title: Proliferative Enteropathy caused by Lawsonia intracellularis in Chickens.
abstract: Proliferative enteropathy (PE) is an infectious disease caused by Lawsonia intracellularis (Li), an obligate intracellular bacterium. PE is endemic in swine herds and has been reported in a variety of mammals including horses, hamsters, rabbits, rats, guinea pigs, ferrets, foxes, dogs, sheep, deer and non-human primates. Avian cases are reported only in ratite birds, including emus and ostriches. Some studies show an absence of Lawsonia spp. infection in chickens. In this study, we performed morphological and bacteriological examinations on the intestines of two broiler chickens that had been condemned at a poultry slaughter plant in Japan due to intestinal haemorrhage, which was a result of focal coccidial enteritis. Histopathology revealed proliferation of the villous epithelium in the small and/or large intestines, especially the caeca, regardless of coccidial lesions. Warthin-Starry silver staining and immunohistochemistry using anti-Li monoclonal antibody revealed numerous bacteria and/or antigens in the villous epithelium. Scanning electron microscopy and transmission electron microscopy revealed the presence of curved rods, morphologically compatible with Li, in the apical cytoplasm of the epithelium. Polymerase chain reaction products specific for Li were amplified from DNA samples extracted from formalin-fixed and paraffin wax-embedded tissue. These results suggest that Li can cause PE, characterized by proliferation of the villous epithelium, in chickens.
authors.affiliation: Hyogo Prefectural Meat Inspection Centre, Kakogawa, Hyogo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ohta
authors.affiliation: National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kimura
authors.affiliation: National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Katsuda
authors.affiliation: National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kobayashi
authors.affiliation: National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
authors.forename: O
authors.initials: O
authors.lastname: Mikami
authors.affiliation: National Institute of Animal Health, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan. Electronic address: haritani.makoto@mail.u-tokyo.ac.jp.
authors.forename: M
authors.initials: M
authors.lastname: Haritani
authors.affiliation: Research Centre for Food Safety, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Onodera
mesh_terms: D000818:Animals; D002645:Chickens / Q000382:microbiology*; D045824:Desulfovibrionaceae Infections / Q000662:veterinary*; D004751:Enteritis / Q000662:veterinary*; D007150:Immunohistochemistry; D020639:Lawsonia Bacteria; D008854:Microscopy, Electron; D016133:Polymerase Chain Reaction; D011201:Poultry Diseases / Q000473:pathology*
keywords: Lawsonia intracellularis; chicken; proliferative enteropathy