correct me if i am wrong, becase i dont know the first thing about horses..... i thought i remembered seeing a report, or something like that, where they said, because he was such a high performance race horse, that there would be no chance that he (barabo) would ever be able to move like he did, so euthanizing him was better(even though it is a terrible act), because he would just keep injuring himself. from trying to run like he was able to at one point.
again i dont know the first thing about horses, so i could be way way off.