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Fly-Biting Behavior in Dogs

Most fly-biting behavior has a medical cause.

Fly-biting is a behavior in which dogs appear to be watching something and then start snapping at the air as though they are trying to catch a bug, even though there is nothing there.

This behavior can appear to be compulsive and may begin suddenly. It may also be intermittent.

What Causes Canine Fly-Biting Behavior?

This strange behavior can be caused by a neurological problem. An area of the brain may be experiencing abnormal activity, resulting in fly-biting. This is called a partial seizure, and it can be caused by trauma, toxins, brain tumors, infections, and metabolic disorders. You can learn more here: "Seizures in Dogs: An Overview."

Recent research is indicating that fly-biting behavior may also be caused by gastrointestinal issues. In a small study, seven dogs with fly-biting behavior had a host of tests done, and they were all found to have some type of gastrointestinal problem, including delayed stomach emptying and acid reflux. The fly-biting behavior improved with treatment of the GI problem.

Puppies may snap at the air as part of their play behavior, without a concurrent medical condition.

Diagnosis of Fly-Biting Behavior in Dogs

Diagnosing the cause of your dog's fly-biting behavior will involve evaluating the circumstances surrounding it, taking into account any other signs your dog may be concurrently exhibiting, and potentially running tests.

If you can record some episodes of your dog's fly-biting behavior, it may help your veterinarian hone in on the cause. For example, if your dog is extending his neck and lifting his head prior to snapping at the air, a GI cause may be more likely. If your puppy is snapping at the air as part of an exuberant play session, it may simply be canine "make believe." If your dog is circling or having muscle spasms before or after the behavior, it may be a partial seizure.

Works Cited

  1. Diane Frank, M. C.-B. (2012, Dec.). Prospective medical evaluation of 7 dogs presented with fly biting. Retrieved from NCBI.

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