Jackson, you must have huge bales of hay! Or else your idea of a slice is bigger than mine. Anyway, whatever works for you. Any of my horses/ponies would eat a slice of hay in aprox 3/4 hr in nets, 1/2hr if it was loose on the floor.

As for the weight, my 15hh middleweight cob weighs 550kg now, will weigh aprox 580kg by the end of the summer and even then he won't be obese, just overweight, so I can see how a 15.2hh heavyweight could easily weigh over 600kg, esp if it's obese.

It's not colic I'm concerned about if there's no food left overnight, but the development of stomach ulcers. Horses are designed to digest food pretty much all the time and their stomachs produce acid all the time, which will eat away at whatever is in there, so if there's no food, that's the lining of the stomach. That's why I don't like to see them left without food for more than a few hours, which is what the vet would recommend too. x