I have an almost 15 year old lab mix. Lately he has problems breathing off and on. Maybe once or twice a week it sounds like he is grasping for air or has something caught in his throat. It lasts anywhere from 30 seconds to sometimes a couple of minutes. My friend just told me this runs in labs. Her dog had it and the vet told her he was suffocating. She thought this was common. Have you heard of something like this?