Hair loss

[Ohiohntr]

I have one female that literally has no hair on the inside of her ear flaps. I keep Nu-Stock on them to fight infection but it is as if she has worn it off. This same female has nearly no hair on the top side of her muzzle/nose. Both of these problems seem to have just come on since running alot in the crusted snow. Another one of my other dogs has developed the same problem going on with the top of his nose as well.....is this normal when running in old icy snow?

BTW- both of these hounds drag their noses in the snow whereas my other two run with their "head up" and they have not lost any hair.