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Last update - 8/15/00 Content Provider: Jim Orsborn Copyright © 2000 STCA |
 Genetic Health Issues
Introduction Much of the material presented in this section were written by Cindy Cooke.
Scottie Cramp Scottie Cramp is the most wide-spread hereditary disorder in the breed and it is also the least serious, from the dog's point of view. Affected dogs are normal at rest and exhibit normal ability to walk until they are stressed. Common stimuli are exercise, hunting, fighting, or courtship. As the dog's level of stress increases, his gait begins to change. The forelegs move out to the side and forward rather than straight forward, called winging. The spine in the lumbar area may arch and the rear legs begin to overflex. If the excitement or exercise continues, the dog begins to exhibit a "goose-stepping" gait. If the dog is running, he may somersault and fall. Severely affected dogs may find their ability to walk or run completely inhibited. This is not a seizure. There is no loss of consciousness. As soon as the stimulus abates, the symptoms disappear almost immediately. The severity of symptoms in affected dogs varies widely as does the amount and type of stimulation necessary to elicit clinical signs. The symptoms appear to be caused by a buildup or depletion of some chemical compound in the dog's central nervous system, most probably serotonin. In layman's language, the signal from the brain telling the dog how to run gets garbled in transmission on its way to the various muscles. The Scottie's muscles are not cramping and he is not experiencing pain. He has just temporarily lost the ability to coordinate his movements. Scottie Cramp is present from birth, but it often takes the eye of an experienced breeder to spot it. Affected dogs soon learn to anticipate the onset of cramping and abruptly stop running or playing. By the time such a puppy is grown, he may never exhibit any signs at all. Similarly, an affected dog with a very laid-back personality is less likely to exhibit symptoms than a more hyperactive Scot. Scottie Cramp is a permanent condition, but it does not worsen with age. Nearly all dogs affected with Scottie Cramp make perfectly wonderful companions, able to share virtually all activities with their families. Treatment is seldom necessary but, in severe cases, Vitamin E, diazepam and Prozac have all proven to be effective. Von Willebrand's Disease Von Willebrand's Disease (VWD) is the name given to a group of similar inherited bleeding disorders that occur in humans, pigs, dogs and rabbits. VWD is usually less clinically severe than hemophilia and is inherited as an autosomal trait. This means that it can be transmitted equally by and to both sexes. Carriers are asymptomatic but affected dogs may exhibit any of the following symptoms: * Excessive bleeding when the nails are cut too short * Severe bleeding during surgery * Bleeding from the nose or gums, particularly during teething * Bleeding from the vagina or penis * Hematomas on the surface of the body, limbs or head * Internal bleeding * Lameness from bleeding into the joints * Stillbirths or neonatal deaths with evidence of hemorrhage at autopsy * Chronically infected and bloody ears * Prolonged bleeding during the heat cycle or after whelping * Bleeding in stools or urine A simple DNA test to detect
Von Willebrand's Disease is now available from Vetgen.
Cushing's Syndrome Cushing's Syndrome is a collection of symptoms caused by an excess of a hormone called cortisol. There are three main causes of Cushing's Syndrome: a tumor on the pituitary gland; a tumor on the adrenal gland; or veterinarians who over-prescribe corticosteroids to treat itching skin. It is, as yet, unknown whether there is an inherited predisposition to Cushing's Syndrome in Scottish Terriers. Your Scottie should be checked for Cushing's if: * He is drinking huge amounts of water and urinating frequently * He is losing coat * His skin is darkening * His muscles are atrophying and he develops a pot belly. If your vet finds the following four symptoms, your Scottie probably has Cushing's Syndrome: * The dog is drinking copious amounts of water and urinating frequently. * The dog has an elevated SGPT. * The dog has an elevated alkaline phophatase level. * The dog's ratio of urinary cortisol to urinary creatinine is greater than 24 Cushing's Syndrome is usually treated successfully with a drug called Lysodren. Surgery is rarely recommended and radiation therapy, used in humans, is very expensive and rarely available for dogs. Hypothyroidism Hypothyroidism is an underproduction of hormones by the thyroid gland. Symptoms of hypothyroidism include: * Abnormal loss of coat (often bilateral and symmetrical), poor coat condition, fading of coat color * Chronic skin disorders and infections, skin allergies, dry or scaling skin * Weight gain * Infertility * Fatigue, lethargy * Intolerance of cold It is important to determine the exact cause of your dog's hypothyroidism before embarking on a course of treatment. Your veterinarian must run a full thyroid panel and have the blood tested at a laboratory which uses canine thyroid values. Do not be tempted to start thyroid treatment without proper veterinary supervision. The balance of the endocrine system is critical to your dog's health and you can cause an otherwise healthy thyroid gland to atrophy by giving medication improperly. Epilepsy Seizures may be caused by a number of conditions, including low blood sugar, brain tumor, heat stroke, poison, nutritional deficiency and distemper. Classic or idiopathic (meaning "of unknown cause") epilepsy is characterized by recurrent seizures with no active underlying disease process occurring in the brain. This form of epilepsy is not usually seen until a dog is mature, usually between three and five years of age. In a typical seizure, the dog will salivate excessively. There is usually dilation of the pupils and stiffening of the limbs. The dog may arch its back and paddle its legs. Frequently, the dog's temperature will spike up three to five degrees. Urination or defecation may accompany or follow the episode. Seizures usually last only a minute or two, but severely affected dogs may have longer and more frequent episodes. Dogs who have infrequent seizures do not require treatment. When treatmen is required, phenobarbitol, dilantin and primidone are frequently used. In recent years, there seems to be an increase of reported seizures in Scottish Terriers. While some of the increase may be due to environmental hazards, inherited epilepsy has definitely made inroads into the Scottie gene pool. Craniomandibular Osteopathy Craniomandibular Osteopathy (CMO) is an inherited disorder characterized by an abnormal growth of the bone of the lower jaw. CMO usually appears between four and seven months. A puppy with CMO usually pulls away, flinches or screams with pain when his mouth is examined, depending on the severity of the disease. Other early symptoms are lethargy, fever and unwillingness to eat. An acutely affected puppy may be unable to open his mouth but mild cases may be misdiagnosed as teething problems or virus symptoms. An accurate diagnosis of CMO requires X-ray confirmation. CMO is nearly always treatable. Mild cases respond to aspirin or other non-steroidal anti-inflammatory drugs such as ibuprofen or while acute cases may require the use of steroids such as prednisone or prednisolone. Fortunately, as the dog matures, the abnormal bony growth abates and is often undetectable in the adult dog, even by radiography. Back to Top Liver Shunts To date, liver shunts have been reported in fewer than a dozen dogs but there are several lines that have displayed the problem. Most of what we know about liver shunts comes from research done on Yorkshire Terriers, a breed where this problem is widespread. While we know that the problem is inherited, the mode of inheritance is unknown. Vets at the University of Missouri School of Veterinary Medicine have been working trying to answer this question with a colony of Yorkies with repaired liver shunts but have been unable to get any of the bitches pregnant. The Scottish Terrier Club of America is now looking into the possibility of developing a DNA test to detect the carrier status of this problem. Liver shunt can be difficult for a breeder to recognize but is easily diagnosed with a bile acid test. Affected puppies are normally small and unthrifty. After eating, they can exhibit bizarre behavior caused by a buildup of ammonia in the bloodstream. Surgery can normally correct the condition, depending on the location of the shunt, but it's not always completely effective and it's very expensive, often running into thousands of dollars. Geneticists recommend that dogs who produce liver shunt should not be bred again and that the siblings of an affected dog should also be spayed/neutered. Back to Top Juvenile Cataracts To date, only a few dogs have been affected by juvenile cataracts and apparently only one line. In Miniature Schnauzers, congenital juvenile cataracts are caused by a simple autosomal recessive gene. In other words, both parents must be carriers. For years, many responsible Schnauzer breeders kept blind dogs and bitches to use for test-breeding their stock. Hopefully, the breeders of these affected dogs will do the right thing by removing the sires and dams who have produced this problem from the gene pool. A deep cut now could prevent generations of suffering later. Back to Top
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