It’s because horses that live as companion animals or work animals are not tracked individually from birth like cows are. They also get lots of meds during their lives that wouldn’t be allowed in meat animals like cows and pigs. The horses in question are being sold to slaughter when they’re too old to work or ride anymore, and none of them have the sort of history data that meat animals accumulate. In the U.S. horses don’t go into meat but some U.S. horses are sold to Mexico and the meat is shipped to Europe where there -is- a huge market for horsemeat. This is just the tip of the proverbial iceberg on this scandal.
Many horses in question are beautiful wild horses the BLM rounds up and sells to slaughter buyers from Mexico. Gorgeous animals, symbols of freedom. Eating one would be just like throwing another American Eagle on the barbie.
Many wild horses have been tamed....and used for pack animals, other user-friendly purposes. No excuse whatsoever for slaughtering and selling American icons as junk. No living being is junk.
That's not what I meant. What I meant was that, a modern major manufacturer is generally expected to keep logs (usually on computer) of what they use. So I would expect that, when they make a batch of meat raviolis, they would log that batch ABC123XYZ used meat from shipment 1735278 from supplier "George's Meat".
Thus, when horse meat is discovered in batch ABC123XYZ, they can look up the log, call up "George's Meat", and scream at them about that specific shipment, and point the police investigators at the supplier.
In these days, with easy-to-use bar code scanners and cheap compute power and cheap disk space, it's negligent to NOT log things.