title: Outbreak of Type C Botulism in Commercial Layer Chickens.
abstract: This report describes an outbreak of type C botulism in two organic, free-range commercial layer farms in the Midwest. Hens affected were 64-wk-old Hy-Line brown hens and 34-wk-old Hy-Line brown hens owned by the same company, but housed on different premises, with approximately 20,000 birds per house. Mortality over the 2 wk of investigation was estimated to be up to 8% and 2.8%, respectively, with birds acting listless, lethargic, and depressed. Clinical signs consisted of progressive paralysis, and severely affected birds were moribund and laterally recumbent. Hens had ruffled feathers that easily epilated, with loss of muscular tone in the neck, tail, and wings. Hens had closed eyes and were reluctant to move. There were no significant gross or histopathologic lesions. Intestinal samples were submitted to the University of Pennsylvania Botulism Diagnostic Laboratory for real-time PCR and were positive for Clostridium botulinum organisms containing the Type C neurotoxin gene. Speculations on the source of the botulinum toxins include poor mortality removal leading to cannibalism of decomposing carcasses, as well as birds on the farm having access to putrid carcasses in the compost pile from a hole in their outdoor access fence.
authors.affiliation: A Department of Comparative Pathobiology and Animal Disease Diagnostic Laboratory, Purdue University, 406 S. University Street, West Lafayette, IN 47907.|B Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 2503 Vet Med, 1600 S. 16th Street, Ames, IA 50011.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Sato
authors.affiliation: A Department of Comparative Pathobiology and Animal Disease Diagnostic Laboratory, Purdue University, 406 S. University Street, West Lafayette, IN 47907.
authors.forename: William L
authors.initials: WL
authors.lastname: Wigle
authors.affiliation: C Department of Clinical Studies, New Bolton Center, University of Pennsylvania School of Veterinary Medicine, 382 W. Street Road, Kennett Square, PA 19348.
authors.forename: Susan
authors.initials: S
authors.lastname: Gallagher
authors.affiliation: C Department of Clinical Studies, New Bolton Center, University of Pennsylvania School of Veterinary Medicine, 382 W. Street Road, Kennett Square, PA 19348.
authors.forename: Amy L
authors.initials: AL
authors.lastname: Johnson
authors.affiliation: C Department of Clinical Studies, New Bolton Center, University of Pennsylvania School of Veterinary Medicine, 382 W. Street Road, Kennett Square, PA 19348.
authors.forename: Raymond W
authors.initials: RW
authors.lastname: Sweeney
authors.affiliation: A Department of Comparative Pathobiology and Animal Disease Diagnostic Laboratory, Purdue University, 406 S. University Street, West Lafayette, IN 47907.
authors.forename: Patricia S
authors.initials: PS
authors.lastname: Wakenell
mesh_terms: D000818:Animals; D001906:Botulism / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D002645:Chickens; D003014:Clostridium botulinum / Q000235:genetics / Q000302:isolation & purification*; D004196:Disease Outbreaks / Q000662:veterinary*; D005260:Female; D007422:Intestines / Q000382:microbiology; D015146:Midwestern United States / Q000453:epidemiology; D011201:Poultry Diseases / Q000453:epidemiology* / Q000382:microbiology; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary
keywords: Clostridium botulinum type C; PCR; botulism; commercial layers