
the serological differentiation of mycoplasma strains (pleuro-
pneumonia-like organisms) from various sources
a complement fixation test with rabbit antisera was used to differentiate 82
cultures of mycoplasma from man, mammalian cell cultures, laboratory rats and
mice, cattle, goats, poultry, embryonated eggs and sewage.
seventeen serotypes were distinguished, 5 from man, 1 from mammalian cell
cultures, 4 from rats and mice, 4 from cattle and goats, 2 from poultry and one
saprophytic.  most of these corresponded to recognized species of mycoplasma,
but 1 of human origin (represented by 1 strain, navel), and 1 from tissue
cultures (5 strains), may represent new species.  r38, one of the serotypes
from rats, could be distinguished from the species m. arthritidis, but is
probably an antigenic variant rather than a distinct species.  two species
hitherto recognized as distinct m. arthritidis and m. hominis type 2, could not
be distinguished and appear to constitute a single species.  these findings
illustrate the necessity, from the viewpoint of taxonomy, of comparing
mycoplasma strains by serological methods.
the serotypes of human and animal origin were largely host-specific.
exceptions were the inclusion of m. arthritidis from rats and m. hominis type 2
from man in a single serotype, the finding of a bovine organism among the
strains isolated from goats and of a saprophytic strain in a rat.
in relation to the aetiology of disease in man and animals, the isolation of
an endogenous mycoplasma from embryonated eggs used to passage infective
material illustrates the importance of identifying these organisms
serologically.  the demonstration of mixed mycoplasma infections in lesions
in two rats shows the necessity of adequately purifying all cultures of
mycoplasma before examination.
