I don't have any knowledge about the play fighting and damage to ears, but it seems prudent to break up any squabbles where ear-biting is concerned, if only for your own nerves.
Anything that will encourage vigorous chewing will help to strengthen the muscles in the head that are used to hold up the ears. Just be a bit cautious about leaving puppies unsupervised with anything that could be a choking hazard. But as long as you're there to watch over them, you could offer any of the store-bought chew toys. Alternatively, you could offer raw bones (turkey necks, beef or pork ribs, lamb shank) from the grocery store for chewing fun.
As I'm sure you've already read here, ears go up and down in all kinds of crazy ways until the pups are done with teething, so I wouldn't be too concerned about them being up until 5 months of age.
Anything that will encourage vigorous chewing will help to strengthen the muscles in the head that are used to hold up the ears. Just be a bit cautious about leaving puppies unsupervised with anything that could be a choking hazard. But as long as you're there to watch over them, you could offer any of the store-bought chew toys. Alternatively, you could offer raw bones (turkey necks, beef or pork ribs, lamb shank) from the grocery store for chewing fun.
As I'm sure you've already read here, ears go up and down in all kinds of crazy ways until the pups are done with teething, so I wouldn't be too concerned about them being up until 5 months of age.
