Rolling Dogs Can Become Infected with Sarcoptic Mange

By Dr. Kim Everson, DVM

 

It started innocently enough. My rugged yellow Labrador retriever developed an ear infection one summer. No big surprise in a dog that wallows in every mud puddle he can find. I treated it. It returned, this time with a hot spot, or localized bacterial skin infection, on his neck. A logical but unfortunate consequence of itchy ears, I thought. I continued the ear infection treatment and started an antibiotic.

Unexpectedly several new sores appeared. Itchy was an understatement. Even though I religiously apply flea and tick preventative to my country dogs, who consider the tall grass edging our farmyard a tantalizing wonderland of critters, I combed him for fleas. Nothing. I ran skin tests to check for mites, ringworm and yeast infection. Again, nothing spectacularly abnormal.

It being ragweed season, I began cursing my bad luck at having a dog with seasonal allergies. Anti-histamines didn’t help. Not even a course of steroids—the anti-itch medicine of last resort—tamed the awful itch.

One day, after weeks of trials and lots of errors, I looked at him and saw the problem plainly. The skin on his elbows and hocks was thick and leathery. The edges of his ear flaps were bald and scaly. He was starting to look like a mangy dog! I whisked him into my clinic once again, and did yet another skin scrape test. The problem with diagnosing scabies is that “false negatives” are common early on when only a few mites are scattered across the dog making them difficult to detect. It is an allergic reaction to the presence of these few mites that creates such a mess in the dog.

This time I hit pay dirt. I scraped the surface of his bald skin with a small scalpel blade, set the scraped off material in mineral oil on a glass slide and examined it microscopically. I was in luck. Flailing around in the oil were several tiny round insects with eight stumpy legs. Sarcoptes scabiei mites. Sarcoptic mange. Scabies.

With a diagnosis in hand, a cure was finally within reach. I ordered a special prescription heartworm preventative that also treats sarcoptic mange—not cheap, but worth every penny—and within a very short time, the itchiness stopped and his hair regrew.

Although I finally had an answer and my dog was cured, what plagued me now was the question of where he’d gotten mange in the first place. I worried I would finish the treatment just to have to start all over again.

Sarcoptic mange is a contagious mite spread by direct contact with an infected animal. People can be bit by canine scabies and dogs can be bit by human scabies, but a canid host (i.e., dog, coyote, fox) is required for canine scabies to thrive. My dog does not board anywhere and does not socialize with other dogs, not even with the canine patients at my veterinary clinic. Unlike fleas, scabies does not create a long term environmental infestation, so it was unlikely he picked up mange from a wild animal’s “nest” in the weeds.

Finally it dawned on me. Like most country dogs, my Labrador loves to roll in stinky dead who-knows-what. Throughout that spring and summer our neighborhood was haunted by a miserable, mangy red fox. Its appearances stopped weeks before the appearance of that first “ear infection” in my dog, and I wouldn’t be surprised if my dog unwittingly smeared mange mites all over himself one lazy summer day when he happened upon a dead fox.

Nowadays when I’m presented in my clinic with a suddenly über-itchy dog, especially hunting or country dogs, one of the first things I ask is whether they have rolled in something foul lately. Many times the answer is yes, and before they get bald and obvious, they’re being treated for sarcoptic mange.

 

Originally printed in farm news column, Fond du Lac Reporter, April 20, 2014