title: Isolation of Actinobacillus pleuropneumoniae from layer hens showing clinical signs of infectious coryza.
abstract: Actinobacillus pleuropneumoniae is the causal agent of porcine pleuropneumonia, which is a highly contagious respiratory disease that affects swine nearly exclusively. An isolate with characteristics of some Pasteurellaceae family members (Gram-negative bacterium, pleomorphic, and NAD-dependent) was isolated from layer hens showing clinical signs of infectious coryza. This bacterium presented hemolysis on rabbit red blood cell agar plates, and PCR amplification and sequencing of its 16S rDNA gene indicated 99% identity with A. pleuropneumoniae serotypes 3 and 7. The presence of a putative apxIIA gene was also determined by PCR. A single, smooth colony of this bacterium inoculated in five, 7-day-old chicken embryos via the yolk sac route induced 100% mortality. However, inoculation into 10-wk-old, specific-pathogen-free chickens induced only light facial swelling, and reisolation of the inoculated bacterium was negative.
authors.forename: V M
authors.initials: VM
authors.lastname: Pérez Márquez
authors.forename: J López
authors.initials: JL
authors.lastname: Ochoa
authors.forename: C Vázquez
authors.initials: CV
authors.lastname: Cruz
authors.forename: P Sánchez
authors.initials: PS
authors.lastname: Alonso
authors.forename: G
authors.initials: G
authors.lastname: Olmedo-Alvarez
authors.forename: S
authors.initials: S
authors.lastname: Vaca
authors.forename: E Negrete
authors.initials: EN
authors.lastname: Abascal
mesh_terms: D000189:Actinobacillus Infections / Q000382:microbiology / Q000662:veterinary*; D016977:Actinobacillus pleuropneumoniae / Q000235:genetics / Q000302:isolation & purification*; D000818:Animals; D002645:Chickens; D005260:Female; D010802:Phylogeny; D011201:Poultry Diseases / Q000382:microbiology*; D013047:Specific Pathogen-Free Organisms