The survival of Salmonella sp. in pig slurry submitted to treatment in successive stabilization ponds on a pig-breeding farm was investigated. Furthermore, the isolated Salmonella strains were tested for their resistance against 14 antibiotics, using the agar diffusion method. Of a total of 20 samples taken from different points in the stabilization ponds system, 13 were positive for Salmonella sp. in the beginning and only one at the end of the system. Most of the isolated Salmonella strains (161/163) belonged to sorovar Typhimurium. These strains were resistant to sulfonamide (100%), tetracycline (9.4%), sulfamethoxazole/trimethoprin (84.5%), ampicillin (76.4%), cloramphenicol (29.2%), streptomycin (90.1%), nalidixic acid (77.6%), tobramycin (13.7%), neomycin (5%), amikacin (3.7%), cefaclor (25.5%), gentamicin (6.2%) and amoxacilin/ clavulanic acid (5%). Most Salmonella Typhimurium strains (94.5%) were resistant to 4 or more antibiotics. The multi-resistance level and the pattern variability of these strains were similar in the beginning and at the end of the stabilization ponds system.
Salmonella Typhimurium; antibiotic-resistance; swine; stabilization ponds