Identification, serotyping and resistance of Salmonella enterica strains isolated from Guinea pigs (Cavia porcellus) clinically ill

The objective was to identify, serotype and determine resistance of Salmonella enterica strains isolated from Guinea pigs clinically ill. These samples were isolated by inoculation in tetrationate broth (Merck) and seeded by depletion in selective media: xylose-lysine-deoxycholate agar (XLD) and Salmonella-Shigella (H.H); the suspect colonies of Salmonella spp. through standard biochemical tests: glucose fermentation, lactose; production of glucose (methyl red) acid, production of urease, Vorges Proskauer, phenylalanine, mobility, use of malonate and Simmons citrate; decarboxylation of arginine, lysine and ornithine; oxidation of gluconic acid and hydrogen sulphide production; was serologically stained by plate agglutination according to the Kauffmann-White antigenic scheme. The determination of the antibacterial resistance pattern was performed according to the Kirby Bauer method, using chloramphenicol (30μg), enrofloxacin (5μg), oxytetracycline (30μg), gentamicin (10μg), trimethoprim sulfamethoxazole (25μg), streptomycin 10μg), fosfomycin (5μg) and furazolidone (100μg). Forty-two strains were isolated and serotyped for 100% Salmonella enterica serovar Typhimurium with antigenic formulas: O4.12: i: 1.2 (78.51%) / O4.12: i: 2 (14.29%) / O4.12: (4.76%) / O4.12: H1.2 (2.38%) the distribution of resistance to antibacterials is relatively low shown mainly by chloramphenicol with 35.7%, oxytetracycline with 26.2% and by Neomycin with 7.1% , among other smaller indices.