About Seizures in Boxer Dogs

Two different forms of epilepsy exist in dogs. The first form is “primary epilepsy,” which is also known as inherited or “true” epilepsy. However, this kind of epilepsy can only be identified by ruling out all other sources of epilepsy. The boxer is one of several breeds that have a genetic predisposition, although the genetic source has not been identified. Secondary epilepsy is epilepsy that has a readily identifiable cause, often from sources outside the dog’s body. If a dog begins having seizures between 1 and 3 years old, then a genetic source of seizure activity is considered. Seizures that occur when a dog is 4 years or older are typically considered to be from a secondary source.

Seizures are the primary symptom associated with brain tumors. Boxers are brachycephalic dogs; that is, they have rounded skulls and pushed-in faces. These characteristics increase the breed’s risk of brain tumors associated with the pituitary gland and for gliomas, tumors that start in the “glial” or supporting cells of the brain. Gliomas can range from benign to malignant, but all can interfere with the brain’s functions. In addition to seizures, brain tumors can cause behavioral changes, circling, head tilting and unsteadiness while walking, among other symptoms, depending on the location of the tumor. A biopsy or an X-ray must be performed to affirm the presence of a tumor, which can be treated by surgical removal or by treating symptoms prior to radiation or chemotherapy. Gliomas, such as are common in the boxer, are frequently difficult to remove or may be inoperable. Continuing research is being conducted at the Department of Neurology at North Carolina State University in an attempt to discover mutations and conditions that predispose the boxer and other breeds to brain tumors.

Current research indicates that boxers may be genetically predisposed to degenerative myelopathy. The diseases covered by this medical term have a gradual, progressive effect on the canine central nervous system. The dog’s spinal cord and brain stem neurons fail to send the correct messages to the muscles and limbs. This degeneration causes the dog to experience tremors that can be mistaken for petit mal seizures, the inability to control elimination of waste and paralysis, among other symptoms.

Boxers are more prone to idiopathic seizures -- seizures of unknown origin -- than other breeds. In addition to the causes of seizures in boxers listed above, boxers may also experience seizures caused by head injuries, by loud or repeated noises that trigger seizure activity, and by parasites. Although researchers have not identified the genetic marker that would explain it, boxers also have a genetic predisposition to seizures in general. It is important to observe your boxer to determine what, if any, triggers exist that cause your dog to have a seizure, so you can reduce the probability of him experiencing one.