We experienced vertical infections of puppies with Hepatozoon canis fr
om 1990 to 1992. In 23 of 29 (79.3%) puppies from a total of 6 deliver
ies, gamonts or meronts were detected from 16 to 60 days after birth.
The mother dogs were delivered of the puppies under tick-free conditio
ns treated with an acaricide. There was no chance of infection of the
puppies with H. canis after birth. Therefore, the vertical transmissio
n of H. canis was supposed to be established in the family of dog.