The canine transplantable venereal tumor is a naturally occurring transplantable round-cell tumor in dogs. Although experimental transplantable tumor models in rodents and rabbits are readily available, a reliable transplantable tumor model in a large animal that more closely resembles the physical dimensions of humans has not been available. A tumor model in a large animal would have a wide range of biomedical research applications, including the study of various interventional imaging techniques. In this report, we characterize the experimental transplantation of the canine transmissible venereal tumor in the brain, skin, muscle, prostate, lung, liver, and bone of dogs and provide X-ray computed tomographic and magnetic resonance imaging characteristics of the tumors in the brain, muscle, lung, and prostate.