People who sell you meat and tell you it's beef when it has horse and pork in it should be thrown in jail. I don't mind eating pork but not when I paid for beef. And eating horse meat is barbaric in my opinion, on the same level as eating dogs.

I grew up eating raw ground beef sandwiches. We ate it all the time and it was good. Nobody in the family ever once got sick. And as an adult I frequently had Steak Tartare which is raw ground beef with a raw egg and some herbs on top. Never once got sick from that either.
I don't know if I'd be willing to eat either of those things nowadays though. The codes of integrity and simple human decency have changed dramatically since my younger days. And not for the better.

Jani, we got a letter from the school last year informing us they would be using hamburger made with pink slime, Have you noticed when making hamburgers or taco meat, the consistency is different ? yikes!
And think of this, much of our fresh produce comes from Mexico or South America now, who knows what kind of soil conditions they have.

Having worked at meat processing at the factory level it is unlikely for meat of different animals to be deliberately mixed without labeling it as so. Federal inspectors at the factory level would not allow it.
Once meat reaches the consumer market level is where meat could have the possibility of being deliberately mixed as inspectors are not on a full time basis at that level.
Meat processing is highly regulated in this country and no one best not violate rules of processing.

It doesn't matter to me because I don't eat any of it. The food and drug administration doesn't inspect everything everywhere. Who knows???