title: Natural and experimental infection of neonatal calves with Clostridium difficile.
abstract: Clostridium difficile toxins were associated with calf diarrhea in a recent retrospective study; however, no causal relationship has been prospectively investigated. This infection study tested whether the oral inoculation of neonatal calves with a toxigenic strain of C. difficile (PCR-ribotype 077) results in enteric disease. Fourteen 6-24 h old male colostrums-fed Holstein calves, received either three doses of C. difficile (1.4 x 10(8) +/- 3.5 x 10(8) cfu) (n = 8) or sterile culture broth (n = 6). Calves were euthanized on day 6 or after the onset of diarrhea, whichever came first. Fecal and intestinal samples were blindly cultured for C. difficile, and tested for its toxin A/B (C. difficile TOX A/B II ELISA, Techlab). PCR-ribotyping was used to compare inoculated and recovered isolates. Diarrhea was observed in all control calves and 3/8 of inoculated calves (p = 0.03), but it did not occur in calves that tested positive for C. difficile toxins. Fecal toxins were identified only from two controls. PCR-ribotyping confirmed the presence of C. difficile PCR-ribotype 077 in samples of all inoculated calves, but not from controls. The identification of five other PCR-ribotypes in 3/8 (37.5%) and 2/6 (33.3%) of inoculated and control calves, respectively, indicated early natural infection (< or = 24h of age). Five of 14 cecal samples had C. difficile (p = 0.01). In conclusion, the oral administration of C. difficile PCR-ribotype 077 to neonatal calves resulted in fecal/intestinal colonization but not in detection of toxins, or signs of enteric disease. Further studies are required to investigate the clinical relevance of C. difficile in calves.
authors.affiliation: Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, N1G 2W1 Ontario, Canada. rodriguez-palaci.l@osu.edu
authors.forename: Alexander
authors.initials: A
authors.lastname: Rodriguez-Palacios
authors.forename: Henry R
authors.initials: HR
authors.lastname: Stämpfli
authors.forename: Margaret
authors.initials: M
authors.lastname: Stalker
authors.forename: Todd
authors.initials: T
authors.lastname: Duffield
authors.forename: J Scott
authors.initials: JS
authors.lastname: Weese
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism; D001427:Bacterial Toxins / Q000302:isolation & purification / Q000378:metabolism; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology*; D016360:Clostridioides difficile / Q000378:metabolism / Q000472:pathogenicity*; D003967:Diarrhea / Q000382:microbiology / Q000662:veterinary*; D004761:Enterocolitis, Pseudomembranous / Q000382:microbiology / Q000662:veterinary*; D004768:Enterotoxins / Q000302:isolation & purification* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D007422:Intestines / Q000382:microbiology*; D008297:Male; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011897:Random Allocation; D021521:Ribotyping / Q000662:veterinary
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004768:Enterotoxins; C041348:tcdA protein, Clostridium difficile; C031815:toxB protein, Clostridium difficile