Determination of extended-spectrum β-lactamase-producing isolated from horses with respiratory manifestation.

BACKGROUND AND AIM

The World Health Organization considers multidrug-resistant (MDR) a major global threat. Horses harbor commensal isolates of this bacterial species and potentially serve as reservoirs for human MDR bacteria. This study investigated antimicrobial resistance in horses caused by extended-spectrum β-lactamase (ESBL)-producing .

MATERIALS AND METHODS

One hundred fifty-nine nasal swab samples were collected from horses with respiratory distress not treated with cefotaxime and erythromycin. Biochemical and serological identification was performed on all samples. Polymerase chain reaction (PCR) was used to detect , mucoviscosity-associated gene gA), uridine diphosphate galacturonate 4-epimerase gene e), and iron uptake system gene u), , , and genes. Sequence analysis and phylogenetic relatedness of randomly selected isolates carrying the gene were performed.

RESULTS

Ten isolates of spp. were obtained from 159 samples, with an incidence of 6.28% (10 of 159). Based on biochemical and serological identification, was detected in 4.4% (7 of 159) of the samples. Using PCR, all tested isolates (n=7) carried the gene. By contrast, no isolates carried A, , and genes. The gene was detected in all test isolates. Moreover, all isolates did not harbor the or gene. Sequence analysis and phylogenetic relatedness reported that the maximum likelihood unrooted tree generated indicated the clustering of the test isolate with the other Gram-negative isolate . Finally, the sequence distance of the gene of the test isolate (generated by Lasergene) showed an identity range of 98.4-100% with the gene of the different test isolates.

CONCLUSION

The misuse of antimicrobials and insufficient veterinary services might help generate a population of ESBL-producing in equines and humans, representing a public health risk.