Mycoplasma bovis

Mycoplasma bovis

Refer to MPI guidelines for commercial testing of M. bovis

Species: Bovine

Specimen: Milk/colostrum; nasopharyngeal swabs, tonsillar crypt swabs, preputial swabs; Semen; Exudates/dry swabs of lesions.

Container: Sterile container

Collection protocol: See guidelines published by Dairy Cattle veterinarians’ branch of the NZVA and by MPI – – Nasopharyngeal swabs / Preputial swabs

Special handling/shipping requirements: Samples are to be transported and stored chilled. Do not freeze samples.

General information about the disease: Mycoplasma bovis is a bacterium that causes illness in cattle, including udder infection (mastitis), abortion, pneumonia, and arthritis.  Mycoplasma bovis is the most common mycoplasma of cattle, and the most important of its family. The closest relative to M. bovis is M. agalactiae found in sheep.  M. bovis was first reported in New Zealand in 2017. The clinical symptoms of affected cattle in New Zealand so far includes: mastitis in dry and milking cows, arthritis in cows, late-term abortions and the birth of premature calves. It is expected that calves on affected farms will have an increased incidence of pneumonia and otitis media. This will increase the morbidity and mortality on affected farms and if this disease establishes, an increased replacement rate for cattle will be required.  The organism has not been detected in New Zealand prior to 2017 despite serious attempts to find it via surveillance. A 2009 survey of bulk milk (vat) samples randomly selected from New Zealand dairy farms found no evidence of infection using polymerase chain reaction (PCR) and bacterial culture techniques. M. bovis is listed as an Unwanted Organism under the Biosecurity Act 1993.

Comparison with other related tests:  The serum ELISA is one of the most sensitive tests for M. bovis but is unsuitable for use in single animals and small mobs and has the potential to produce false positive (possibly due to cross reaction with other species of mycoplasma) and false negatives in animals that have not seroconverted at the time of testing. It is good at detecting historic exposure and as herd test.