Publications des agents du Cirad

Cirad

Contagious caprine pleuropneumonia

Thiaucourt F.. 2012. In : Manual of diagnostic tests and vaccines for terrestrial animals : (mammals, birds and bees). Paris : OIE, p. 995-1007.

Contagious caprine pleuropneumonia ( CCPP) is a severe disease of goats caused by Mycoplasma capricolum subspecies capripneumoniae (Mccp). This organism is closely related to three other mycoplasmas: M . mycoides subsp. mycoides large colonies (LC), M. mycoides subsp. capri, and M. capricolum subsp. capricolum. Unlike true CCPP, which is confined to the thoracic cavity, the disease caused by the latter three mycoplasmas is accompanied by prominent lesions in other organs and/or parts of the body besides the thoracic cavity. Typical cases of CCPP are characterised by extreme fever (41-43°C), high morbidity and mortality rates in susceptible herds affecting all ages and both sexes, and abortions in pregnant goats. lt appears to be transmitted by an infective aerosol. After approximately 2-3 days of high fever, respiratory signs become apparent: respiration is accelerated and painful, and in some cases is accompanied by a grunt. Coughing is frequent, violent and productive. In the terminal stages, animals are unable to move - they stand with their front legs wide apart, the neck is stiff and extended, and sometimes saliva continuously drips from the mouth. Post-mortem examination reveals fibrinous pleuropneumonia with massive lung hepatisation and pleurisy, accompanied by accumulation of straw-coloured pleural fluid. The disease has been shown recently to affect wild ruminants such as the wild goats (Capra aegagru), Nubian Ibex (Capra ibex Nubian) and Laristan Mouflon (Ovis orientalis laristanica) and Gerenuk (Litocranius walleri). Clinical disease and seropositivity have been reported in sheep in contact with affected goats, but the role of sheep as reservoirs of infection is unclear. Identification of the agent: Definitive diagnosis requires culture of the causative organism from lung tissue samples and/or pleural fluid taken at post-mortem. After cloning and purification, isolates can be identified by several biochemical, immunological and molecular tests. Isolating the causative agent is a difficult task. Recently polymerase chain reaction based tests have been described and shown to be specific, sensitive and can be applied directly to clinical material, such as lung and pleural fluid. Serological tests: Serological tests have been applied for the diagnosis of CCPP in outbreaks in Eritrea and Turkey. Such tests are best used on a herd basis rather than for diagnosis in individual animals. The complement fixation test remains the most widely used serological test for CCPP, although the latex agglutination test is being increasingly used in the diagnostic laboratories as well as a pen side test; it can used to test whole blood as well as serum. Indirect hemagglutination is also used. A specific competitive enzyme-linked immunosorbent assay has been developed, but is not widely available. As with the other serological tests, it does not detect all reactors, but its specificity and suitability for large-scale testing make it an appropriate test for epidemiological investigations. Requirements for vaccines and diagnostic biologicals: Vaccine against CCPP caused by Mccp is available commercially. (Résumé d'auteur)

Mots-clés : Épidémiologie; immunologie; vaccin; technique analytique; technique immunologique; test biologique; diagnostic; identification; ruminant; mycoplasma mycoides; mycoplasma capricolum; pleuropneumonie contagieuse de la chèvre; production de vaccin

Thématique : Maladies des animaux

Documents associés

Chapitre d'ouvrage

Agents Cirad, auteurs de cette publication :