Hunde-Gesundheit

Cataract = Eye disease (eye cataract))

Cataracts

Cataracts are one of the most common eye problems affecting pets. They can affect all breeds and ages of dogs and cats, but the condition is found more commonly in certain dog breeds, such as Cockers, Poodles, Miniature Schnauzers and Terriers.

The normal, transparent lens in the eye focuses beams of light onto the retina so that your pet can see clearly. A cataract is a disruption of the normal arrangement of the lens fibers that interferes with sight by partially or completely blocking the clarity of the lens. A cataract may be quite small and not significantly interfere with your pet's vision, but if the cataract becomes dense enough, vision may be lost.

It is not unusual for your pet's eyes to become slightly blue-gray as they age. As a normal part of the aging process, the lens becomes thicker, making the eyes appear grayer. This condition, called nuclear sclerosis, usually occurs in dogs over six years of age and typically does not affect their vision. Therefore treatment for this condition is not recommended.

Cataracts can be hereditary or due to old age. Inherited conditions are the most common cause of cataracts and may be present at birth or develop when the animal is very young. They can also be caused by injury, or illness such as diabetes. If your pet's cataracts are due to an underlying condition, such as diabetes, treating the condition may diminish the cataracts.

There is no effective medical treatment for cataracts. Cataracts are not painful, but when your pet has trouble navigating due to vision loss, his sight can be restored to near normal through surgery. A veterinary ophthalmologist will surgically remove the lens, replacing it with a plastic or acrylic prosthetic lens to allow for more focused vision. Cataract surgery generally has a 90-95% success rate, but it is also a very delicate procedure that requires extensive postoperative care by the pet owner.

After surgery, your pet will have to wear a protective collar (Elizabethan Collar) until his eye heals and you will need to keep him quiet and calm. Your pet will also require eye drops to be administered several times a day for a few weeks.

You and your veterinarian can decide if cataracts are affecting your pet's vision enough to warrant surgery. For more information, consult with your veterinarian.

PRA = Progressive Retinal Atrophie in Dogs )

This is a genetic, inherited disease of the retina (the "film" in the camera), which occurs in both eyes simultaneously. The disease is nonpainful, and there is no cure for it. The eyes are genetically programmed to go blind. PRA occurs in most breeds of dogs and can occur in mixed breeds also. It is recessively inherited in all breeds studied, with the following exceptions: PRA is dominantly inherited in Old English Mastiffs and Bullmastiffs, and PRA is sex-linked and found primarily in male dogs in the Siberian Husky and Samoyed breeds.

Clinical signs vary from the dog first becoming night blind in the early stage of PRA (not able to see in low light surroundings) to the entire visual field in all light levels becoming affected, which is advanced PRA. The pupils are usually dilated, and owners often notice a "glow" and increased "eye shine" from the eyes. All dogs with PRA will eventually develop blindness from advanced PRA, and this time frame until the dog is blind varies considerably from dog to dog, but usually takes at least 6 months from the time of diagnosis, and can rarely take years until the dog is completely blind. Although no treatment for PRA is possible to stop the disease, nutritional antioxidant supplementation for retinal health may help slow the deterioration of the retina to "buy some time" before the blindness inevitably happens. Many veterinary ophthalmologists do not recommend oral nutritional therapy for dogs with PRA, because there has been no research on the effect of oral antioxidants on dogs with PRA. However, Animal Eye Care believes that in some of these PRA patients, specific oral antioxidant therapy can delay the progression of blindness. Blindness is not avoided, however, in any PRA patients. If an oral antioxidant were used, it would be continued until complete vision loss occurred.

What to do if you suspect PRA:
Have your dog examined by a board certified veterinary ophthalmologist to determine if this disease is indeed present. If you are located in the Pacific Northwest, you may contact our office to schedule a comprehensive ophthalmic examination. Dogs with PRA should not be bred, and the breeder that you received your dog from should be notified that the dog is affected, so the breeder can alter their breeding program in future. It is important to understand that dogs with PRA are happy dogs. Their eyes don't hurt, and they adjust very well to their slow loss of vision. In fact, if a dog were destined to become blind and Dr. McCalla could pick the disease, it would be PRA, as the vision loss is slow and nonpainful, and the dog is given much time to adjust to its vision loss.

It is important to realize that it is OK to grieve about your pet's vision loss, but you must not put your sad feelings in your dog's head--they aren't really there! Your dog is not suffering. They adjust well to their vision loss, and it is by far hardest to deal with on the owner's side. Your dog's job description has not changed. Your blind dog is happy as long as its routine is stable. From your dog's point of view, life continues to be great-- you are there as always, and they just need to use their other keen senses a bit more to get the same information they used to view. Keep household furniture in its place, and consider purchasing the book "Living With Blind Dogs" by Caroline Levin. Animal Eye Care also sells this book. It is the only book of this subject matter, and is beneficial in helping owners and their affected pets adjust to the vision loss.

Dogs with PRA can develop cataracts late in the disease process. Cataract surgery would never be done, as it would not help the dog to see. However, cataracts can cause pain and damage to the eye, and if the eyes look very cloudy to you, please call Animal Eye Care for a reexamination as soon as possible.

There are DNA blood tests available, to determine if dogs are likely affected with PRA, are likely carriers for PRA, or are not likely carrying the PRA gene. This test is available for the following breeds: Briard, Cardigan Welsh Corgi, Chesapeake Bay Retriever, Nova Scotia Duck Tolling Retriever, English Cocker Spaniel, Irish Setter, Labrador Retriever, Portuguese Water Dog, Toy and Miniature Poodles, Sloughi, Old English Mastiff and Bullmastiff, Miniature Schnauzer, Siberian Husky, and Samoyed. Please visit the web site for further information (www.Optigen.com). Additionally, studies for Late Onset PRA in Tibetan terriers and PRA in Jack Russell Terriers are being conducted at the University of Missouri-Columbia. For blood sample collection kits and more information about these research studies, please contact: Liz Hansen, coordinator of Veterinary Information, Dr. Gary Johnson's Laboratory at hansenl@missouri.edu [phone number: (573) 884-3712]. Please also view the article about the disease in Tibetan Terriers at the CERF web site (www.vmdb.org)

CLAD = Canine Leukocyte Adhesion Deficiency from website of: www.optigen.com

For: Irish Setters and Irish Red & White Setters

Technically known as Canine Leukocyte Adhesion Deficiency, this rare but devastating condition is an inherited fatal immunodeficiency disease. Pups that inherit two recessive genes for CLAD usually die early in life from multiple severe infections, even when treated with massive doses of antibiotics.

CLAD is related to the same disease in humans (LAD) and cattle (BLAD). So far, CLAD has been found only in Irish Setters. Research on the disease was carried out in England and Scandinavia, where the carrier rate is close to 12%. However, CLAD was first identified clinically in the United States.

Reliable identification of dogs that do not carry disease genes is the key to eliminating autosomal recessive diseases such as CLAD. Now OptiGen offers a new DNA-based test that provides a method to eliminate Canine Leukocyte Adhesion Deficiency, or CLAD from the Irish Setter.

As a mutation-based gene test, the CLAD test unequivocally and specifically identifies normal dogs. Called "genetically clear," "noncarriers" or, more formally, "homozygous normals," such dogs can pass only the gene for normal leukocyte (white blood cell) function on to all their pups.

The test also identifies carriers (heterozygous dogs) with 100% accuracy. These carriers can be safely bred to "clears." Their recessive genes can only cause disease when matched with the recessive gene of another carrier. Performed early enough, this test will accurately identify affecteds as well. But affecteds usually don't survive to breeding age.

It isn't necessary to remove those carriers which are otherwise excellent dogs from the breeding population. But given the lethal nature of the disease, it is best to select against carriers who are not superlative dogs, so as to entirely eliminate the gene from a line within two or three generations.

Latest Information

Irish Red & White Setters – Testing for PRA and CLAD

The DNA-based genetic tests for the rcd1 form of Progressive Retinal Atrophy (PRA) and for Canine Leukocyte Adhesion Deficiency (CLAD) are identical for both Irish Setters and Irish Red & White Setters. The information given above on this page for Irish Setters therefore can be applied to Irish Red & Whites as well.

As more Irish Red & Whites are screened for the rcd1-PRA mutation with the DNA test, we will generate an estimate of the mutation frequency.

CLAD has been reported in Irish Red & Whites in Europe and recent screening done there for the CLAD mutation confirms that the mutation is in these lines. Out of 76 Irish Red & Whites screened, six were carriers with the CLAD mutation. (reported by Debenham, Millington, Kijas, Andersson and Binns, Journal of Small Animal Practice. Vol 43, February 2002.) Again, as more dogs are tested, an estimate of mutation frequency will be generated specifically for the US.

Canine Hip Dysplasia (HD))

Hip dysplasia is a genetic disorder in which dogs have a poor fitting hip joint. This ball and socket joint should fit together neatly, allowing dogs to move the legs freely and without pain. Because their bones do not fit properly, dogs with hip dysplasia are prone to develop arthritis and related joint pain as they age. Motion of the hip joints slowly causes erosion of soft cartilage in these joints. Hip dysplasia can affect either or both of the rear leg joints.

Hip dysplasia can occur in most breeds, but it is predominant in larger dogs, particularly the German Shepherd, St. Bernard, Labrador Retriever, Pointers, and Setters. Although hip dysplasia is a genetic condition, research shows that environmental factors can also put a dog at risk. Overfeeding (especially of puppies) can predispose a dog to hip dysplasia. Excessive exercise may predispose dogs as well.

Diagnosis: Signs of severe hip dysplasia usually appear before the dog reaches one year of age. Signs include rear leg pain, incoordination, and a limp or wavering gait. A common sign is the dog that has trouble rising. Dogs with severe hip dysplasia typically develop lameness by two years of age. Dogs with less severe cases may not experience arthritis and the related pain or lameness until six to ten years of age.

Since the clinical signs of hip dysplasia are similar to those of other diseases, veterinarians rely on X-rays to make a final diagnosis. This requires a mild anesthetic in order to carefully position the dog on the radiographic table. Veterinarians look for degenerative changes and abnormal shapes of the hip joint.

Treatment: Depending on the severity of the dog's condition, veterinarians treat hip dysplasia with either drugs or surgery. Drug therapy doesn't reverse or cure the progression of hip dysplasia, but it does offer relief from the associated pain. There are several steroidal and non-steroidal, anti-inflammatory drugs available through veterinarians. Most require daily administration. For many dogs, these prescriptions can offer a tremendous relief--they return to a more active lifestyle that is free of joint pain.

Recent advances in veterinary medicine have made surgery a more successful option for treating severe cases of hip dysplasia. Surgeons can improve the joints in young dogs by making changes to the shape of the femur or pelvis. Another surgery option is hip replacement, which replaces the joint with a stainless steel ball and socket.

Dogs with hip dysplasia should not live a sedentary lifestyle that is free of exercise. By carefully allowing your dog to exercise, at her own pace, you can help loosen up the stiffness in joints. Pet owners should also pay close attention to their dog's weight. Just a few extra pounds can cause skeletal stress and increase your dog's pain. Another precautionary measure is to keep your dog out of the cold. Don't allow your dog to sleep in a drafty area, as the cold can aggravate her arthritis.

Breeding: To prevent passing on hip dysplasia to puppies, pet owners should use extreme caution before breeding their dogs. Large breed dogs that are prone to hip dysplasia should be radiographed by a veterinarian to rule out the condition prior to breeding. Since the signs of hip dysplasia may not be evident until a dog is fully grown, these radiographs should not be performed until the dog is at least two years of age.

For more information regarding canine hip dysplasia, consult with your veterinarian. As with all pet health care issues, your veterinarian is the best source for information concerning your individual pet's health care needs.