A. Kobe et al., MINIMUM INHIBITORY CONCENTRATIONS OF INTESTINAL ESCHERICHIA-COLI FROMBROILER-CHICKENS AFTER ORAL-ADMINISTRATION OF APRAMYCIN, Journal of Applied Bacteriology, 80(1), 1996, pp. 26-30
This study describes the influence of apramycin on minimum inhibitory
concentrations (MIG) of intestinal Escherichia coli in young broiler c
hickens, after oral administration of the antibiotic at a dosage equiv
alent to a prophylactic course of treatment for 10 d. The bacteria wer
e isolated from cloacal swabs and caecal contents. MICs were determine
d by agar dilution procedures. MIC of npl am! cin for the investigated
strains ranged from 1 mu g ml(-1) to 16 mu g ml(-1). Strains obtained
from undosed birds mainly had MIC values of 2 mu g ml(-1). MIC values
of 8 mu g ml(-1) or more were recorded only among isolates obtained f
rom chickens which had received apramycin. Administration of apramycin
resulted in a slight but statistically significant increase in the av
erage MIG. Statistically higher average MICs were recorded among isola
tes from cloacal swabs 10 d after withdrawal until the end of the expe
riment. For strains from caecal contents, this was demonstrated only o
n one sampling occasion, 15 d after withdrawal.