An in vitro study of the replication of Mycoplasma ovipneumoniae

Abstract

The growth of a New Zealand strain of M. ovipneumoniae in broth culture at 37°C was examined. In these conditions, the organism had a minimum division time of 1.7 hr and attained a maximum titre of about 2×10⁹ CFU/ml. Growth produced sufficient turbidity, particularly in shaking cultures, to allow this to be correlated with the viable count. The cultures died rapidly following the attainment of maximum titre.

Electron microscopic examination revealed a morphology typical of mycoplasmas, except that most organisms measured 400 to 700nm in diameter which is relatively large. The presence of dumb-bell-shaped forms, and the absence of filaments suggest that the organisms divide by binary fission.