There are a variety of issues that can lead to a seizure. Thyroid problems, diabetes, sometimes the use of a chemical etc., or it can just happen due to hereditary issues. Liver or kidney problems can trigger issues too.
This site really covers seizures well
www.canine-epilepsy-guardian-angels.com
It goes over things that cause seizures and things that look like seizures that aren't.
You should have your vet check her out.
They can do bloodwork and check for a variety of health issues.
They may want you to wait and see if it happens again before doing any testing. Some dogs will have one odd episode and then never have another one again.
Do go through the above site so you will have a good understanding of the potential issues which will let you talk intelligently to your vet about this.
Hope this helps you!
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