Aureomycin and Terramycin Treatment of Pasteurella multocida Infection and Neomycin's in vitro Effects on P. multocida

Abstract

Both aureomycin and terramycin, admd. subcut., either prophylactically or therapeutically 4 hours after infection to white mice infected intraperit. with 1000 MLD100 of P. multocida, prolonged survival and lowered the fatality rate. Aureomycin was distinctly superior to terramycin; a single dose of 2 mg. (133 mg./kg.) resulted in a survival rate of approx. 87%, whereas that of the mice treated with terramycin was approx. 47%. Smaller doses (1 mg. and less) of both antibiotics were less effective. Treatment over a period of 6 days did not increase substantially the survival rate as compared to a single dose treatment on day of infection. In vitro, neomycin was of the same bacteriostatic potency as streptomycin against 7 strains of P. multocida and was markedly superior against the 8th, streptomycin-resistant, strain.