That's an interesting question. I'm not sure how claims can be made in this fashion.
Antibiotics are simply a tool, and they're one of those things, which I think René has talked about too.... We don't want to see our animals sick, but we should first do all the prevention we can so we don't ever get to a point where we have to use antibiotics.
Where they get this claim from, I'm not sure, and I'm not sure about the validity.