Characterization ofMycoplasma suipneumoniae: a mycoplasma causing enzootic pneumonia of pigs

A micro-organism, previously known as the J agent, was grown on solid medium: its various characteristics suggested that it was a mycoplasma and it was provisionally namedMycoplasma suipneumoniae. In the growth-inhibition and metabolic-inhibition tests,M. suipneumoniaewas indistinguishable fromM. hyopneumoniae(Maré & Switzer, 1965). By the growth-inhibition test,M. suipneumoniaeseemed unrelated to all of a wide range (42 strains) of other mycoplasmas examined. These results suggest that, if the similarity betweenM. suipneumoniaeandM. hyopneumoniaeis substantiated in further work, these latter two strains are probably a new species. M. suipneumoniaewas also identified by the metabolic-inhibition test, by precipitation in agar gel, and by immune-fluorescence. Using the last two methods,M. suipneumoniaewas distinguished from a second porcine mycoplasma (strain 603). The most important property ofM. suipneumoniaeis its ability to induce enzootic pneumonia experimentally in pigs.