No abstract

Serotypes and antimicrobial susceptibility of Salmonella's isolates from broiler production chain were determined. A total of 239 isolated strains from chicken, carcasses, breeding environments, and slaughter was analyzed by disk diffusion test, in the period of 2009 to 2010. For antibiotics with a high number of resistant strains, the minimal inhibitory concentration (MIC) was performed. We identified 24 serotypes, being the most frequent, Minnesota (31.4%) and Infantis (22.6%). The highest percentages of resistance were obtained for sulfonamide (42.7%), followed by tetracycline with 37.6% and amoxicillin with 27.6%. From the total, 32 resistance profiles were identified, being 60.7% of the strains were resistant to at least one antibiotic. Of these, 31.7% of the isolates showed multidrug resistance profiles belonging to serovar Minnesota, Saintpaul, and S. enterica. The highest resistance was found in isolates from slaughterhouse (66.9%) and aviary (58.7%). A large number of strains showed MIC above the maximum tested concentration for the antibiotics amoxicillin and sulfamethoxazole. The high number of Salmonella's resistant strains indicates the need for prudent use of these drugs in poultry production in order to reduce the occurrence and spread of antibiotic resistance profiles, and the risk that multiresistant strains isolated from broilers may pose a risk to human health.

The objective of this study was to characterize the C. jejuni IAL2383 strain isolated from humans in Brazil. Transcripts for the racR, dnaJ and ciaB genes were found and flaA, plda and cadF genes were present in the genome and bacteria was sensitive to most of the important antimicrobials used to treat humans. C. jejuni IAL2383 is a good experimental model to analyze the interactions with cells.

RESUMO Objetivou-se avaliar características de virulência, perfil de resistência antimicrobiana e padrão de similaridade genética de 71 cepas de Salmonella Minnesota isoladas na cadeia produtiva de frangos de corte, entre 2009 e 2010, em duas unidades de uma empresa (A e B). Os isolados foram sorotipificados e submetidos ao teste de susceptibilidade antimicrobiana pelo teste de difusão em disco. Utilizando-se PCR, foi avaliada a presença dos genes invA, lpfA, agfA e sefA e os genes de resistência aos betalactâmicos (bla TEM , bla SHV e bla CTX-M ). A relação filogenética foi determinada por RAPD-PCR. Os maiores percentuais de resistência foram para tetraciclina e sulfonamida. Foram reconhecidos oito perfis de resistência aos antimicrobianos entre as cepas isoladas na indústria A, e 11 perfis de resistência na indústria B. Do total de cepas, 100% foram positivas para o gene invA, 98,6% para o gene agfA, 49,3% para o gene lpfA e nenhuma para o gene sefA. Três cepas foram positivas para o gene bla TEM (4,2%) e 11 (15,5%) para o gene bla CTX-M . A avaliação filogenética demonstrou a presença de sete clusters com similaridade superior a 80% e três perfis distintos. Com base no dendrograma, observou-se a disseminação de um mesmo perfil em ambas as empresas.

This study evaluated the ability of Campylobacter jejuni to penetrate through the pores of the shells of commercial eggs and colonize the interior of these eggs, which may become a risk factor for human infection. Furthermore, this study assessed the survival and viability of the bacteria in commercial eggs. The eggs were placed in contact with wood shavings infected with C. jejuni to check the passage of the bacteria. In parallel, the bacteria were inoculated directly into the air chamber to assess the viability in the egg yolk. To determine whether the albumen and egg fertility interferes with the entry and survival of bacteria, we used varying concentrations of albumen and SPF and commercial eggs. C. jejuni was recovered in SPF eggs (fertile) after three hours in contact with contaminated wood shavings but not in infertile commercial eggs. The colonies isolated in the SPF eggs were identified by multiplex PCR and the similarity between strains verified by RAPD-PCR. The bacteria grew in different concentrations of albumen in commercial and SPF eggs. We did not find C. jejuni in commercial eggs inoculated directly into the air chamber, but the bacteria were viable during all periods tested in the wood shavings. This study shows that consumption of commercial eggs infected with C. jejuni does not represent a potential risk to human health.