Mycoplasma gallisepticum and Mycoplasma synoviae

Test codes:

B0032 - Qualitative detection of Mycoplasma gallisepticum by polymerase chain reaction. B0032 is included in the poultry respiratory panel.

B0033 - Qualitative detection of Mycoplasma synoviae by polymerase chain reaction

P0012 - Mycoplasma poultry panel: Qualitative detection and differentiation of M. gallisepticum and M. synoviae by polymerase chain reaction

Mycoplasma synoviae is a known pathogen associated with the development of synovitis and chronic respiratory disease in chickens and turkeys. Clinical symptoms include joint swelling, coryza and respiratory rales. Economic losses due to M. synoviae infection include reduced egg production, lowered hatchability of chicks and downgraded meat quality. However, there may be no symptoms developed in birds infected with this bacterium.

On the other hand, Mycoplasma gallisepticum is associated with chronic respiratory disease in chickens and infectious sinusitis in turkeys. The symptoms generally seen are coryza, coughing, nasal exudate and respiratory rales. Economic losses due to M. gallisepticum infection include reduced egg production, lowered hatchability of chicks and downgraded meat quality.

Infection rates may be very high and once an infection starts, it can spread rapidly within and between houses on a farm. Infected poultry can have variable symptoms but the mortality rate is generally less than 10%. Infection takes place through the conjunctiva or upper respiratory tract with a long incubation period, 11–21 days following contact exposure. Transmission can be transovarian, or lateral via respiratory aerosols and direct contact. Although the survival of the infectious agent outside the bird is poor, it can be transmitted on fomites. Predisposing factors include stress and viral respiratory infections.

Infection with these mycoplasmas must be differentiated from viral arthritis, staphylococcal arthritis, Ornithobacterium rhinotracheale and viral respiratory disease with colibacillosis. M. gallisepticum and M. synoviae are very similar antigenically, so these two bacteria can be very difficult to differentiate by conventional serological tests (Bradbury and Jordan, 1971, 1973). Molecular detection using PCR is especially useful, as the primers used in the assay are designed over a highly conserved region that differentiates the two bacteria. PCR is much more sensitive and specific than other conventional methods to detect these bacteria.

Utilities:

• Confirm the disease causing agent
• Shorten the time required to confirm clinical diagnosis and differentiation of M. gallisepticum or M. synoviae infection
• Ensure that flocks are free of mycoplasmas
• Early prevention of spread of mycoplasmas among and between flocks
• Minimize human exposure to mycoplasmas
• Safety monitoring of biological products and vaccines that derive from birds

References:
Bradbury, J. M. and Jordan, F.T.W. (1971) The adsorption of gamma globulins to Mycoplasma gallisepticum and the possible role in nonspecific serological reactions. Vet. Rec. 89:318.
Bradbury, J. M., and Jordan, F.T.W. (1973) Nonspecific agglutination of Mycoplasma gallisepticum. Vet. Rec. 92:591-592.

Preferred specimen: Tracheal swab, shipped overnight at room temperature.

For specimen types other than those listed here, please call to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodology: Qualitative PCR

Normal range: Nondetected