Persimmon seeds are dangerous to your dog. While persimmon without seeds is considered healthy, others argue that it is entirely not safe for your dog. Consequently, it is advisable to contact your veterinarian before feeding your dog persimmons. According to studies, persimmons contain a chemical responsible for intestinal obstruction in dogs. The chemical causes gluey mass and reacts with stomach acid. Symptoms include pits and seeds in your dog’s stool.