A Serologic Variant of Mycoplasma Hyorhinis Recovered from the Conjunctiva of Swine

In an examination of conjunctival samples from 40 piglets for mycoplasmas, 17 isolates were obtained. Eight could be identified as Mycoplasma hyorhinis, three as Mycoplasma flocculare, and one as Acholenlasma sp. Five strains were not readily identifiable, but together with two previously recovered strains they were found to represent a distinct serogroup. All seven strains were glucose and phosphatase positive. Incubation in a CO₂-enriched atmosphere led to enhancement of the growth on solid medium. The serogroup was serologically related to M. hyorhinis, but not to a number of other glucose fermenting species of mycoplasma, and it may therefore be regarded as a new subspecies of M. hyorhinis.