An investigation into the viability of broth cultures of the T1 strain of Mycoplasma mycoides sub-species mycoides.

The T1 broth vaccine against contagious bovine pleuropneumonia can only be stored for four weeks at +4 degrees C because after that time the titre of Mycoplasma mycoides sub-species mycoides falls below the minimal vaccinating dose. An investigation into the death of these organisms during the stationary growth phase was made. The culture medium in which the vaccine was prepared was found to contain adequate nutrients. Control of the pH by the addition of KOH was shown to preserve the viability of the organism: there was no drop in titre during 336 h (14 days) at 37 degrees C. Use of this technique may prove valuable as a means of preserving the viability of T1 broth vaccine.