I hadn't heard of that but i know they only want "pure breed" perfect cats in their programs. Zoos used to sell over stocked animals to private keepers but it's not considered politicly correct to do so any more so I could see it being possible but I'll need to look and see if there's any articles on that. I mean that stuff is all made public through the freedom of information act so groups can get a hold of their records from USDA so if they were euthanizing just because there was no other zoo to take them and still breeding that would be big news so I'm a bit doubtful right now. They make a big stink about every death at a zoo natural causes or not.