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The gut of food-producing animals is a reservoir for foodborne pathogens. Thymol is bactericidal against foodborne pathogens but rapid absorption of thymol from the proximal gut precludes the delivery of effective concentrations to the lower gut where pathogens mainly colonize. Thymol-β-<span style="font-variant: small-caps">d</span>-glucopyranoside is reported to be more resistant to absorption than thymol in everted jejunal segments and could potentially function as a prebiotic by resisting degradation and absorption in the proximal gut but being hydrolysable by microbial β-glycosidase in the distal gut. Previous in vitro studies showed bactericidal effects of thymol-β-<span style="font-variant: small-caps">d</span>-glucopyranoside against <i>Campylobacter</i>, <i>Escherichia coli</i>, and <i>Salmonella enterica</i> serovar Typhimurium in the presence but not absence of intestinal microbes expressing β-glycosidase activity, indicating that hydrolysis was required to obtain antimicrobial activity. Presently, the oral administration of thymol-β-<span style="font-variant: small-caps">d</span>-glucopyranoside was studied to examine the effects on intestinal carriage of <i>Campylobacter</i>, <i>E. coli</i>, and <i>S.</i> Typhimurium in swine. The effects of thymol-β-<span style="font-variant: small-caps">d</span>-glucopyranoside or thymol on antimicrobial sensitivity of representative <i>E. coli</i> isolates and characterized <i>Salmonella</i> strains were also explored. Results from two in vivo studies revealed little antimicrobial effects of thymol-β-<span style="font-variant: small-caps">d</span>-glucopyranoside on <i>Campylobacter</i>, <i>E. coli</i>, or <i>S.</i> Typhimurium in swine gut. These findings add credence to current thinking that hydrolysis and absorption of thymol-β-<span style="font-variant: small-caps">d</span>-glucopyranoside and thymol may be sufficiently rapid within the proximal gut to preclude delivery to the distal gut. Antibiotic susceptibilities of selected bacterial isolates and strains were mainly unaffected by thymol. Further research is warranted to overcome obstacles, preventing the delivery of efficacious amounts of thymol-β-<span style="font-variant: small-caps">d</span>-glucopyranoside to the lower gut.