In order to describe the role of wild birds and pigeons in the transmission of shiga toxigenic Escherichia coli (STEC) and enteropathogenic Escherichia coli (EPEC) to humans and other animals, samples were collected from cloacae and oropharynx of free-living wild birds and free-living pigeons. Two STEC (0.8%) and five EPEC strains (2.0%) were isolated from wild birds and four EPEC strains (2.0%) were recovered from pigeons. Serogroups, sequence types (STs) and virulence genes, such as saa, iha, lpfA , ehxA, espA, nleB and nleE, detected in this study had already been implicated in human and animal diseases. Multidrug resistance (MDR) was found in 25.0% of the pigeon strains and in 57.0% of the wild bird strains; the wild birds also yielded one isolate carrying extended-spectrum β-lactamases (ESBLs) gene bla. The high variability shown by PFGE demonstrates that there are no prevalent E. coli clones from these avian hosts. Wild birds and pigeons could act as carriers of multidrug-resistant STEC and EPEC and therefore may constitute a considerable hazard to human and animal health by transmission of these strains to the environment.

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Escherichia coli is a pathogen of major importance in swine and public health. To determine the prevalence of Shiga toxigenic E. coli (STEC) and enteropathogenic E. coli (EPEC), samples were collected from the feces and carcasses of swines. In total, 441 samples were collected in four samplings, of which 141 samples tested positive for either the stx1, stx2, and/or eae genes. From the positive samples, one STEC and 15 atypical EPEC (aEPEC) isolates were obtained, and all originated from the same sampling. In addition to eae, lpfA O157/OI-141 , ehxA, toxB, and lpfA O113 were present in the aEPEC isolates. The only stx2-containing isolate carried stx2e and belonged to serotype O103:HNT. Resistance to four or more antimicrobials was found in almost half of the isolates, and some isolates shared the same fingerprint patterns by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The presence of certain virulence genes and the high level of resistance to antimicrobials, as well as the possible fecal contamination of carcasses showed that some of the isolates are of public health concern.

Avian pathogenic Escherichia coli (APEC) isolates from apparently healthy free range helmeted guineafowl were characterized. Most of them had a high frequency of virulence associated genes, multi drug resistance and high pathogenicity. We demonstrated that helmeted guineafowl have potential to transmit antibiotic resistant APEC to other species including humans.

Dentre os alimentos de origem animal de maior consumo destaca-se o leite e, em particular, o leite tratado por ultra alta temperatura (leite UAT), tendo em vista a sua praticidade de conservação e uso e também seu longo período de vida comercial. No que diz respeito à sua qualidade, a duplicidade de tratamento térmico (pasteurização e processo UAT) aplicada ao produto, devido à má qualidade da matéria-prima, atua desfavoravelmente sobre as propriedades físico-químicas responsáveis pela manutenção do equilíbrio físico do leite (PRATA, 1998). Uma elevada carga de microrganismos mesófilos, psicrotró-ficos e/ou termófilos no leite, através do seu desenvolvimento, degradam constituintes ou produzem substâncias capazes de alterar as propriedades físico-químicas, importantes na manutenção do produto. Matérias-primas de algum modo alteradas experimentarão, quando houver o processo por UAT ou subseqüente armazenamento e comercialização, alterações irreversíveis, modificando e comprometendo a qualidade do produto, ressaltando-se que grande parte das proteínas solú-veis é representada pelas albuminas e globulinas, de conhecida sensibilidade térmica (PRATA, 1998).Antes do tratamento por Ultra Alta Temperatura (UAT), o leite cru deve passar por um tratamento térmico prévio. O processo mais adotado nesta fase é a pasteurização rápida (HTST -73 a 75 °C/15 segundos), como forma de eliminar as bactérias psicrotróficas e as enzimas termosensíveis por elas produzidas (BASTOS, 1999). Nesta fase deve-se avaliar a acidez, a densidade, a gordura e a crioscopia do leite, visando sua liberação para o tratamento por UAT (PRATA, 1998;SANDROW;ARVANITOYANNIS, 2000).No tratamento por UAT o ponto mais importante é o binômio tempo/temperatura, que garante a obtenção de um processo de esterilização comercial. Temperaturas abaixo das estabelecidas são indesejáveis e acima podem causar problemas tecnológicos com alterações das proteínas, interferindo no sabor, geleificação, formação de sedimentos, bloqueio da transferência de calor nas superfícies dos trocadores de calor, AbstractWith the aim of analyzing the physicochemical characteristics of UHT milk during its industrialization and comparing the results with the Brazilian legislation, 150 samples collected in six stages, in different processing phases, were analyzed, being 60 samples of raw milk, 60 of pasteurized milk and 30 of UHT milk. The samples were submitted to the analysis of Dornic acidity, density, fat content, total solids, solids-non-fat, freezing point, pH, methylene blue reduction, stability to 68% alcohol and screening for peroxidase and alkaline phosphatase enzymes. The results indicated that the mean values of total solids and solids-non-fat and freezing point, were in some collections, lower than the limits established in the Brazilian legislation, demonstrating a possible increase in milk water content. Keywords: raw milk; pasteurized milk; UHT milk; physicochemical characteristics. ResumoCom o objetivo de analisar as características físico-químicas do leite UAT durante sua ...

Salmonella Heidelberg is commonly reported in foodborne outbreaks around the world, and chickens and poultry products are known as important source of these pathogen. Multidrugresistant S. Heidelberg strains are disseminated into poultry production chair, which can lead to severe clinical infections in humans and of difficult to treat. This study aimed at evaluating the β-lactam susceptibility and genotypic relatedness of Salmonella Heidelberg at Brazilian poultry production chain. Sixty-two S. Heidelberg strains from poultry production chain (poultry, poultry meat and poultry farm) were used. All strains were evaluated to antimicrobial susceptibility by diffusion disk test, as well as β-lactam resistance genes. Genotypic relatedness was assessed by Pulsed-Field Gel Eletrophoresis, using Xba1 restriction enzyme. Forty-one strains were characterized as multidrug-resistant according to phenotype characterization. The resistance susceptibility revealed 31 distinct profiles, with higher prevalence of streptomycin (61/62), nalidixic acid (50/62), tetracycline (43/62) and β-lactam drugs (37/62). bla CMY-2 was the more frequent β-lactamase gene found (38/62); other resistance genes found were bla CTX-M (2/62), bla SHV (3/62) and bla TEM-1 (38/62). No carbapenemase genes was found. The Pulsed-Field Gel Electrophoresis showed 58 different profiles. Strains with a larger number of antimicrobial resistance were grouped into ten major clusters apart from others. The spread of resistance by ampC continues to rise, thereby turning concern to public health, since the β-lactam antimicrobials are used as a therapeutic treatment in humans.

Shigatoxigenic and enteropathogenic Escherichia coli with virulence and multidrug resistance profile were isolated from Nile tilapia. This study finding is of great importance to public health because they help understand this pathogen epidemiology in fish and demonstrate how these animals can transmit E. coli related diseases to humans.

Salmonella Gallinarum (SG) causes fowl typhoid (FT), a disease responsible for economic losses to the poultry industry worldwide. FT has been considered to be under control in Brazil; nevertheless, since 2012 it has frequently been identified in poultry farming of several Brazilian states. The present study was aimed at assessing (i) the pathogenicity of a SG strain recently isolated from an FT outbreak affecting chickens of both white and brown layers; (ii) the transmission of SG through eggs and hatching; (iii) the effects of antibiotic therapy on SG persistence in poultry tissues and on its vertical transmission and (iv) the genetic profiles of strains isolated over 27 years by Pulsed Field Gel Electrophoresis. Clinical signs, mortality and gross pathologies were very marked amongst brown-egg layers. In contrast, clinical manifestation of FT and mortality were barely present amongst the white-egg layers, although bacteria could be re-isolated from their tissues up to 35 days after infection. No bacteria were re-isolated from the laid eggs, so vertical transmission was not achieved, although newly hatched uninfected chicks became infected spontaneously after hatching. Antibiotic therapy was shown to be effective at reducing mortality, but was not able to clear infection or to favour SG transmission via eggs. Our pulsed field gel electrophoresis results revealed an endemic SG clone that may have been circulating in the Brazilian poultry flocks in the south and southeast regions for more than 20 years. The results suggest that the industrial incubation of SG-contaminated eggs could be one of the factors responsible for the spread of FT in Brazil.