Antimicrobial resistance patterns of Salmonella isolated from finishing pigs and environmental samples

Abstract

<p>The aim of this study was to determine the antimicrobial resistance patterns of Salmonella isolates from pigs and environmental samples collected from modern swine facilities in Brazil. Sixteen samples from a total of 1,026 were positive to Salmonella and six serotypes were identified: Salmonella Typhimurium (1), Salmonella Agona (5), Salmonella Sandiego (4), Salmonella Rissen (1), Salmonella Senftenberg ( 4) and Salmonella Javiana (I). Resistance patterns were different among serotypes, but different isolates from a single serotype had the same antimicrobial pattern. The highest percentage of resistance was to tetracycline (100%), streptomycin (100%), nalidixic acid (100%), cefotaxime (12.5) and tobramycin ( 12.5). All serotypes were I 00% susceptible to ceftriaxone, norfloxacin, ciprofloxacin, ampicillin, gentamycin and chloramphenicol. Intermediate resistance to neomycin (93.5%), amikacin (12.5%) and trimethoprim (12.5%) was seen. The high resistance to tetracycline and streptomycin may be due to its extensive use in pig production.</p>