Mycoplasma hyopneumoniae typing based on the polyserine repeat motif of P146 for monitoring this pathogen before and after an eradication program

TAMIOZZO, P.J.; LUCCHESI, P. M. A.; AMBROGI, A.

JOURNAL OF SWINE HEALTH AND PRODUCTION

AMER ASSOC SWINE VETERINARIANS

Año: 2013 vol. 21 p. 309 - 312

1537-209X

Mycoplasma hyopneumoniae diversity was determined using a molecular typing method based on the polyserine repeat motif within the p146 gene. Three related Argentinian farms (A, B, and C) were investigated. To obtain a population free of enzootic pneumonia on Farm C, a partial depopulation program had been carried out first on Farm A and then on Farm B. Finally, Farm C was populated with early-weaned piglets from Farm B. To evaluate the success of the partial depopulation program, the farms were monitored for clinical signs and by serological testing, lung examination at slaughter, and nested polymerase chain reac­tion (nPCR). It was concluded that they were free of enzootic pneumonia, but M hyopneu­moniae remained despite the eradication mea­sures applied. An outbreak of enzootic pneu­monia in Farm C triggered an investigation of M hyopneumoniae genetic diversity in these farms. For this purpose, all DNA samples obtained from PCR-positive nasal swabs were further characterized using another nPCR designed for M hyopneumoniae typing. Several M hyopneumoniae types were identi­fied in these farms, but one strain seemed to be present before and after the application of the partial depopulation program. Unam­biguous discrimination of M hyopneumoniae would require analysis of other genomic regions.