Studies of the role of Dermacentor occidentalis in the transmission of bovine chlamydial abortion.

Dermacentor occidentalis nymphal ticks were successfully infected with the agent of bovine chlamydial abortion. Multiplication of the agent was shown to occur during nymphal engorgement, but chlamydial isolations were not made from nymphal ticks after detachment or during subsequent metamorphosis. Primary tissue cultures of nymphal viscera infected in vitro or in vivo failed to demonstrate chlamydial replication.