Valoración de los perfiles antimicrobianos y genes de resistencia de Salmonella enterica aislada en carne de pollo expendida en Ambato”

Abstract

Salmonella enterica is a versatile bacteria that perceives very refined antimicrobial resistance mechanisms, causing a worldwide problem with regard to public health, which is why it should be investigated according to the “One Health” approach, which unites human, animal and environmental health professionals to mitigate the development of bacterial resistance, because the routes of contamination of these bacteria are through foods of animal origin, whose spread is more effective due to the poor hygiene standards implemented in slaughter sites. The objective of this research was to assess the antimicrobial profiles and resistance genes of Salmonella enterica isolated in chicken meat sold in Ambato. A Salmonella enterica strain was used, from which two samples were obtained (Salmonella enterica subespecie enterica serovar Enteritidis strain ATCC 13076 and Salmonella enterica strain FDAARGOS_768), where they were developed in two study phases. In the first phase, the use of the Kirby Bauer method was highlighted to evaluate the antibioresistance of the strain against a group of 5 antibiotics, these being Amoxicillin plus clavulanic acid (AMC), Ciprofloxacin (CIP), Gentamicin (GM), Oxytetracycline (OT) and Sulfamethoxazole plus trimethoprim (SXT), of which were classified according to the size of their inhibition zone into Resistant, Intermediate and Sensitive, following the regulations imposed by the CLSI. The results obtained were total resistance to OT, intermediate resistance to CIP and sensitivity to GM, AMC and SXT, the latter acting effectively against Salmonella enterica. In the second phase, only Oxytetracycline was taken to observe the presence of resistance genes, since it was the only antibiotic that was resistant. To visualize the resistance genes, the tet(4) gene primers were used, due to the high prevalence rate in previous research, and the same PCR conditions with which the gene was obtained were also applied. However, the results were negative without the presence of the chosen gene, for this reason it was considered pertinent to explain the molecular mechanisms that confer resistance to the bacteria against each group of antibiotics, starting with tetracyclines and ending with sulfonamides.