ABSTRACT This study aimed to analyze 19 isolates of Salmonella spp., from broiler litter swabs in the State of São Paulo, by typing and analyzing the detection of resistance genes associated with ESBL’s (Extended Spectrum Beta Lactamase), AMPC (C-type cephalosporinases) and carbapenemases by molecular and phenotypic techniques. A PCR microarray platform (Check and Trace by Check-Points) was used to identify the isolated serotype. The isolates were also evaluated for identification of carbapenemase genes, MCR 1-2 (colistin resistance), AmpC (C-type cephalosporins), and ESBLs (β-lactamases resistance). To identify phenotypic antibiotic resistance, the minimal inhibitory concentration (MIC) was evaluated with the antibiotics meropenem, amoxicillin, and ceftriaxone. The most prevalent serotypes identified were S. Infantis and S. Saintpaul, with a prevalence of 15.07% (3/19). Other strains identified were S. Cerro, S. Sandiego, S. Kentucky, S. Alachua, S. Javiana, S. Livingstone, S. Typhimurium, S. Heidelberg, non-enteric Salmonella, and a Salmonella not typifiable by the typing kit. All samples were negative for identifying carba resistance genes, MCR, ESBL, and AmpC. In the phenotypic profile, meropenem was the least resistant, while amoxicillin and ceftriaxone showed a high resistance pattern. The results show that phenotypic resistance is not associated with the presence of resistance genes studied here. In addition, the resistant bacteria found in MIC have resistance mechanisms not associated with the genes studied here. Additional measures must be implemented to prevent the indiscriminate use of antimicrobial agents therapeutically or as growth promoters.

ABSTRACT The analysis of Salmonella in the feces and the birds’ environment is a way of monitoring the colonization in the flocks and verifying the need for the introduction of stricter controls, in such a way that the results of the tests should be known before being sent for slaughter. The polymerase chain reaction (PCR), as well as other rapid methods represent alternatives increasingly used to detect enteric pathogens, but they need proof of effectiveness for their wide use. The aim of this study was to evaluate the equivalence between the results obtained by the methods: real-time PCR (BAX® System), Modified Rappaport-Vassiliadis Semi-solid Medium (MSRV) (ISO 6579) and the traditional method of official reference in Brazil for research of S. Typhimurium and S. Enteritidis in poultry samples. Two hundred and fifty-two samples of disposable shoe covers (DSC) and 252 samples of feces were infected with an average of 2 to 3 log CFU/g of each serovar, and the same samples without fortification were evaluated by the three methods. Five hundred and four diagnoses were obtained with satisfactory results in terms of repeatability (greater than 80%), reproducibility (mean 83,1%), sensitivity (81% to 100%), specificity (95% to 100%), and accuracy (90% to 100%). The compliance test verified that there was not a significant difference between the alternative and the official methods, allowing us to state that the methodologies have had equivalent performances.

ABSTRACT This study aimed to evaluate the efficacy of biofilms formed by lactic acid bacteria and Bacillus sp. (BLA) in preventing and controlling the formation of wild biofilms and/or planktonic forms of Salmonella Gallinarum (SG), Salmonella Heidelberg (SH), and methicillin-resistant Staphylococcus aureus (MRSA) on different surfaces. The SH and SG viability was evaluated in polystyrene plates, wood shavings, and soil samples. Two protocols were developed to examine the use of BLA in a preventive and control application. For analysis of Campylobacter jejuni (CJ) BLA was used only preventively in a polystyrene plate. Results showed that BLA was effective in preventing the growth of SG and SH in all matrices. The effectiveness of BLA for MRSA was lower than for SG and SH. The efficiency of BLA in preventing CJ growth seems to be related to the initial CJ contamination. BLA proves to be a potential alternative to control food-borne pathogens commonly encountered in animal production and food industry.