rust colored stain

Question
I have a 2yr old white standard poodle that developed a rust colored stain. Our vet said the hair follicles in that area has been damaged and the stain will be permanent. She is a beautiful dog, but I wonder if I can bleach the unsightly stained area on her back side.

Answer
Hello Laura,
Your dog most likely had a Black parent in its background which is causing the stains.  It could also be due to an injury (which in white dogs tends to grow in a dark red color rather than white), and will always be that reddish tint.  

You can try a brightening shampoo for white dogs.  Most pet stores will sell a Brightening or Whiting shampoo for white dogs, or Sally's Beauty Supply sells a shampoo for people with white or light colored hair that works pretty well.  
As for bleaching the hair, you can try a bleaching product for people hair, but don't leave it on for as long as you would a person.  It could burn the skin, and as the whites tend to have a more sensitive skin as it is, you will need to be careful.  

It could also be due to your dog chewing the hair in that area.  When the saliva mixes with the chemicals in the hair, this results in the hair being dyed a reddish color.  If your dog chews, fixing the problem of why the dog is chewing on her skin (allergies, fleas, etc.) and thus her stopping her chewing on her skin will take care of those stains.  

You might also look at the dog food she is eating.  Some dog foods contain dyes that will stain the dogs coat and fur.  Check the label and see if Red dye is used in her food.  

I hope this helps you some.  If you have other questions for me, please feel free to ask.

Thanks for using AllExperts.com,
Kim