Submitted to: International Journal of Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/31/2008
Publication Date: 2/23/2009
Citation: Leigh, S.A., Evans, J.D. 2009. Detection of Mycoplasma gallinarum by real-time PCR. International Journal of Poultry Science 8(2):108-111.
Interpretive Summary: Mycoplasma gallinarum has the potential to serve as a cofactor in causing avian respiratory disease during mixed infections with respiratory viruses and their vaccine strains. Little research has been performed using M. gallinarum, including methods of detecting M. gallinarum infection. Real-time PCR conditions were developed from an existing 16S rDNA primer set for rapid detection of M. gallinarum carrier status. A second primer set was also developed that provides a rapid means of strain differentiation based on real-time PCR analysis. These tools will enhance our ability to study the pathogenic potential of M. gallinarum as well as track it’s presence in commercial flocks.
Technical Abstract: Mycoplasma gallinarum colonizes poultry as well as mammals, but is considered to have a commensal relationship with its hosts. Though unable to cause poultry disease by itself, reports have been published suggesting a synergism during mixed infections between M. gallinarum and respiratory viruses or their vaccine strains that can precipitate airsacculitis. Currently, little research is being done on M. gallinarum and little is known about its carrier rate in chickens and other poultry. Two primer sets were tested for their ability to detect M. gallinarum using real-time PCR. One set published by Lauerman amplifies a fragment from the M. gallinarum 16S ribosomal DNA sequence. The other set (101-2) was developed in this laboratory and amplifies a short segment of DNA that appears to be unique to some strains of M. gallinarum. The Lauerman primer set is specific for M gallinarum and has a detection limit of 100 genomes. The 101-2 primer set is specific for some strains of M. gallinarum, although it is 100-fold less sensitive than the Lauerman primer set. The 101-2 primer set appears to be unsuited for M. gallinarum detection, but it does provide a method of differentiating M. gallinarum strains by PCR. These primer sets provide a means to rapidly determine the M. gallinarum carrier status of flocks by real-time PCR, and will help in identifying M. gallinarum in mixed infections.