Pure Dog Talk 398 – Getting Under the Skin: Demodex and other Mites Pure Dog Talk is the voice of purebred dogs. We talk to the legends of the sport and give you the tips and tools to create an awesome life with your purebred dog. From showing to preservation breeding, from competitive obedience to field work, from agility to therapy dogs, and all the fun in between. Your passion is our purpose. Pure Dog Talk is proud to be sponsored by Trupanion, medical insurance for pets. Vet bills can be expensive and the Trupanion policy can help cover the cost of unexpected accidents or illnesses. Easing the financial burden by taking cost out of the equation, when your pet is sick or injured. Additionally, Trupanion has the ability to pay the vet directly at checkout. So you pay less out of pocket. If you're a breeder, you can also send your litters home with the same great coverage with their breeder support program. You can learn more following the link on the website, puredogtalk.com. And don't forget to mention, Pure Dog Talk send you. Laura Reeves: Welcome to Pure Dog Talk. I am your host Laura Reeves and I am always happy to talk to my friend, Dr. Marty Greer, who is our veterinary voice here at Pure Dog Talks and I have more fun with Marty than almost anybody. So welcome Marty. Dr. Marty Greer: Thanks. I'm glad to be here. Laura Reeves: I'm glad you're here too. And we're going to talk about demodex, which is demodectic mange which is a type of mite. And there's lots of different things that go with this. And this was actually a listener request who had an Australian Shepherd. And since the treatment, for some types of demodex, Ivermectin this was a concern. So I'm excited. I'm excited to hear what you have to say on this and what do we start with? Dr. Marty Greer: Oh, well, gosh, we can start with the history of demodex which used to be very serious. When a dog was diagnosed with demodex back in the day, it was sometimes a death sentence. So it was quite serious. I remember seeing dogs die of demodex when I first got out of veterinary school. Laura Reeves: Really. Dr. Marty Greer: Yes. Yeah. I saw a dog that died from demodex when I was working in California in 1980, back in the old days when you used to have to ride a bicycle to run the electricity, to run the X-ray machine. Yes. [crosstalk 00:02:27]. Laura Reeves: When Davy Crocket was just a boy… Got it. Dr. Marty Greer: So, I remember a little docks and we put them on Levamisole because that was this dewormer that we thought would help his immune system. And in reality, that even wasn't enough. So over the years, we've seen a huge change in the medications that we have as an option to treat demodex with. And it is no longer the scary, awful death sentence that it once was. But I still think we need to talk about demodex as far as clinical signs and what that means for our breeding program and what it means to your dog's health. So there's still quite a bit of information here that we need to go over. Laura Reeves: Absolutely. So I think we could start with the kind of baby puppy demodex that you see where they have a little bit of hair loss, maybe underneath their eyes, where I have seen it often triggered by, I understand stress. Is that accurate? Or talk to me a little bit about that. Dr. Marty Greer: Well, there's probably a component of stress that goes with it. We know that it is an immune mediated disease. So we believe it's a B-ell deficiency that the immune system doesn't have actively functioning or well enough functioning B- cells in some of these patients. Because every single dog at birth is exposed to demodex. So as it passes through the birth canal, or if it comes out through a C-section incision, as soon as it starts to nurse and it's exposed to its mother's skin, they're exposed to demodex. Laura Reeves: Demodectic mites just live on our skin, on the dog skin, is just a thing. Dr. Marty Greer: Yes. It's a thing. It's part of the normal flora in very small numbers. But our immune system typically keeps it under control. And if your immune system isn't doing what it should be doing, then that's when the numbers of mites increase to the point that you have lesions. And there's basically two categories of demodex. There's localized demodex and generalized demodex. So localize is exactly what you described, the baby puppy with a little hair loss under their eyes, maybe a couple of patches someplace on their leg or their trunk. Just a little patch of hair loss. It's not itchy. It's not uncomfortable. It doesn't look angry. It's just this little patch that you don't see hair, frequently around the eyes, but not exclusively there. And a lot of people come in and they're like, "Oh yeah, well, he's just been fighting with his brother. It's no big deal." And you do a skin scraping and you find 30 demodex. Well guess what? You have demodex, You don't just have a puppy fighting with it's brother. So the first thing we will always want to do when we see a skin lesion on a young dog is to do a skin scraping. And we shouldn't be so cavalier that we just start them on Bravecto or some other medication and say, "Well, don't worry about it. We'll just get rid of it." I think it's important that you have a diagnosis, especially if you have a breeding program and you need to know whether you have demodex in your line. So I think we shouldn't blow off doing skin scrapings. And demodex show up pretty readily on a skin scraping. There's a number of different kinds of mites that we can see in dogs and cats and demodex is one of the easiest ones to find on a skin scraping. So it's actually kind of exciting for a veterinarian or a veterinary professional. Because you find the mite under the microscope and you're like, "Oh, everybody needs to come look at this, this is really cool." It's not really cool if it's your dog. It's really cool if you're the veterinary professional. Laura Reeves: Right. Dr. Marty Greer: Because it's really cool. Because looking into the microscope, seeing nothing is boring. So it's cool to see something interesting. So that's the first thing we need to realize is that they're pretty easy to find if they're there in enough numbers to find them on a skin scraping you have demodex, period. Laura Reeves: So in baby puppies, here's my question, I have seen it resolve as the puppy grows as its immune system gets stronger. Dr. Marty Greer: Right. And that's really common in the localized form of demodex, but then there's generalized demodex. And when my daughter was about three, we had a little pug that came to the practice. My kids used to go to work with me everyday, I had a daycare. Babysitter upstairs that took care of my technician’s children and my children, and so it was great. But she came peeling down the stairs one day into the main part of the clinic. And there was this adorable little black pug standing in the middle of the treatment area. Dr. Marty Greer: And Katie was about three years old, my daughter. And she stopped dead in her tracks about 10 feet away from the puppy and her eyes got big and she took three steps backwards. And she looked at her and she's like, "Ooh." Because this pug puppy had no hair on the top of her head. You could see the little eyeballs and a completely bald black pug head. Laura Reeves: Oh my gosh. Dr. Marty Greer: And I said, "Honey, it's okay. You can touch the puppy." Because I knew the puppy had demodex because I had already scraped it. I knew the puppy had demodex and I knew it wasn't contagious to my daughter because human demodex and dog demodex are different demodex. She's three and she's looking at me with these big saucer eyes looking at me like, "Nope. Not touching that. Because I don't know what that is, but that's not the way a pug is supposed to look." So it can be generalized, even in very young puppies, we can see generalized demodex. And that's the kind that used to kill dogs, not the localized, localized ones weren't serious, but generalized demodex caused enough hair loss and enough breakdown of the skin barrier, that... Your skin is a barrier to the rest of the world from all of the invading. Laura Reeves: Right. Dr. Marty Greer: And so if enough demodex lived in the skin, then your body was just invaded by other bacteria and other things that happened.