A lot depends on genetics. My bitch seems to have strong ears and puts that into her puppies. I also think size plays a part in it. I have a litter and the smallest females ears were up and stayed up at 4 weeks. The other two females were up by 7 wks, the males second ear finally came up to stay at 8 wks. I have seen puppies at 12 wks that didnt have both up yet, but within two weeks they were.
Some one mentioned diet playing a role in ear development. These puppies were raised on a raw diet and perhaps the bone in their food helped with giving the body the calcium and minerals needed to develop teeth and ears. I really have no idea though.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.