A selected colony free from ocular infection with pleuropneumonia-like organisms of the conjunctival type was developed from young Princeton mice delivered by cesarean section and reared by uninfected Swiss foster mothers. Young mice from this colony continued to show sporadic ocular manifestations similar to those observed in infected mice. This reaction was non-inflammatory in nature.
The organisms previously recovered from the altered conjunctivae of Princeton mice were established on the conjunctivae of selected mice of the special colony both by direct contact and by the local implantation of ocular washings and concentrated cultures.
The factors associated with the conjunctival reaction in infected Princeton mice are discussed.