| Popis: |
Purpose: The aim of this study was to analyze in S. Minnesota the presence of virulence genes, phylogenetic relationship, biofilm formation index (BFI) and its ultrastructure at temperatures of 4 °C, 25 °C and 36 °C and also the ability of biocidal agents to promote inhibition of the sessile structure formed by 20 strains isolated in the years 2009, 2010 and 2014 in broiler slaughter plants of two Brazilian companies.Methods: The presence of specific genes was evaluated by PCR and the phylogeny between the strains by PFGE, while BFI was performed by the classical method using TSB broth supplemented with 5% of chiken juice and its structure observed by SEM Chlorhexidine 1%, sodium hypochlorite 1% and peracetic acid 0.8% were tested for biofilm inhibition.Results: The presence of specific genes indicates that S. Minnesota has the potential to cause disease in humans and to adapt to adverse conditions. In general, temperatures of 25 °C and 36 °C favored more biofilm formation, although at 4 °C there is still biomass with potential contaminant from the final product. Tolerant strains (12/20–60%) to all biocides pose a real risk for the development of adaptation mechanisms, especially for resistance to sodium hypochlorite. Phylogenetic analysis indicated the existence of cross contamination problems and the spread among companies, probably related to the formation of biofilms.Conclusion: The results show the necessity of attention to this serovar considering its resistance to sodium hypochlorite in addition to the need for rigorous monitoring and control measures based on the adoption of low temperatures in order to prevent the formation of biofilms in the poultry industry. |
