title: Association of Beta2-Positive Clostridium perfringens Type A With Focal Duodenal Necrosis in Egg-Laying Chickens in the United States.
abstract: Focal duodenal necrosis (FDN) is a poorly understood intestinal disease of egg layers, and has been associated with drops in egg production and decreased egg weights. The etiology of this disease is still unknown, but the condition has been associated with Clostridium colinum and Clostridium perfringens. In order to investigate the etiology, duodenal samples were taken from hens with FDN. The hens originated from table egg layer farms in three states. The samples were examined by histopathology, bacteriology, and immunohistochemistry. Macroscopically, all samples contained focal to multifocal, variably sized, reddened or brownish gray areas of mucosal erosion. Histopathology revealed mild to severe heterophilic and lymphoplasmacytic enteritis with loss of enterocytes at the villous tips, luminal fibrinonecrotic exudate, and variable numbers of Gram-positive and Gram-negative rod-shaped bacteria within the lesions in 16/30 samples. Clostridium perfringens was isolated by anaerobic bacteriology from 4/13 samples that had characteristic microscopic lesions of FDN. Polymerase chain reaction (PCR) revealed that all four isolates were Type A C. perfringens, positive for beta2 gene and negative for necrotic enteritis toxin B and enterotoxin genes. PCR for Clostridium colinum applied to DNA extracted from frozen intestinal samples yielded negative results in 14/14 duodenal samples. Immunohistochemistry (IHC) for 7C. perfringens, alpha and beta2 toxins stained a few to numerous long rod-shaped bacteria present in the lesions. IHC for alpha and beta2 toxins also stained enterocytes at the villous tips, inflammatory cells in the lamina propria, as well as degenerated and sloughed enterocytes present within the luminal exudate. These findings suggest that C. perfringens may play a role in the development of FDN. Experimental challenge studies with these isolates still need to be performed in order to reproduce the disease and fulfill Koch's postulates.
authors.affiliation: A Poultry Diagnostic and Research Center, Department of Population Health, The University of Georgia, Athens, GA 30602.
authors.forename: M
authors.initials: M
authors.lastname: França
authors.affiliation: B Department of Poultry Science, The University of Georgia, Athens, GA 30602.
authors.forename: M A
authors.initials: MA
authors.lastname: Barrios
authors.affiliation: A Poultry Diagnostic and Research Center, Department of Population Health, The University of Georgia, Athens, GA 30602.
authors.forename: L
authors.initials: L
authors.lastname: Stabler
authors.affiliation: C Avian Health International LLC, Flowery Branch, GA 30542.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Zavala
authors.affiliation: D California Animal Health and Food Safety Laboratory System, University of California, Davis, Tulare, CA 93274.
authors.forename: H L
authors.initials: HL
authors.lastname: Shivaprasad
authors.affiliation: A Poultry Diagnostic and Research Center, Department of Population Health, The University of Georgia, Athens, GA 30602.
authors.forename: M D
authors.initials: MD
authors.lastname: Lee
authors.affiliation: A Poultry Diagnostic and Research Center, Department of Population Health, The University of Georgia, Athens, GA 30602.
authors.forename: A M
authors.initials: AM
authors.lastname: Villegas
authors.affiliation: E California Animal Health and Food Safety Laboratory System, University of California, Davis, San Bernardino, CA 92408.
authors.forename: Francisco A
authors.initials: FA
authors.lastname: Uzal
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism; D002645:Chickens; D003015:Clostridium Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D003016:Clostridium perfringens / Q000235:genetics*; D004386:Duodenum / Q000382:microbiology / Q000473:pathology; D005260:Female; D007410:Intestinal Diseases / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D009336:Necrosis / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D011201:Poultry Diseases / Q000382:microbiology / Q000473:pathology*; D010738:Type C Phospholipases / Q000235:genetics / Q000378:metabolism; D014481:United States
chemical_list: D001427:Bacterial Toxins; D002135:Calcium-Binding Proteins; C109896:cpb2 protein, Clostridium perfringens; D010738:Type C Phospholipases; C040649:alpha toxin, Clostridium perfringens
keywords: Clostridium perfringens; focal duodenal necrosis; laying chickens