Demodectic Mange
The Culprit - Demodex Canis
Demodectic mange is caused by a microscopic mite called Demodex canis. All dogs raised normally by their mothers possess this mite as mites are transferred from mother to pup via cuddling during the first few days of life. (After the pup is older it is unable to pick up demodex mites. Puppies raised by hand do not ever get demodex mites.) For some reason, conditions change in certain dogs to allow demodex mites to gain the upper hand; the mites proliferate and can cause serious skin disease.
Mites are not transmitted to people or other dogs except from mother dog to pup as described. Demodectic mange (unlike sarcoptic mange) is not contagious.
Mites live inside hair follicles -- a difficult place for miticides (chemicals that kill mites) to reach.
Mites are a normal residents of dog skin; it is only in some individual dogs that mites cause problems.
Demodicosis -- The Disease Itself
Demodectic mange, also called demodicosis, has three forms:
Form #1: Localized
Usually a red, scaly, well-circumscribed lesion on the face or forelegs is present. It generally goes away on its own. Goodwinol ointment, an insecticide, may be used daily to control localized demodicosis. Hair regrowth should be evident after about a month of treatment; however, some localized cases appear "destined" to become generalized and no treatment will prevent this from occurring.
When ointment is used, rubbing the medication on the area may break off the weaker hairs at the margin of the lesion. The lesion may thus appear to get larger at first. Antibacterial gels are also used against localized demodicosis and associated skin infections. Often it is best not to treat this condition and to simply allow it to resolve on its own.
Enlarged lymph nodes are a bad sign -- often foretelling generalized mange.
Can the Pup Be Bred Later?
Sometimes the puppy with localized demodicosis was obtained for breeding purposes. The current recommendation is not to treat these puppies so that we can determine if the condition will stay localized and resolve or if it will generalize. If it stays localized and eventually resolves without treatment, the animal is still a candidate for breeding. If the condition generalizes to cover the entire body, the animal should be sterilized. If the condition receives treatment and resolves, we will never know how the disease would have gone in its natural state and will not know whether the pup is carrying the genetic predisposition for demodectic mange. In this case, it is best to be conservative and not take the chance of passing on genetic predisposition for this disease.
Localized demodicosis is almost exclusively a "puppyhood" disease. When a puppy develops localized demodicosis the chance of the condition resolving are 90% unless there is a family history of demodicosis in related dogs. In this case, chance of spontaneous resolution drops to 50%.
Occasionally an adult dog develops localized demodicosis. We currently do not have good understanding of the prognosis or significance of this condition in an adult dog.
Form #2: Generalized
The entire dog is affected with patchy fur, skin infections, bald, scaly skin.
Most generalized demodicosis starts as localized demodicosis.
Adult Onset-- Most demodicosis occurs in young dogs. An older dog should not get demodicosis unless it has an underlying problem with its immune system, possibly even cancer. A veterinarian should be consulted regarding possible primary diseases.
Juvenile Onset -- 30% to 50% of dogs under age 1 year recover spontaneously from generalized demodicosis without any form of treatment. Usually treatment is recommended, though, to facilitate recovery.
It is very important that dogs with a history of generalized demodectic mange not be bred as there is a hereditary component to the development of the disease.
Form #3: Demodectic Pododermatitis
This condition represents demodectic mange confined to the paws. Bacterial infectious usually accompany this condition. Often as generalized demodicosis is treated, the foot is the last stronghold of the mite. Old English Sheepdogs and Shar-peis tend to get severe forms of this condition. The infection can be so deep that biopsy is needed to find the mites and make the diagnosis.
Stress and Generalized Demodectic Mange
Physiological stress is an important factor determining the degree of severity of demodectic mange.
Females should be spayed as soon as the disease is controlled. Coming into heat, hormone fluxes, and pregnancy are very stressful. Also, predisposition to demodicosis is hereditary and should not be passed on.
The dog should be fed a reputable brand of dog food so as to avoid any nutritionally related problems.
Keep the pet parasite-free. Worms are irritants that the pet need not deal with and fleas may exacerbate the itchiness and skin infection.
Keep up the pet's vaccinations.
The mites themselves cause suppression of the immune system so the pet needs every advantage to stay healthy.
Skin infections are usually present in these cases and antibiotics will likely be necessary. It is very important that cortisone type medications such as prednisone NOT be used in these cases as they will tip the immune balance in favor of the mite.
Prognosis
The younger the dog, the better the chance of cure. In many cases of adult-onset demodicosis, the disease is controlled by dips and baths but cure is not always possible. Some cases can never be controlled.
Current Treatment of Choice -- Ivermectin
Ivermectinis a broad spectrum anti-parasite medication generally used for food animals and horses. In dogs and cats it is licensed for use as a heartworm preventive aand as a topical ear mite therapy; the use of this medication to treat demodicosis is not approved by the FDA. When ivermectin was a new drug, it was hoped that it could be used against demodectic mange mites as at that time only labor intensive dipping was available for treatment. Once it was discovered that daily doses are needed (most other parasites can be controlled with wormings spaced several weeks apart) ivermectin was found to be highly effective, quickly becoming the treatment of choice. Ivermectin is inexpensive relative to Milbemycin (see below) and involves no labor intensive bathing. It DOES, however, taste terrible if given orally (it may be necessary for the owner to learn how to give ivermectin as an injectable treatment.)
THIS MEDICATION IS NOT SAFE FOR USE IN COLLIES, SHETLAND SHEEPDOGS, USTRALIAN SHEPHERDS, OLD ENGLISH SHEEPDOGS, AND SOME WOULD SAY, ANY HERDING BREED.
There is an unfortunate tendency for people hoping to save money to get their hands on large animal formulations of ivermectin and attempt to home treat this condition. The chief reason why this is a bad idea is "ivermectin sensitivity," a phenomenon famous in the collie breeds. It is important to realize that sensitivity to ivermectin may not be predictably limited to “collie breeds” and thus it is often prudent to use a lower test dose before initiating the relatively high doses of ivermectin needed to treat demodicosis. Recently a DNA test has been developed by Washington State University which can determine whether or not an individual has ivermectin sensitivity. (The test uses a cheek swab - for details visit www.vetmed.wsu.edu/vcpl). Not all individuals of collie heritage are sensitive to ivermectin.
Another important reason not to attempt home treatment of this condition with ivermectin is that there is a range of ivermectin doses used in the treatment of demodicosis and it seems that higher doses do clear infection faster than lower doses. This means that if a lower dose has been ineffective, a higher dose may still work. This does not mean that a pet owner should experiment with ivermectin doses on their own as there is some potential for lethal toxicity if this drug is not used appropriately. It does mean, though, that the affected dog needs to be appropriately rechecked at the proper intervals so that the mite numbers can be checked and it can be determined if the dose should be increased.
A related medication called doramectin can be used to treat demodicosis. It is given as a weekly injection as opposed to daily treatment with ivermectin. The same collie sensitivity exists with doramectin and there is no price advantage so the only benefit over ivermectin, if there is one, relates to the weekly administration schedule.
Traditional Treatment -- Amitraz (Mitaban) Dips
Unless the animal is largely bald or has a short coat, complete clipping will be required for maximal contact with the dip.
Dip should be preceded by a benzoyl peroxide bath (oxydex or pyoben shampoo). This helps clear up skin infections and also helps open the hair follicles so the dip can penetrate to the mites. Shampoo must sit on the pet at least 10 minutes before rinsing. Caution: This type of shampoo can stain jewelry and clothing.
Dip is applied by sponge. Gloves should be worn while applying dip. The dip dries on the dog's fur and should not be rinsed off. The dog should not get wet between dips.
Dipping occasionally yields mild sedation as a side effect. Very small dogs may become highly sedated and require an antidote but this is unusual. For your convenience, dipping and bathing may be performed at the hospital thus allowing for veterinary supervision in the event of side effects.
Dipping/bathing is recommended every 2 weeks on the bottle of dip. Most universities are finding that the cure rate jumps from 25% to 80% when dip is used at double strength and applied weekly. No toxic effects have been seen using the dip in this way and this is our current recommendation except in very small dogs and puppies.
The pet's skin is scraped every 2 weeks until 2 consecutive scrapings are negative. Dipping/bathing is discontinued and the pet is rechecked in one month. Dipping/bathing are reinstituted if mites are again found.
Amitraz dipping should not be used in toy breeds or in very young puppies.
NOTE: Amitraz is a drug of the monoamine oxidase inhibitor class. People who are taking selected serotonin reuptake inhibitors (such as Prozac®) could have a bad reaction to the use of amitraz if they administer dips to pets.
NOTE: Recently Upjohn Pharmacia merged with Pfizer Animal Health. Prior to this, Mitaban dip was on an "indefinite" backorder. Pfizer Animal Health plans to reintroduce Mitaban dip as soon as possible and does not consider this product to have been discontinued. Large animal formulations of Amitraz are available but their use in small animals is considered to be off-label. If you are interested in Amitraz therapy for demodicosis, consult your veterinarian.
Something Else Your Veterinarian Might Try -- Interceptor®
Interceptor (active ingredient: Milbemycin oxime) is normally marketed as a monthly heartworm preventive; when it is used on a daily basis, it is effective against generalized demodicosis. This discovery was welcomed by the veterinary profession as finally demodicosis could be treated without labor-intensive dipping. The downside to this treatment is expense, plus an owner can expect to be using this medication daily for up to 3 months to achieve cure.
Interceptor may be used in any patient safely; the only downside is expense.
Relapse?
Relapse is always a possibility with generalized demodicosis but most dogs that relapse do so within a 6 to 12 month period from the time they appear to have achieved cure. When relapse occurs it is often because the dog appeared to be normal and the owner did not return for the appropriate rescrapings. The final scrape is performed one month after treatment has stopped.
Sarcoptic mange is a completely different disease.
We Wish it Wasn't Necessary to Add This
No Motor Oil
Some 30 years ago, dipping dogs with demodectic mange in motor oil was a popular home remedy. Skin exposure to motor oil can cause rashes and skin destruction in severe cases. The hydrocarbons can be absorbed through the skin and cause a dangerous drop in blood pressure. If motor oil is licked off the coat, resultant vomiting can lead to aspiration of motor oil into the lungs and pneumonia. Kidney and liver damage can result from motor oil dipping.
Please: Do not dip your dog in motor oil!
“No Matter What You Are Told, No Line is Free of Health Problems”
If you are told this, do not believe it: it is idyllic and not at all true! Any person who tells you this is either not thorough enough in his/her research, has not been breeding long enough to learn about the pedigrees, or is just lying, so be overly cautious. (From statements by Peggy (Bob) Adamson)
Longevity
There is yet another complexity to making a breeding decision – longevity. This is a CRITICAL factor to consider since some dogs may test clear for all diseases and yet come from a pedigree where the average life span is 7 years of age. Conversely, a dog may test positive for hypothyroidism yet come from a line of 13 and 14 year old relatives. When talking about cardio, cancer or CVI (“The Big Three” in Dobermans), a dog who tests positive and/or dies of one of these genetic diseases has often contributed to the gene pool prior to the diagnosis or death. By the time the diagnosis is made, 3 or more generations of progeny can be alive and well. At this stage, it is unrealistic for a breeder to toss out all of the dogs in his/her breeding program and start again with new dogs who may have the same health problems or even more! It is for these reasons that the entire dog and pedigree must be considered prior to making a breeding decision.
Given all of the information presented above, it is important to consider both the health results of a given dog as well as the overall longevity represented in the pedigree. For certain tests there are definitive results: vwd and hip dysplasia. For most, however, there is no surefire way of knowing if a dog will ever develop the disease. Cardio, cancer, CVI, eye disease and hypothyroidism all qualify here. The best we can do is to ensure that these tests have been passed at the time of breeding and that there are minimal occurrences of these diseases in the bloodline and pedigree.
One of the most critical things to consider when breeding a litter is health and longevity. These two things are not synonymous, nor are they mutually exclusive, so it is extremely important to consider both factors when making a breeding decision.
With the average life expectancy of Dobermans being under 10 years of age and Weimaraners approximately 12, it is becoming increasingly important for breeders to pay more attention to hereditary diseases. Some of the most common diseases affecting Dobermans are cardiomyopathy, cancer, hypothyroidism, Von Willebrand’s Disease, eye diseases and Cervical Vestibular Instability (Wobbler’s). Weimaraners are commonly affected by HOD, cancer, torsion and hip dysplasia.
Cardiomyopathy is the big killer in Dobermans, being the #1 cause of death in males and the #3 cause in females. It is a disease which affects the heart, and once diagnosed a dog can expect to live only a short time (even with the best medications, 2 years is a long addition). There are some screens in place to diagnose this disease, but due to its complexity there is no definitive (i.e. DNA) test. The most reliable test we have right now is the Holter Monitor. This device is strapped onto the dog., and it monitors and records the beating of the heart over a 24 hour period. See http://frontpage.execulink.com/dobes/holter.htm for more information. The disease rarely occurs in Weimaraners, though it has been seen in recent years.
Cancer is the #1 cause of death in female dogs of many breeds, with the most common being mammary. A simple spay procedure done prior to the bitch’s first heat cycle can reduce the probability of cancer by up to 90%. Therefore, it is recommended that all non-breeding stock be spayed at an early age to reduce the likelihood of cancer. As in humans, there is no genetic test to determine if a dog will develop cancer, so we must rely on pedigree research. Vets and other animal specialists are investigating the links between cancer and nutrition and over vaccinating.
Cervical Vertebral Instability (CVI or Wobbler’s) is a disease affecting the spine and neck of a dog. It is a disease primarily found in Dobermans and Great Danes as well as some breeds of horses. Most often, Dobermans will be affected with this disease between the ages of 4 and 5. Although it is the neck area or the fifth and sixth cervical vertebrae that are affected, an affected dog will initially lose movement in its rear and will actually ‘wobble’ when trying to maintain its balance. As the disease progresses, the dog will become more limited in its movement and is often in extensive pain. The pain can be controlled with steroids, and the dog can maintain a moderate quality of life if precautions are taken. Exercise should be limited, stairs should be avoided and no pressure should EVER be placed on the neck (so no collars should be used). For this reason, not a lot of research has been conducted on CVI. If you have a dog diagnosed with CVI, a terrific alternative to surgery and steroids is Gold Bead Implants by Dr. Terry Durkes.
Hypothyroidism in dogs is much the same as in humans. Affecting the thyroid gland, it can have devastating effects on an affected dog. Symptoms include shedding, poor coat, and in extreme cases fainting. The disease rarely results in death, but is something to consider when breeding, as daily supplementation can be required for an affected dog. This can be both expensive and a nuisance over time. An annual complete thyroid panel (checking the levels of TSH, T4, T3, Free T3, Free T4 and Thyroxin) should be conducted on dogs to ensure proper maintenance and control of the thyroid. This disease is believed to be genetic, and some bloodlines are heavily affected with it while others remain relatively clear. An interesting bit of information is that red Dobermans are more often affected than black Dobermans.
The Canine Eye Registration Foundation (CERF) is an organization which certifies dogs who have tested clear for genetically transmitted eye diseases such as cataracts and glaucoma. It is estimated that approximately 40% of purebred dogs suffer from eye disease. Exams must be done annually and submitted to CERF for current registration.
Hip dysplasia affects many breeds of purebred dogs. Hip x-rays can be taken at any age. X-rays should be taken by a qualified vet/radiologist and then sent to the Orthopedic Foundation for Animals (OFA) to receive a registration number and a rating. If the dog is less than 24 months of age, a preliminary result will be issued, but for the result to be considered final, the dog must be more than 24 months of age when the x-rays are taken. To get a rating, three qualified radiologists from the OFA read the x-ray (2 for a preliminary result). Possible ratings are: excellent, good, fair, borderline and dysplastic (levels I, II, III). Once a dog receives an OFA number, this result is considered the dog’s final evaluation. OFA houses the largest animal health database in the world. They have a public registry for hip and elbow dysplasia, VWD, Thyroid, CERF and cardiomyopathy. However, only dogs who have passed these tests are recorded in the database. It is the responsibility of the owners to submit their dogs’ results to OFA and to authorize OFA to make this information public. However, it is still an excellent source of information.
There is also a second (and preferred by us) method of testing for hip dysplasia. This is the Pennhip method. X-Rays can be taken and evaluated as early as 4 months by this method. The hips are measured for the amount of laxity they have in the joints, evaluated for degenerative joint disease and for fluid in the joints. Three different views of x-rays are taken, and veterinarians must be specially trained and certified to take these x-rays. Each dog is evaluated against other dogs *of the same breed* and then ranked in a percentile. We feel this is a better tool for evaluating hip dysplasia and also a better tool for enabling us to improve the hips of our dogs over generations. For more information see The Pennhip Website.
Von Willebrand’s Disease (VWD) is a bleeding disorder affecting mainly Dobermans, Shelties, Scottish Terriers, Manchester Terriers, Corgis and Poodles. Some of these breeds suffer from Type 3 VWD which is an extremely serious form of the condition where dogs can spontaneously bleed. It can be a death sentence for a dog. Luckily, Dobermans are not in this category. Dobermans suffer from Type 1 VWD where they may be genetically affected with the disease but rarely exhibit signs of bleeding. They will never bleed spontaneously because they still have Von Willebrand's Factor circulating through their systems, and most bleeding can be easily and safely controlled.
There is a DNA test for VWD, and two labs in the USA are offering this test. The disease is a simple recessive disorder which has made a DNA test much easier to identify. Every dog has two genes for VWD. Each of these genes may be a clear gene or an affected gene. Dogs who carry two copies of the clear gene are considered CLEAR, dogs with two copies of the affected gene are considered AFFECTED and dogs with one copy of each gene are considered CARRIERS. Please note that affected dogs RARELY exhibit clinical signs of the disease. Also note that carriers do not actually carry the disease, but rather carry one copy of the gene. They will not exhibit ANY clinical signs of the disease.
Breeding two clear dogs is optimal, however this should not be the only criteria for selecting a breeding pair. Temperament, longevity and conformation as well as pedigrees MUST be considered too. Breeding two affected dogs will result in an entire litter of affected dogs. Two carriers will result in 25% clear, 25% affected and 50% carriers. A clear to an affected will result in 100% carriers. An affected to a carrier will result in 75% affected and 25% carriers. Clear to carrier will result in 75% clear and 25% carriers.
Hypertrophic Osteodystrophy (HOD) causes lameness and extreme pain in young growing dogs, usually of a large breed. It appears to occur in Weimaraners as a vaccine reaction. In this case, it usually occurs a few days after distemper vaccination and may appear to be worse than the "average" case on radiographs. HOD usually shows up as an acute lameness, often seeming to affect all four legs simultaneously. Affected dogs may stand in a "hunched up" stance or refuse to stand at all. They may have a fever but this is not consistently present. They usually have painful swellings around the lower joints on the legs. Some will die from this disease, some suffer permanent disability but many recover later. The disease is so painful that many owners elect to euthanize the puppy rather than watch it suffer, despite the reasonably good chance for recovery, long term. Affected dogs may be so ill that they refuse to eat.
X-rays confirm this diagnosis in most cases. There are very typical X-ray changes, although it can look a little like bone infection from a septic condition. There is some evidence at this point that viral or bacterial infections may underlie some cases of HOD as canine distemper virus has been found in the affected areas in some dogs. There can be high white blood cell counts and the alkaline phosphatase level in the blood stream is often elevated.
Longevity
There is yet another complexity to making a breeding decision – longevity. This is a CRITICAL factor to consider since some dogs may test clear for all diseases and yet come from a pedigree where the average life span is 7 years of age. Conversely, a dog may test positive for hypothyroidism yet come from a line of 13 and 14 year old relatives. When talking about cardio, cancer or CVI (“The Big Three” in Dobermans), a dog who tests positive and/or dies of one of these genetic diseases has often contributed to the gene pool prior to the diagnosis or death. By the time the diagnosis is made, 3 or more generations of progeny can be alive and well. At this stage, it is unrealistic for a breeder to toss out all of the dogs in his/her breeding program and start again with new dogs who may have the same health problems or even more! It is for these reasons that the entire dog and pedigree must be considered prior to making a breeding decision.
Given all of the information presented above, it is important to consider both the health results of a given dog as well as the overall longevity represented in the pedigree. For certain tests there are definitive results: vwd and hip dysplasia. For most, however, there is no surefire way of knowing if a dog will ever develop the disease. Cardio, cancer, CVI, eye disease and hypothyroidism all qualify here. The best we can do is to ensure that these tests have been passed at the time of breeding and that there are minimal occurrences of these diseases in the bloodline and pedigree.
ALBINISM - "white coated" and "white factored" Dobermans should NOT be bred. These dogs are *TYROSINASE POSITIVE ALBINOS*. In 1996, the AKC established a tracking system (the letter "Z" will be part of the registration number) allowing breeders to identify the normal colored Dobermans which may carry the albinistic gene. All breeders should require an AKC certified pedigree with colors to check that "white coated" and "white factored" dogs are not present in the pedigree of the dog or bitch to be bred.
