title: Quantitative real-time PCR for detection of neurotoxin genes of Clostridium botulinum types A, B and C in equine samples.
abstract: Botulism in horses in the USA is attributed to Clostridium botulinum types A, B or C. In this study, a duplex quantitative real-time PCR (qPCR) for detection of the neurotoxin genes of C. botulinum types A and B, and a singleplex qPCR for detection of the neurotoxin gene of C. botulinum type C, were optimized and validated for equine gastrointestinal, faecal and feed samples. The performance of these assays was evaluated and compared to the standard mouse bioassay (MBA) using 148 well-characterized samples, most of which were acquired from a repository of veterinary diagnostic samples from cases of botulism: 106 samples positive for C. botulinum (25 type A, 27 type B, 28 type C, 1 type D and 25 type E) and 42 negative samples. The sensitivities of the qPCR assays were 89%, 86% and 96% for C. botulinum types A, B and C, respectively. The overall sensitivity of the mouse bioassay for types A, B and C was 81%. The specificities of the qPCR assays were 99-100% and the specificity of the mouse bioassay was 95%.
authors.affiliation: Department of Clinical Studies, New Bolton Center, University of Pennsylvania School of Veterinary Medicine, Kennett Square, PA 19348, USA. Electronic address: amyjohn@vet.upenn.edu.
authors.forename: Amy L
authors.initials: AL
authors.lastname: Johnson
authors.affiliation: Department of Clinical Studies, New Bolton Center, University of Pennsylvania School of Veterinary Medicine, Kennett Square, PA 19348, USA.
authors.forename: Susan C
authors.initials: SC
authors.lastname: McAdams-Gallagher
authors.affiliation: Department of Clinical Studies, New Bolton Center, University of Pennsylvania School of Veterinary Medicine, Kennett Square, PA 19348, USA.
authors.forename: Raymond W
authors.initials: RW
authors.lastname: Sweeney
mesh_terms: D000818:Animals; D001681:Biological Assay; D047013:Clostridium botulinum type A / Q000235:genetics*; D047014:Clostridium botulinum type B / Q000235:genetics*; D047968:Clostridium botulinum type C / Q000235:genetics*; D006736:Horses; D051379:Mice; D009498:Neurotoxins / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*
chemical_list: D009498:Neurotoxins
keywords: Botulism; Equine; Mouse bioassay; Real-time quantitative PCR