The whipworm, known scientifically as Trichuris trichiura, is a parasite that can be found in either cats or dogs. The most common way your pet can pick up this parasite is by eating something that has already been infested. However, it is possible to transmit from animal to animal without actually ingesting anything. The eggs are very durable and can survive in their environment for months or even years. They are also very adaptable and can live in food, water, soil, feces, or on animal flesh. Old and young dogs alike can pick up this parasite.