title: Prevalence of amyloid deposition in mature healthy chickens in the flock that previously had outbreaks of vaccine-associated amyloidosis.
abstract: Avian amyloid A (AA) amyloidosis is commonly observed in adult birds with chronic inflammation, such as that caused by bacterial infection. We previously described vaccine-associated AA amyloidosis in juvenile chickens. In this study, the prevalence of amyloid deposition was measured in mature healthy chickens that survived a previous outbreak of avian AA amyloidosis while they were juveniles. Herein, we analyzed the amyloid deposition in mature chickens and compared the prevalence of amyloid deposition with juvenile chickens obtained in our previous study (Murakami et al., 2013). We found that: 1) amyloid deposition in the liver was absent in mature chickens, while juvenile chickens had a rate of 24%; 2) amyloid deposition in the spleen was observed in 36% of juvenile chickens and in 40% of mature chickens; 3) amyloid deposition in the pectoral muscle of mature chickens (43.75%) was approximately half that of juvenile chickens (88%). These results suggest that additional amyloid deposition in chickens previously exposed to AA amyloidosis may not worsen with age. Further, amyloid deposition in chickens may tend to regress when causative factors, such as vaccinations and/or chronic inflammation, are absent.
authors.affiliation: Laboratory of Veterinary Microbiology, Department of Veterinary Medicine, Gifu University, 1-1 Yanagido, Gifu-shi, Gifu 501-1193, Japan.
authors.forename: Kanata
authors.initials: K
authors.lastname: Ibi
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Murakami
authors.forename: Wael Mohamed
authors.initials: WM
authors.lastname: Goda
authors.forename: Naoki
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Naotaka
authors.initials: N
authors.lastname: Ishiguro
authors.forename: Tokuma
authors.initials: T
authors.lastname: Yanai
mesh_terms: D000375:Aging; D000682:Amyloid / Q000378:metabolism*; D000686:Amyloidosis / Q000139:chemically induced / Q000662:veterinary*; D000818:Animals; D056486:Chemical and Drug Induced Liver Injury / Q000473:pathology / Q000662:veterinary*; D002645:Chickens; D004196:Disease Outbreaks / Q000662:veterinary*; D008099:Liver / Q000378:metabolism / Q000473:pathology; D018482:Muscle, Skeletal / Q000378:metabolism / Q000473:pathology; D011201:Poultry Diseases / Q000139:chemically induced / Q000473:pathology*; D013154:Spleen / Q000378:metabolism / Q000473:pathology; D014018:Tissue Distribution; D014612:Vaccines / Q000009:adverse effects*
chemical_list: D000682:Amyloid; D014612:Vaccines