The "wet tail" disease of hamsters is caused by mature forms of the internal parasite belonging to the tapeworm family. This disease manifests itself as a loss of appetite, watery-jelly-like diarrhea, marked sadness and weakening of physical condition. The hamster stops washing, pet hair loses its shine, and the area around the anus is very stained. With a strong infestation of parasites, the hamster may die as a result of blockage of the intestines by tapeworms. The sick individual should be isolated immediately, and the cage and its equipment must be thoroughly disinfected - scald it with boiling water with the addition of soda, and burn the old bedding and nest, then carefully wash our hands. Treatment is based on the administration of pharmacological agents. It is also effective to feed a few dried pumpkin seeds a day, a little castor oil in the evening, which will facilitate the removal of parasites from the body. After the hamster recovers, it should not be allowed to breed.