My name is ***** ***** I’ve been involved professionally with dogs in the health and behavioral fields for over 18 years. It will be my pleasure to work with you today.
Your dog may have experienced a seizure. Seizures in older dogs can be due to organ dysfunction such as kidney or liver failure. You can read about seizures and the different kinds here:
A dog may also "faint" in which they fall to the ground usually on their side, stare straight ahead and seem paralyzed which indicates a heart problem.. This is called syncopy and can be read about here:
I would have your dog seen by your vet as soon as possible and limit your dog's activity until she can be seen in case it is heart related and not seizure related. If you have a video camera, and this happens again, taping the behavior will help your vet determine the cause.
Your boy is quite elderly, so definitely have a senior checkup done as well to check for organ dysfunction.
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