title: Susceptibility to enteric botulinum colonization of antibiotic-treated adult mice.
abstract: The relationship between the indigenous intestinal microflora of adults and their resistance to the enteric botulinum infection of infant botulism was studied. Orogastric challenges of 10(5) type A Clostridium botulinum spores were given to adult mice whose gut flora had been altered by feedings of a mixture of erythromycin and kanamycin sulfate. From 80 to 100% of mice became infected when challenged 15 to 60 h after antibiotic administration. The mean infective dose of 2 X 10(4) spores per mouse for challenges given 23 h after antibiotic administration contrasted with the failure of 10(6) spores to infect control mice. Botulinum-colonized mice remained asymptomatic, although colonization lasted up to 5 days, and total botulinum toxin in the gut on days 3 and 4 postchallenge averaged 3,400 and 2,200 mouse intraperitoneal mean lethal doses. The mean infective dose for inocula placed in the colon of antibiotic-treated mice was 10(3) spores per mouse, and C. botulinum multiplied in the cecum as well as in the colon.
mesh_terms: D018407:Bacterial Physiological Phenomena; D001905:Botulinum Toxins / Q000032:analysis; D001906:Botulism / Q000276:immunology* / Q000382:microbiology; D003014:Clostridium botulinum / Q000254:growth & development*; D004917:Erythromycin / Q000494:pharmacology; D007113:Immunity, Innate; D007420:Intestine, Large / Q000382:microbiology*; D007612:Kanamycin / Q000494:pharmacology
chemical_list: D007612:Kanamycin; D004917:Erythromycin; D001905:Botulinum Toxins