The Brazilian state of Mato Grosso is the largest producer and exporter of beef in the country, but few studies of relevance have been conducted to evaluate the microbiological safety of its products. This study aimed to estimate the prevalence of Listeria monocytogenes (LM) in export-approved beef from Mato Grosso and to characterize the isolates in terms of molecular properties and antimicrobial resistance. From a total of 50 samples analyzed, Listeria sp. was isolated in 18 (36% prevalence). Listeria monocytogenes was confirmed in 6 (12% prevalence). Among the serotype groups assessed by multiplex PCR, serotype 4 (4b, 4d or 4e) was the most prevalent. Although antibiotic resistance was not an issue, two strains isolated from different plants showed high resistance to sodium hypochlorite. Overall, this scenario causes concern because it puts at risk not only the Brazilian customer, but also the population of countries that import beef from Mato Grosso.

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Introduction: Salmonella spp. is a pathogen associated with foodborne infections, mainly in foods of animal origin. In this context, the present study investigated the occurrence of Salmonella serotypes, genotypes and the antimicrobial resistance profiles of strains in fresh beef produced in Mato Grosso, Brazil. Methodology: A total of 107 samples from 13 different slaughterhouses in the Mato Grosso were analyzed. Suggestive Salmonella spp. colonies detected during the biochemical screening were submitted to DNA extraction, and hilA gene amplification was used for the PCR reaction. Antimicrobial resistance analyses were performed using 17 antimicrobial agents from eight different classes by the disk diffusion method. Strains exhibiting multiple drug resistances were submitted to PCR genotyping based on repetitive sequences (rep-PCR), using a commercial semiautomatic DiversiLab® system. Results: A total of 5.6% (6/107) of the samples tested positive by the conventional method and were confirmed by PCR, namely two S. Akuafo, two non-typable Salmonella enterica strains, one Salmonella O:16 serovar, and one S. Schwarzengrund. The antimicrobial resistance profiles indicated resistance to gentamicin (30%), tetracycline, nitrofurantoin, and trimethoprim + sulfamethoxazole (16%). Genotyping indicated a 70% difference between S. Schwarzengrund and the non-typable Salmonella strains. No genetic similarities were observed between the six Salmonella isolates based on rep-PCR, including two S. Akuafo. Conclusions: The results obtained herein corroborate that Salmonella serovar Schwarzengrund is commonly isolated in animal products in the state of Mato Grosso, Brazil, also highlighting the presence of two unusual Salmonella serovars in beef (Akuafo and O:16).

Pork and products thereof are known important sources of Salmonella to humans with particular concern to S. Typhimurium and S. Derby. The purpose of this work is to present potential risk factors for Salmonella Derby or S. Typhimurium in feces in Danish breeding pig herds, using data from the EU baseline survey on prevalence of Salmonella in breeding pigs, 2008. Multi-level multivariable analysis including 2930 pens (12 variables) within 293 holdings (7 variables) was carried in SPSS version 22 using GLMM. Three outcomes were assessed, based on Salmonella positivity or negativity of the pens' fecal pools: one binomial (Salmonella positive or negative pool); two multinomial outcomes, one with S. Typhimurium positive or S. non-Typhimurium positive or Salmonella negative pools and the other with S. Derby positive or S. non-Derby positive or Salmonella negative pools. Potential risk factors (p<0.05) for Salmonella positivity were: total number of breeding pigs, boar replacement policy and type of feed; S. Typhimurium-dependent potential risk factors were boar replacement policy and type of feed; S. Derby-dependent potential risk factors were boar replacement policy, type of feed and source of feed. The results from our analysis for Salmonella spp are in line with the conclusions from the EFSA report at the EU-level. Differences are that fewer associations were found in Danish data, with the variable boar replacement policy being retained in all three final models. A similar association was found in Portugal, which was source of semen. Results from Denmark and Portugal retained potential similar associations but full comparability was not possible due to some differences in the statistical methodology. Serotype-specific risk factor investigation revealed different risk associations for S. Typhimurium in Portugal and Denmark. Serotype-specific risk associations for S. Typhimurium and S. Derby in Denmark showed some differences which will be discussed.