamente semeados em meios de culturas artificiais (líquido e sólido) próprios para o estudo de Flavobacterium segundo Carlson e Pacha (1968). No meio líquido, houve o desenvolvimento de microrganismos que observados em gota pendente apresentaram a forma de bacilos finos, longos, móveis por deslizamento. Através da coloração de Gram, apresentaram morfologia de bacilos finos, Gram negativos, agrupados em colunas. Em meio sólido, as colônias eram pequenas, cinza-amareladas, com borda em forma de raiz. No total, foram obtidos quatro isolamentos: 01 cepa de Brycon orbignyanus; 01 cepa de Piaractus mesopotamicus; 01 cepa de Colossoma macropomum; e 01 cepa de Hypostomus plecostomus. A caracterização bioquímica das amostras, como absorção do vermelho Congo, produção de flexirrubina, produção de H2S e redução do nitrato, sugere que os isolamentos poderiam ser classificados como Flavobacterium columnare.

Edwardsiellosis in fish: a brief review.

Edwardsiellosis is one of the most important bacterial diseases in fish. Scientific work on this disease started more than forty years ago and numerous workers around the world are continually adding to the knowledge of the disease. In spite of this, not a single article that reviews the enormous scientific data thus generated is available in the English language. This article briefly discusses some of the recent research on edwardsiellosis, describing the pathogen's interaction with the host and environment, its pathogenesis and pathology as well as diagnostic, preventive and control measures.

Role of virulence plasmid of Aeromonas hydrophila in the pathogenesis of ulcerative disease syndrome in Clarias batrachus.

Pathogenic Aeromonas hydrophila (strain VB21), a multiple-drug resistance strain contains a plasmid of about 21 kb. After curing of plasmid, the isolates became sensitive to antimicrobials, to which they were earlier resistant. The cured bacteria exhibited significant alterations in their surface structure, growth profile and virulence properties, and failed to cause ulcerative disease syndrome (UDS) when injected into the Indian catfish Clarias batrachus. Routine biochemical studies revealed that the plasmid curing did not alter the biochemical properties of the bacteria. After transformation of the plasmid into cured A. hydrophila the bacterium regained its virulence properties and induced all the characteristic symptoms of UDS when injected into fish. Thus, the plasmid plays a pivotal role in the phenotype, growth and virulence of A. hydrophila and pathogenesis of aeromonad UDS.

Isolation and characterization of Streptococcus sp. from diseased flounder (Paralichthys olivaceus) in Jeju Island

Streptococcus sp. is gram-positive coccus that causes streptococcal infections in fish due to intensification of aquaculture and caused significant economic losses in fish farm industry. A streptococcal infection occurred from cultured diseased olive flounder (Paralichthys olivaceus) in May, 2005 at a fish farm in Jeju Island, Korea. The diseased flounder exhibited bilateral exophthalmic eyes and rotten gills; water temperature was 16~18oC when samples were collected. Of the 22 fish samples collected, 3 samples were identified as Lactococcus garvieae and 18 samples were identified as Streptococcus parauberis by culture-based, biochemical test. Serological methods such as slide agglutination, hemolysis and antimicrobial susceptibility test were also used as well as multiplex PCRbased method to simultaneously detect and confirm the pathogens involved in the infection. S. parauberis and L. garvieae have a target region of 700 and 1100 bp., respectively. One fish sample was not identified because of the difference in the different biochemical and serological tests and was negative in PCR assay. In the present study, it showed that S. parauberis was the dominant species that caused streptococcosis in the cultured diseased flounder.

Experimental evaluation of pathogenicity of Lactococcus garvieae in black rockfish (Sebastes schlegeli)

Black rockfish (Sebastes schlegeli) is an important mariculture species in Korea. The production of this fish is drastically declined due to bacterial diseases, particularly streptococcosis caused by Lactococcus garvieae. The bacterial surface characteristics of SJ7 and TY6 were found to have capsule but not NB13 and YS18. The experiential evaluation of L. garvieae pathogenicity, the capsular isolates showed high cumulative mortality i.e. SJ7 (100%) and TY6 (60%) compared to non-capsular isolates. Based on this result the capsular isolates L. garvieae were highly suspected as the causative agent of streptococcosis in rockfish.

Poder, Hierarquia e Reciprocidade: saúde e harmonia entre os Baniwa do Alto Rio Negro / Power, Hierarchy and Reciprocity: health and harmony among the Baniwa from the Upper Rio Negro

Resultado de ampla pesquisa na qual a autora apresenta os diversos aspectos que compõem o complexo mundo baniwa, a importância que a doença ocupa nele, suas especificidades, sua cultura, seu modo estóico de vida, suas inter-relações com outros grupos étnicos do Alto Rio Negro, Amazonas. Nos permite mergulhar e melhor compreender o 'caleidoscópio de problemas vividos hoje pelos povos indígenas' no Brasil em diversas áreas. Sociopoliticamente de alta relevância, revela a distância entre as necessidades desse povo e os serviços de saúde para eles disponibilizados, pautados por um tendência à uniformização e baixa sensibilidade às diferenças culturais. Transcende o contexto rionegrino, sendo relevante para o universo indígena como um todo. Academicamente instigante e politicamente perspicaz, inaugura nova coleção em grande estilo.

R-factor in Proteus vulgaris from ulcerative disease of fish, Channa punctatus.

A Proteus vulgaris isolated from external ulcers of the fresh water fish Channa punctatus showed multidrug resistance and heavy metal tolerance. The isolate from the ulcer showed resistance to chloramphenicol (Ch), nalidixic acid (Nx), streptomycin (Str) and tetracycline (Tet) with minimum inhibitory concentration (MIC) values of 750, 150, 75 and 125 microg/ml, respectively. The isolate showed growth in medium containing cadmium (Cd2+), up to a concentration of 2.5 mM indicating its heavy metal tolerance. Resistance to Ch, Str, Tet and Cd2+ of the isolate was lost after plasmid curing. Presence of plasmid DNA in the wild type and its absence in the cured P. vulgaris suggested that the resistance were plasmid mediated.

Doenças de peixes: profilaxia, diagnóstico e tratamento / Illnesses of fish: Prophylaxis, diagnosis and treatment

Publicada pela primeira vez em 1998, esta obra tem como objetivo divulgar, aos profissionais da piscicultura, informações básicas, e de certa maneira com caráter aplicado, sobre as doenças mais importantes que podem comprometer os peixes de água doce quando criados em cativeiro. Esta segunda edição tem algumas modificações em relação à anterior, embora mantenha a mesma organi-zação geral. A cultura de peixes marinhos é cada vez mais importante e, conquanto seja ainda incipiente no Brasil, terá sem dúvida, em médio prazo, uma relevância considerável. Assim, além de outras, foram também incluídas doenças que se manifestam nas pisciculturas marinhas, algumas de grande importância pelo impacto econômico que podem ter nessas explorações. Por outro lado, foram ampliadas as ilustrações fotográficas e incluídas inovações

Alteraçöes histológicas e comportamentais provocadas pela inoculaçäo de suspensäo bacteriana (Aeromonas hydrophila) em juvenis de Jundiá (Rhamdia quelen) / Histologycal and behavioral alterations induced by the inoculation of bacterial suspension (Aeromonas hydrophila) in Jundiá (Rhamdia quelen)

Com objetivo de avaliar as alteraçöes histológicas e comportamentais provocadas pela Aeromonas hydrophila em Rhamdia quelen, difeentes concentraçöes bacterianas (3,6 x 10(7) e 7,5 x 10(6)UFC - Unidade Formadora de Colônia/ml de soluçäo salina) foram inoculadas por via intramuscular. Para este estudo, foram utilizados 80 juvenis de jundiá com peso e comprimento de 16,55g e 13,23cm, respectivamente. Esses peixes foram mantidos durante 10 dias, em caixas d'água de 250 litros, com condiçöes iguais de temperatura, pH, alcalinidadee dureza. Os jundiás foram observados diariamente e, os moribundos, submetidos a cortes histológicos. Constatou-se entäo que a Aeromonas hydrophila causa perda de equilíbrio, apatia e exoftalmia, assim como alteraçöes histológicas na pele do tipo necrose, hemorragia e infiltrado inflamatório, atingindo tanto a camada da epiderme como da derme e musculatura.

Inoculaçäo bacteriana de Aeromonas hydrophila e a sobrevivência de juvenis de Jundiá, Rhamdia quelen (Teleostei: Pimelodida) / Inoculation with Aeromonas hydrophila bacteria and the survival of juvenile Jundiá, Rhamdia quelen (Teleostei: Pimelodida)

Visando a estudar a resistência do jundiá (Rhamdia quelen), é que se inoculou, por via intramuscular, as suspensöes de 1,3 x 10(9) e 3,5 x 10(8) UFC (Unidades Formadoras de Colônia) de Aeromonas hydrophila/ml de soluçäo salina. Dos 96 juvenis submetidos à inoculaçäo, distribuídos em seis caixas d'água de amianto, 32 constituíram o grupo controle, em que os animais foram injetados com soluçäo salina esterilizada. A partir do momento da inoculaçäo de 1ml do respectivo tratamento, foi observado que os peixes inoculados com a bactéria tiveram seu comportamento alterado, permaneceram estáticos no fundo da caixa e apresentaram 100 por cento de mortalidade em 24 horas. Os peixes do grupo controle injetados com salina näo apresentaram nenhuma anormalidade no comportamento. Sendo assim, é possível concluir que as concentraçöes 1,3 x 10(9) 3 3,5 x 10(8)UFC/ml de soluçäo salina säo letais para juvenis de jundiá.

Comparación entre el método estándar sugerido por APHA y los métodos Simplate y Petrifilm, para la identificación del grupo coliforme y de Escherichia coli en tilapia (Oreochromis sp) procedente de piscicultura de agua dulce / Comparison between the standard MPN method recommended by the American Public Health Association and the Simplate and Petrifilm methods for identification of the coliform group and Escherichia coli in tilapia (Oreochromis sp) originating from aquaculture in fresh water

We have compared three methods for the detection and quantification of coliforms and E. coli in fish: the conventional three-tube MNP method (APHA), the Simplate Method and the Petrifilm Method. Thirty samples of the tilapia's external surface (skin, gills and fin) produced in an artificial pond were collected. Samples were processed individually in buffered peptone water 1, then they were diluted and inoculated in Simplate, Petrifilm and LST tubes. Coliforms were isolated from 100 of the samples. The Simplate and 3M Petrifilm results were obtained after 24 h of incubation. The conventional three-tube MNP method showed results only after 96 hours of incubation. Simplate showed better recovery of coliforms and E. coli than 3 M Petrifilm and APHA method (P < 0.05). 3M Petrifilm and APHA were not significantly different for E. coli recovery.