Are you sure she never just said bloat? if it was bloat it happens in deep chested dogs, their stomach swells up and the gut can twist, boxers can get it also, so dont exercise him until an hour after feeding or an hour before exercise. Also restrict how much he drinks before a feed and after then give him free access. I also read on a website that you shouldn't feed a dry food with alfalpha in as this can cause bloat. My brain is like a civ, but i think the stomach swells with gas and the intestines close up not allowing the gas or food through, which can cause the dog to die if the syptoms aren't spotted straight away. If you put bloat in google alot of helpful info comes up on how to spot bloat and how to prevent it.
I hope this helps you abit, others will offer you more indepth info.
Warm Regards Susan