in the use of this radiometric method is feasible
with an instrument such as the Bactec model
301 instrument (Johnston Laboratories Inc.,
Cockeysville, Md.) used by Lampi et al. (8). The
time for detection of Salmonella can be reduced
in many cases to less than 7 h by the regular
monitoring of '4CO2 provided by such an instrument.
The cost per sample of ['4C]dulcitol and
the Salmonella poly H agglutinating serum is
minimal. In our experience the overall cost per
sample for the radiometric method compares
favorably with the cost of using the conventional
cultural methods because of the savings in media,
labor, and time associated with use of the
radiometric method.