the supernatant was decanted. The pellet was
washed twice with 10 ml of 0.1% peptone water (Becton, Dickinson
and Company, Sparks, MD) and resuspended in 10 ml of 0.1%
peptone water for final use. Tryptic soy agar (TSA; Becton, Dickinson
and Company, Sparks, MD) with 100 mg/ml rifampicin (TSAR)
was used to enumerate Salmonella. Resuspended cultures were
serially diluted with 0.1% peptone water and enumerated to verify
the initial concentration. Resuspended cultures contained approximately
108e109 CFU/ml Salmonella.