I've got a trip to the vet scheduled but I'm concerned if this may be mange?? My 5month old pup has red spots on his neck and chest, and in some the fur is missing. Not massive spots but enough for a mommy to worry! He doesn't ever itch at it so I'm wondering if it's just from too much rough-housing with our other dog?? Has anyone else ever experienced this or have any advice? Thanks you!