Fig. 6

Mean relative mouse weights and spore counts after C. difficile VPI10463 challenge. Mice were administered a five-antibiotic cocktail in drinking water ad libitum for 3, 4, or 5 days followed by an IP injection of clindamycin (10 mg kg⁻¹). Twenty-four hours after IP injection, mice were challenged with the high toxin producing strain VPI10463 (n = 6 for each group). Antibiotic and C. difficile control groups showed no signs of weight loss or disease (data not shown). Fecal samples were homogenized in 500 μl PBS and heated to 65 °C for 30 min to kill vegetative cells. Samples were serially diluted and plated in replicate on TCCFA plates to enumerate C. difficile spore numbers. No spores were detected in the negative control group or the no antibiotics control group even with 10⁶ spores administered by gavage (not shown). Shaded area and error bars indicate standard deviation from mean. *6/6 mice became moribund. ND spores non-detectable