Motile aeromonad septicemia (MAS) at Cyprinus carpio L, 1758 (Actinopterygii: Cyprinidae) in Lake Tödürge (Sivas/Turkey) / [Septicemia móvel por aeromonada (SMA) em Cyprinus carpio L, 1758 (Actinopterygii: Cyprinidae) no lago Tödürge (Sivas, Turquia)]

In this study, fish's morphologic and anatomic lesions caused by motile aeromonad septicemia (MAS) depending on environmental stress in carp, Cyprinus carpio population living in Lake Tödürge were identified. Various morphological and anatomical deformations and lesions were observed in the body of approximately 17% (252 fish specimens) of a total of 1488 carp samples. Bacteria are grown from all wipe samples. Bacterial colonies have a gray-white appearance with round, convex and smooth edges. 15-20 cfu colonies were observed in each aerop culture. As a result of analysis of wet wipe samples from infected fish's skin, gill, kidney and liver, it is determined that the bacteria which causes septicemia is Aeromonas sobria from the Aeromonadaceae family (with 99.2% confidence value). No bacteria were grown in cultures except A. sobria. Some symptoms of the infection are inflammation on different parts of the fish bodies, eruption on skin and scales, dermal necrosis, degeneration at soft rays of the fins, exophthalmos, and purulent liquid accumulation in the abdominal cavity, etc. Infected fish were most commonly encountered in July and August (water temperature above 20ºC), the lowest in October and November (water temperature below 10ºC).(AU)

Neste estudo, foram identificadas lesões morfológicas e anatômicas causadas por septicemia móvel por aeromônios (MPA), dependendo do estresse ambiental da carpa, a população de Cyprinus carpio que vive no lago Tödürge foi identificada. Várias deformações e lesões morfológicas e anatômicas foram observadas no corpo de aproximadamente 17% (252 amostras de peixes) de um total de 1488 amostras de carpa. As bactérias são cultivadas a partir de todas as amostras de limpeza. As colônias bacterianas têm uma aparência branco-acinzentada, com bordas arredondadas, convexas e lisas. Foram observadas 15-20 colônias de UFC em cada cultura de aerop. Como resultado da análise de amostras de lenços umedecidos da pele, brânquias, rins e fígado de peixes infectados, é determinado que a bactéria que causa a septicemia é a Aeromonas sobria, da família Aeromonadaceae (com valor de confiança de 99,2%). Nenhuma bactéria foi cultivada em culturas, exceto A. sobria. Alguns sintomas da infecção são inflamação em diferentes partes dos corpos dos peixes, erupção na pele e escamas, necrose dérmica, degeneração aos raios moles das barbatanas, exoftalmia e acúmulo de líquido purulento na cavidade abdominal, entre outros. Os peixes infectados eram encontrados com maior frequência em julho e agosto (temperatura da água acima de 20ºC), e eram menos comumente encontrados em outubro e novembro (temperatura da água abaixo de 10ºC).(AU)

Characterization of mercury-resistant clinical Aeromonas species

Mercury-resistant Aeromonas strains isolated from diarrhea were studied. Resistance occurs via mercuric ion reduction but merA and merR genes were only detected in some strains using PCR and dot hybridization. Results indicate a high variability in mer operons in Aeromonas. To our knowledge, this is the first report of mercury-resistant clinical Aeromonas strains.

Development of duplex-PCR for identification of Aeromonas species

Introduction The number of reports of intestinal infections caused by Aeromonas spp. has increased significantly in recent years. In most clinical laboratories, identification of these bacteria is carried out by general phenotypic tests that sometimes do not accurately differentiate Aeromonas and Vibrio. Methods A duplex-polymerase chain reaction (PCR) was developed directed to 2 targets identifying Aeromonas spp. pathogenic to humans. Results The duplex-PCR results were reproducible and specific for Aeromonas spp. pathogenic to humans. Conclusions This method will allow differentiation between Vibrio and Aeromonas spp. in patients with in cholera-like symptoms and can also be used in water quality monitoring. .

Markers of pathogenicity islands in strains of Aeromonas species of clinical and environmental origin.

The aim of this study was to investigate the presence of markers of pathogenicity islands that may be informative to detect the virulent PAI carriers of clinical and environmental strains of Aeromonas spp. isolated in Mexico. virB2, virB9 and virB11 genes were found in Aeromonas strains isolated from environmental and clinical sources while cagE and tfc16 genes were only in strains of environmental origin. Having performed the wide screening presented in this study, we now have a set of strains to map and confirm the presence of a pathogenicity island in Aeromonas strains isolated in Mexico.

A prospective study on Aeromonas in outpatients with diarrhea in the central region of Rio Grande do Sul State

Aeromonas spp. were identified in five (2,7%) of 182 diarrheal stool cultures, A. caviae was predominant, resistant mainly to ampicillin and cephalotin. This is the first study showing the presence of Aeromonas spp. in diarrheal stools of outpatients in the central region of Rio Grande do Sul State, Brazil.

Evaluation and biochemical characterization of a distinctive pyoverdin from a pseudomonas isolated from chickpea rhizosphere

Microbial siderophores confiscate the available ferric ions around the roots and trigger a reaction resulting in plant growth promotion. In our study, a high level of siderophore production was observed from a newly isolated Pseudomonas sp. from the rhizosphere of Chickpea plants. Under an iron depleted condition in Standard Succinic acid medium a 1000 µgmL-1 of siderophore production was achieved. Increasing the concentration of iron showed an inverse relationship between growth and siderophore production. Fourier Transform Infrared Spectroscopy (FTIR) analysis of the purified crystals, its UV spectral analysis and High Pressure Liquid Chromatography (HPLC) revealed the identity of the siderophore as similar to that of pyoverdin with distinctive characters. Electron spray ionization mass spectroscopy (ESIMS) shows presence of abundance of A1 ions (419 m/z) and branching of amino acids from B1-B5. This pyoverdin contains a cyclic tetra peptide but Serine and Arginine are missing. Based on our analysis and deviations from the reported structure of pyoverdin it is suggested that this pseudomonas produces distinctly characterized pyoverdin siderophore.

Virulence potential and antibiotic susceptibility pattern of motile aeromonads associated with freshwater ornamental fish culture systems: a possible threat to public health

Aeromonas spp. are ubiquitous aquatic organisms, associated with multitude of diseases in several species of animals, including fishes and humans. In the present study, water samples from two ornamental fish culture systems were analyzed for the presence of Aeromonas. Nutrient agar was used for Aeromonas isolation, and colonies (60 No) were identified through biochemical characterization. Seven clusters could be generated based on phenotypic characters, analyzed by the programme NTSYSpc, Version 2.02i, and identified as: Aeromonas caviae (33.3%), A. jandaei (38.3%) and A. veronii biovar sobria (28.3%). The strains isolated produced highly active hydrolytic enzymes, haemolytic activity and slime formation in varying proportions. The isolates were also tested for the enterotoxin genes (act, alt and ast), haemolytic toxins (hlyA and aerA), involved in type 3 secretion system (TTSS: ascV, aexT, aopP, aopO, ascF-ascG, and aopH), and glycerophospholipid-cholesterol acyltransferase (gcat). All isolates were found to be associated with at least one virulent gene. Moreover, they were resistant to frequently used antibiotics for human infections. The study demonstrates the pathogenic potential of Aeromonas, associated with ornamental fish culture systems suggesting the emerging threat to public health.

Characterization of pathogenic Aeromonas veronii bv. veronii associated with ulcerative syndrome from Chinese longsnout catfish (Leiocassis longirostris Günther)

273 bacterial strains were isolated from 20 Chinese longsnout catfish samples. The biochemical characteristics of all strains conformed to the species description of Aeromonas veronii bv. veronii on the basis of Vitek GNI+ card. Furthermore, 16S rDNA, gyrB and rpoD sequences of the representative strain PY50 were sequenced and showed high similarity with A. veronii bv. veronii in Genbank. Antibiotic-resistance of the representative strain PY50 was assessed by the Kirby-Bauer disk diffusion method, and the results showed it was susceptible and moderately susceptible to 13 and 4 of the 21 antimicrobial agents tested. Extracellular products of strain PY50 contained gelatinase, lecithinase, elastase, most of lipase and lipopolysaccharide. Virulence of strain PY50 and extracellular products to Chinese longsnout catfish were also tested, and LD50 were about 3.47~10(4) CFU per fish and 11.22 ƒÊg per fish in intraperitoneal injection respectively. This is the first report that A. veronii bv. veronii was the pathogenic agent of ulcerative syndrome in Chinese longsnout catfish.

Aeromonas spp asociada a enfermedad diarreica aguda en Cuba: estudios de casos y controles / Aeromonas spp asociated to acute diarrheic disease in Cuba: case-control study

The members of the genus Aeromonas are currently considered important gastrointestinal pathogens in different geographical areas. From February 1985 to January 2005 several case-control studies were coordinated by the National Reference Laboratory for Diarrheal Diseases from the Pedro Kouri Institute. The study purpose was to analyze a possible pathogenic role for Aeromonas spp in Cuban children with acute diarrhea. In that period 2,322 children less than 5 years old with acute diarrhea were studied for diarhoeal pathogens and another group of 2,072 non hospitalized children without diarrhea during the similar time from the same geographical areas and matched by ages were recruited. In the group of children with diarrheas (cases), Aeromonas spp. was isolated in 166 (7.15%) and in the control group the microorganism was found in only 35 (1.76%). When Aeromonas isolation rates were compared between both groups, we found that probability to isolate this specie was significantly higher in cases than in controls (OR = 4.48, 95% IC: 3.05-6.60; P < 0.001). The Aeromonas species more frequently isolated were A. caviae, A. hydrophila, and A. veronii bv sobria. Other enteric pathogens detected in children with diarrhea were: Shigella spp in 418 (18%) (P < 0.0001), Salmonella spp in 53 (2.3%) (P < 0.01), and enteropathogenic E. coli in 58 (2.49%) (P < 0.05).

Los miembros del género Aeromonas son considerados patógenos importantes del tracto gastrointestinal en diferentes áreas geográficas. De febrero de 1985 a enero de 2005 se realizaron estudios de casos y controles en el Laboratorio Nacional de Referencia de Enfermedades Diarreicas Agudas del Instituto Pedro Kourí con el objetivo de conocer el comportamiento de los microorganismos pertenecientes al género Aeromonas en niños con diarreas en Cuba. La muestra estuvo constituida por 2.322 niños bajo 5 años de edad, ingresados por enfermedad diarreica aguda y como grupo control se estudió un total de 2.072 niños con edades y áreas geográficas similares que acudieron a los hospitales correspondientes en ese mismo período de tiempo. En el grupo de niños que presentaron diarreas, Aeromonas spp fue aislada en 166 (7,15%), y en los controles fue encontrada en 35 (1,76%). Al comparar la positividad para Aeromonas entre ambos grupos, la probabilidad de diagnosticar este microorganismo fue 4,28 veces mayor en los casos que en los controles (OR = 4,28; IC al 95%: 2,96-6,20; P < 0,001). Las especies más frecuentemente aisladas fueron A. caviae, A. hydrophila, y A. veronii bv sobria. Otros enteropatógenos aislados en niños que presentaban diarrea fueron: Shigella spp. en 418 (18%) (P < 0,0001, Salmonella spp en 53 (2,3%) (P < 0,01),) y E. coli enteropatógena en 58 (2,49%) (P < 0,05).

An in-house multiplex pcr method to detect of putative virulence factors in Aeromonas species

A pentaplex PCR was developed and optimised to detect the genes that encode the five most important putative virulence factors in Aeromonas isolates. It seems to be more efficient than previously reported techniques and promises to be a powerful tool for more accurate risk assessments and for monitoring pathogenic strains.

Caracterización fenotípica de cepas de Aeromonas aisladas de pacientes con enfermedad diarreica aguda / Phenotypic characterization of Aeromonas isolated from patients with acute diarrheal diseases

INTRODUCCIÓN: las enfermedades diarreicas agudas constituyen una de las principales causas de morbilidad y mortalidad en los niños menores de 5 años y en la población general, esto ocasiona una gran demanda de atención en los servicios de salud. La situación se agrava por el abuso de los antimicrobianos y el desarrollo de resistencia bacteriana, suceso que hoy día constituye un problema emergente de salud en diversas regiones del mundo. Entre los microorganismos causantes de enfermedades diarreicas agudas se encuentran los pertenecientes al género Aeromonas, los cuales han sido reconocidos como patógenos emergentes de riesgo II. OBJETIVOS: determinar las especies de Aeromonas más frecuentemente aisladas a partir de muestras de heces de pacientes con enfermedades diarreicas agudas y su susceptibilidad antimicrobiana. MÉTODOS: se determinó la susceptibilidad mediante el método de Bauer-Kirby frente a diferentes antimicrobianos a 100 aislamientos remitidos desde los centros provinciales de higiene y epidemiología del país durante 2007-2008. RESULTADOS: En 67 por ciento de los aislamientos se logró la identificación hasta especie, se observó el predominio de A. caviae (33 por ciento) y A. hydrophila (29 por ciento). Se demostró que 100 por ciento de los aislamientos resultaron resistentes al menos a un antimicrobiano de los investigados. El porcentaje más elevado de resistencia se observó frente a la cefalotina, las sulfonamidas y el ácido nalidíxico. CONCLUSIONES: se propone a la tetraciclina y el cloranfenicol como fármacos de elección para el tratamiento de las infecciones intestinales producidas por estos microorganismos en Cuba.

INTRODUCTION: the acute diarrheal diseases are one of the main causes of morbidity and mortality in children aged under 5 years and in the general population; this demands a great deal of care in the healthcare services. The situation worsens due to the overuse of antimicrobials and the development of bacterial resistance, being the latter an emerging health problem in different areas of the world. Among the causative microorganisms of acute diarrheal diseases are those of Aeromonas genus, recognized as second risk emerging pathogens. OBJECTIVES: to determine the most frequently isolated Aeromonas species in fecal samples from acute diarrheal patients and their antimicrobial susceptibility. METHODS: the Bauer-Kirby´s method allowed identifying the susceptibility to several antimicrobials of 100 isolated samples coming from the provincial hygiene and epidemiology centers during 2007 and 2008. RESULTS: identification of the species was accomplished in 67 percent of isolates, being A. caviae (33 percent) y A. hydrophila (29 percent) the predominant species. It was demonstrated that 100 percent of isolates got resistant to at least one of the studied antimicrobials. Drug resistance to cefalotine, sulfonamides and nalidixic acid showed the highest percentages. CONCLUSIONS: tetracycline and chloramphenicol are recommended as the drugs of choice for treating intestinal infections caused by these microorganisms in Cuba.

The occurrence of Aeromonas in drinking water, tap water and the Porsuk River

The occurrence of Aeromonas spp. in the Porsuk River, public drinking water and tap water in the City of Eskisehir (Turkey) was monitored. Fresh water samples were collected from several sampling sites during a period of one year. Total 102 typical colonies of Aeromonas spp. were submitted to biochemical tests for species differentiation and of 60 isolates were confirmed by biochemical tests. Further identifications of isolates were carried out first with the VITEK system (BioMeÿrieux) and then selected isolates from different phenotypes (VITEK types) were identified using the DuPont Qualicon RiboPrinter® system. Aeromonas spp. was detected only in the samples from the Porsuk River. According to the results obtained with the VITEK system, our isolates were 13 percent Aeromonas hydrophila, 37 percent Aeromonas caviae, 35 percent Pseudomonas putida, and 15 percent Pseudomonas acidovorans. In addition Pseudomonas sp., Pseudomonas maltophila, Aeromonas salmonicida, Aeromonas hydrophila, and Aeromonas media species were determined using the RiboPrinter® system. The samples taken from the Porsuk River were found to contain very diverse Aeromonas populations that can pose a risk for the residents of the city. On the other hand, drinking water and tap water of the City are free from Aeromonas pathogens and seem to be reliable water sources for the community.

Avaliação do sistema de cultivo integrado, a partir da reciclagem de águas residuais submetidas a tratamento primário: pesquisa de espécies dos gêneros Salmonella, Shigella, Vibrio e Aeromonas / Assessment of integrated aquaculture system from the recycling of wastewater undergoing primary treatment: search of species of Salmonella, Schigella, Vibrio and Aeromonas

Para avaliar um sistema integrado de agrucultura foram realizadas análises microbiológicas da água utilizada neste sistema e determinada a incidência e resistência antimicrobiana dos enteropatógenos no ecossistema relacionado. As amostras de água testadas apresentaram 32,9% de taxas de coliformes fecais (<- 1.600/100mL), de acordo com a OMS para piscicultura em águas residuais. Salmonella spp. foram detectadas em 14,5% das amostras. De um total de 33 cepas, 15,1% eram resistentes a um ou dois antimicrobianos testados e resistência a múltiplas drogas não foi observada. Aeromonas spp. foram identificadas em 91,6% das amostras. De um total de 416 cepas, resistência a uma classe de antimicrobianos foi observada em 66,3% e a multirresistência às drogas em 37,7%. Na avaliação da virulência dos isolados de Aeromonas hydrophila, 85,3% das cepas apresentaram Beta-hemólise nos três diferentes tipos de eritrócitos empregados e 99,1% nos eritrócitos de coelho e cavalo, sendo possível a caracterização através da PCR do gene aerA e lip, em 100% das amostras. Os resultados obtidos apontam para a relevância quanto às vantagens da implementação de um sistema integrado, disponibilizando alimentos com custo reduzido, porém este sistema necessita de um controle rígido e efetivo para que estes produtos não constituam veículos para a disseminação de doenças.

To evaluate an integrated aquaculture system, microbiological analyses of water used in this system were carried out and the incidence and antimicrobial resistance of enteropathogens were determined in the related ecosystem. Water samples tested had 32.9% of fecal coliforms rates (<-1600/100mL) in accordance with WHO for psiculture in wastewater. Salmonella spp. were detected in 14.5% of the samples. From a total of 33 strains, 15.1% were resistant to one or two antimicrobial drugs tested and multidrug-resistance was not observed. Aeromonas spp. were identified in 91.6% of the samples. From a total of 416 strains, resistance to one antimicrobial class was observed in 66.3% and multidrug-resistance in 37.7%. In relation to virulence factors of Aeromonas hydrophila, 85.3% of the strains showed beta-hemolysis in three different types of erythrocytes and 99.1% in horse and rabbit erythrocytes. It was possible to characterize by PCR assay, the genes aerA and lip in 100% of the strains. The results indicate the relevance of the benefits of implementing an integrated system, providing food with reduced cost, but this system requires a strict and effective control so that these products do not constitute a vehicle for the spread of disease.

Aeromonas presence in drinking water from collective reservoirs and wells in peri-urban area in Brazil

Aeromonas genus is considered an emerging pathogen and its presence in drinking water supplies is a reason to public health concern. This study investigated the occurrence of Aeromonas in samples from collective reservoirs and wells used as drinking water sources in a peri-urban area. A total of 35 water samples were collected from collective reservoirs and 32 from wells bimonthly, from September 2007 to September 2008. Aeromonas spp determination was carried out using a Multiple-Tube Technique. Samples were inoculated into alkaline peptone water and the superficial film formed was transferred to blood agar plates amended with ampicillin. Typical Aeromonas colonies were submitted to a biochemical screening and then to biochemical tests for species differentiation. Aeromonas was detected in 13 (19 percent) of the 69 samples examined (6 from collective reservoirs and 7 from wells). Concentrations of Aeromonas in collective reservoirs ranged from <0.3 to 1.2 x10²MPN/100mL and, in wells, from <0.3 to 2.4 x10²MPN/100mL. The most frequent specie in the collective reservoir samples was Aeromonas spp (68 percent), followed by A. encheleia (14 percent) and A. allosaccharophila (8 percent) and A. hydrophila (8 percent). Aeromonas spp (87 percent) was the most frequent specie isolated from well samples, followed by A. allosacchariphila (8 percent), A. encheleia (2 percent) and A. jandaei (5 percent). These data show the presence and diversity of Aeromonas genus in the samples analyzed and highlight that its presence in drinking water poses a significant public health concern.

Presence of blaTEM-116 gene in environmental isolates of Aeromonas hydrophila and Aeromonas jandaei from Brazil

It is known that Aeromonas spp. possess different chromosomal â-lactamase genes. Presence and phenotypic expression of blaTEM, blaSHV, and blaCTX-M ESBL-encoding genes were investigated in environmental water isolates of Aeromonas hydrophila and Aeromonas jandaei. Presence of blaSHV and blaCTX-M genes was not observed, and blaTEM gene was verified in 91 percent of the isolates. Sequencing of 10 fragments showed the occurrence of blaTEM-116.

Characterization of aeromonas species isolated from an estuarine environment

Thirty water samples were collected, at two week intervals, from the estuary of the River Cocó. The aim was to characterize the presence, distribution and types of Aeromonas spp, in the estuary of the River Cocó, Ceara, Brazil (03º46'28.83''S e 38º26'36.52''S). Aeromonas were identified in 19 (63 percent) samples analyzed by plating and CFU counts. Presence/absence tests were positive for 11 (37 percent) of the samples resulting in the detection of Aeromonas in a total of 23 (77 percent) of samples. CFU counts varied from < 10 to 1.4 x 10(4) CFU mL-1 . From the isolated strains seven species of Aeromonas were identified: A. caviae (29/69), A. veronii bv. sobria (13/69), A. veronii bv. veronii (8/69), A. trota (6/69), A. media (5/69), A. sobria (4/69) and A. hydrophila and Aeromonas sp. (2/69). Of the 38 strains tested, 23 (60 percent) showed resistance to at least one of the eight antimicrobials. Multiple resistance to antibiotics was observed in A. caviae, A. media, A. sóbria and A. veronii bv. sobria. Aeromonas caviae showed the highest multiple resistance, being resistant to four antibiotics. The presence of those microorganisms may contribute to the occurrence of gastroenteritis, mainly in children, since they are considered opportunists.

Ocorrência de Aeromonas spp. em abatedouro bovino e sensibilidade a antimicrobianos / Occurrence of Aeromonas spp. in bovine abattoir and antimicrobial sensitivity

O gênero Aeromonas compreende espécies consideradas importantes patógenos para os seres humanos, sendo as gastroenterites as infecções mais comumente atribuídas a estas bactérias. Tendo em vista sua importância como patógeno de origem alimentar, a ocorrência deAeromonas spp. foi estudada em carcaças bovinas e ambiente do abatedouro em uma indústria do Estado de São Paulo. Foram colhidas 285 amostras de 19 locais. Foi realizada a contagem direta por semeadura em meio seletivo, caracterização bioquímica das espécies após enriquecimento seletivo e teste de sensibilidade a antimicrobianos. A contagem direta permitiu a quantificação dessas bactérias em apenas 12 amostras, variando de 0,5 a 9,2 x 100 UFC/cm2, sendo cinco delas de ambiente, com populações que variaram de 1,0 x 100 a 3,0 x 100 UFC/placa. Entretanto, após o enriquecimento seletivo, Aeromonas spp. foram isoladas de 38 amostras que, somadas às amostras de ambiente não submetidas ao enriquecimento, forneceram 62 isolados para análise. A caracterização bioquímica das espécies permitiu verificar a ocorrência de 59 isolados de A. caviae, um de A. sobria, um de A. trota e um de A. schubertii. O teste com antimicrobianos revelou resistência de todos os isolados pela ampicilina e cefalotina, enquanto, para os demais antimicrobianos, esta foi variável. A resistência da totalidade dos isolados a determinados antimicrobianos indica que estes devem ser utilizados criteriosamente com a finalidade de evitar o surgimento precoce de cepas deAeromonas spp. multirresistentes. Ainda, a maior prevalência deA. caviae deve ser considerada relevante, pois trata-se de uma das espécies causadoras de gastroenterite em humanos.

The genus Aeromonas comprises important human pathogens, gastroenteritis being the most common type of infection attributed to these bacteria. Considering their importance as foodborne pathogens, the occurrence of Aeromonas spp. was studied on bovine carcasses and the environment of a slaughterhouse in São Paulo State, Brazil. A total of 285 samples were collected from 19 points. Direct counting was carried out by seeding on selective medium, with biochemical characterization of the species after selective enrichment and antimicrobial sensitivity testing. The direct count permitted bacteria quantification only in 12 samples ranging from 0.5 to 9.2 x 100 CFU/ cm2, of which 5 were from environment, ranging from 1.0 x 100 to 3.0 x 100 CFU/plate. However, after selective enrichment,Aeromonas spp. was isolated from 38 samples, which when added to the environmental samples not subjected to the enrichment provided 62 isolates for analysis. Biochemical characterization allowed for the verification of the occurrence of 59 isolates of A. caviae, 1 ofA. sobria, 1 ofA. trota and 1 ofA. schubertii. Antimicrobial testing revealed that all isolates were resistant to ampicillin and cephalotin, while the results for the other antimicrobials were variable. Resistance of all isolates to some antimicrobials indicates that these must be used carefully to avoid early development of multiresistantAeromonas spp. Also, the greatest prevalence of A. caviae must be considered relevant because it is one of the causative species of human gastroenteritis.

Análise do perfil de resistência a antibióticos e detecção dos genes de virulência e resistência em Aeromonas provenientes de amostras ambientais / Analysis of antibiotic resistance profile and detection of virulence and resistance genes in Aeromonas from environmental samples

As Aeromonas são bactérias distribuídas predominantemente em meio aquático. São consideradas patógeno emergente, podendo causar doenças em peixes como também no homem. Os problemas mais comuns são a gastrenterite no homem e morte em peixes. OBJETIVO: Este estudo foi desenvolvido para comparar a identificação fenotípica com a genotípica, e também para conhecer o perfil de resistência aos antibióticos em Aeromonas caviae, A. aquariorum, e A. sanarellii isoladas do ambiente aquático e a presença de genes de virulência e resistência. MATERIAL E MÉTODOS: O DNA das 24 cepas em estudo foi extraído por choque térmico e purificado utilizando CTAB. Foram realizadas as PCRs para a detecção dos genes de virulência e dos genes de resistência, após a realização do antibiograma. RESULTADOS: Foram identificadas 4 A. caviae das quais 3(75,0 por cento) apresentaram pelo menos um dos genes act, ast ou alt. Das 3 A. aquariorum, 1(33,3 por cento) apresentaram positividade para os genes act e ast. Entre os 5 isolados de A. sanarellii 1(50,0 por cento) possuíam os genes alt e ast. Seis isolados não foram posicionados taxonomicamente entre as espécies descritas de Aeromonas, e dentre essas um exemplar apresentou o gene alt. Em relação às enzimas MBL e AmpC foram obtidos respectivamente: 3(100 por cento) e 3(100 por cento) em A. aquariorum; 2(50,0 por cento) e 4(100 por cento) em A. caviae; 3(75,0 por cento) e 5(100 por cento) em Aeromonas spp.; 1(20 por cento) e 5(100 por cento) A. sanarellii; Nenhum isolado apresentou resultado positivo, no teste fenotípico, para a produção de ESBL. Com a realização da PCR foi detectada a presença de 5 amostras com gene tipo blaMOX, 21blaCPHA , 17 tipo blaTEM e 2 cepH. CONCLUSÃO: Os resultados sugerem que os isolados podem servir potencialmente como reservatórios de resistência aos antimicrobianos e ainda, que os isolados podem ser considerados patógeno emergentes e significativos para a saúde pública.

Aeromonas spp. is predominantly distributed in the aquatic environment. They are regarded as emerging pathogen, causing disease in fish but also in man. The most common problems are gastroenteritis in humans and death in fish. OBJECTIVE: This study was designed to compare phenotypic with genotypic identification, and also to know the profile of antibiotic resistance in Aeromonas caviae, A. aquariorum, and A. sanarellii isolated from aquatic environment and the presence of virulence genes and resistance. MATERIAL AND METHODS: DNA from 24 strains under study was extracted by thermal shock and purified using CTAB. PCR reactions were performed for the detection of virulence and resistance genes, after the completion of the antibiotic resistance test. RESULTS: We identified four A. caviae from which 3(75.0per cent) had at least one of the genes act, ast or alt. From 3 A. aquariorum, 1(33.3per cent) was positive for the genes act and ast. Among the five isolated A. sanarellii, 1(50.0per cent) had the alt and ast genes Six isolates were not positioned within taxonomically described species of Aeromonas, and among these only one strain presented the alt gene. Regarding the MBL and AmpC it was obtained respectively: 3(100per cent) and 3(100per cent) isolates from A. aquariorum; 2(50.0per cent) and 4(100per cent) isolates from A. caviae; 4(66.7per cent) and 3(50.0per cent) isolates from Aeromonas spp.; and 1(20per cent) and 5 (100per cent) isolates from A. sanarellii. None of the isolates showed positive results in the phenotypic test for ESBL production. The PCR reaction detected the presence of 5 strains with blaMOX-like gene; 21 with blaCPHA gene; 17 with blaTEM-like gene and 2 with cepH gene. CONCLUSION: These findings suggest that the isolates may serve as potential reservoirs of antimicrobial resistance and also that the isolates could be considered emerging pathogens of public health significance.

Effect of sprulina platensis on the immune response of cultured oreochromis niloticus

The use of microalgae in the field of fish feeding is still operated in a small scale. This study was conducted to evaluate the effects of using the microalga Spirulina platensis powder as a feed additive in fish diets. So, we use a total number of 120 apparently healthy Oreochromis niloticus, with average body weight of fish [50 +/- 5g] were obtained from Barseek fish farm at Behera Governorate. The present work was designed to investigate the different immunostimulant effects of Spirulina on some cultured freshwater fish including serum proteins, [Lymphocytes and monocytes] as well as phagocytic activity, index and the level of antibody titer, relative level of protection. For these investigations four experimental diets were carried out by addition of Spirulina platensis powder to balanced fish diet. 1[st] group: fed on 1[st] diet which is formed of fish diet with addition of 2.5% Spirulina platensis powder to it. 2[nd] group: fed on 2[nd] diet which is formed of fish diet with addition of 5% Spirulina platensis powder to it. 3[rd] group: fed on 3[rd] diet which is formed of fish diet with addition of 10% Spirulina platensis powder to it. 4[th] group: fed on 4[th] diet which is formed of fish diet without addition of Spirulina platensis powder to it [Control group]. The most important results of this study include: 1.There was a tendency for the WBCs values had the highest values during addition of Spirulina also there was increasing in lymphocyte and monocytes in groups fed on Spirulina than the control groups. 2. Fish groups supplemented with Spirulina showed increased of phagocytic activity and phagocytic index until the 4[th] weeks from feeding Spirulina. 3. In the present work, the significant increase in albumin, globulin and total protein and increase of albumin/globulin [A/G] ratio in the groups fed on Spirulina than control group 4. The antibody titers in all Spirulina supplemented groups were highor than the control feed on basal diet where ranged between 2 +/- 0.1, 3 +/- 0.1, 4 +/- 0.3 and 4 +/- 0.3 during 1[st], 2[nd], 3[rd] and 4[th] weeks respectively and at the end of the 4[th] week, the antibody titers ranked in groups where the 10% Spirulina supplemented group come in the first rank, followed by 5% Spirulina supplemented group, then 2.5% Spirulina supplemented group while the control group came in the last rank in values. 5. The potency of bacterin was examined by calculating the relative level of protection [RLP]. In this study, we examined the disease resistance in Spirulina - treated tilapia using the tilapia pathogen Aeromonas hydrophila