Transmissible venereal tumor (TVT) is a common disease occurring in the dog,
especially in countries where the population of stray dogs is high. Vincristine appears to
be an excellent mode of therapy and the treatment of choice (6). However, vincristine,
among other chemotherapeutic drugs, affects fertility in humans (4, 12, 13) and
possibly the dog (6). In the present study we have investigated the direct effects of
vincristine on several semen parameters in dogs with TVT.