title: Value of the clinical examination in diagnosing enzootic pneumonia in fattening pigs.
abstract: The diagnosis of enzootic pneumonia at the herd level should be based on a combination of different methods. Currently, clinical examination is usually considered to be a low value method, particularly compared to the direct detection of Mycoplasma hyopneumoniae in lung lesions by PCR. The present study compared the value of accurate clinical examination (including the quantitation of coughing), PCR on bronchoalveolar lavage fluid, and serological testing of blood samples for the purpose of diagnosing enzootic pneumonia. The coughing index (average % of pigs coughing per minute of observation) was determined in fattening pigs from 59 herds, and ranged from 0% to 6.7% with a median of 2.4%. Five hundred and ninety bronchiolar lavage samples and 1179 serum samples were taken from pigs in those 59 herds and tested for M. hyopneumoniae specific DNA and antibodies, respectively. In herds where ≥ 50% of lavage fluids were PCR positive, the likelihood of a higher coughing index was increased by 76% (OR: 1.76; 95% CI: 1.14-2.72) compared to herds with <50% of positive samples. For antibodies (determined by ELISA) a seroprevalence of ≥ 50% increased the likelihood of a high coughing index by 50% (OR: 1.50; 95% CI: 1.03-2.20). In 78.1% of all herds with a seroprevalence of ≥ 50% against M. hyopneumoniae, the PCR-prevalence and the coughing index were above the median (50% and 2.4%, respectively). It was concluded that in fattening pigs a quantitative assessment of the onset of coughing - typically dry and non-productive - improves the diagnosis of enzootic pneumonia and can occasionally substitute for the detection of M. hyopneumoniae by PCR.
authors.affiliation: Field Station for Epidemiology, University of Veterinary Medicine Hannover, Foundation, Buescheler Street 9, Bakum D-49456, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Nathues
authors.forename: Joachim
authors.initials: J
authors.lastname: Spergser
authors.forename: Renate
authors.initials: R
authors.lastname: Rosengarten
authors.forename: Lothar
authors.initials: L
authors.lastname: Kreienbrock
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Grosse Beilage
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology*; D003371:Cough / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D005858:Germany / Q000453:epidemiology; D045705:Mycoplasma hyopneumoniae / Q000276:immunology / Q000302:isolation & purification*; D045729:Pneumonia of Swine, Mycoplasmal / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology / Q000382:microbiology; D016133:Polymerase Chain Reaction / Q000662:veterinary; D016036:Seroepidemiologic Studies; D013552:Swine
chemical_list: D000907:Antibodies, Bacterial