Llama and alpaca really don't count. They are much smaller and much weaker than cattle. You can breed them to be bigger, but there may be limits to that; there may also be a path dependence to it, in that they started in one economic niche and there was no reason for a concerted effort over dozens or hundreds of generations to make them stronger.

Bison are much more problematic IMO for Diamond. The most I've seen on them is that they are surlier than cattle. But it's not like aurochs were cuddly fur friends in the beginning either.