title: In vitro colonization of porcine trachea by Mycoplasma hyopneumoniae.
abstract: Porcine tracheae maintained in culture were used in order to study the colonization by Mycoplasma hyopneumoniae. Rings excised from tracheae of newborn piglets were infected with M hyopneumoniae strain BQ 14 and, after different incubation times, were examined by light and electron microscopy. Non-infected tracheal mucosae maintained a normal appearance for several days. Infected tracheal rings showed progressive colonization with concomitant progressive damage to the mucosal surface. Early on during the infection, few mycoplasmas occurred over a ciliated epithelium. As the infection progressed, there was gradual loss of cilia; mycoplasmas tended to form microcolonies and to accumulate over the remaining ciliated cells. Mycoplasmas, first seen at the apex of the cilia, were then seen deeper in the inter-ciliary space; some were even seen in contact with microvilli. In histological investigation, the final stage of the infection was characterized by a marked destruction of the epithelium with exfoliation of the epithelial cells. Infected mucosae showed typical damage caused by M hyopneumoniae, namely reduction of ciliary activity after 5 days, loss of cilia, and sloughing of ciliated cells. Our data indicate that porcine tracheal organ culture can be advantageously used to study colonization by M hyopneumoniae.
authors.affiliation: Université de Montréal, Faculté de Médecine Vétérinaire, Département de Pathologie et Microbiologie, St-Hyacinthe, Quebec, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Jacques
authors.forename: B
authors.initials: B
authors.lastname: Blanchard
authors.forename: B
authors.initials: B
authors.lastname: Foiry
authors.forename: C
authors.initials: C
authors.lastname: Girard
authors.forename: M
authors.initials: M
authors.lastname: Kobisch
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001422:Bacterial Adhesion; D002923:Cilia / Q000382:microbiology / Q000502:physiology; D046508:Culture Techniques; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D009174:Mycoplasma / Q000254:growth & development* / Q000648:ultrastructure; D013552:Swine; D014132:Trachea / Q000382:microbiology* / Q000648:ultrastructure