Years ago my FIL had a black lab/Aussie cross that looked like a pure lab. He fed it everything left over from his meals. Fries, burgers, ice cream, jelly, etc. He constantly fed it chocolate with no acute affects. At 7 years old it weighed 116 lbs. Obese. One day he called me and said his dog couldn't get up. It was on his slick kitchen floor, spread-eagled. I think it suffocated due to its weight pressing down on that floor. Dude cried like a baby when I told him it was dead.
The spot in his back yard where I buried it stayed green for several years.