FIG. 3.

Mean numbers of inoculum bacteria recovered from feces (1 to 4 days p.i.) and tissues (4 days p.i.) from DEX-treated and nontreated weaned calves inoculated intrarumenally or orally with 10¹⁰ CFU of STEC O157:H7 strain 86-24. For the calculation of mean values for “all samples,” samples from which inoculum bacteria were not recovered by direct plating were assigned a value of 1,000 CFU/g of sample. For calculation of mean values for O157⁺ samples, negative results were excluded. Asterisks identify samples with significant differences (P < 0.05, Mann-Whitney test) between means for DEX-treated and nontreated calves.