What happens when an herbivorous animal attempts to eat meat?

Question

I was wondering particularly about equines.

Answer 1

Have you ever heard of MAD COW DISEASE? I can't
remember the correct disease terminology. this same
disease will effect horses, deer,moose,elk,and all
herbivores. Any animal that chews its cud cannot digest
or tolerate animal protein. Our cows are still being fed
feed with protein pellets in it. Some of the pellets include
dead cows.

Answer 2

Different set of digestive enzymes from carnivores. Probably have a hard time digesting the meat.

Answer 3

I know that, in history, warriors would train their war horses to eat flesh and it made them very mean. They would crave it, after it had been introduced to them.
This would help in combat because if you killed or wounded the man, the horse would still fight.
If you are concerned because your horse ate a mouse or something, I wouldn't worry.

Answer 4

whilst there are OCCAISIONAL reports of things like this (horses killing and eating chickens for example), their digestive system may not take full advantage of the nutrition meat can provide

Answer 5

They don't attempt at all. It's instinct for them not to. If they smell meat, they will not eat it. If they ever actually did, I don't think it would harm them.