I have had 3 Dogue de Bordeaux aka French Mastiff...
the largest weighing in at 200 lbs..they were the best dogs I ever had..the largest “Weatherby” would sit out on the front lawn with my daughter and her friends while they played and would not let any one near them..he was their protector...unfortunately he died of bloat, something I never heard of before until then

I have read that with dogs and bloat its usually because of the way they gobble down their food....better to give multiple small feeding....but with dogs, its what I have heard and not from experience...