title: Prevalence and risk factors associated with Clostridium difficile shedding in veal calves in Italy.
abstract: The aim of this study is to describe the prevalence and risk factors of Clostridium difficile shedding in six farms belonging to two companies in Northern Italy. Four hundred and twenty veal calves, randomly selected and individually identified, were sampled three times: at 0-16, 90-120, and 150 days after introduction. C. difficile was isolated at least once from 87 out of the 420 calves (20.7%). The prevalence of shedding was 20.24% at the first sampling and dropped to 0.72% at the second sampling. None of the samples obtained at 150 days tested positive. Sampling of cecal contents and carcass swabs at slaughter was stratified according to the herd of origin of the animals. C. difficile was never isolated at slaughter, excluding a prevalence higher than 3.5% on the basis of previous investigations. Therefore, in this work, the veal calf could not be confirmed as a potential source of C. difficile for the consumer. Eight different ribotypes (RT) have been described, but the vast majority of the isolates (87.8%) belonged to three ribotypes only: RT-078, RT-012 and RT-126, which are also among the most common of the ribotypes detected in humans in Europe. Most isolates, and all the RT-078 isolates, harbored genes coding for toxins A and B, the binary toxin, and showed a deletion in the gene encoding toxin C, suggesting that the veal calf was a reservoir for epidemic hyper-virulent strains. A correlation between age and shedding was found: the odds ratio (OR) ranged from 2.79 for 36-45 days of age to 4.57 for 13-28 days of age. The presence of diarrhea at first sampling was significantly associated with the recovery of C. difficile in feces (OR 3.26). A correlation was found between the administration of antimicrobials and shedding: an increased risk was shown when the number of antimicrobials used was higher than 4 (OR 4.02) or 5-6 (OR 5.83) or when polymyxin E or beta-lactams were administered.
authors: Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, via Salvemini 1, 06126 Perugia, Italy. Electronic address: c.magistrali@izsum.it.
authors: Chiara Francesca
authors: CF
authors: Magistrali
authors: Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, via Salvemini 1, 06126 Perugia, Italy. Electronic address: c.maresca@izsum.it.
authors: Carmen
authors: C
authors: Maresca
authors: Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, via Salvemini 1, 06126 Perugia, Italy. Electronic address: l.cucco@izsum.it.
authors: Lucilla
authors: L
authors: Cucco
authors: Istituto Zooprofilattico Sperimentale delle Venezie - Treviso, vicolo Mazzini n. 4, Villorba, 31020 Treviso, Italy. Electronic address: lbano@izsvenezie.it.
authors: Luca
authors: L
authors: Bano
authors: Istituto Zooprofilattico Sperimentale delle Venezie - Treviso, vicolo Mazzini n. 4, Villorba, 31020 Treviso, Italy. Electronic address: idrigo@izsvenezie.it.
authors: Ilenia
authors: I
authors: Drigo
authors: Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, via Salvemini 1, 06126 Perugia, Italy. Electronic address: g.filippini@izsum.it.
authors: Giovanni
authors: G
authors: Filippini
authors: Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, via Salvemini 1, 06126 Perugia, Italy. Electronic address: a.dettori@izsum.it.
authors: Annalisa
authors: A
authors: Dettori
authors: Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, via Salvemini 1, 06126 Perugia, Italy. Electronic address: s.broccatelli@izsum.it.
authors: Sayra
authors: S
authors: Broccatelli
authors: Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, via Salvemini 1, 06126 Perugia, Italy. Electronic address: g.pezzotti@izsum.it.
authors: Giovanni
authors: G
authors: Pezzotti
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use; D057138:Bacterial Shedding; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology*; D016360:Clostridioides difficile / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D003967:Diarrhea / Q000662:veterinary; D004761:Enterocolitis, Pseudomembranous / Q000662:veterinary*; D005838:Genotype; D007558:Italy / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors; D065288:Serogroup
chemical_list: D000900:Anti-Bacterial Agents
keywords: Antimicrobial; Clostridium difficile; Diarrhea; Prevalence; Veal calf; Young age