It is a mix martin, horses are bred as cattle in the likes of Poland. They have specific breeds of horse that are thick set and never handled by people other than for transport/slaughter. Also any animal who has come to the end of his useful life can be slaughter for human consumption as long as the passport has a declared the carcass free from drugs (or whatever you know what I mean I am sure)
Regarding the European Horsemeat trade, horses by their very design are far from easy to kill, tall animals, with long necks and nervous dispositions. Many of the "farmed" horses will feel much stressed by lack of personal space when transported without separate partitions, and their vulnerable limbs are at high risk of damage. Horses are delicate animals, both in body and mind - its a low welfare meat that is for sure.
The polish meat horses I have dealt with first hand, as we used to buy them to turn them into ridden horses.
Anyone who condones the horsemeat trade ought first to try and catch, restrain and pat an unhandled colt on its head... a challenge for any horseman, let alone a busy slaughter man.
There are lots of surplus horses around in the Uk & Ireland at the moment, that’s a different story, and using them to feed a nation when we have ample supply of sheep/cattle is a bit of an extreme answer!
Traditionally in this country those horses who have served their owners as mounts have feed our dogs, and the feet made glue, thats all good wi me, just wish they didn’t also throw cats n dogs into the dog food too!!!