Comparative Study on the Predominance of Lactobacillus spp. and Escherichia Coli in Healthy vs Colibacillosis Diseased Broilers

This study aims to identify relative proportions of beneficial and pathogenic bacteria in the gut of broilers and risk factors that may be contributing to the development of colibacillosis disease in broiler farms of District Kasur, Punjab, Pakistan. For this, 10 healthy and 10 colibacillosis affected broiler farms were surveyed for ileum and blood sample collection along with data regarding farm management, antibiotic use and hygiene practices. Lactobacillus and Escherichia coli number was estimated using Miles and Misra method and colibacillosis was confirmed by Congo red dye assay. Lactobacillus and E. coli were identified biochemically. For risk factors analysis chi-square analysis was performed to find any significant association between the health status of the farm and risk factors. Results showed during disease and healthy conditions Lactobacillus and Escherichia coli counts differ significantly (p<0.05). E. coli counts (106-108 to 107-109) increased (p<0.05) about three folds and Lactobacillus counts decrease (106-108 to 105-107) about four folds in disease conditions. Risk factor analysis showed colibacillosis disease was significantly associated (p<0.05) with non-vaccinated flocks, natural ventilation systems, rodent presence and the lack of outfit disinfection or change by workers when moving between different houses. It is concluded that E. coli and Lactobacillus work antagonistically to each other. However, further research is necessary to determine the exact mechanisms by which E. coli and Lactobacillus influence the development of colibacillosis. While Lactobacillus as probiotic may help with prevention, good hygiene and management practices are still crucial in preventing the spread of disease.(AU)

Identification and characterization of pathogenic and multidrug-resistant bacteria in feral pigeons surrounding a veterinary hospital in Minas Gerais, Brazil / Identificação de bactérias patogênicas e multirresistentes a antimicrobianos em pombos urbanos no entorno de um Hospital Veterinário em Belo Horizonte, Minas Gerais, Brasil

Pigeons are known for their capacity to harbor and spread several zoonotic agents. Studies have suggested that pigeons are also relevant disseminators of multidrug-resistant strains. In this study, pigeons surrounding a veterinary hospital were sampled and tested for the presence of pathogenic Escherichia coli, Salmonella spp., Staphylococcus spp., and Clostridioides (Clostridium) difficile. E. coli isolates from 19 (40.4%) pigeons tested positive for the E. coli heat-stable enterotoxin 1 (EAST1)-encoding gene. The intimin-encoding gene (eae) of enteropathogenicE. coli (EPEC) was found in one isolate (2.1%). Salmonella spp. were found in nine (19.1%) pigeons, all from the first capture event (P < 000.1). S. Typhimurium and S. Heidelberg were isolated from six and three pigeons, respectively. Enterobacterial repetitive intergenic consensus (ERIC-PCR) of the Salmonella spp. isolates suggested that eight of the nine strains had a high genetic similarity, supporting the hypothesis of an outbreak of salmonellosis in these pigeons. Twenty (42.5%) staphylococcal isolates were recovered from 18 (38.3%) pigeons. Eight different species were detected, with S. xylosus being the most frequent. Two (4.3%) C. difficile strains were isolated. Three isolates, one each of S. Typhimurium, S. aureus, and C. difficile, were classified as multidrug-resistant strains. The present research suggested that pigeons residing in urban areas can act as reservoirs and disseminators of pathogenic bacteria, including nosocomial pathogens, such as diarrheagenicE. coli and multidrug-resistant Staphylococcus spp., C. difficile, and Salmonella spp.

Pombos urbanos são conhecidos pela sua capacidade de carrear e disseminar diversos agentes zoonóticos. Estudos tem sugerido que pombos são também relevantes na disseminação de estirpes resistentes a múltiplas drogas. No presente estudo, pombos no ambiente de um hospital veterinário foram amostrados em três diferentes períodos e testados para a presença de Escherichia coli patogênica, Salmonella spp., Staphylococcus spp. e Clostridioides (Clostridium) difficile. Isolados de E. coli de 19 pombos (40.4%) foram positivos para o gene codificador da toxina EAST1. O gene codificador de intimina (eae) do patotipo E. coli enteropatogênica foi encontrada em um isolado (2.1%). Salmonella spp. foi encontrada em nove pombos (19.1%), sendo todos isolados do primeiro período de captura (P < 000.1). S. Typhimurium foi isolado de seis animais e S. Heidelberg de três. A tipagem molecular de isolados de Salmonella spp. por ERIC-PCR demonstrou que oito estirpes possuíam alta similaridade genética entre si, sugerindo a ocorrência de um surto de salmonelose nos animais carreadores. Vinte Staphylococcus (42.5%) foram isolados de 18 animais (38.3%). Oito diferentes espécies foram detectadas, sendo S. xylosus a mais frequente. Duas estirpes de C. difficile não-toxigênica (4.3%) foram isoladas. Uma estirpe de S. Typhimurium, uma de S. aureus e um isolado de C. difficile foram classificados como resistentes a múltiplas drogas antimicrobianas. O presente estudo sugere que pombos capturados no ambiente do hospital veterinário podem atuar como reservatórios e disseminadores de bactérias patogênicas e envolvidas em infecção hospitalar, incluindo E. coli diarreiogênica e Staphylococcus sp., C. difficile e Salmonella spp multirresistente.

Urethral obstruction due to seminal vesiculitis in a sheep: case report / Obstrução uretral por vesiculite seminal em ovino: relato de caso

We report a case of urethral obstruction due to seminal vesiculitis in a Dorper sheep, with symptoms of anuria, rectal prolapse, orchitis/epididymitis, and uroperitoneum and biochemical tests indicating severe azotemia. The animal died due to advanced azotemia, and necropsy revealed kidneys with cortical and medullary necrosis, pyelonephritis of renal calyces, hydronephrosis, ruptured and necrotic bladder, and vesicular, bulbourethral, and ampoule accessory sex glands. There was prostate hyperplasia that revealed a large amount of pus in the cross section, which was also observed bilaterally in the epididymis and right testis. Morphotintorial and biochemical analyses of bacteria obtained from microbiological culture revealed Corynebacterium sp. and Escherichia coli. Infection, hyperplasia, and abscessation of accessory sex glands caused urethral compression, resulting in an obstructive condition, similar to urolithiasis, in addition to bacteremia. Hyperplastic seminal vesiculitis, although rare, must be included among the differential diagnoses of obstructive processes in the urinary tract of sheep.

Relata-se um caso de obstrução uretral decorrente de vesiculite seminal em carneiro da raça Dorper, com quadro de anúria, prolapso retal, orquite/epididimite e uroperitôneo, com exames bioquímicos indicativos de severa azotemia. Devido ao quadro avançado de azotemia, o animal faleceu e, na necropsia, foi observado:: rins com necrose de cortical e medular, pielonefrite dos cálices renais e hidronefrose, bexiga rompida e necrosada, assim como glândulas sexuais acessórias vesiculares, bulbouretrais e ampola. Havia hiperplasia de próstata que, ao corte transversal, revelou grande quantidade de pus, que também foi observado bilateralmente no epidídimo e no testículo direito. As análises morfotintoriais e bioquímicas das bactérias obtidas a partir do cultivo microbiológico foram compatíveis com Corynebacterium sp. e Escherichia coli. A infecção, a hiperplasia e a abscedação das glândulas sexuais acessória, causaram compressão uretral, levando a um quadro obstrutivo, semelhante à urolitíase, somado à bacteremia. A vesiculite seminal hiperplásica, apesar de rara, deve ser incluída entre os diagnósticos diferenciais dos processos obstrutivos do trato urinário de carneiros.

Detection and Antimicrobial Resistance Profile of Enteropathogenic (EPEC) and Shigatoxigenic Escherichia coli (STEC) in Conventional and Organic Broiler Chickens

Enteropatogenic Escherichia coli (EPEC) and shigatoxigenic E. coli (STEC), are generally poultry and poultry product isolate and can cause serious human infections. Many strains may become resistant to various antimicrobials, which can hinder the treatment of bacterial diseases. Organic farming seeks to avoid the selection and frequency of antimicrobial-resistant bacteria. This study aims to verify the resistance of EPEC and STEC from organic and conventional (industrial) broiler isolates to antimicrobials. All isolates were submitted to disk diffusion test with tetracycline, gentamicin, enrofloxacin, ceftriaxone and amoxicillin + clavulanate (TET, GEN, ENO, CTX, AMC) and PCR to detect specific virulence genes for EPEC and STEC. A total of 297 E. coli strains were isolated, 213 from conventional. In organic broiler, 84 strains were isolated. The strains from the conventional broiler isolates were resistant to five antimicrobials tested: TET 48.82% (104/213), ENO 28.17% (60/213), CTX 15.49% (33/213), GEN 14.55% (31/213), and AMC 7.04% (15/213), and 9.86% (21/213) were considered multidrug-resistant. Organic chicken strains were resistant to four of the antimicrobials tested: TET 35.7% (30/84), ENO 9.5% (8/84), CTX 2.4% (2/84), GEN 4.8% (4/84). Of the strains from the organic broiler chicken isolates, only 1.2% (1/84) was considered multidrug-resistant. No EPEC and STEC were found in the organic chicken samples. The multidrug resistance was characterized in 9.52% (2/21) of the EPEC and 4.76% (1/21) of the STEC. The study demonstrated the absence of EPEC and STEC strains in organic broilers and carcasses and a lower frequency of multiresistant strains compared to conventional breeding.(AU)

Molecular identification of pathogenic Escherichia coli virulence genes and histopathological analysis in chickens condemned for airsacculitis / Identificação molecular de genes de virulência de Escherichia coli e análise histopatológica em frangos condenados por aerossaculite

ABSTRACT: The present study identified virulence genes and pathological changes caused by Escherichia coli in chicken carcasses condemned for airsacculitis and assessed if the histopathological examination and polymerase chain reaction (PCR) were effective for studies like this. Trachea, liver, and lung were collected from 30 chickens with suspected airsacculitis that has been condemned in the inspection line. The samples were analyzed by PCR to simultaneously identify two virulence genes (iss and tsh genes) and for histopathological testing. PCR efficiently genotypically characterize the E. coli isolates, where the virulence genes iss and tsh were found in three birds simultaneously. The histopathological examination detected a predominance of heterophils and mononuclear cells in the trachea (100%), lung (90%), and liver (13.3%). The liver was the organ where practically no alteration was diagnosed. The results of multiplex PCR for the tsh and iss virulence genes indicate the great potential of the approach in the characterization of E. coli isolates. Unspecific identification did not occur, thus making it necessary to use technologies for the identification and prevention of this agent in aviaries and poultry abattoirs.

RESUMO: O objetivo do presente estudo foi identificar genes de virulência e alterações patológicas provocadas por Escherichia coli em carcaças de frango condenadas por aerossaculite e se o exame histopatológico e uma Reação em Cadeia da Polimerase (PCR) são eficazes para os estudos dessa natureza. Para isso, foram coletados traqueia, fígado e pulmão de 30 frangos condenados na linha de inspeção, com suspeita de aerossaculite. As amostras foram submetidas a PCR para a identificação de dois genes de virulência de modo simultâneo (genes iss e tsh) e ao teste histopatológico. A PCR foi eficiente para caracterizar genotipicamente os isolados de E. coli, em que se constatou em três aves os genes de virulência iss e tsh simultaneamente. No exame histopatológico detectou-se a predominância de heterófilos e mononucleares na traqueia 100%, no pulmão 90% e no fígado 13,3%. O fígado foi o órgão onde praticamente não foi diagnosticada nenhuma alteração. Diante dos resultados obtidos, foi possível observar que a PCR multiplex para os genes de virulência tsh e iss apresenta um grande potencial na caracterização de isolados de E. coli, já que não gerou identificação inespecífica, com isso faz-se necessária a utilização de tecnologias para identificação e prevenção desse agente nos aviários e matadouros avícolas.

Identification of Virulence-Associated Markers in Escherichia Coli Isolated from Captive Red-Browed Amazon Parrot (Amazona Rhodocorytha)

Due to the genetic similarity of pathogenic Escherichia coli isolated from birds and pathotypes of human origin, it is suggested that they have a common ancestor and may exchange virulence-associated genes. This study aimed to detect virulence-associated genes in E. coli strains isolated from the Red-browed Amazon parrot (Amazona rhodocorytha) kept at a conservation institute in Brazil. High genetic variability in virulence was observed, since 12 virulence profiles were found among 14 strains. The number of virulence-associated genes of single strains ranged from 5 to 22 out of 33 genes tested, and only one strain did not present any virulence genes. Regarding adhesion genes, most strains presented from two to five genes, and crlA (85.7%) and fimC (85.7%) were the most frequent. Frequencies were similar for invasion and iron acquisition genes. Variations among genes were observed for serum resistance and toxin-related genes. Some of the E. coli strains isolated from parrots presented virulence genes that are commonly associated with pathotypes of human origin, including newborn meningitis E. coli, uropathogenic E. coli, and sepsis-associated E. coli. It is noteworthy that some of these genes were present in the majority of the analyzed strains. Our results indicate that these strains detected in clinically healthy parrots can be potential reservoirs of several virulence-associated genes. These genes can be transmitted to other E. coli strains, including those that affect humans. These E. coli strains present a high pathogenic potential of virulence-associated genes in extraintestinal pathogenic E. coli strains.(AU)

Ultrasound assessment of sheep stifle joint undergone lipopolysaccharide-induced synovitis / Ultrassonografia da articulação femorotibiopatelar em ovinos submetidos à indução de sinovite por lipopolissacarídeos

Synovitis can be induced in animals through the application of bacterial wall lipopolysaccharide and has similar signs to naturally-occurring synovitis. Several studies have been using the sheep species as an experimental model to understand osteoarticular diseases of the femorotibiopatellar (FTP) joint in humans. There are echographic studies on the standardization of normality of the femorotibiopatellar joint in sheep. However, there is a gap in the literature for changes such as acute synovitis. The objective was to serially describe the sonographic aspects of the synovitis process induced by intra-articular infiltration of Escherichia coli (E. coli) lipopolysaccharide in the femorotibiopatellar joint of sheep. Twelve healthy crossbred sheep (Santa Inês x Dorper) were used. Induction of synovitis was performed only in the right FTP joints, which were serially evaluated using ultrasound examination at baseline moment (M0) and 12 (M12), 24 (M24), 48 (M48), 72 (M72), and 120 (M120) hours after lipopolysaccharide infiltration for synovitis induction. Intra-articular application of E. coli lipopolysaccharide resulted in one or more echographic signs of synovitis (increased synovial fluid volume, folding of the synovial membrane, and cellularity in the joint cavity), which were identified early, 12 hours after inoculation, and regressed over the evaluated times (p=0.0001) until disappearing after 120 hours of inoculation.

A sinovite pode ser induzida em animais por meio da aplicação de lipopolissacarídeo de parede bacteriana, e apresenta sinais semelhantes à sinovite causada de forma natural. Diversos estudos têm sido realizados utilizando a espécie ovina como modelo experimental na compreensão das enfermidades osteoarticulares da articulação femorotibiopatelar (FTP) em humanos. Existem estudos ecográficos quanto a padronização da normalidade da articulação femorotibiopatelar em ovinos. Porém, para as alterações, como a sinovite aguda há lacuna na literatura. Objetivou-se descrever, de forma seriada, os aspectos ultrassonográficos do processo de sinovite induzida por infiltração intra-articular de lipopolissacarídeo de Escherichia coli (E. coli) na articulação femorotibiopatelar de ovinos. Foram utilizados 12 ovinos mestiços (Santa Inês x Dorper), hígidos. A indução da sinovite foi realizada apenas nas articulações FTP direitas, as quais foram avaliadas, por meio do exame ultrassonográfico de forma seriada, nos momentos basal (M0) e às 12 (M12), 24 (M24), 48 (M48), 72 (M72) e 120 (M120) horas após a infiltração com lipopolissacarídeo para a indução de sinovite. A aplicação intra-articular de lipopolissacarídeo de E. coli resultou em um ou mais sinais ecográficos de sinovite (aumento de volume do fluido sinovial, pregueamento da membrana sinovial e celularidade na cavidade articular), os quais foram identificados precocemente, 12 horas após a inoculação, e regrediram ao longo dos tempos avaliados (p=0,0001), até desaparecerem após 120 horas da inoculação.

Use of MALDI-TOF for identification and surveillance of gramnegative bacteria in captive wild psittacines / Uso do MALDI-TOF para identificação e monitoramento de bactérias Gram negativas em psitacídeos cativos

Microbiological studies of the sanitary and health status of psittacine birds that will be reintroduced is important in evaluating whether these animals act as carriers of pathogenic agents to other animals and humans. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a faster and more accurate method to identify bacteria than conventional microbiology methods. The aim of this study was to evaluate the health status of psittacines housed in captivity, by assessment of Gram-negative bacteria from fecal microbiota through MALDI- TOF MS identification. The results indicate high frequency of Gram-negative bacteria in feces (96.5%), especially from the Enterobacteriaceae family (88.7%). The most prevalent bacteria were Escherichia coli (39.0%), Proteus vulgaris (12.2%), Klebsiella spp. (12.1%) and Raoultella ornithinolytica (8.7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. and Escherichia hermannii were isolated with lower frequency. . All these agents are potentially pathogenic for parrots and can cause systemic infections in other animals and humans. These findings reinforce that MALDI- TOF MS proved to be a rapid and accurate method of identification of the microorganism and evaluation of the health status of psittacines, providing relevant data to assist decision-making regarding the sanitary protocols in wildlife centers, and possible future reintroduction of wild birds.

Estudos microbiológicos da sanidade de psitacídeos que serão reintroduzidos são importantes para avaliar se esses animais atuam como portadores de agentes patogênicos para outros animais e humanos. A espectrometria de massa por ionização/dessorção de matriz assistida por laser/tempo de vôo (MALDI-TOF MS) é um método mais rápido e preciso para identificar bactérias na comparação com métodos convencionais de microbiologia. O objetivo deste estudo foi avaliar o estado de saúde de psitacídeos cativos, identificando bactérias Gram-negativas da microbiota fecal por MALDI -TOF MS. Os resultados indicaram alta frequência de bactérias Gram-negativas nas fezes (96,5%), principalmente da família Enterobacteriaceae (88,7%). As mais prevalentes foram Escherichia coli (39,0%), Proteus vulgaris (12,2%), Klebsiella spp. (12,1%) e Raoultella ornithinolytica (8,7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. e Escherichia hermannii foram isolados com menor frequência. Todos esses agentes são potencialmente patogênicos para os papagaios e podem causar infecções sistêmicas em outros animais e seres humanos. Esses achados reforçam que o MALDI- TOF MS é um método rápido e preciso de identificação do microrganismo e avaliação do estado de saúde dos psitacídeos, fornecendo dados relevantes para auxiliar na tomada de decisões sobre os protocolos sanitários em centros de triagem de animais selvagens e sobre a possibilidade de reintrodução futura.

Use of MALDI-TOF for identification and surveillance of gramnegative bacteria in captive wild psittacines / Uso do MALDI-TOF para identificação e monitoramento de bactérias Gram negativas em psitacídeos cativos

Microbiological studies of the sanitary and health status of psittacine birds that will be reintroduced is important in evaluating whether these animals act as carriers of pathogenic agents to other animals and humans. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a faster and more accurate method to identify bacteria than conventional microbiology methods. The aim of this study was to evaluate the health status of psittacines housed in captivity, by assessment of Gram-negative bacteria from fecal microbiota through MALDI- TOF MS identification. The results indicate high frequency of Gram-negative bacteria in feces (96.5%), especially from the Enterobacteriaceae family (88.7%). The most prevalent bacteria were Escherichia coli (39.0%), Proteus vulgaris (12.2%), Klebsiella spp. (12.1%) and Raoultella ornithinolytica (8.7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. and Escherichia hermannii were isolated with lower frequency. . All these agents are potentially pathogenic for parrots and can cause systemic infections in other animals and humans. These findings reinforce that MALDI- TOF MS proved to be a rapid and accurate method of identification of the microorganism and evaluation of the health status of psittacines, providing relevant data to assist decision-making regarding the sanitary protocols in wildlife centers, and possible future reintroduction of wild birds.(AU)

Estudos microbiológicos da sanidade de psitacídeos que serão reintroduzidos são importantes para avaliar se esses animais atuam como portadores de agentes patogênicos para outros animais e humanos. A espectrometria de massa por ionização/dessorção de matriz assistida por laser/tempo de vôo (MALDI-TOF MS) é um método mais rápido e preciso para identificar bactérias na comparação com métodos convencionais de microbiologia. O objetivo deste estudo foi avaliar o estado de saúde de psitacídeos cativos, identificando bactérias Gram-negativas da microbiota fecal por MALDI -TOF MS. Os resultados indicaram alta frequência de bactérias Gram-negativas nas fezes (96,5%), principalmente da família Enterobacteriaceae (88,7%). As mais prevalentes foram Escherichia coli (39,0%), Proteus vulgaris (12,2%), Klebsiella spp. (12,1%) e Raoultella ornithinolytica (8,7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. e Escherichia hermannii foram isolados com menor frequência. Todos esses agentes são potencialmente patogênicos para os papagaios e podem causar infecções sistêmicas em outros animais e seres humanos. Esses achados reforçam que o MALDI- TOF MS é um método rápido e preciso de identificação do microrganismo e avaliação do estado de saúde dos psitacídeos, fornecendo dados relevantes para auxiliar na tomada de decisões sobre os protocolos sanitários em centros de triagem de animais selvagens e sobre a possibilidade de reintrodução futura.(AU)

Microbiological water quality monitoring of four ponds from Lagoa do Sino Farm located in São Paulo State, Brazil

This study aimed to evaluate the microbiological quality of the water of four ponds used for irrigation on the Lagoa do Sino Farm, as well as to perform the genotypic characterization of virulence factors in Escherichia coli isolates. Sampling was conducted for 11 months, between 2015 and 2016. Samples were analyzed for the presence of thermotolerant coliforms, E. coli and heterotrophs. DNA was extracted from E. coli isolates, followed by genotypic characterization by polymerase chain reaction. Agricultural activities and pesticides used in the sampling period were documented in order to assess possible relationships between agricultural activities and microbiological water quality. The absence of suitable riparian vegetation around all the ponds was observed, benefiting the entry of organic matter and contaminants in the water body. A high index of thermotolerant coliforms in some months indicated the possibility of the transmission of pathogenic microorganisms in these ponds. The values found in some months were above the regulatory limits for water potability and water intended for irrigation. The agrochemicals used in the period seem to influence the results obtained. All 17 E. coli isolates showed at least one of the virulence genes estA, stx1, stx2, and aatA, indicating enterotoxigenic, enterohaemorrhagic or enteroaggregative nature. The presence of E. coli in the waters may be associated with the presence of animals. The water samples analyzed are not suitable for irrigation of vegetables that are consumed raw and/or low lying fruits ingested without skin removal. It is essential to broaden the control of the use of chemicals, as well as the preservation of riparian vegetation to improve the quality of water used in the farm's agricultural activities.

Microbiological water quality monitoring of four ponds from Lagoa do Sino Farm located in São Paulo State, Brazil

This study aimed to evaluate the microbiological quality of the water of four ponds used for irrigation on the Lagoa do Sino Farm, as well as to perform the genotypic characterization of virulence factors in Escherichia coli isolates. Sampling was conducted for 11 months, between 2015 and 2016. Samples were analyzed for the presence of thermotolerant coliforms, E. coli and heterotrophs. DNA was extracted from E. coli isolates, followed by genotypic characterization by polymerase chain reaction. Agricultural activities and pesticides used in the sampling period were documented in order to assess possible relationships between agricultural activities and microbiological water quality. The absence of suitable riparian vegetation around all the ponds was observed, benefiting the entry of organic matter and contaminants in the water body. A high index of thermotolerant coliforms in some months indicated the possibility of the transmission of pathogenic microorganisms in these ponds. The values found in some months were above the regulatory limits for water potability and water intended for irrigation. The agrochemicals used in the period seem to influence the results obtained. All 17 E. coli isolates showed at least one of the virulence genes estA, stx1, stx2, and aatA, indicating enterotoxigenic, enterohaemorrhagic or enteroaggregative nature. The presence of E. coli in the waters may be associated with the presence of animals. The water samples analyzed are not suitable for irrigation of vegetables that are consumed raw and/or low lying fruits ingested without skin removal. It is essential to broaden the control of the use of chemicals, as well as the preservation of riparian vegetation to improve the quality of water used in the farm's agricultural activities.(AU)

Virulence genes and resistance profile of Escherichia coli isolated in meat meal samples

Feed is the main route of transmission of pathogenic microorganisms and is responsible for a large part of the cost of poultry production, so the inclusion of alternative foods in diets for monogastrics has been a constant. Among alternative foods most used in modern poultry farming are animal meal, however, when contaminated they constitute a route of transmission of several pathogenic agents, including Escherichia coli. In addition, there is a zoonotic potential, as poultry products are intended for human consumption. The objective of this research was to detect virulence genes, as well as to evaluate the resistance profile of Escherichia coli isolates from meat meal samples. A total of 40 Escherichia coli isolates were analyzed and the virulence genes surveyed iss, ompT, hlyF, iutA, and fimA identified by Polymerase Chain Reaction (PCR). The antimicrobial agents tested were: amoxycillin (30 µg), ceftiofur (30 µg), ciprofloxacin (5 µg), doxycycline (30 µg), florfenicol (30 µg), fosfomycin (200 µg), gentamicin (10 µg), norfloxacin (10 µg) and oxacillin (1 µg). It was possible to observe the occurrence of the iss resistance gene in 100% of Escherichia coli isolates, followed by hlyF (85%), fimA (75%), ompT (17.5%) and iutA (5%). Regarding the simultaneous detection for the genes, a greater association between the genes iss, hlyF and fimA (60%) was verified. All isolates showed resistance to oxacillin (100%), followed by doxycycline (25%), amoxicillin (22.5%), norfloxacin (17.5%), ceftiofur (15%), florfenicol (12.5%), fosfomycin (12.5%), ciprofloxacin (10%) and gentamycin (2.5%). In this study, a variation of the multiple antimicrobial resistance index (IRMA) was observed between 0.22 and 0.77. The indiscriminate use of of antimicrobials as performance enhancers in production animals, may have contributed to the increase in antimicrobial resistance, with the occurrence of multiresistant Escherichia coli carrying virulence genes. Virulence genes present in Escherichia coli isolates are studied to understand the degree of influence they exert in the establishment of the disease, one of the most researched genes is the iss gene, involved in the processes that promote serum resistance. In this study, iss (100%) was present in all the isolates analyzed, although it is not the only mechanism used by these bacteria to reach internal organs and trigger an infection, this gene encodes an important mechanism associated with high levels of virulence. The second highest prevalence found was of the hlyF gene (85%), the high prevalence of hlyF suggests virulence potential, involved with the production of hemolysin and improvement of outer membrane vesicles associated with the release of toxins. The fimA gene (75%) was detected in a slightly lower percentage when compared to iss and hlyF. With the second lowest prevalence, the ompT gene (17.5%), is involved in a process that includes the proteolytic degradation of antimicrobial peptides and with the lowest prevalence the iutA gene (5%). Certain combinations of virulence genes make the strains easier to survive, adhere to, colonize and even the ability to develop septicemic conditions. Multiresistant E. coli strains, is a fact of concern for both animal and human health, since the presence of multiresistant strains, originating from poultry, can be transmitted from chicken carcasses. In this sense, the importance of sanitary control of the inputs used in animal feed is emphasized, as well as the prudent use of antimicrobials in animal production, with a view to producing a safe food, minimizing not only the economic losses, but also the risks to human health.(AU)

Co-relationship between Escherichia coli in broiler cellulitis and liver lesions / Correlação entre a presença de Escherichia coli em lesões de celulite e fígados de frango

Pathogenic strains of Escherichia coli may invade the subcutaneous tissue of poultry and cause cellulitis, whilst the pathogen may also cause lesions in internal organs such as the liver. Current paper co-relates Escherichia coli and virulence genes characteristic of Avian Pathogenic Escherichia coli (APEC) in broilers´ cellulitis and liver lesions. One hundred carcasses were retrieved from the production chain in an avian abattoir in the state of Bahia, Brazil, between August 2013 and January 2014, due to detection of cellulitis lesions. Cellulitis and liver samples were retrieved aseptically to quantify E. coli by Petrifilm count fast method (3M Company) (AOAC 998.8). Virulent genes iss and iutA were removed from E. coli isolates by Polymerase Chain Reaction (PCR). Escherichia coli was isolated from 82.0% of broilers removed from the production chain and the bacterium was concomitantly detected in cellulitis and liver lesions in 40.0% of broilers. E. coli counts ranged between 1.00 and 4.73 log CFU/g in liver lesions and between 2.00 and 9.00 log UFC/g in cellulitis lesions. Virulent genes iutA and iss were detected in 97.56% and 89.02% of E. coli isolates, respectively. Genotype analysis demonstrated the concomitant amplification of genes iutA and iss in 60.0% (n=40) of samples of cellulitis and liver lesions in which the simultaneous isolation of E. coli occurred. There was a positive and significant co-relationship (r=0.22; p 0.05) between the variables occurrence of E. coli isolated from liver samples and the occurrence of E. coli isolated from cellulitis lesions. There were also positive and significant co-relationships between populations of E. coli from liver isolates and cellulitis lesions (r=0.46; p 0.05) when E. coli isolated in the liver and in cellulitis lesions was detected. Since results showed a relationship between E. coli in cellulitis and liver lesions and possible systemic infection, the occurrence of cellulitis lesions as a criterion for total discarding of carcass may be suggested.(AU)

Cepas patogênicas de Escherichia coli podem invadir o tecido subcutâneo das aves e provocar celulite aviária e este patógeno pode provocar lesões nos órgãos internos, como o fígado. Desta forma, objetivou-se correlacionar a presença de Escherichia coli e os genes de virulência característicos de Escherichia coli Patogênica para Aves (APEC) nas lesões de celulite e nos fígados dos frangos. Entre agosto de 2013 a janeiro de 2014, foram retiradas 100 carcaças da linha de produção por apresentarem lesões de celulite em um matadouro avícola da Bahia (Brasil). Foram coletadas amostras de celulite e fígados de frango assepticamente para quantificação de E. coli pelo método rápido de contagem Petrifilm (3M Company) (AOAC 998.8). Em seguida foi realizada a pesquisa dos genes de virulência iss e iutA nos isolados de E. coli utilizando a Reação em Cadeia da Polimerase (PCR). Escherichia coli foi isolada em 82,00% das aves retiradas da linha de produção e a bactéria foi detectada concomitantemente nas lesões de celulite e fígado em 40,00% das aves. As contagens de E. coli variaram de 1,00 a 4,73 log UFC/g nos fígados e de 2,00 a 9,00 log UFC/g nas lesões de celulite. Os genes de virulência iutA e iss foram encontrados em 97,56% e 89,02% dos isolados de E. coli, respectivamente. A análise genotípica revelou a amplificação concomitante dos genes iutA e iss em 60,00% (n=40) das amostras de lesões de celulite e fígado nas quais houve o isolamento simultâneo de E. coli. Foi observada correlação positiva e significativa (r=0,22; p 0,05) entre as variáveis ocorrência de E. coli isolada das amostras dos fígados e ocorrência E. coli isolada das lesões de celulite e, nos casos em que foi detectada a ocorrência de E. coli isolada em fígado e lesões de celulite, correlações positivas e significativas também foram evidenciadas entre as populações de E. coli dos isolados dos fígados e das lesões de celulite, (r=0,46; p 0,05). Assim ficou evidenciada a relação entre E. coli presente nas lesões de celulite e no fígado e uma possível infecção sistêmica, desta forma, sugere-se que a presença de lesões de celulite seja utilizada como critério para o descarte total da carcaça.(AU)

Subinhibitory concentrations of silver nanoparticles and silver nitrate on the adaptative and cross-resistance to antibiotics on bovine mastitis pathogens / Concentrações subinibitórias de nanopartículas de prata e nitrato de prata na resistência adaptativa e cruzada com antibióticos em patógenos de mastite bovina

Biocides and/or antibiotics used in subinhibitory concentrations can promote the development of adaptive resistance or even cross-resistance in microorganisms. However, studies on these responses following silver treatments are scarce in the literature. Silver-based compounds, including silver nanoparticles (Ag-NPs), can be an alternative in the prevention and treatment of bovine mastitis. Thus, this research evaluated the effect of subinhibitory dosages of Ag-NPs and Ag+ ions from silver nitrate (AgNO3) on Staphylococcus aureus and Escherichia coli isolated from milk of cows with mastitis. Ag-NPs were synthesized by chemical reduction using AgNO3 and sodium citrate and the minimum inhibitory concentration (MIC) of Ag-NPs and Ag+ ions on the mastitis pathogens were determined. Isolates were exposed to subinhibitory concentrations of Ag-NPs or AgNO3 for 10 consecutive days to verify the development of adaptive resistance evaluated by changes in the MIC values. The development of cross-resistance with antibiotics was also studied, being verified by comparing the sensitivity profile of treated cells with non-treated cells. AgNO3 was more effective against all isolates. There was no change in the MIC values or in the antibiotic sensitivity profile for both bacteria following consecutive exposure to subinhibitory dosages of Ag-NPs or AgNO3, indicating that silver was not able to select adaptive resistance or cross resistance to the tested antibiotics. The potential of silver presented by these results is favorable to the continuity of studies aiming to elaborate silver-based therapies for the treatment of bovine mastitis.

Biocidas e/ou antibióticos em concentrações sub-inibitórias podem promover o desenvolvimento de resistência adaptativa ou mesmo resistência cruzada nos micro-organismos. Entretanto, estudos destas respostas após o tratamento com a prata são escassos na literatura. Compostos a base de prata, incluindo as nanopartículas de prata (Ag-NPs), podem ser uma alternativa na prevenção e/ou tratamento de mastite bovina. Assim, este trabalho objetivou determinar o efeito de doses sub-inibitórias de Ag-NPs e dos íons Ag+ provenientes do nitrato de prata (AgNO3) sobre isolados de Staphylococcus aureus e de Escherichia coli, provenientes de leite de vacas com mastite. As Ag-NPs foram sintetizadas por redução química utilizando AgNO3 e citrato de sódio e a Concentração Mínima Inibitória (CMI) das Ag-NPs e íons Ag+ nos patógenos da mastite foi determinada. Os isolados foram expostos a concentrações sub-inibitórias de Ag-NPs ou de AgNO3 por 10 dias consecutivos para verificar o desenvolvimento de resistência adaptativa à prata pela mudança no valor da CMI, e de resistência cruzada com antibióticos pela mudança no perfil de sensibilidade em relação ao controle. AgNO3 apresentou-se mais efetivo contra todos os isolados. Não foi verificada alteração no valor da CMI nem do perfil de sensibilidade aos antibióticos, indicando que não houve seleção de resistência adaptativa à prata e de resistência cruzada aos antibióticos pelos micro-organismos estudados. O uso potencial da prata apresentado nos resultados é favorável à continuidade dos estudos objetivando a elaboração de terapias à base de prata para o tratamento da mastite bovina.

Subinhibitory concentrations of silver nanoparticles and silver nitrate on the adaptative and cross-resistance to antibiotics on bovine mastitis pathogens / Concentrações subinibitórias de nanopartículas de prata e nitrato de prata na resistência adaptativa e cruzada com antibióticos em patógenos de mastite bovina

Biocides and/or antibiotics used in subinhibitory concentrations can promote the development of adaptive resistance or even cross-resistance in microorganisms. However, studies on these responses following silver treatments are scarce in the literature. Silver-based compounds, including silver nanoparticles (Ag-NPs), can be an alternative in the prevention and treatment of bovine mastitis. Thus, this research evaluated the effect of subinhibitory dosages of Ag-NPs and Ag+ ions from silver nitrate (AgNO3) on Staphylococcus aureus and Escherichia coli isolated from milk of cows with mastitis. Ag-NPs were synthesized by chemical reduction using AgNO3 and sodium citrate and the minimum inhibitory concentration (MIC) of Ag-NPs and Ag+ ions on the mastitis pathogens were determined. Isolates were exposed to subinhibitory concentrations of Ag-NPs or AgNO3 for 10 consecutive days to verify the development of adaptive resistance evaluated by changes in the MIC values. The development of cross-resistance with antibiotics was also studied, being verified by comparing the sensitivity profile of treated cells with non-treated cells. AgNO3 was more effective against all isolates. There was no change in the MIC values or in the antibiotic sensitivity profile for both bacteria following consecutive exposure to subinhibitory dosages of Ag-NPs or AgNO3, indicating that silver was not able to select adaptive resistance or cross resistance to the tested antibiotics. The potential of silver presented by these results is favorable to the continuity of studies aiming to elaborate silver-based therapies for the treatment of bovine mastitis.(AU)

Biocidas e/ou antibióticos em concentrações sub-inibitórias podem promover o desenvolvimento de resistência adaptativa ou mesmo resistência cruzada nos micro-organismos. Entretanto, estudos destas respostas após o tratamento com a prata são escassos na literatura. Compostos a base de prata, incluindo as nanopartículas de prata (Ag-NPs), podem ser uma alternativa na prevenção e/ou tratamento de mastite bovina. Assim, este trabalho objetivou determinar o efeito de doses sub-inibitórias de Ag-NPs e dos íons Ag+ provenientes do nitrato de prata (AgNO3) sobre isolados de Staphylococcus aureus e de Escherichia coli, provenientes de leite de vacas com mastite. As Ag-NPs foram sintetizadas por redução química utilizando AgNO3 e citrato de sódio e a Concentração Mínima Inibitória (CMI) das Ag-NPs e íons Ag+ nos patógenos da mastite foi determinada. Os isolados foram expostos a concentrações sub-inibitórias de Ag-NPs ou de AgNO3 por 10 dias consecutivos para verificar o desenvolvimento de resistência adaptativa à prata pela mudança no valor da CMI, e de resistência cruzada com antibióticos pela mudança no perfil de sensibilidade em relação ao controle. AgNO3 apresentou-se mais efetivo contra todos os isolados. Não foi verificada alteração no valor da CMI nem do perfil de sensibilidade aos antibióticos, indicando que não houve seleção de resistência adaptativa à prata e de resistência cruzada aos antibióticos pelos micro-organismos estudados. O uso potencial da prata apresentado nos resultados é favorável à continuidade dos estudos objetivando a elaboração de terapias à base de prata para o tratamento da mastite bovina.(AU)

Stx1 and Stx2 subtyping and antimicrobial resistance in Shiga toxin-producing Escherichia coli (STEC) isolates from cattle and sheep feces in the Southeastern region of the State of Goiás, Brazil / Subtipagem de Stx1 e Stx2 e resistência antimicrobiana em isolados de Escherichia coli produtoras de toxina Shiga (STEC) de fezes de bovinos e ovinos na região sudeste de Goiás, Brasil

The present study was aimed at subtyping of Stx1 and Stx2 genes and characterization of antimicrobial resistance in 106 Shiga toxin-producing Escherichia coli (STEC) strains isolated from cattle and sheep feces. PCR was used to determine the subtypes, and the disk-diffusion method was used to evaluate the antimicrobial resistance. Ten antibiotics from five different classes were tested. Among the isolates of bovine origin, two subtypes of Stx1 (Stx1a and Stx1c), and four subtypes of Stx2 (Stx2a, Stx2b, Stx2c, and Stx2d) were identified. In isolates of sheep origin, two subtypes of Stx1 (Stx1a and Stx1c), and four subtypes of Stx2 (Stx2a, Stx2b, Stx2c, and Stx2 g) were identified. The results obtained suggest the presence of high diversity in Stx1 and Stx2 genes. Further, 96.6% (57/59) of bovine fecal strains and 89.4% (42/47) of sheep fecal strains showed resistance to at least one tested antibiotic. In both animal species, most strains were multidrug-resistant (MDR) (67.8% in cattle and 59.6% in sheep), with no significant difference between host animals. Adult animals were eight times more likely to have STEC with greater pathogenic potential. STEC with the highest pathogenic potential were three times more likely to be multidrug-resistant than STEC with the lowest pathogenic potential. The data reported in this study suggests the occurrence of strains with high potential pathogenicity in the region studied. Therefore, the ruminants of this region are carriers of strains that can cause infections in humans.(AU)

O presente estudo teve como objetivo subtipar os genes Stx1 e Stx2 e caracterizar a resistência antimicrobiana em 106 isolados de Escherichia coli produtoras de toxinas Shiga (STEC) isoladas de fezes de bovinos e ovinos. A PCR foi utilizada para determinar os subtipos e o método de difusão em disco foi utilizado para avaliar a resistência antimicrobiana. Dez antibióticos de cinco classes diferentes foram testados. Entre os isolados de origem bovina, foram identificados dois subtipos de Stx1 (Stx1a e Stx1c) e quatro subtipos de Stx2 (Stx2a, Stx2b, Stx2c e Stx2d). Nos isolados de origem ovina, foram identificados dois subtipos de Stx1 (Stx1a e Stx1c) e quatro subtipos de Stx2 (Stx2a, Stx2b, Stx2c e Stx2g). Os resultados obtidos sugerem a presença de alta variabilidade nos genes Stx1 e Stx2. Além disso, 96,6% (57/59) dos isolados fecais de bovinos e 89,4% (42/47) dos isolados de ovinos mostraram resistência a pelo menos um antibiótico testado. Em ambas as espécies animais, a maioria das cepas foi multirresistente (MDR) (67,8% em bovinos e 59,6% em ovinos), sem diferença significativa entre as espécies animais do reservatório. Os animais adultos tiveram oito vezes mais chances de apresentar STEC com maior potencial patogênico. STEC com o maior potencial patogênico teve três vezes mais chances de ser multirresistente do que o STEC com o menor potencial patogênico. Os dados relatados neste estudo sugerem a ocorrência de cepas com alto potencial de patogenicidade na região estudada. Portanto, os ruminantes dessa região são hospedeiros de isolados que podem causar infecções em humanos.(AU)

Stx1 and Stx2 subtyping and antimicrobial resistance in Shiga toxin-producing Escherichia coli (STEC) isolates from cattle and sheep feces in the Southeastern region of the State of Goiás, Brazil / Subtipagem de Stx1 e Stx2 e resistência antimicrobiana em isolados de Escherichia coli produtoras de toxina Shiga (STEC) de fezes de bovinos e ovinos na região sudeste de Goiás, Brasil

The present study was aimed at subtyping of Stx1 and Stx2 genes and characterization of antimicrobial resistance in 106 Shiga toxin-producing Escherichia coli (STEC) strains isolated from cattle and sheep feces. PCR was used to determine the subtypes, and the disk-diffusion method was used to evaluate the antimicrobial resistance. Ten antibiotics from five different classes were tested. Among the isolates of bovine origin, two subtypes of Stx1 (Stx1a and Stx1c), and four subtypes of Stx2 (Stx2a, Stx2b, Stx2c, and Stx2d) were identified. In isolates of sheep origin, two subtypes of Stx1 (Stx1a and Stx1c), and four subtypes of Stx2 (Stx2a, Stx2b, Stx2c, and Stx2 g) were identified. The results obtained suggest the presence of high diversity in Stx1 and Stx2 genes. Further, 96.6% (57/59) of bovine fecal strains and 89.4% (42/47) of sheep fecal strains showed resistance to at least one tested antibiotic. In both animal species, most strains were multidrug-resistant (MDR) (67.8% in cattle and 59.6% in sheep), with no significant difference between host animals. Adult animals were eight times more likely to have STEC with greater pathogenic potential. STEC with the highest pathogenic potential were three times more likely to be multidrug-resistant than STEC with the lowest pathogenic potential. The data reported in this study suggests the occurrence of strains with high potential pathogenicity in the region studied. Therefore, the ruminants of this region are carriers of strains that can cause infections in humans.(AU)

O presente estudo teve como objetivo subtipar os genes Stx1 e Stx2 e caracterizar a resistência antimicrobiana em 106 isolados de Escherichia coli produtoras de toxinas Shiga (STEC) isoladas de fezes de bovinos e ovinos. A PCR foi utilizada para determinar os subtipos e o método de difusão em disco foi utilizado para avaliar a resistência antimicrobiana. Dez antibióticos de cinco classes diferentes foram testados. Entre os isolados de origem bovina, foram identificados dois subtipos de Stx1 (Stx1a e Stx1c) e quatro subtipos de Stx2 (Stx2a, Stx2b, Stx2c e Stx2d). Nos isolados de origem ovina, foram identificados dois subtipos de Stx1 (Stx1a e Stx1c) e quatro subtipos de Stx2 (Stx2a, Stx2b, Stx2c e Stx2g). Os resultados obtidos sugerem a presença de alta variabilidade nos genes Stx1 e Stx2. Além disso, 96,6% (57/59) dos isolados fecais de bovinos e 89,4% (42/47) dos isolados de ovinos mostraram resistência a pelo menos um antibiótico testado. Em ambas as espécies animais, a maioria das cepas foi multirresistente (MDR) (67,8% em bovinos e 59,6% em ovinos), sem diferença significativa entre as espécies animais do reservatório. Os animais adultos tiveram oito vezes mais chances de apresentar STEC com maior potencial patogênico. STEC com o maior potencial patogênico teve três vezes mais chances de ser multirresistente do que o STEC com o menor potencial patogênico. Os dados relatados neste estudo sugerem a ocorrência de cepas com alto potencial de patogenicidade na região estudada. Portanto, os ruminantes dessa região são hospedeiros de isolados que podem causar infecções em humanos.(AU)

Pathological, microbiological and immunohistochemical characterization of avian colibacillosis in broiler chickens of Mozambique / Caracterização patológica, microbiológica e imuno-histoquímica de colibacilose em frangos de corte de Moçambique

Avian colibacillosis is an acute and globally occurring infectious disease of domestic and wild birds caused by Escherichia coli, and it is associated with considerable economic losses mainly due to the morbidity and mortality associated. The present study aimed to describe the pathological, bacteriological and immunohistochemical aspects of avian colibacillosis in broiler chickens of Mozambique. Forty-nine broiler chicken presented anorexia, decreased weight gain, ataxia, diarrhea, dyspnea, and death in a clinical course of 3-5 days. The birds were raised in five farms (small, medium and large farms) with manual and automatic breeding system, with flocks ranging from 100 to 20,000 birds. At the necropsy, all birds had poor body condition, and the pericardium and the Glisson's capsule of all avian exhibited different degrees of adherence often associated with severe fibrin deposition. The thoracic and abdominal air sacs were thickened and adhered to the costal wall. Mild, moderate or marked hepatomegaly associated with white pinpoint multifocal areas (100%, 49/49) and mild to moderate splenomegaly in 75.5% (37/49) with a mottled surface were observed. The lungs and kidney were enlarged and reddish. Histologically, a multiorgan fibrinoheterophilic polyserositis was observed in 75.5% of the cases (37/49), which were characterized by inflammatory infiltrates composed mainly of degenerative heterophils, macrophages and plasma cells, associated with fibrin deposits and intermixed by coccobacillary bacterial basophilic aggregates. These affected mainly the pericardium (28.6%, 14/49), the pleura (18.4%, 9/49), the Glisson's capsule (10.2%, 5/49), the ventriculus (10.2, 5/33), and the proventriculus (8.2%, 4/49) serosa. Multifocal to coalescing areas of coagulative necrosis associated with similar inflammatory cells were observed mainly in the spleen (28.6%, 14/49), liver (24.5%, 12/49), and intestines (22.4%, 11/49). A similar infiltrate was also observed affecting the the lungs (16.3%, 8/49), the kidney (16.3%, 8/49) and the myocardium (14.3%, 7/49). Isolation and identification of E. coli was obtained in 12 cases through bacterial culture. Some organs (2 cases of each farms) were selected and submitted to immunohistochemistry anti-E. coli, and a positive stain was observed in all tested cases in liver (3/3), heart (4/4), spleen (1/1), lungs (4/4), intestines (4/4), bursa of Fabricius (1/1), ventriculus (1/1), and proventriculus (1/1) tissue sections. These results demonstrate that E. coli was the cause of mortality in these birds. Therefore, biosecurity and management measures should be employed to prevent and control the disease occurrence in Mozambique's poultry farming.(AU)

A colibacilose aviária é uma doença aguda de ocorrência mundial que acomete aves domésticas e silvestres, causada por Escherichia coli e resulta em perdas econômicas consideráveis devido à elevada morbidade e mortalidade das aves. O presente estudo teve o objetivo de descrever os aspectos patológicos, bacteriológicos e imuno-histoquímicos de colibacilose aviária em frangos de corte de Moçambique. Um total de 49 frangos de corte apresentaram anorexia, baixo ganho de peso, ataxia, diarreia, dispneia e morte em um curso clínico de 3 a 5 dias. As aves eram provenientes de 5 granjas (pequenas, média e grandes), com sistema de criação manual e automático, com rebanhos que variavam de 100 a 20.000 aves. À necropsia, todas as aves exibiam condição corporal ruim a caquética, além de pericárdio e cápsula de Glisson de todas aves (100%; n=49) com diferentes graus de aderência e deposição de fibrina de forma difusa acentuada. Os sacos aéreos torácicos e abdominais estavam espessados e aderidos à parede costal. Foi observado ainda hepatomegalia discreta, moderada a severa frequentemente associada com áreas multifocais puntiformes brancacentas (100%; 49/49), e esplenomegalia discreta a moderada, associado a áreas multifocais moteadas (75,5%; 37/49). Os pulmões e rins estavam aumentados e com coloração avermelhada. Histologicamente, observou-se majoritariamente serosite fibrinoheterofílica em 75,5% dos casos (37/49), caracterizadas por infiltrado inflamatório composto por heterófilos degenerados, macrófagos, linfócitos e plasmócitos, com deposição de fibrina entremeada por uma miríade de estruturas bacterianas cocobacilares. Esta lesão foi observada principalmente em pericárdio (28,6%; 14/49), pleura (18,4%; 9/49), cápsula de Glisson (10,2%; 5/49), ventrículo (10,2; 5/33) e em proventrículo (8,2%; 4/49). Áreas multifocais a coalescentes de necrose de coagulação associada a infiltrado inflamatório semelhante ao descrito foi observado principalmente no baço (28,6%; 14/49), fígado (24.5%; 12/49), e intestinos (8,2%; 4/49). Um infiltrado inflamatório semelhante também foi visualizado em pulmões (16,3%; 8/49), rins (16,3%; 8/49) e miocárdio (14,3%; 7/49), Colônias puras de E. coli foram identificadas e isoladas em 12 casos. Alguns órgãos (2 de cada granja) foram submetidos ao exame imuno-histoquímico anti-E. coli e marcação positiva foi visualizada em todos casos testados, como em fígado (3/3), coração (4/4), baço (1/1), pulmão (4/4), intestinos (4/4), bursa de Fabricius (1/1), rim (1/1), ventrículo (1/1) e proventrículo (1/1). Estes resultados demonstram que E. coli foi a causa de morte destas aves. Sendo assim, a adoção de boas medidas de biosseguridade e de manejo são indispensáveis para a prevenção e controle da ocorrência da doença nas granjas de frango de corte de Moçambique.(AU)

Pathological, microbiological and immunohistochemical characterization of avian colibacillosis in broiler chickens of Mozambique / Caracterização patológica, microbiológica e imuno-histoquímica de colibacilose em frangos de corte de Moçambique

Avian colibacillosis is an acute and globally occurring infectious disease of domestic and wild birds caused by Escherichia coli, and it is associated with considerable economic losses mainly due to the morbidity and mortality associated. The present study aimed to describe the pathological, bacteriological and immunohistochemical aspects of avian colibacillosis in broiler chickens of Mozambique. Forty-nine broiler chicken presented anorexia, decreased weight gain, ataxia, diarrhea, dyspnea, and death in a clinical course of 3-5 days. The birds were raised in five farms (small, medium and large farms) with manual and automatic breeding system, with flocks ranging from 100 to 20,000 birds. At the necropsy, all birds had poor body condition, and the pericardium and the Glisson's capsule of all avian exhibited different degrees of adherence often associated with severe fibrin deposition. The thoracic and abdominal air sacs were thickened and adhered to the costal wall. Mild, moderate or marked hepatomegaly associated with white pinpoint multifocal areas (100%, 49/49) and mild to moderate splenomegaly in 75.5% (37/49) with a mottled surface were observed. The lungs and kidney were enlarged and reddish. Histologically, a multiorgan fibrinoheterophilic polyserositis was observed in 75.5% of the cases (37/49), which were characterized by inflammatory infiltrates composed mainly of degenerative heterophils, macrophages and plasma cells, associated with fibrin deposits and intermixed by coccobacillary bacterial basophilic aggregates. These affected mainly the pericardium (28.6%, 14/49), the pleura (18.4%, 9/49), the Glisson's capsule (10.2%, 5/49), the ventriculus (10.2, 5/33), and the proventriculus (8.2%, 4/49) serosa. Multifocal to coalescing areas of coagulative necrosis associated with similar inflammatory cells were observed mainly in the spleen (28.6%, 14/49), liver (24.5%, 12/49), and intestines (22.4%, 11/49). A similar infiltrate was also observed affecting the the lungs (16.3%, 8/49), the kidney (16.3%, 8/49) and the myocardium (14.3%, 7/49). Isolation and identification of E. coli was obtained in 12 cases through bacterial culture. Some organs (2 cases of each farms) were selected and submitted to immunohistochemistry anti-E. coli, and a positive stain was observed in all tested cases in liver (3/3), heart (4/4), spleen (1/1), lungs (4/4), intestines (4/4), bursa of Fabricius (1/1), ventriculus (1/1), and proventriculus (1/1) tissue sections. These results demonstrate that E. coli was the cause of mortality in these birds. Therefore, biosecurity and management measures should be employed to prevent and control the disease occurrence in Mozambique's poultry farming.(AU)

A colibacilose aviária é uma doença aguda de ocorrência mundial que acomete aves domésticas e silvestres, causada por Escherichia coli e resulta em perdas econômicas consideráveis devido à elevada morbidade e mortalidade das aves. O presente estudo teve o objetivo de descrever os aspectos patológicos, bacteriológicos e imuno-histoquímicos de colibacilose aviária em frangos de corte de Moçambique. Um total de 49 frangos de corte apresentaram anorexia, baixo ganho de peso, ataxia, diarreia, dispneia e morte em um curso clínico de 3 a 5 dias. As aves eram provenientes de 5 granjas (pequenas, média e grandes), com sistema de criação manual e automático, com rebanhos que variavam de 100 a 20.000 aves. À necropsia, todas as aves exibiam condição corporal ruim a caquética, além de pericárdio e cápsula de Glisson de todas aves (100%; n=49) com diferentes graus de aderência e deposição de fibrina de forma difusa acentuada. Os sacos aéreos torácicos e abdominais estavam espessados e aderidos à parede costal. Foi observado ainda hepatomegalia discreta, moderada a severa frequentemente associada com áreas multifocais puntiformes brancacentas (100%; 49/49), e esplenomegalia discreta a moderada, associado a áreas multifocais moteadas (75,5%; 37/49). Os pulmões e rins estavam aumentados e com coloração avermelhada. Histologicamente, observou-se majoritariamente serosite fibrinoheterofílica em 75,5% dos casos (37/49), caracterizadas por infiltrado inflamatório composto por heterófilos degenerados, macrófagos, linfócitos e plasmócitos, com deposição de fibrina entremeada por uma miríade de estruturas bacterianas cocobacilares. Esta lesão foi observada principalmente em pericárdio (28,6%; 14/49), pleura (18,4%; 9/49), cápsula de Glisson (10,2%; 5/49), ventrículo (10,2; 5/33) e em proventrículo (8,2%; 4/49). Áreas multifocais a coalescentes de necrose de coagulação associada a infiltrado inflamatório semelhante ao descrito foi observado principalmente no baço (28,6%; 14/49), fígado (24.5%; 12/49), e intestinos (8,2%; 4/49). Um infiltrado inflamatório semelhante também foi visualizado em pulmões (16,3%; 8/49), rins (16,3%; 8/49) e miocárdio (14,3%; 7/49), Colônias puras de E. coli foram identificadas e isoladas em 12 casos. Alguns órgãos (2 de cada granja) foram submetidos ao exame imuno-histoquímico anti-E. coli e marcação positiva foi visualizada em todos casos testados, como em fígado (3/3), coração (4/4), baço (1/1), pulmão (4/4), intestinos (4/4), bursa de Fabricius (1/1), rim (1/1), ventrículo (1/1) e proventrículo (1/1). Estes resultados demonstram que E. coli foi a causa de morte destas aves. Sendo assim, a adoção de boas medidas de biosseguridade e de manejo são indispensáveis para a prevenção e controle da ocorrência da doença nas granjas de frango de corte de Moçambique.(AU)

Stx1 and Stx2 subtyping and antimicrobial resistance in Shiga toxin-producing Escherichia coli (STEC) isolates from cattle and sheep feces in the Southeastern region of the State of Goiás, Brazil

ABSTRACT: The present study was aimed at subtyping of Stx1 and Stx2 genes and characterization of antimicrobial resistance in 106 Shiga toxin-producing Escherichia coli (STEC) strains isolated from cattle and sheep feces. PCR was used to determine the subtypes, and the disk-diffusion method was used to evaluate the antimicrobial resistance. Ten antibiotics from five different classes were tested. Among the isolates of bovine origin, two subtypes of Stx1 (Stx1a and Stx1c), and four subtypes of Stx2 (Stx2a, Stx2b, Stx2c, and Stx2d) were identified. In isolates of sheep origin, two subtypes of Stx1 (Stx1a and Stx1c), and four subtypes of Stx2 (Stx2a, Stx2b, Stx2c, and Stx2 g) were identified. The results obtained suggest the presence of high diversity in Stx1 and Stx2 genes. Further, 96.6% (57/59) of bovine fecal strains and 89.4% (42/47) of sheep fecal strains showed resistance to at least one tested antibiotic. In both animal species, most strains were multidrug-resistant (MDR) (67.8% in cattle and 59.6% in sheep), with no significant difference between host animals. Adult animals were eight times more likely to have STEC with greater pathogenic potential. STEC with the highest pathogenic potential were three times more likely to be multidrug-resistant than STEC with the lowest pathogenic potential. The data reported in this study suggests the occurrence of strains with high potential pathogenicity in the region studied. Therefore, the ruminants of this region are carriers of strains that can cause infections in humans.

RESUMO: O presente estudo teve como objetivo subtipar os genes Stx1 e Stx2 e caracterizar a resistência antimicrobiana em 106 isolados de Escherichia coli produtoras de toxinas Shiga (STEC) isoladas de fezes de bovinos e ovinos. A PCR foi utilizada para determinar os subtipos e o método de difusão em disco foi utilizado para avaliar a resistência antimicrobiana. Dez antibióticos de cinco classes diferentes foram testados. Entre os isolados de origem bovina, foram identificados dois subtipos de Stx1 (Stx1a e Stx1c) e quatro subtipos de Stx2 (Stx2a, Stx2b, Stx2c e Stx2d). Nos isolados de origem ovina, foram identificados dois subtipos de Stx1 (Stx1a e Stx1c) e quatro subtipos de Stx2 (Stx2a, Stx2b, Stx2c e Stx2g). Os resultados obtidos sugerem a presença de alta variabilidade nos genes Stx1 e Stx2. Além disso, 96,6% (57/59) dos isolados fecais de bovinos e 89,4% (42/47) dos isolados de ovinos mostraram resistência a pelo menos um antibiótico testado. Em ambas as espécies animais, a maioria das cepas foi multirresistente (MDR) (67,8% em bovinos e 59,6% em ovinos), sem diferença significativa entre as espécies animais do reservatório. Os animais adultos tiveram oito vezes mais chances de apresentar STEC com maior potencial patogênico. STEC com o maior potencial patogênico teve três vezes mais chances de ser multirresistente do que o STEC com o menor potencial patogênico. Os dados relatados neste estudo sugerem a ocorrência de cepas com alto potencial de patogenicidade na região estudada. Portanto, os ruminantes dessa região são hospedeiros de isolados que podem causar infecções em humanos.