Is it possible that he is having a seizure? Ours used to experience similar symptoms.
“Petit Mal Seizure (aka Absence Seizure): Depending on the authority quoted, petit mals are described as either very rare or usually unrecognized in animals. Signs are brief (seconds) duration of unconsciousness, loss of muscle tone, blank stare, and possibly upward rotation of eyes. According to one authority (Kay), the term petit mal is misused by veterinarians and should only be accorded to cases manifesting very specific clinical signs and EEG abnormalities.”
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