Lastly, in silky coated small dogs
such as poodles, another potential reason for localized hairloss on
the thigh would be a rabies vaccine reaction; this is diagnosed by skin biopsy. I recommend taking your puppy to your veterinarian to have the lesion examined to identify the cause, and appropriate treatment.
Kimberly Coyner, DVM DACVD
Dermatology Clinic for Animals of Las Vegas