my golden retriever is like that. hoe starts running around the room, panting heavy and sometimes has seizures cuz of it. meanwhile my basset hound just lifts his head up, looks around and goes back to sleep.they already got anti-depressants n shyt for pets. i got a yellow lab and she damn near has a heart attack everytime there's thunder. The vet gave us Valium. I know thats an anti-anxiety drug, but you get my point...
In regards to the thread, the way i see it...if animals were capable of suicide it would indicate that they are capable of complex thought. I would imagine that ability would be observable in other actions as well.