@Align  
No, the cows on the show are sapient.

So does that mean that the cows might be… used for the same purposes for the ponies as for us?  
Of course they wouldn’t show such a thing in the show, but is there nothing hindering headcanon from this sinister background process?  
…Or perhaps not so sinister. Considering the restaurant at the end of the universe…

Do we seriously have to go over the difference between animal and plant cells here?

Aren’t herbivores essentially eating the ‘meat’ of a plant anyhow?

Fourth option: Meat grows on plants in Equestria.

Third option: The meat is tofu.

Eating her wings

“Oh crap, this has meat in it. Eh, I doubt it was anyone I knew. [Munch munch]”

You can feed a horse on meat. Early arctic explorers used meat to feed their horses back before they realized sled dogs made better transportation in the snow.

worst thing they might get is the runs i think (if they ate a lot)

BP DOES have somethin there.

@tarin  
No it isn’t.
 
Horses are actually what you’d call opportunistic omnivores.  
They don’t hunt of course, but if they manage to kill a would be predator, or come across a fresh corpse, they have no problem eating it.
 
Many MANY horse owners even claim their horses will try to go for their (the humans) food, and if they make the mistake of leaving their lunch unguarded where the animal can reach it, it’s not gonna be there long.
 
Basically, it’s like a special treat that they’ll snag when they can before they go back to the hay.

Meat is toxic to horses  
Fluttershy is on the road to either a stomach pump or a slow, painful death

Yup.

Nope.