Antibiotic resistance. The disk diffusion test was
used for determining bacteria susceptibility to
antimicrobials. In this method, standard paper disks
impregnated with known amounts of antibiotics
(10-30 µg) are placed on Muller-Hinton agar. After
48 h incubation, antibiotic activity was determined
by the width of the zone of no growth around the
antibiotic disk. In seven experiments, the most
resistant salmonella was isolated for transmission
study