Three sources of inoculum were examined using TKT medium for detection of Streptococcus agalactiae from a herd of low prevalence of infection. An inoculum of a loopful (0.01 ml) from a bulk milk sample yielded a 3.6% recovery rate. An inoculum of gravity cream from bulk tank samples yielded a 36.5% recovery rate. In a third technique, a loopful of rinsings from the filter pad, through which a complete milking had been filtered, yielded a 62.0% recovery rate.
1Supported in part by Public Health Service Research Grant No. UI 00124 from the National Center for Urban and Industrial Health.
2Published with the approval of the Wisconsin Agricultural Experiment Station as paper N.S. No. 599.
3The authors wish to thank Miss Karen Mandt for assistance in the laboratory.