title: Identification of risk factors influencing Clostridium difficile prevalence in middle-size dairy farms.
abstract: Farm animals have been suggested to play an important role in the epidemiology of Clostridium difficile infection (CDI) in the community. The purpose of this study was to evaluate risk factors associated with C. difficile dissemination in family dairy farms, which are the most common farming model in the European Union. Environmental samples and fecal samples from cows and calves were collected repeatedly over a 1 year period on 20 mid-size family dairy farms. Clostridium difficile was detected in cattle feces on all farms using qPCR. The average prevalence between farms was 10% (0-44.4%) and 35.7% (3.7-66.7%) in cows and calves, respectively. Bacterial culture yielded 103 C. difficile isolates from cattle and 61 from the environment. Most C. difficile isolates were PCR-ribotype 033. A univariate mixed effect model analysis of risk factors associated dietary changes with increasing C. difficile prevalence in cows (P = 0.0004); and dietary changes (P = 0.004), breeding Simmental cattle (P = 0.001), mastitis (P = 0.003) and antibiotic treatment (P = 0.003) in calves. Multivariate analysis of risk factors found that dietary changes in cows (P = 0.0001) and calves (P = 0.002) increase C. difficile prevalence; mastitis was identified as a risk factor in calves (P = 0.001). This study shows that C. difficile is common on dairy farms and that shedding is more influenced by farm management than environmental factors. Based on molecular typing of C. difficile isolates, it could also be concluded that family dairy farms are currently not contributing to increased CDI incidence.
authors.affiliation: Veterinary faculty, University of Ljubljana, cesta v Mestni log 47, 1115, Ljubljana, Slovenia. petra.bandelj@vf.uni-lj.si.
authors.forename: Petra
authors.initials: P
authors.lastname: Bandelj
authors.affiliation: Institute for biostatistics and Medical informatics, University of Ljubljana, Vrazov trg 2, 1104, Ljubljana, Slovenia.
authors.forename: Rok
authors.initials: R
authors.lastname: Blagus
authors.affiliation: , Vodnikova cesta 243, 1000, Ljubljana, Slovenia.
authors.forename: France
authors.initials: F
authors.lastname: Briski
authors.affiliation: , Vinharje 6, 4223, Poljane nad Skofjo Loko, Slovenia.
authors.forename: Olga
authors.initials: O
authors.lastname: Frlic
authors.affiliation: Veterinary faculty, University of Ljubljana, cesta v Mestni log 47, 1115, Ljubljana, Slovenia.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Vergles Rataj
authors.affiliation: National Laboratory for Health, Environment and Food, Prvomajska ulica 1, 2000, Maribor, Slovenia.|Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia.|Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova cesta 39, 1000, Ljubljana, Slovenia.
authors.forename: Maja
authors.initials: M
authors.lastname: Rupnik
authors.affiliation: Veterinary faculty, University of Ljubljana, cesta v Mestni log 47, 1115, Ljubljana, Slovenia.
authors.forename: Matjaz
authors.initials: M
authors.lastname: Ocepek
authors.affiliation: Veterinary faculty, University of Ljubljana, cesta v Mestni log 47, 1115, Ljubljana, Slovenia.
authors.forename: Modest
authors.initials: M
authors.lastname: Vengust
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology; D016360:Clostridioides difficile / Q000145:classification / Q000502:physiology*; D003015:Clostridium Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D003612:Dairying; D005243:Feces / Q000382:microbiology; D005260:Female; D016133:Polymerase Chain Reaction / Q000662:veterinary; D015995:Prevalence; D012307:Risk Factors; D017524:Slovenia / Q000453:epidemiology