A total of 204 strains of Staphylococcus hyicus subsp. hyicus isolated from piglets suffering from exudative epidermitis and healthy pigs were tested for antibiotic susceptibility. The growth of all isolates of Staph. hyicus subsp. hyicus tested was inhibited by cloxacillin (Cx) at a concentration of 0.8㎍/㎖ and by cefazolin (Cf) at a concentration of 0.4㎍/㎖, and by gentamicin and methicillin at a minimum inhibitory concentration of 3.2㎍/㎖.
Of total isolates obtained from the diseased and healthy pigs, 69.6% were resistant to penicillin G, 53.4% to tetracycline, 11.8% to kanamycin and 0.5% to chloramphenicol, with considerable variations among farms in the occurrence of resistant strains and resistance patterns to the drugs.
By application of Cx or Cf which was active to the organism, piglets exposed to infection were successfully protected from the disease, but piglets suffering from already severe exudative epidermitis did not respond to treatment.
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