Abstract
The therapeutic efficacy of a 1 : 3 combination of ormetoprim-sulfamonomethoxine (OMPSMM), oxolinic acid (OA), and miloxacin (MLX) was evaluated against drug resistant strains of Edwardsiella tarda. These resistant strains carried on R plasmid encoded with resistance to chloramphenicol, tetracycline, and sulfonamide. Fish were injected intraperitoneally with the bacterium and orally dosed with various level of OMP-SMM, OA, and MLX for five days. Appropriate positive and negative controls were incoporated into the study. A dose of at least 25 mg/kg/day of a combination of OMP-SMM, 12.5 mg of OA, and 6.2 mg of MLX provided protection. Our results indicated that OMP-SMM, OA, and MLX were effective against the infection with drug resistant strain of E. tarda.
