The Health of the Giant Schnauzer

 

Based on “The Health of the Giant Schnauzer”, by Cathi Tower

What You Should Know About the Giant Schnauzer, 5^th edition

Published by the Giant Schnauzer Club of America, Inc.  1988.

Revised by C. May-Bowers, 2005.

Click on any link below to refer to that section of the article.

INTRODUCTION

 

ENDOCRINE SYSTEM: 

 

            Addison’s Disease

Cushing’s Disease

            Dwarfism

            Thyroid Gland: 

                        Hyperthyroidism

                        Hypothyroidism

IMMUNE SYSTEM: 

            Autoimmune Disease:

                        Autoimmune Adrenalitis

                        Autoimmune Hemolytic Anemia (AIHA) & Thrombocytopenia

                        Autoimmune Thyroiditis

Non-Neoplastic Enlargement of the Thyroid Gland

 

INTEGUMENTARY SYSTEM: 

 

Allergies:

                        Flea Allergy Dermatitis

                        Atopic

                        Intestinal (Food) Allergies

            Tumors of the Skin and Soft Tissue:

                        Squamous Cell Carcinomas 

 

MUSCULOSKELETAL SYSTEM: 

 

            Cranial Cruciate Ligament & Tibial Plateau Leveling Osteotomy (TPLO)

Elbow Dysplasia:

                        Ununited Anconeal Process

                        Fragmentation of the Medial Coronoid Process

                        Osteochondrosis of the Medial Humeral Condyle

            Hip Dysplasia

Osteochondritis Dissecans (OCD)

Patellar Luxation

 

OPHTHALMOLOGY: 

            Cataracts

            Ectropion

Entropion

Progressive Retinal Atrophy (PRA)

Retinal Dysplasia

URINARY SYSTEM: 

Renal Anomalies

Renal Dysfunction:

            Chronic Kidney Disease

            Acute Kidney Disease

            Urinary Incontinence

 

MISCELLANEOUS: 

            Behavior

Cancer

Squamous Cell Carcinoma

Inflammatory Bowel Disease (IBD)

Methylmalonic Aciduria & Cobalamin Malabsorption (malabsorption of vitamin B12 or Cobalamin)

Pyometra

Seizures & Epilepsy

Symmetrical Lupoid Onychodystrophy (SLO)

            Von Willebrand’s Disease (vWD)

 

REFERENCES: 

 INTRODUCTION

Why are the potential health problems of the Giant Schnauzer so important?  As a potential or current Giant owner, it is prudent to be aware of the possible health issues that this breed faces.  There are known hereditary problems in the Giant Schnauzer and there are problems that have yet to be documented but have appeared in an occasional dog.  Just because a problem has not been widely publicized does NOT mean that it does not occur in the Giant Schnauzer.  One may be able to avoid some of these health related problems by looking for a breeder who screens and tests for known diseases.

If you find that your Giant develops one of these health problems, knowing the possible causes can help you to detect symptoms early enough to seek appropriate treatment while your pet is still in the early stages of the problem.  This knowledge may be able to assist you and your veterinarian to develop a suitable treatment program.  While not all health problems may be genetically transmitted from the parent to the offspring, they have occurred in this breed regardless of the bloodlines of the individual animal.  Some of the listed conditions and diseases are health disorders that all breeds face and are not limited to the Giant Schnauzer.  Giant Schnauzers are susceptible to the same health issues that are known to exist in many breeds.

There are disorders that can be directly linked to genetics and careful breeding practices can reduce their incidence.  However, there are many variables that influence the odds of any one animal developing, being predisposed to, or being a carrier of a specific condition.  It takes multiple generations of occurrence before a definitive link can be established to a bloodline that carries a predisposition to a particular disorder.  Not all dogs that are predisposed to a specific condition will express it.  Mutations, pre- and post-natal influences, and environmental conditions can all contribute to the incidence of occurrence.  These are things that the breeder may not be able to control or predict.  As our knowledge of genetics and DNA and the affordable availability of testing methods increases, so will our knowledge and ability to treat, track, and prevent a specific inherited health condition.

The Giant Schnauzer is registered with the Canine Health Information Center (CHIC) program (http://www.caninehealthinfo.org/).  This is a centralized canine health database jointly sponsored by the American Kennel Club/Canine Health Foundation (AKC/CHF) and the Orthopedic Foundation for Animals (OFA).  Its purpose is to provide a source of health information for owners, breeders, and scientists that will assist in breeding healthy dogs.  The Giant Schnauzer Club of America (GSCA) encourages breeders and owners to participate in this program.  For people who are interested in owning a Giant Schnauzer we strongly recommend looking for a breeder who has the following health tests and certifications on their dogs:  OFA or Penn-Hip for hips and elbows, CERF for eyes and Thyroid panels which are both performed periodically. 

Giant Schnauzer Club of America encourages breeders to microchip their litters and register their dogs with the AKC DNA registry.  This will help to insure accurate and precise health data for the healthy future of the Giant Schnauzer breed.

ADDISON’S/CUSHING’S DISEASE:  These are endocrine or hormonal disorders involving the adrenal and pituitary glands. 

Addison’s Disease (hypoadrenocorticism):  A deficiency in the adrenocortical hormones and it is seen most commonly in young to middle-aged dogs.  The cause of primary adrenocortical failure usually is not known, although it can be related to an autoimmune process, the destruction of the adrenal gland by granulomatous disease, metastatic tumors, hemorrhage, infarction, or an overdose of mitotane.  Symptoms may not be specific and they may include recurrent episodes of gastroenteritis, a slow and progressive loss of body condition, weight loss, diarrhea, vomiting, and a failure to respond appropriately to stress.  A helpful diagnostic clue is if the dog has vomiting and diarrhea constantly after a stressful episode like showing, boarding, or breeding.  Acute circulatory collapse and evidence of renal failure frequently occur if the disease is not treated.  When successfully diagnosed, the condition can be easily managed.

Cushing’s Disease (hyperadrenocorticism):  A chronic excess of adrenocortical hormones from the adrenal gland, which is also frequently encountered disease in adult to senior dogs.  The most common cause is a pituitary-dependent hyperadrenocorticism, which commonly is a result of a benign tumor in the pituitary gland.  Symptoms can range from an increase in water consumption and urination, heat intolerance, lethargy, abdominal enlargement (potbelly), panting, obesity, muscle weakness, and recurrent urinary tract infections.  There are also numerous skin symptoms, such as, loss of hair on the belly area, thin skin, acne-like skin bumps, bruising, changes in skin pigmentation, deposits of calcium in the skin, skin infections, secondary red mange, and seborrhea.  Diagnosis of Cushing’s Disease requires specific ACTH stimulation or Dexamethasone Suppression testing.  Periodic ACTH stimulation testing is typically used to monitor the endogenous plasma ACTH concentrations in the dogs system can assist in treatment and to detect a variety of adrenopathic disorders.  Although this condition takes close monitoring to control, a new treatment is now available.  While not yet FDA approved, Trilostane has been used in Europe for many years, and can be obtained in the USA by veterinary internists.  It is safer to use in older dogs.

DWARFISM:  This is a disease that is associated with the Pituitary Gland.  It is characterized by shortening and thickening of long bones, most commonly the forelegs.  This is an inherited autosomal recessive trait.  Mildly affected dogs may appear clinically normal, though radiographs will show changes in the bones as early as 4 weeks.  There are several types of dwarfism and blood tests can detect affected dogs at a very young age.  Pedigree studies are being done to trace carriers and affected pups.  A carrier may not show any signs of this problem but will pass it on if bred.

THYROID DYSFUNCTION:  The Orthopedic Foundation for Animals (OFA) has a Thyroid Certification program (http://www.offa.org/thyinfo.html), which can identify dogs over 12 months have FT₄D, cTSH, and TgAA that are within normal range.  Autoimmune thyroiditis is the most common cause of primary hypothyroidism in dogs and is recognized as a heritable condition. Predisposed dogs are born with normal thyroid function and generally grow and develop in a normal manner.  Evidence of an immune reaction in the thyroid glands begins to appear sometime in early adulthood in the majority of affected dogs. The initiating factors remain unknown, but part of the response is the appearance of thyroid autoantibodies directed at thyroglobulin and sometimes the thyroid hormones, T₄ and/or T₃. Eventually the autoimmune response results in irreversible destruction of the thyroid glands, an inability to make thyroid hormones, and finally, development of clinical signs of hypothyroidism. This pathologic process may extend for several years in many affected dogs. Thus detection of positive thyroid autoantibodies early in the course of the disease serves to identify dogs at increased risk of becoming hypothyroid in the future.  Because of the variable onset of the presence of autoantibodies, periodic testing is recommended.

Hypothyroidism:  This is probably the most common form of thyroid dysfunction observed in Giants along with many other breeds.  Dogs afflicted with hypothyroidism have an impaired production and secretion of the thyroid hormones which results in a decreased metabolic rate.  The common cause of thyroid hormone deficiency is as a result of the destruction of the thyroid gland itself.  There are two common causes of adult primary hypothyroidism are lymphocytic thyroiditis and idiopathic atrophy of the thyroid gland.  Secondary hypothyroidism is commonly due to a growing tumor that destroys the pituitary thyrotrophs.  Congenital secondary hypothyroidism has been noted to occur in rare cases in the Giant Schnauzer, this form is associated with symptoms of disproportionate dwarfism, lethargy, gait abnormalities, and constipation.  

Hypothyroidism is most commonly seen in dogs between 4-10 years of age.  Because a deficiency of thyroid hormone will affect the function of all organ systems the symptoms can be varied or non-specific.   Symptoms may include mental dullness, lethargy, intolerance of exercise, weight gain without a gain in appetite, mild to marked obesity, low body temperature causing the dog to seek heat.  Coat and skin problems can include dryness, excessive shedding, retarded hair growth (in early stages), thinning hair or alopecia typically appears on both sides of the trunk, back of the thighs, top of the tail, lower side of the neck, and/or top of the nose.  Thickening of the skin resulting in a puffy appearance of the forehead and face along with slight drooping of the upper eyelid.  Hypothyroidism can disrupt the reproduction functions.  In females this can cause failure or sporadic cycling, infertility, abortion, or poor litter survival.  Males may experience lack of libido, testicular atrophy, hypospermia, or infertility.

Thyroxine (T₄) is the thyroid hormone replacement compound most commonly used in dogs for treatment.  Replacement therapy is usually necessary for the remainder of the dog’s life and periodic monitoring to adjust the required dosage may be necessary.  Improvement in condition typically can be noted after 1-2 months of therapy.  Failure to improve can be due to incorrect dosage, the animal’s inability to absorb the product, or there was an incorrect diagnosis.

Hypothyroidism is one of the most over and under diagnosed diseases and many diseases can mimic or be misdiagnosed as hypothyroidism.  Some of these symptoms do respond to the medications used to treat this condition. 

Hyperthyroidism:  Is an excessive secretion of the thyroid hormones T₃ and T₄, which results in symptoms that reflect an increased metabolic rate.  This is not a commonly seen condition in dogs and thyroid carcinoma is the primary cause.  The typical symptoms are weight loss, increased appetite, hyperexcitability, increased thirst and frequency of urinating, noticeable enlargement of the thyroid gland.  These symptoms may also include vomiting, diarrhea, and increased fecal volume.  Heart problems may be associated with hyperthyroidism.  As with hypothyroidism an ongoing treatment therapy will be required throughout the remainder of the dog’s life.  

 Non-Neoplastic Enlargement of the Thyroid Gland (Goiter): Can be a result of iodine deficiency, goitrogenic substances, dietary iodine excess, and inherited enzyme defects in the biosynthesis of thyroid hormones. Some animals with goiter can display clinical signs of hypothyroidism. Insufficient iodine reduces the ability of the thyroid to make thyroid hormone. The hyperplastic gland may compensate for the reduced availability of iodine and the animal may not have clinical signs of hypothyroidism. However, animals born to females on iodine deficient diets are more likely to develop sever thyroid enlargement and have clinical signs of hypothyroidism.  

AUTOIMMUNE DISEASE:  Is a disease process that involves the production of host antibodies to the host tissue.  Blood tests can involve leukocyte count, globulin profile; Igm, IgA, IgG levels; complement level, Cell Immunophenotyping, and Antibody Response to Vaccination.

Autoimmune Adrenalitis:  This disease involves cell-mediated immunity where the adrenal glands are slowly destroyed by a plasmacytic-lymphocytic infiltrate.  When sufficient glandular tissue is destroyed, the dogs develop Addison’s syndrome.  It can be associated with similar immune attacks against other endocrine glands, such as the thyroid. 

Autoimmune Hemolytic Anemia (AIHA) & Thrombocytopenia:  The antibody and complement attach to the red blood cells either directly or indirectly via an absorbed antigen and mediate red blood cell destruction resulting in severe, life-threatening anemia.  Drugs, vaccines, or infections can precipitate attacks, however more often than not, the trigger is unknown.  There are four basic forms of this Type II immunopathologic disease:  peracute (seen in middle-aged large breeds), acute or subacute (most common form), chronic, and pure red cell aplasia.  Thrombocytopenia can affect all dog breeds and tends to occur more often in females than males.  Decrease in the number of blood platelets and is associated with hemorrhagic conditions.  Hemorrhages of the skin and mucous membranes may be accompanied with dark tarry stools containing decomposing blood, nose bleeding, or blood in the urine. 

Autoimmune Thyroiditis:  This disease involves cell-mediated immunity and is characterized by the destruction of the thyroid gland by an autoimmune process that has both humoral and cell-mediated components.  Hypothyroidism may be the sole manifestation of the disease or a component of this disease. 

INTEGUMENTARY SYSTEM:  Involves diseases and disorders related to the skin membrane.  These can include congenital and inherited anomalies, allergies, bacterial viral, fungal, and parasitic skin diseases, or tumors.

 

Allergies:

                        Flea Allergy Dermatitis

                        Atopic

                        Intestinal (Food) Allergies

            Tumors of the Skin and Soft Tissue:

                        Squamous Cell Carcinomas 

ALLERGIES:  Canine allergies can be triggered by a wide variety of stimulants and an allergic reaction can occur at any point in the animal’s life time.  The typical allergy results in a physical reaction to an allergen.  This reaction can range from mild to severe symptoms.  Atopic allergies typically affect the feet, face, and chest or belly area.  Flea allergies can affect the back, lower back, tail bone, and hind legs areas.  Food allergies can affect the ears, feet, groin, armpits, forelegs, surrounding the eye socket, and muzzle. 

Flea Allergy Dermatitis (FAD):  Typically a reaction to the flea’s saliva and result in severe itching and chewing.  Classic clinical signs are lesions distributed on the lower back, tail head, and posterior and inner thighs.  Restlessness, discomfort, scratching, licking, chewing and nibbling at the skin are common reactions.  The hair may be stained brown and broken off from the licking. Heavy infestation can cause iron deficiency anemia or disease transmission.  The monthly flea products Advantage and Frontline have made control of FAD simpler and les toxic than in the past.

Atopic Dermatitis:  This is an itch producing chronic skin disorder which can often be caused by inhaled allergens or absorption of the allergen through the skin.  The dog’s immune system may be hypersensitive to common substances in the environment, such as dust mites or molds.  Dogs with a chronic condition may have pinkish, to angry red, to black mottling areas on the abdomen skin.  Atopic dogs often chew at their feet and armpits, excessive sweating can be noted in the hairless areas.   Other common symptoms are scratching, biting, chewing at feet, constant licking, face rubbing, or ear infections.   

Intestinal (Food) Allergies:  Allergic gastritis is associated with a mild inflammation of the small intestine.  Symptoms can include but are not limited to vomiting, loss of weight, loss of coat condition, body odor, skin lesions, diarrhea, or bloody feces, flatulence, sneezing, asthma like symptoms, head shaking, ear infections, anal itching, behavioral changes, or seizures.  Food allergies may also mimic atopic or flea allergies.  A 6-8 week food trial on a hypoallergenic diet is the only way to diagnose a food allergy, along with ruling out other concurrent allergies. 

TUMORS OF THE SKIN AND SOFT TISSUE:  Skin tumors are common in domestic animals and are typically easy to identify.  Chemical carcinogens, ionizing radiation, and viruses, hormonal, or genetic factors can contribute to the development of abnormal skin growths. 

Squamous Cell Carcinoma:  This is known to occur in dark haired dog breeds, including the Giant and Standard Schnauzers.  It has been associated with the development of subungual squamous cell carcinomas (scaly or plate-like tumors beneath the nail) on multiple toes and can often be found on different extremities.  The first symptoms are typically lameness or malformation, an infection that mimics chronic bone inflammation (osteomyelitis), or loss of a nail on the affected toe.  Squamous cell carcinomas tend to invade into adjacent soft and bony tissues.  Well-differentiated tumors tend to remain localized and slow to progress, while undifferentiated tumors are more likely to spread.  This indicates that quick diagnosis and removal of the infected toe(s) can increase the likelihood of survival.  Once this cancer spreads into the dog’s chest cavity chances of successful treatment are low. 

MUSCULOSKELETAL SYSTEM:  Consisting of the bones, cartilage, muscles, ligaments and tendons.

 

            Cranial Cruciate Ligament & Tibial Plateau Leveling Osteotomy (TPLO)

Elbow Dysplasia:

                        Ununited Anconeal Process

                        Fragmentation of the Medial Coronoid Process

                        Osteochondrosis of the Medial Humeral Condyle

            Hip Dysplasia

Osteochondritis Dissecans (OCD)

Patellar Luxation

CRANIAL CRUCIATE LIGAMENT & TIBIAL PLATEAU LEVELING OSTEOTOMY (TPLO):  This is a common leg injury in large and active dog breeds and typically is a gradual process, rather than due to a single traumatic injury. The cruciate ligament prevents forward and backward sliding of the femur on the tibia bone and is responsible for maintaining a stable stifle joint.  This condition occurs when the ligament is torn and the result is lameness.  TPLO surgery can be performed if it does not heal on its own.  If a dog is overweight it can impede the healing process.  Recovery time is approximately 6-8 weeks, and the hips should be screened before any stifle surgery is pursued.

ELBOW DYSPLASIA:  The Orthopedic Foundation for Animals (O.F.A. http://www.offa.org/ ) gives certificates for dogs physically free from elbow dysplasia.  Elbow dysplasia can be related to abnormal bone growth, joint stress, or cartilage development in young, large, rapidly growing dogs.  Most elbow dysplasias occur in the first 6-9 months.  A slight limp or exercise intolerance may be noted, but often no symptoms are present until arthritis occurs months later.  There are three basic forms:  

Ununited Anconeal Process:  Affects dogs between 4 to 8 months and can result in lameness or restricted range of motion. 

Fragmentation of the Medial Coronoid Process:  A condition where the coronoid process fails to unite either partially or totally, resulting in joint laxity, irritation, and osteoarthritis. 

Osteochondrosis of the Medial Humeral Condyle:  There is a disturbance in the endochondral fusion of the epiphysis of the medial epicondyle with the distal end of the humerus.  Pain when the elbow is bent or deeply palpated, soft-tissue swelling may be noted. 

Surgery is the primary treatment and provides the best results if performed early.  Surgical specialty practices can now use endoscopic surgery for elbow dysplasias.  Because endoscopic surgery is less invasive, time of recovery is reduced.  If elbow dysplasia is allowed to go untreated then secondary problems such as osteoarthritis and degenerative joint disease can develop.                       

HIP DYSPLASIA:  The Orthopedic Foundation for Animals (O.F.A. http://www.offa.org/ ) and the University of Pennsylvania Hip Improvement Program (PennHIP http://www.pennhip.org/ ) gives certificates for dogs physically free from hip dysplasia.   

In hip dysplasia, the fit of the joint is loose, and the harmony of joint movement is disturbed.  The looseness is demonstrated on x-rays as a separation of the head of the femur from the acetabulum (subluxation).  The result of separation is a widening of the joint space, stress on the joint attachments and or a shallowness of the acetabulum.  The hip reacts by changes in bone size, shape and structure (remodeling), changes in the articular cartilage and in the synovial fluid.  The end result is a form of arthritis called osteoarthritis or degenerative joint disease.  There are all degrees of change ranging from minimal subluxation, to severe bone reaction, to severe osteoarthritis. 

The dysplastic dog thus has a weakened structural foundation.  The weakness, depending on the individual dog and degree of joint damage, may be readily detected or may avoid detection for some period of time.  Observation of the dysplastic dog’s movement may reveal all stages from normal to a crippled animal.  Symptoms of pain or discomfort also vary with the stage of development.  They are usually classified as the acute phase (3 to 2 months of age) or the chronic phase (arthritic symptoms in the mature dog).  Severity of the symptoms depends on how well the individual adjusts to the problem and the type of environment in which the dog lives.

Hip dysplasia is an inherited trait.  It is controlled by the genetic makeup (genotype) of the individual dog.  The genotype is determined by the genes received from the parents.  The current concept is: hip dysplasia is a polygenic trait.  That is, many genes affect the trait of dysplasia. Affected dogs should not be used for breeding purposes. Affected females should be spayed and males neutered.  With sensible care, many dysplasia-affected dogs can live reasonably normal lives as companion animals. 

Studies in the last 5 years have demonstrated that large-breed puppies that are kept lean develop up to 60% less hip dysplasia than puppies that are allowed to free-feed. The current recommendation is to stop feeding puppy formulas at 6 months of age, keep the pups at a lean body mass, and not add any supplements.  Bone growth is not complete until about 2 years of age, and allowing bone structure to mature before muscle mass grows reduces hip dysplasia.

OSTEOCHONDRITIS DISSECANS (OCD):  OCD is a developmental disease that usually affects rapidly growing medium, large, and giant breed dogs from 4 to 10 months.  It affects the immature joint and is characterized by local fracture of articular cartilage which may lead to formation of a cartilage flap or joint mouse.  It can occur in the following joints: shoulder, elbow, stifle, and hock.  The dog will typically show a sudden onset of pain which does not dissipate, either with medication or enforced rest.  Shoulders, elbows, stifles and hocks can be affected with the shoulders being the most prevalent.  OCD can be caused by trauma, rapid growth, excessive nutrition, ischemia (obstruction of blood supply to the area), and hereditary abnormalities of ossification (bone formation).  Research shows that overnutrition leads to overgrowth before the skeleton is mature enough to handle weight and stress.  In other words, animals forced nutritionally tend to have a higher incidence of these lesions.  There may be some genetic predisposition for a rapidly growing individual of a breed.  Surgery can remove the cartilage flaps or free floating fragments or stimulate the fibrocartilage formation.

PATELLAR LUXATION:  This is a hereditary disorder in dogs and is characterized by an abnormal development of the lateral to the trochlear groove of the femur in large dog breeds.  It can be associated with multiple deformities of the hind limb, associated with the hip joint, femur and tibia.  It can affect dogs of any age and the symptoms typically lameness or walk with a skipping gait.  Depending on the severity of the problem the common treatment is surgery. 

OPHTHALMOLOGY:  Involves conditions and diseases of the eye, eyelid, and the area around the eye.

 

            Cataracts

            Ectropion

Entropion

Progressive Retinal Atrophy (PRA)

Retinal Dysplasia

EYE DISEASE:  The Canine Eye Registration Foundation (C.E.R.F.) is an organization that maintains a national registry and certification program, certifying that a dog is free of heritable eye disease after being examined by an American College of Veterinary Ophthalmologist (A.C.V.O.).   http://www.vmdb.org/history.html

Cataracts:  Notable by the opacity of the lens of the eye or of its capsule.  Cataracts are classified by their age of onset (juvenile, senile, or congenital), anatomic location, cause, degree of opacificaion, and shape.  They can be inherited or caused by age, diabetes mellitus, malnutrition, radiation, inflammation, and trauma.  Typically they can be treated by surgery and have the best results if when performed before the cataract maturation is complete. 

Ectropion:  A slack, outward turning lid margin, usually with a large fissure or cleft near the eyelid.  This is a common bilateral conformational abnormality in a number of dog breeds and can also occur with contracting scars in the lid or with facial nerve paralysis.  Exposure to environmental irritants and secondary bacterial infection can cause chronic or recurrent conjunctivitis.  This condition can be treated surgically or in mild cases control of related intermittent infections can be treated without surgery.    

Entropion:  An inversion of all or part of the eye lid margins and may involve both eyelids and the where the upper and lower eyelid meet.  This is an inherited defect and it may also follow cicatrix formation (a scar left by a healing wound that can appear contracted) or severe spasmodic winking from involuntary contraction of the muscle of the eyelids due to surrounding eye area or eye pain.  Without surgical treatment this condition may cause discomfort, conjunctival and corneal irritation, corneal scarring, pigmentation, and possibly ulceration.

Progressive Retinal Atrophy (PRA):  This is a group of degenerative noninflammatory disorders of the retina consisting of inherited photoreceptor dysplasia and degenerations that have similar appearance.  Night blindness is noted early and progresses to total blindness over time.  Cortical cataracts are common late in the course of PRA and may mask the underlying retinopathy.  Blood and buccal mucosa-based DNA markers and specific gene tests have been developed to detect carrier and affected dogs before signs of development.  Dogs with PRA move with caution, bump into objects, initially show defective vision at night or dusk.  Owners may note pupil dilation before day vision is lost.  The pupils then dilate totally as there is no response to light stimuli.  The rate of progression varies with individuals, from a matter of weeks to 6-9 months.  It appears that in most cases the dogs affected early in life progress to blindness more rapidly than those which show first signs at an older age.  Peripheral vision is lost initially, but this may go unnoticed by the owner, then the central vision disappears rapidly and the dog’s ability to see immediate objects is lost. 

Retinal Dysplasia:  Is a congenital, focal, geographic, or generalized maldevelopment of the retina that may arise from trauma, genetic defect, or intrauterine damages, such as viral infections.  Most forms are inherited.  Focal areas of retinal maldevelopment may have no symptoms of this disease or it may interfere with the dog’s central vision.  There are three forms:  Folding of one or more areas of the retina (this is the mildest form and may not affect vision), geographic (folding and disorganization of the retina), and detached (severe disorganization associated with separation of the retina).  Some loss of vision or blindness is associated with geographic or detached forms. 

URINARY SYSTEM:  The urinary system includes the excretion of waste products of metabolism, utilization of water and electrolytes, production of hormones which regulate blood pressure and sodium absorption, metabolism of vitamin D to its active form.  Changes in water consumption, urine characteristics (odor, color, volume, and/or frequency) and behavior may be related to urinary system problems.  Urinalysis is one of the primary tools for diagnoses of many medical conditions.

 

Renal Anomalies

Renal Dysfunction:

            Chronic Kidney Disease

            Acute Kidney Disease

            Urinary Incontinence      

RENAL ANOMALIES:  Typically are congenital and inherited anomalies.  Renal Dysplasia and Hypoplasia are defects which can be either unilateral or bilateral and the kidneys are usually small, firm, and pale.  Affected dogs usually show an increase in thirst and urination.  Treatment involves managing the associated chronic renal failure. 

RENAL DYSFUNCTION:  A failure of the filtration function of the kidneys.   

Chronic Kidney Disease:  This disease involves the loss of functional renal tissue due to prolonged and progressive process.  An affected dog may not show symptoms initially and it is invariably irreversible and progressive condition.  It typically is observed in animals between 5-6 years of age and will affect 10% of all breeds of geriatric dogs.  Treatment will depend on the stage of advancement of the disease. 

Acute Kidney Disease:  Occurs typically when sudden and major injury damages the kidneys.  The common causes are toxins (such as, ethylene glycol, aminoglycoside antibiotics, hypercalcemia, or hemoglobinuria) or a temporary deficiency of blood flow to the kidneys.  Repeated bouts of mild or acute kidney disease may lead to chronic kidney disease.  Symptoms can include anorexia, depression, dehydration, oral ulceration, vomiting and/or diarrhea, or a reduced urine volume.  Treatment will depend on the cause.  

An old disease making a comeback in Northern California is Leptospirosis.  Lepto is caused by a bacteria that can be transmitted in water contaminated with raccoon or cow urine.  It can lead to acute renal failure and death if not diagnosed and treated immediately.  The common DHLPP vaccine does not contain the serovar types that are currently causing disease.  A new vaccine containing the distinct serovars is now available, and can be given to animals at risk.

 

Ingestion of antifreeze can also lead to irreversible renal failure. 

URINARY INCONTINENCE:  Urinary Incontinence refers to the inability of the bladder to store urine and can affect both dogs and bitches.  This is a common problem in large breed, spayed female dogs with an 11-20% chance of occurring after spaying.  However, leaking can also occur in intact females and male dogs. Urinary incontinence can also occur due to an anatomical malformation of the lower urinary tract.  Symptoms range from slight to constant or heavy dripping, wet spots where the dog has been sitting or laying, the dog urinates without squatting or lifting its leg.  Stress or other health problems can contribute to this problem.   

Dogs that experience urinary incontinence have little to no control over their bladders and the owners may mistakenly think they the dog is not responding to normal housebreaking methods.  Treatment can range from using nonsteroidal estrogen (DES) for females, testosterone for males, phenylpropanolamine (PPA), or surgery if the cause is due to a correctable malformation.  Doggie bloomer or diapers, baby bed pads, and other product available through most pet stores can improve the relationship between the leaking dog and the owner. Young dogs exhibiting incontinence should have urinary tract infection ruled out, then an anatomical abnormality should be suspected. 

Juhen incontinence:  Results from urethral sphincter tone (sphincter incompetence) and can occur in spayed and neutered dogs.  There are two basic neuromuscular components.  One involves the muscular contraction and relaxation of the bladder wall, while the other controls the muscular sphincters in the urethra.  This condition can be treated with alpha agonist drugs (such as phenylpropanolamine, PPA), which will stimulate the neuromuscular receptors of the urethral muscles.  Estrogen therapy can also be used; however there are greater chances of adverse side effects.  

Ectopic ureter:  A congenital malformation, which may be inherited.  The ureters normally carry urine from the kidney to the bladder; however, ectopic ureters may be connected to an abnormal location in the lower urinary tract causing the dog to dribble uncontrollably.  Surgery has been the traditional treatment for this form of urinary incontinence. 

There are diseases such as hyperadrenocorticism, diabetes mellitus, kidney failure, hypercalcemia, Cushing’s Disease, bladder cancer, and liver disease which can cause increase urine production and should be considered for proper treatment.   

MISC: 

 

            Behavior

Cancer

Inflammatory Bowel Disease (IBD)

Methylmalonic Aciduria & Cobalamin Malabsorption (malabsorption of vitamin B12 or Cobalamin)

Pyometra

Seizures & Epilepsy

Symmetrical Lupoid Onychodystrophy (SLO)

            Von Willebrand’s Disease (vWD) 

BEHAVIOR:  Between 3-8 weeks of age dogs tend to focus on other dogs for their social stimuli.  Between 5-12 weeks they will start to focus on people.  They are most receptive to learning how to deal with new experiences, environment, and stimuli up to 16-20 weeks of age.  Afterward this age dogs are slower to learn from exposure and may process what they learn differently.  If not socialize with people before 14 weeks of age many dogs may have undeveloped social skills.  Large breeds reach their sexual maturity between 12-36 months.  At this point the established social hierarchy in the household may change.  This is the stage where dog-on-dog aggression may occur in multiple dog households.  Fighting, roaming, intra-sexual fighting, marking, mounting are facilitated by sex hormones and these behaviors can be reduced by neutering or spaying. 

Aggression is the most common behavioral problem and can be associated with the following types of aggression: dominance or impulse control, fear, anxiety, food or resource related, idiopathic or unpredictable aggression, intradog (same sex), maternal, pain, play, possessive, predatory, protective, redirected, or territorial aggression.  Sudden aggression can also be due to a result of an infection, toxicity, or an atypical drug response.   

Many health problems and medications can alter a dog’s behavior.  If there are sudden changes in a dog’s personality, habits, sudden displays of unusual aggression or temperament problems, inappropriate elimination or urination, reduced drive or lack of interest, shyness, compulsive behavior, or odd reactions to normal events in normally steady dogs it is advisable to consult a veterinarian concerning an underlying health issue which may be contributing to the behavior change.  Some recognized causes of behavior changes in dogs are pain, discomfort, dental problems, old age, neurological problems, chemical imbalances, and disease. 

CANCER:  Malignant neoplasia is marked by an uncontrolled growth of cells which often invade healthy tissues either locally or throughout the body.  Carcinomas are cancers that arise from epithelial tissues, sarcomas from the mesenchymal tissues, lymphomas from the lymphatic cells, and leukemias from the blood forming cells.  Many cancers and tumors seen in Giant Schnauzers are common to many large bodied dog breeds.  Symptoms and treatments will vary on the type, stage, and health of the individual dog. 

INFLAMMATORY BOWEL DISEASE (IBD):  This is a gastrointestinal disease of unknown etiology and comes in a variety of forms classified by the afflicted location in the body.  Symptoms can be either chronic or cyclical and may involve vomiting, diarrhea, changes in appetite, and weight loss.  The appropriate treatment should address the initial cause which may be due to dietary, parasitic, bacterial overgrowth, or drug reactions.  Treatment typically involves dietary modifications or the appropriate medication.  It should be noted that Inflammatory Bowel Disease is not the same as Irritable Bowel Syndrome (IBS) which is a stress-related diarrhea problem.  With cases of IBS the treatment is aimed at the cause or ability to cope with stress. 

METHYLMALONIC ACIDURIA & COBALAMIN MALABSORPTION (malabsorption of vitamin B12 or Cobalamin):  This is a condition where there is a deficiency of Cobalamin or Vitamin B12 which is necessary for a variety of enzyme reactions.  The result is an accumulation of methylmalonic acid and impaired cellular proliferation and maturation resulting in anemia, leucopenia, and thrombocytopenia.  While this is an inherited disease which typically affects puppies, it can also be acquired by older dogs that have experienced malnutrition, malabsorption, exocrine pancreatic insufficiency, or bacterial overgrowth of the small intestine. Symptoms can include failure to thrive or gain weight, lack of appetite, vomiting, lethargy, abnormal behaviors, and seizures.  Treatment is typically in the form of vitamin B12 supplements or injections. 

The Orthopedic Foundation (http://www.offa.org/dnatest.html) and  the University of Pennsylvania: School of Veterinary Medicine’s Department of Clinical Studies has a Metabolic Screening Submission Form available for Giant owners who wish to participate in their study:  http://w3.vet.upenn.edu/research/centers/penngen/services/metaboliclab/methylmalonic.html. A urine sample is required with the application.   

PYOMETRA:  This condition which typically affects bitches over 5 years, 4-6 weeks after estrus.  The uterus is typically abscessed and filled with pus by a secondary infection.  The primary cause is a hormonally mediated diestrual disorder.  If left untreated bacteria and toxins can leak across the uterine walls and into the bloodstream which can be fatal.  Symptoms can include lethargy, anorexia, increased thirst, increased urination, and vomiting.  A vulvar discharge, often containing blood, may be observed when the cervix is open but may not be observed when cervix is closed.  An enlarged large uterus may cause abdominal swelling.  This condition can progress rapidly from shock to death.  Treatment will typically involve the removal of the ovaries and uterus.  Hormone therapy may be used as an alternative depending on the severity and progression of this condition. 

SYMMETRICAL LUPOID ONYCHODYSTROPHY (SLO):  SLO is a disease which affects the dog’s nails or claws, it typically involve multiple nails and may occur on more than one foot.  It does not seem to be contagious and the age of onset is usually between 1 to 6 years.  “Symmetrical” indicates that more then one foot is involved, “oncychomadesis” refers to the loss of the nail, and “lupoid” is used to describe microscopic changes of affected nails.  The underlying etiology is unknown however it is thought to be immune mediated.  The typical symptoms of SLO are nails that fall off, are soft, friable, or hollow.  A secondary infection may be accompanied by a strong smell, nail splitting, pained, distorted or twisted nails, and lameness.  After successful treatment the nails may continue to grow out deformed due to damage to the nail bed, this does not indicate a reoccurrence of SLO.  The typical treatment is antibiotics and high doses of fatty acids over a period of several months to life depending on the form and severity of the infection.           

SEIZURES: Seizures are an indication of abnormal brain activity, manifested by one or more symptoms, such as stiffening, loss of consciousness, urination, salivation, muscle tremors, paddling motion of the feet, whining, disorientation, or other behavioral changes.  The seizure may last from a few seconds to several minutes.  If longer, or of a rapid repetition, it could indicate a medical emergency. Seizures may be caused by infections, metabolic imbalances, trauma, toxins, tumors, congenital defects (inherited) or other unknown causes.  The most common toxin associated with seizures is snail bait.  Snail baits have a very attractive sweet taste to dogs, and should be stored in closed cabinets, and not used where dogs are present.  “Sluggo” is a non-toxic form of snail bait now available.  Seizures may be symptoms of other illnesses or the illness of epilepsy itself.  Following a seizure the dog may appear disorientated or blind which may last a few minutes or several hours.  If the dog faints it will usually seem normal within seconds of the faint.  There are several categories of seizures: 

The age of the dog may assist in indicating the cause of the seizure.  Dogs under 1 year of age can experience seizures caused by infections of the brain.  Dogs between 1 and 5 years will often be diagnosed with epilepsy (seizure disorder) if they experience repeated episodes.  Dogs above 5 years can experience tumor induced episodes, where there is a tumor growing off of the skull and is pressing on the brain (meningioma).  There are three types of observed seizures:  Reactive Seizures which typically result from metabolic problems or toxicity and the brain function is normal; Secondary Seizures where brain abnormalities are the origin of this type of seizure; and Primary Seizures which are neither reactive or secondary seizures.  If a dog experiences a seizure non-stop for more than five minutes or has more then 3 episodes within a 24 hour period this should be considered an emergency.

EPILEPSY:  While the genetic base is not understood, when the seizures occur between 1 and 5 years of age the major cause is epilepsy.  In order for this diagnosis to be confirmed the dog must have had more than one seizure episode.  If the cause is not traced to another source it is defined as epilepsy.  Once seizures are present the tendency to have another at some future time is always present.  If the seizure is an indication of a specific illness a specific treatment can be given.  If it is epilepsy it can only be treated with anticonvulsant drugs.  There are several available and may be prescribed singly or in combination while potential side effects are monitored.  Only about 65% of affected dogs can be controlled by medication.  Control is defined as a decrease in, but not a permanent absence of seizures. 

As the genetic background is yet undocumented it is especially imperative that an affected animal not be used for breeding.  Bitches should be spayed and dogs neutered to lessen the effect of hormonal changes which might trigger seizures.  Some dogs have lived somewhat normal lives for several years on regular medication, but the prognosis is not good. 

• The Epilepsy Genetic Research Project (www.canine-epilepsy.net/cerc.html):  Veterinary Neurologists at several universities are looking for a genetic answer to epilepsy. They seek DNA samples from epileptic dogs and their close relatives if possible.

• Canine Epilepsy Network (www.canine-epilepsy.net/basics/basics_main.html):  Affiliated with the Veterinary School at the University of Missouri at Columbia, this site reviews canine seizure disorders, treatment, history and more.

• Epil-K9 (http://www.canine-epilepsy.com/subscribe.html): A support and news group for owners of seizuring dogs. The group has a substantial library of useful resources.

• The Epi Guardian Angels (http://www.canine-epilepsy-guardian-angels.com/):  A support group for owners of epileptic dogs.

VON WILLEBRAND’S DISEASE (vWD):  Von Willebrand’s Disease is the most common, mild inherited bleeding disorder of man and animals.  It is an autosomal recessive or autosomal, incompletely dominant trait.  A clinically affected dog can have mild to severe bleeding from gums or genitals, or following surgical procedures will bleed excessively.  Affected pups will bleed excessively from the umbilical cord at birth or after tail docking or ear cropping.  There is thought to be a casual relationship between hypothyroidism and vWD, as several breeds which are now recognized to have a high prevalence of hypothyroidism also commonly have vWD (Doberman Pinchers, Golden Retrievers, Scottish Terriers, Corgis, and Manchester Terriers), however it can also occur in any breed or mixed breed dog.  VWD carriers might test normal while on thyroid medications and can preclude the accurate diagnosis of the carrier’s genetic status for the disorder.  A simple blood test done once in a dog’s lifetime can test for this anomaly. 

 

REFERENCES: 

 “The Health of the Giant Schnauzer” from What You Should Know About the Giant Schnauzer, 5^th edition.  Published by the Giant Schnauzer Club of America, Inc.  1988.  http://www.giantschnauzerclubofamerica.com/

Behavior Problems in Geriatric Dogs, by Wayne Hunthausen, DMV.  2005. http://www.westwoodanimalhospital.com/BhvArticles/GeriatDogBhvProb.htm

The Canine Eye Registration Foundation C.E.R.F.:   National registry and certification program, certifying that a dog is free of heritable eye disease after being examined by an American College of Veterinary Ophthalmologist (A.C.V.O.).  2005.

http://www.vmdb.org/history.html

The VMDB/CERF Offices are located on the campus of Purdue University:

For matters related to the Canine Eye Registry Foundation, CERF exams and CERF certifications: CERF@vmdb.org

For general information about the Veterinary Medical DataBases: vmdb@vmdb.org

Canine Health Information Center (CHIC):  Dogs who have both OFA database listings and CHIC certifications are now cross-referenced from the OFA site. Dogs with a CHIC number will be listed in the OFA database with the CHIC logo, which will be linked to their information in the CHIC database. This will help breeders and owners using both sites find health data on dogs.  2005.

http://www.caninehealthinfo.org/chicnumbers.html

El Sobrante Veterinarian Hospital

Patricia Bacchetti, D.V.M.

Kathleen Brennan, D.V.M.

Health Links.  2005.  http://www.thuntek.net/~jrgeilo/health_links.htm

IVIS. 2005.  http://www.ivis.org/

Mar Vista Animal Medical Center. 2005.  http://www.marvistavet.com/index.html

Merck Veterinary Manual, Ninth Edition.  Editor:  Cynthia M. Kahn, B.A, MA.  Associate Editor:  Scott Line, D.V.M., Ph.D., Dipl. A.C.V.B.  Published by MERCK & CO., INC.  Whitehouse Station, N.J., USA:  2005.

http://www.merckvetmanual.com/mvm/index.jsp

The Orthopedic Foundation for Animals (OFA):  Hip Dysplasia, Elbow Dysplasia, Patellar Luxation, Legg-Calve-Perthes, Cardiac, Thyroid, DNA, Congenital Deafness, Sebaceous Adenitis, Shoulder OCD information and Certification programs.  2005. http://www.offa.org/thyinfo.html  Email: ofa@offa.org
 

OFA: DNA Tests, Breeds, and Labs.  2005.  http://www.offa.org/dnatest.html

University of Pennsylvania:  School of Veterinary Medicine- Department of Clinical Studies, Philadelphia.  2005.

http://w3.vet.upenn.edu/research/centers/penngen/services/metaboliclab/methylmalonic.html

University of Pennsylvania Hip Improvement Program (PennHIP).  2005.  http://www.pennhip.org/

PennHIP Administrative Center at 215-573-3176 or by email pennhipinfo@pennhip.org