- Inheritable Conditions - Inheritable Conditions
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| What to Do, What to Do? |
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Hips and Elbows |
Thyroid |
Sub Aortic Stenosis | |||
Bloat |
Eyes |
Epilepsy | |||
Adrenal Glands |
Cancer | ||||
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The following is ©1997 - David J. Sheckler. All Rights are Reserved.
(DISCLAIMER - This article is for information purposes only. This information, in no manner or form, is intended to take the place of a Veterinarian/Client relationship. Consult your Vet for your animal's health!)
The popularity of the Bouvier is increasing. The incidences of some health conditions are getting more "press", both on the Internet and within various media. What is a Bouvier Owner or Breeder to do?
Well, the simple (but correct) answer is to understand those conditions, and develop a sound genetic plan to minimize those conditions. The incorrect (but increasingly heard) answer is to say that "We don't have that problem"..... Burying your head in the sand will not make the conditions go away. Testing your animals (OFA, CERF, PennHip, et.al.) is an absolute necessity, taking the bloodline information on these results (siblings, parents/ancestors, all progeny) into account, and figuring out how to adjust your breeding plans.
To say the "sky is falling" is not true. To say that "there are no problems" is not being honest. The genetic health of the Bouvier is somewhere in between. In general, the Bouvier is considered to be a "healthy" breed.
Several years ago, the ABdFC endeavored to survey the membership in 1994 find the prevalence of specific genetic conditions in the Breed. This data was compiled by Judy Abramsohn, and published in the December 1994 issue of the ABdFC's Dirty Beards Magazine. It was not designed to be a scientific study to obtain percentage incidences within the breed, rather than to give some direction of what the "hot buttons" might be.
Recently, the ABdFC has again endeavored to survey the Bouvier Community, this time attempting to perform a scientific study to determine actual incidence rates within the Bouvier. The results of the ABdFC Genetic Health Survey have recently been published.
The following sections are not meant to replace any consultations which you should have with your Vet. They are presented to give a quick summary of the condition and links to Internet information.
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In recent years, the press (canine and general) have probably given more ink to dysplasia of the hips than to any other disease. Recently, attention is also being focused on elbow dysplasia in Bouviers, as more breeding stock is being tested. Simply put, dysplasia of the hips or elbows is the abnormal formation of the joint structure. Both hips and Elbows are being certified by the Orthopedic Foundation for Animals (OFA), and a new methodology for rating hips has been introduced by PennHip.
It is unfortunate that some Breeders and Owners have the view that if a dog can move well enough to move/win in the Show Ring or at Herding Trials, then the hips and elbows are obviously acceptable. Hips and elbows don't always show pain or poor movement until later in life, and some dogs develop compensatory structures around the joint that allow acceptable movement long-term.
Dysplasia is considered to be a genetic condition, and the OFA has taken great pains to demonstrate the betterment of the statistics over the years by taking Hip Ratings into account whenever breeding animals. Recent data also highlights increased risks on large/giant breeds from environmental factors relating to growth rates and weight. Some groups push the positive effects of Vitamin C, but there is no conclusive scientific evidence to support that claim.
Hips and elbows should be tested to the proper protocols (OFA, PennHip, OVC in Canada) in any dog that is going to be used in a breeding program. Further information may be valuable from also testing all littermates of breeding stock, even though they are not intended for breeding.
Unfortunately, OFA Hip and OFA Elbow Registries are currently "closed" registries which publish only those dogs that pass certification. There is no current method in Bouviers (the ABdFC presently has no interests in a Open Registry) to obtain data on non-passing hips/elbows so that more educated breeding decisions can be made.
Joint diseases have been treated with a variety of products, and recently a promising anti-inflamatory (NSAID) was approved for use in canines. Rimadyl is a oral drug produced by Pfizer, and has shown excellent clinical efficacy against the pain and joint inflamation commonly seen with dysplasia and other arthritic joint symptoms (consult with your Vet on use and potential adverse effects). Other approaches to joint pain/inflamation (enteric coated aspirin, glucosamines, MSM, Vitamin C) have had variable success, but may be worthwhile.
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Thyroid diseases are catagorized into two general types - overactive thyroid glands (hyperthyroidism) and underactive thyroid glands (hypothyroidism). Clinical hypothyroidism is found much more prevalently, and is a real concern in Bouviers.
Thyroid disease is categorized into two broad types for clinical hypothyroidism, one being Autoimmune Thyroiditis (Hashimoto's Disease), the other being Idiopathic Hypothryroidism (literally, "idiopathic" means "cannot be attributable to other causes"). Both exhibit similar affects on T4 (thyroxine) and T3 (triiodothyronine) concentrations, and to most extents on TSH (thyroid stimulating horomone) values. In clinical hypothyroidism, levels of T4 and T3 are depressed, and TSH values can be elevated in an attempt to stimulate the production of more T4 and compensate for low existing levels. Autoimmune Thyroiditis is characterized by the existance of Thyroglobulin Auto-Antibodies (TgAA for short).
Although onset may be variable in age, hypothyroidism is most commonly seen between 4 and 10 years old. Deficiencies in thyroid hormones affect the function of ALL organ systems, and as a result may be seen as very diffuse clinical signs - many of the signs are directly related to the slowing of the animal's metabolism from low thyroid hormones.
Overall, you may see some changes in mental accuity, lethargy, intolerance of exercise, and/or weight gain without any corresponding increase in food intake/appetite. With the decreases in metabolism, the dog may have some difficulty maintaining normal body temperature, consequently seeking "warm" places to put themselves. Changes in the skin and coat are very common, and one of the most telltale signs of clinical hypothyroidism, as dry skin and dull coat are common dermatologic effects of the changes in cellular metabolism. Thickening of the skin, hair thinning (or on the extreme case, allopecia) can be symptoms of more involved hypothyroidism.
Hypothyroidism is considered to be a genetic condition, and the OFA has recently instituted a Thyroid Registry to certify acceptable dogs.
There have also been hypotheses forwarded by Dr. Jean Dodd and others which suggest that secondary hypothyroidism is a byproduct of over-vaccination and other immune system "insults". The data on these hypotheses are scientifically inconclusive, though.
Stress is also known to precipitate endocrine changes, including thyroid function changes.
Hypothyroidism is treated by the admistration of oral doses of thyroxine (trade name is Soloxine), which is calculated at the dogs body weight and level of deficiency. Although some people have felt that the 'old glandular derived thyroid pills worked better (presumably from the mixed dosage of both T4/T3), care should be taken with your Vet, as there is signficant variablility in drug levels and absorbtion of the product in the glandular derived products. Thyroxine is the current treatment of choice. Retesting at periodic intervals is recommended by most Vets, as thryroid function may change over time.
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Sub aortic stenosis is a heart condition where fibrous lesions appear on the ascending aorta/left ventriclar septum anatomy of the heart. The more severe the lesion, the more restricted is the bloodflow from the heart out through the aorta, with the potential for cardiac failure in severe cases. This may picked up either by a vet during a cardiac exam where a heart murmur is detected and confirmed (not all heart murmurs are SAS, though), or if a dog is suspected of cardiac problems from behavior (exercise intolerance, fainting, congestive heart failure) and then confirmed by a cardiac exam.
SAS can be so mild as to be asymptomatic (no apparent outward symptoms), or so involved that the dog may suddenly die (sometimes attributed to "heart attacks"). SAS is known to exist in Bouviers, but actual incidence levels is not well known as attention has only recently been focused on the condition.
SAS has been shown to be a genetic condition on studies of Newfoundlands, and the inheritance mode appears to be dominant with variable expression (possibly polygenic). Studies are ongoing, and several Veterinary Colleges are working with Goldens and Newfoundlands in an attempt to obtain a DNA test for this condition.
Treatment of SAS has been frustrating. Mild cases are generally left untreated, as affected dogs are usually asymptomatic. Moderate to severe cases have been treated with medicines aimed at decreasing clinical symptoms (such as congestive heart failure), but those medicines do not affect the underlying condition. Clinical studies have been ongoing to determine whether surgical intervention (balloon angioplasty) are beneficial, but results are not conclusive at this time.
SAS is a potentially severe, debilitating condition for the dog, and a saddening situation for the family. It is the responsiblity of all breeders to check their bloodlines, and ethically breed to remove the condition from the breed. Understanding the genetics of the condition is important -- two OFA Certified parents can produce affected progeny on account of the parents' genetic carrier status.
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Bloat (technically known as acute gastric dilation-torsion), is an extremely dangerous condition which can kill a dog before the owner may know what is happening. Bloat is the swelling of the stomach, with rotation to cut off blood flow and to prevent evacuation of the contents. Bloat is a life threatening medical emergency.
Dogs suffering from bloat appear extremely restless, will probably be salivating and drooling, and may unsucessfully attempt to vomit (to clear the stomach). The abdomen is severly distended, and tapping gently on it will produce a "drum-like" thump. A dog can quickly go into shock, and the condition may be fatal if not treated as an medical emergency. Time is of the absolute essence, and obtaining emergency Veterinary care immediately is the most important factor on the survival of the animal.
Bloat has been suspected to be a genetic condition, but studies have not been scientifically conclusive. Bloat has a tendancy to show up in large, deep chested dogs, and is a known problem in Bouviers.
Treatment of Bloat is by immediate surgical intervention. Current surgical technique decompresses the stomach, repositions it in the abdominal cavity, and may surgically-staple the stomach to prevent further torsion of the stomach and intestines.
Prevention of Bloat is a common practice among owners of large chested breeds. Some suggestions and measures to reduce the risk of bloat:
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Several eye conditions exist in Bouviers, all with relatively low incidences if CERF data is reliable.
Glaucoma is the increased intra-occular pressure within the eyeball. The increased presssure destroys tissues within the eye, particularly the retina and optic nerve. Complete or partial vision loss is the eventual outcome, which may occur gradually or with a sudden onset. The eyeball will often be enlarged and bulging, and the cornea will be hazy and lack transparancy. Glaucoma may be primary (congenital) or secondary (caused by other eye damage). Glaucoma is a serious situation which needs Veterinary medical or surgical attention to releive the pressure within the eyeball. Most cases of Glaucoma end in blindness, although temporary alleviation of symptoms is possible. It is not clear whether primary Glaucoma is a genetic trait or not.
PRA (Progressive Retinal Atrophy) is a genetic condition where the vision cells of the retina gradually degenerate, leading from partial loss of sight to eventual blindness. Onset of the disease is variable, and is progressive over the animal's lifetime. Initial signs are impairment of night vision. There is not treatment for this disease. Some breeds now test by ERG early in life to determine early stages of PRA.
Cataracts are any opacity in the lens of the eye. Cataracts present a varying degree of vision loss, depending on the amount of lens impacted and the position on the lens. Primary cataracts are considered genetic, while secondary cataracts (caused by eye trauma) are generally environmental. It is important to consult a Opthalmic Veterinary Specialist to determine the type of cataract which may be present, so as to know whether your dog is a genetic carrier.
Entropian and Ectropian are conditions of the eyelid. Entropian is the inversion of the eyelid in towards the eyeball, while ectropian is the eversion of the eyelid away from the eyeball. Ectropian is not likely to be painful, whereas entropian is very often painful because the eyelashes contact the eyeball. Both can be surgically repaired, and both conditions may be congenital or secondary from injury. Despite the relative common occurrance in many breeds of dogs (and existance within in the Bouvier) the genetic component and inheritance mode is unclear.
CERF (the Canine Eye Registration Foundation) has set forth certification criteria for acceptable eyes (similar to how OFA has set forth criteria for other conditions). Exams must be performed by a Board Certified Opthamic Veterinarian. Initial certification is for a one year period, and re-examination (and recertification) is required on a periodic basis.
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Epilepsy is a functional disease of the brain characterized by recurring periodic seizures or convulsions. These neurologic disorders present themselves with unusual brain electro-physiology, and can be caused by a number of factors, both environmental and congenital.
Environmental sources can be such as head trauma, viral/bacterial/fungal infections, brain tumors, chemical intoxication (i.e. pesticides, lead, strychnine, and other toxic chemicals), or various bodily endocrine or physiologic states (e.g. hypocalcemia, certain vitamin or severe thyroid deficiencies, severe low blood sugar, hyperthermia).
Where no apparent cause for the seizures or convulsions are evident, the condition is called "idiopathic epilepsy", which should be a signficant concern for Breeders.
Idiopathic Epilepsy has been shown to have a strong genetic component in some canine breeds, and some forms of the condition have been shown to be inherited. The mode of inheritance is not yet well understood, but there are strong indications that it is recessive with incomplete penetrance with some sex-limited involvement.
Treatment of Epilepsy follows two tracks. One is to determine whether there is an environmental factor which may be contributing to the symtpoms, and then attempting to alleviate those factors. The second is to administer anti-epileptic drugs in an attempt to alleviate or lessen the seizures/convulsions. Success in the first endeavor may be frustrating, and you need to carefully consult in detail with your Vet. Commonly admistered drugs include phenobarbital, phenytoin, and primidone, giving the drugs either singularly or in combination.
However, in severe cases, the dog may suffer from convulsions/seizures so involved and continuous (and where medication is minimally effective) that coma or death may result. In unresolvable cases such as these, euthanasia may be the kind and appropriate choice for the animal.
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Adrenal Gland disfunction falls into two types overactive adrenal glands (hyperadrenocorticism - Cushings Disease) and underactive adrenal glands (hypoadrenocorticism - Addison's Disease). Both involve the production of the adrenal hormone - cortisol - one being over production (Cushings), the other being the underproduction (Addison's).
Cushing's Disease is a condition resulting from an excess of adrenal homones (too much cortisol is produced). The onset may be either related to a pituitary tumor (adenoma) in the brain producing ACTH, or by idiopathic hyperactivity of the adrenal gland itself. This condition results in a specturm of functional problems, among those being hair loss and skin lesions (thinning, pigmentation, cutaneous calcium deposition), muscle wasting and/or atrophy, and gradual abdominal enlargement. The disease is insidious, and left untreated may grow progressively worse until systemic shock and death occur.
Addison's Disease is a condition resulting from a deficiency of adrenal hormones (not enough cortisol is produced). The onset of this disease can result from damage to the adrenal glands by infection, cancerous or non-cancerous tumors, drugs, pituitary gland disease or from unknown causes. This condition can result in impaired heart and kidney function, damage to the muscle, reduction in circulating blood volume, and faulty sugar and fat metabolism.
Both diseases are diagnosed with definitive adrenal-function testing which shows the differences that are possible among the causes of the syndromes. You need to consult in detail with your Vet to have the correct diagnostic laboratory assays performed.
General long-term treatment of of Addison's disease involves the administration of fludrocortisone acetate (a corticosteroid). In severe cases, an adrenal crisis is an acute medical emergency and requires prompt Veterinary care to stablize the dog, and prevent shock and imminent death.
Dogs with laboratory confirmed Cushing's disease are treated either surgically or medically depending on the cause. Surgery is indicated in the event of a tumor, to remove the affected gland. Medical drug treatment is indicated in simple idiopathic hyperactivity of the adrenal gland. In both cases, the animal should be monitored in the event that treatment for Cushing's disease induces a low cortisol level which would need to be treated as in Addison's disease.
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Cancer can be a horrible disease. It can devistate the daily life of both the animal and your household.
Cancer is one of the terms given to classes of tumors that are characterized by uncontrolled growth. "Tumor" is the general term for atypical cellular growth, where a mass of cells grow into/displace other cells and organs in the body. Tumors are categorized into two types - benign (basically harmless) and malignant (cancerous).
What is Cancer? -- Cancer is a group of more than 100 different, discreet diseases, each type of cancer being physically and biochemically different than other types in how the cells behave. Cancer occurs when cells become abnormal and keep dividing and forming more cells without control or order. All organs of the body are made up of cells, and normally cells divide to produce more cells only when the body needs them. If cells divide when new ones are not needed, they form a mass of excess tissue, called a tumor. The cells in malignant tumors can invade and damage nearby tissues and organs. Cancer cells can also break away from a malignant tumor and travel through the bloodstream or the lymphatic system to form new tumors in other parts of the body. The spread of cancer is called metastasis.
How is Cancer Diagnosed? -- Cancer is diagnosed by physical examination, radiographs, and tissue samples. The only sure way of confirming cancer is by taking a sample of the suspected tissue, and having it checked by a Pathologist. Samples of tissues may be obtained either by surgical removal of the complete mass or by biopsy of selected portions of tissue by needles or small surgical incisions.
How is Cancer Treated? -- Cancer can be treated with surgery, radiation therapy, chemotherapy, hormone therapy, or biological therapy. The Veterinarian may use one method or a combination of methods. The choice of treatment depends on the type and location of the cancer, whether the disease has spread, the dog's age and general health, and other factors.
Radiation and chemotherapy has shown only limited successes against limited types of cancers, but clinical trials are a constant ongoing process at Veterinary Colleges. Consult with your Veterinarian on the decisions that need to be made regarding the treatment of cancer in your dog. In more complex cases, it is likely that you will be referred to one of the Veterinary Teaching Colleges for a more specialized consultation.
Although the following link is related to human cancer, the American Cancer Society's information on Alternative and Complementary Cancer Therapies is interesting and worthwhile reading.
Is Cancer Genetic? -- Most of the science on whether cancer is genetic or environmental is in the human cancer "model" at the current time. Studies noted in "The Genetics of the Dog" by Malcolm B. Willis clearly indicate an inheritable predisposition exists in dogs, but it stops short of putting a genetic "tag" to which breeders must pay attention.
In the human study of cancer, there are some cancers where there appear to be a very strong viral component in the development of the disease. Also in the human study of cancer, there are some cancers where there appear to be a very strong genetic risk component in family lines. On the research upside: a couple of human malignancy types are starting to "give up" the molecular basis of their cancer, and are being better understood down to the metabolic pathways and DNA coding.
Relatively little molecular biology is being done on canine cancer at this time. Most molecular cancer research is either mouse models or human cell line models. I don't know whether this will change in the future.
Prevalence of Cancer in Dogs? -- Mammary tumors are the most prevalent cancerous condition in dogs, accounting for up to ~50% of tumors found in females (reference Merck Veterinary Manual and "The Genetics of the Dog"). Data clearly indicates that early spay (ovariectomy) reduces the risks to significantly lower levels if the bitch is spayed before sexual maturity (spay prior to first estrus reduces the risk to 0.5% of the risk of intact bitches, while spay after one estrus reduces the risk to 8% of the risk with intact bitches, those spayed after sexual maturity showed no change in risk relative to intact bitches).
-- Bone tumors also present a very large number of cases yearly, with the majority being in large and giant breeds. Several types of bone malignancies, escpecially osteosarcomas, are quite prevalent, and must be treated as soon as possible. Some new advances in chemotherapy and radiation therapy appear to have some promise. Metastisis is common in bone tumors if treated by amputation alone.
-- Canine Lymphoma is one of the most prevalent cancerous conditions in dogs as a whole, affecting all breeds, males and females. It is a malignancy that affects the lymph system, and is progressive, generally being considered as treatable but not curable. Treatment is generally with chemotherapy.
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