title: Association of increased rate of condemnation of broiler carcasses due to hepatic abnormalities with immunosuppressive diseases in the broiler chicken industry in Saskatchewan.
abstract: The objective of this study was to identify the causative agents of hepatitis observed in broiler chickens at processing. Livers of chickens from 16 broiler farms in Saskatchewan with gross lesions of hepatitis were collected at processing. In addition to routine bacterial isolation and histopathological examination, serologic studies for infectious bursal disease virus (IBDV) and Chicken anaemia virus (CAV), calculation of the ratio of the weight of the bursa of Fabricius (BF) to body weight (BBW), and histopathological examination of the BF were done. Of the 264 livers with gross lesions, 83% had multifocal to coalescing necrotizing hepatitis, 16% had perihepatitis, and 1% had hemorrhages. No definitive causative microorganisms were isolated from the hepatic lesions; however, no significant bacterial isolations were made. Bursal atrophy, low BBW ratio, and high titer of antibody against IBDV each correlated with the rate of total condemnations (P = 0.0188, P = 0.0001, and P = 0.0073, respectively). Nucleotide sequencing of IBDV isolated from the BF identified the variant strains Delaware-E and 586. Condemnation because of hepatic lesions was correlated with titer of antibody against IBDV and BBW (P = 0.016 and P = 0.027). The results of this study demonstrate that hepatic lesions in Saskatchewan chickens are not currently caused by a primary bacterial pathogen but are associated with indicators of immunosuppression that is likely due to variant IBDV.
authors.affiliation: Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B4 (Amini, Zachar, Popowich, Goodhope, Gomis); Department of Animal and Poultry Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8 (Knezacek); Canadian Centre for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5 (Willson).
authors.forename: Keyvan
authors.initials: K
authors.lastname: Amini
authors.affiliation: Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B4 (Amini, Zachar, Popowich, Goodhope, Gomis); Department of Animal and Poultry Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8 (Knezacek); Canadian Centre for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5 (Willson).
authors.forename: Tara
authors.initials: T
authors.lastname: Zachar
authors.affiliation: Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B4 (Amini, Zachar, Popowich, Goodhope, Gomis); Department of Animal and Poultry Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8 (Knezacek); Canadian Centre for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5 (Willson).
authors.forename: Shelly
authors.initials: S
authors.lastname: Popowich
authors.affiliation: Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B4 (Amini, Zachar, Popowich, Goodhope, Gomis); Department of Animal and Poultry Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8 (Knezacek); Canadian Centre for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5 (Willson).
authors.forename: Tennille
authors.initials: T
authors.lastname: Knezacek
authors.affiliation: Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B4 (Amini, Zachar, Popowich, Goodhope, Gomis); Department of Animal and Poultry Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8 (Knezacek); Canadian Centre for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5 (Willson).
authors.forename: Bob
authors.initials: B
authors.lastname: Goodhope
authors.affiliation: Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B4 (Amini, Zachar, Popowich, Goodhope, Gomis); Department of Animal and Poultry Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8 (Knezacek); Canadian Centre for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5 (Willson).
authors.forename: Philip
authors.initials: P
authors.lastname: Willson
authors.affiliation: Department of Veterinary Pathology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B4 (Amini, Zachar, Popowich, Goodhope, Gomis); Department of Animal and Poultry Science, College of Agriculture and Bioresources, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8 (Knezacek); Canadian Centre for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5 (Willson).
authors.forename: Susantha
authors.initials: S
authors.lastname: Gomis
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001424:Bacterial Infections / Q000150:complications / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary; D018175:Birnaviridae Infections / Q000150:complications / Q000662:veterinary; D017727:Chicken anemia virus; D002645:Chickens; D018173:Circoviridae Infections / Q000150:complications / Q000662:veterinary; D006520:Hepatitis, Animal / Q000453:epidemiology / Q000209:etiology / Q000473:pathology*; D007243:Infectious bursal disease virus; D011201:Poultry Diseases / Q000453:epidemiology / Q000209:etiology / Q000473:pathology*; D012525:Saskatchewan / Q000453:epidemiology; D012698:Serologic Tests
chemical_list: D000914:Antibodies, Viral