Diagnosis

A simple and cost-effective way to identify whether or not EP is of clinical significance in a herd is to carry out examination of the lungs of a batch of pigs at slaughter.

Assessment of how many pigs had lung lesions (frequency) and the percentage of pulmonary tissue affected (severity) can provide a clear view as to the economic significance of the disease in the herd.

A more precise diagnosis is possible by the use of an ELISA assay or F.A.Test carried out on blood samples and which identifies the presence of the specific M hyo. antibody. Antibodies can be isolated approximately three to four weeks after infection arises although care should be taken since it is not possible to differentiate between vaccine induced antibodies and those arising as a result of naturally occurring infection.

M hyo can be detected very early in the infection process by means of the PCR testing (polymerase chain reaction) of nasal swabs from infected pigs. The presence of any pathogens on the nasal mucosa cannot, however, be automatically equated with the presence of an infection. An infection is only present if the animal develops clinical symptoms (cough, lung lesions) leading to the development of antibodies. Detection of the organism in the nasal passages may not necessarily mean that an infection has been established and disease is present in the herd. Under normal housing conditions the immune system of a healthy animal can deal with individual pathogenic organisms.