What's causing my dog's brown skin, if it's not fleas or ticks?

It's a little odd that it is only on one side of the belly/leg. The rust color looks like saliva staining from your dog licking more frequently. The brown spots are likely clogged pores. I would work with your vet to treat itching (making sure he is on a good-quality flea preventative), food allergies, atopy, etc. You can also ask for a benzoyl peroxide dog shampoo to help flush the pores.

Thanks for using Petco Pet Education Center, formerly Petcoach! This could be a skin infection. You can try to use a medicated shampoo containing chlorhexidine twice weekly for 2 weeks. If there is no improvement or in the meantime this appears to be getting worse, have her evaluated by a veterinarian for further assessment and treatment. Good luck and have a good night!

Poor Chalie! Black discoloration in the skin can occur as a result of chronic inflammation (from infection, fleas, allergies, etc.) or due to endocrine/metabolic conditions (such as hypothyroidism or Cushing's disease). Make sure that Chalie is receiving a high quality flea preventative (such as Nexgard, Bravecto or K9 Advantix II) regularly. You can also try bathing him in a gentle oatmeal based dog shampoo, because this can be soothing on the skin. I also recommend taking Chalie to his vet for further evaluation of his skin to determine if there are more chronic conditions that should be addressed. I hope that all goes well!

The brownish-red discoloration on your dog's face looks most like salivary staining. The enzymes in the saliva interact with the fur, causing this type of reddish-brown staining. Salivary staining generally occurs when a dog licks a particular area excessively, like the paws or groin, or when they drool a good bit. It's especially noticeable in white dogs, like your adorable pup. Some dogs may drool excessively if they're nauseous, so keep a close eye on your dog for changes in their appetite, vomiting, or lethargy, as these could be signs of a medical issue. If your dog is otherwise doing well, allergies are often to blame (particularly this time of year). You can try bathing your dog with a gentle oatmeal shampoo. It's best to seek veterinary attention if you see this discoloration elsewhere on the body, as this indicates that your dog is itchy if they're licking a lot, and would likely benefit from additional treatment. I hope that everything goes well!

Mila's signs could be indicating allergies as well as a skin infection. The skin color changes could be due to this being an ongoing/chronic issue. Sometimes an oatmeal based shampoo helps as well as omega3 fatty acid supplements but if your dog has allergies your veterinarian can discuss long-term control plans with you.

It's possible it's dirt or debris that Charlie laid in. Flea feces can also look like this. Collect a few of those dark colored flakes on a clean white paper towel and apply a few drops of hydrogen peroxide. Then gently rub it around. If the towel turns reddish or rusty colored, it's flea feces. It looks like Clay does have a few lesions so a skin rash or infection is very likely. Your veterinarian can help to treat this rash effectively. I hope this helps and please feel free to post any additional questions.

Skin darkening can occur due to natural aging, low level irritation from infection or allergies, a healed wound or changes in hormone levels from hypothyroidism. Your veterinarian may be able to determine the exact cause after a thorough physical exam. I hope this helps and please feel free to post any additional questions.