Antibiotic Resistance in the Alternative Lifestyles of Campylobacter jejuni.

Campylobacter jejuni is the main pathogen identified in cases of foodborne gastroenteritis worldwide. Its importance in poultry production and public health is highlighted due to the growing antimicrobial resistance. Our study comparatively investigated the effect of five different classes of antimicrobials on the planktonic and biofilm forms of 35 strains of C. jejuni with high phylogenetic distinction in 30 of them. In the planktonic form, the existence of susceptible strains to colistin (7/35 - 20%) and resistance to meropenem (3/35 - 8.6%) represent a novelty in strains evaluated in Brazil. In biofilms formed with the addition of chicken juice, the number of resistant strains was significantly higher for colistin, erythromycin and meropenem (100%), but the susceptibility to tetracycline was shown as a control strategy for specific cases. High concentrations (1,060 ± 172.1mg/L) of antibiotics were necessary to control the biofilm structure in susceptible strains in the planktonic form, which is consistent with the high biomass produced in these strains. Stainless steel and polyurethane were the most (BFI=2.1) and least (BFI=1.6) favorable surfaces for the production of biomass treated with antimicrobials. It is concluded that the antimicrobial action was detected for all tested drugs in planktonic form. In sessile forms, the biomass production was intensified, except for tetracycline, which showed an antibiofilm effect.

Diversity and antimicrobial resistance of Salmonella isolated from swines feces and carcasses / Diversidade e resistência aos antimicrobianos de Salmonella isoladas de fezes e carcaças de suínos

The aim of this study was to determine the most frequent Salmonella serovars in swine feces in the farm, piggerys waiting slaughterhouse and after in their carcasses during slaughter, as well as their antimicrobial resistance profiles. Eighty six strains of Salmonella spp. were used, they were previously isolated from three different lots in different collections. The identification of serovars was done by serotyping and the resistance to antimicrobial agents was determined by disc diffusion. A variety of serovars was observed, and the 86 strains were serologically identified as: 28 (32.55%) S. Typhimurium, 20 (23.26%) S. Agona, 17 (19.77%) S. Infantis, 6 (6.98%) S. Panama, and 15 (17.44%) S. Minnesota. The diversity of serovars indicated that different factors influence the infection of finishing pigs and the persistence of microorganisms in the carcass after slaughter of these animals. More than 50% of the isolates were resistant to nine of the 11 tested antibiotics. The drugs that microorganisms had the highest percentages of sensitivity were sulphazotrim and norfloxacin, 22.1% and 14%, respectively. S. Typhimurium serovar was the most isolated, including in the carcasses, and also showed the largest difference in antimicrobial resistance when compared to other serovars. The profile of multidrug resistance observed in this study highlights to the necessity of a judicious observation of antimicrobial resistance in zoonotic foodborne bacteria.(AU)

Objetivou-se determinar os sorovares de Salmonella mais freqüentes em fezes de suínos na granja de terminação, pocilga de espera do frigorífico e em suas carcaças durante o abate, assim como, seus perfis de resistência aos antimicrobianos. Utilizou-se 86 cepas de Salmonella spp previamente isoladas de três lotes diferentes em coletas distintas. A identificação dos sorovares foi realizada por meio de sorotipificação e a resistência aos antimicrobianos foi determinada pela técnica de difusão de discos. Foi observada uma multiplicidade de sorovares, sendo as 86 cepas identificadas sorologicamente como: 28 (32,55%) S. Typhimurium, 20 (23,26%), S. Agona, 17 (19,77%) S. Infantis, 6 (6,98%) S. Panama, e 15 (17,44%) S. Minnesota. A diversidade de sorovares indicou que diferentes fatores influenciam na infecção de suínos em terminação e na persistência do microrganismo na carcaça destes animais após o abate. Mais de 50% dos isolados apresentaram resistência a nove dos 11 antibióticos testados. As drogas as quais os microrganismos apresentaram os maiores percentuais de sensibilidade foram o sulfazotrim e a norfloxacina, 22,1% e 14%, respectivamente. S. Typhimurium foi o sorovar mais isolado, inclusive nas carcaças, e também o que demonstrou maior diferença quanto à resistência aos antimicrobianos, quando comparado aos outros sorovares. O perfil de multirresistência observado neste estudo alerta para a necessidade de vigilância e monitoramento sistemático da resistência aos antimicrobianos em bactérias zoonóticas transmitidas pelos alimentos.(AU)

Diversity and antimicrobial resistance of Salmonella isolated from swines feces and carcasses / Diversidade e resistência aos antimicrobianos de Salmonella isoladas de fezes e carcaças de suínos

The aim of this study was to determine the most frequent Salmonella serovars in swine feces in the farm, piggery’s waiting slaughterhouse and after in their carcasses during slaughter, as well as their antimicrobial resistance profiles. Eighty six strains of Salmonella spp. were used, they were previously isolated from three different lots in different collections. The identification of serovars was done by serotyping and the resistance to antimicrobial agents was determined by disc diffusion. A variety of serovars was observed, and the 86 strains were serologically identified as: 28 (32.55%) S. Typhimurium, 20 (23.26%) S. Agona, 17 (19.77%) S. Infantis, 6 (6.98%) S. Panama, and 15 (17.44%) S. Minnesota. The diversity of serovars indicated that different factors influence the infection of finishing pigs and the persistence of microorganisms in the carcass after slaughter of these animals. More than 50% of the isolates were resistant to nine of the 11 tested antibiotics. The drugs that microorganisms had the highest percentages of sensitivity were sulphazotrim and norfloxacin, 22.1% and 14%, respectively. S. Typhimurium serovar was the most isolated, including in the carcasses, and also showed the largest difference in antimicrobial resistance when compared to other serovars. The profile of multidrug resistance observed in this study highlights to the necessity of a judicious observation of antimicrobial resistance in zoonotic foodborne bacteria.

Objetivou-se determinar os sorovares de Salmonella mais freqüentes em fezes de suínos na granja de terminação, pocilga de espera do frigorífico e em suas carcaças durante o abate, assim como, seus perfis de resistência aos antimicrobianos. Utilizou-se 86 cepas de Salmonella spp previamente isoladas de três lotes diferentes em coletas distintas. A identificação dos sorovares foi realizada por meio de sorotipificação e a resistência aos antimicrobianos foi determinada pela técnica de difusão de discos. Foi observada uma multiplicidade de sorovares, sendo as 86 cepas identificadas sorologicamente como: 28 (32,55%) S. Typhimurium, 20 (23,26%), S. Agona, 17 (19,77%) S. Infantis, 6 (6,98%) S. Panama, e 15 (17,44%) S. Minnesota. A diversidade de sorovares indicou que diferentes fatores influenciam na infecção de suínos em terminação e na persistência do microrganismo na carcaça destes animais após o abate. Mais de 50% dos isolados apresentaram resistência a nove dos 11 antibióticos testados. As drogas as quais os microrganismos apresentaram os maiores percentuais de sensibilidade foram o sulfazotrim e a norfloxacina, 22,1% e 14%, respectivamente. S. Typhimurium foi o sorovar mais isolado, inclusive nas carcaças, e também o que demonstrou maior diferença quanto à resistência aos antimicrobianos, quando comparado aos outros sorovares. O perfil de multirresistência observado neste estudo alerta para a necessidade de vigilância e monitoramento sistemático da resistência aos antimicrobianos em bactérias zoonóticas transmitidas pelos alimentos.