HEALTH
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Eyes:  Cataract: Like a camera, eyes have a clear lens inside them that is used for focusing. A cataract is any opacity within a lens. The opacity can be very small (incipient cataract) and not interfere with vision. It can involve more of the lens (immature cataract) and cause blurred vision. Eventually, the entire lens can become cloudy, and all functional vision lost. This is called a mature cataract. PRA 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. Animal Eye Care believes that in many of these PRA patients, specific oral antioxidant nutritional therapy can delay the progression of blindness. Blindness is not avoided, however, in any PRA patients. If oral antioxidants were used, they would be continued until complete vision loss occurred. PPM Persistent pupillary membranes, or PPMs as they are often called are common findings on CERF examinations. They may or may not be a problem in a breed and/or individual dogs. PPMs are remnants of a fetal structure called the pupillary membrane. This membrane covers the pupil before an animal is born. It is part of the blood supply to the developing lens (the structure in the eye that focuses light on the retina). Normally the pupillary membrane completely absorbs before birth in foals and calves but is partially present and continues to disappear in neonatal dogs. Absorption may not be complete in puppies when the eyes first open and small strands or a web-like structure may be seen across the pupil. These strands normally disappear by four to five weeks of age. In some dogs these strands do not disappear and become PPMs. PPMs may be found in several configurations in the anterior chamber (see figure). They may span across the pupil (iris to iris), from the iris to the lens, from the iris to the cornea, or they may float free on one end, only connected to the iris. In general, iris to iris PPMs cause no problems. They may be single strands or a forked structure. These PPMs may break and become less prominent as the puppy gets older, but they usually do not disappear completely. Iris to lens PPMs are more problematical. These PPMs cause opacities (cataracts) at the point where they are attached to the lens capsule. The cataracts do not usually progress and cause only minor visual deficits. Iris to cornea PPMs cause opacities on the cornea due to their ability to damage the corneal endothelium (the inner lining of the cornea). These opacities may be small or may be severe due to the development of corneal edema (fluid in the cornea). Severely affected puppies (with numerous strands) may be blind (they may improve as they get older). The strands may regress but do not disappear. PPMs are found in many breeds of dog. In most of these breeds, iris to iris PPMs are classified by CERF as a "breeder option" problem. This means that most of the PPMs which have been reported in these breeds have been small and are probably sporadically occurring and not hereditary defects. Dogs with these small iris to iris PPMs who have been bred have not been reported to have puppies with vision problems. This does not mean that problems will never occur in these breeds. Owners with dogs diagnosed with PPMs should be aware of the situation and should probably either not breed affected dogs or should breed the affected dogs only to unaffected dogs. In some breeds, PPMs are known to be hereditary and puppies who have any type of PPM will not receive a certification number. The Basenji is the most well known but CERF will also not certify Chow Chows, Mastiffs, Pembroke Welsh Corgis, or Yorkshire Terriers with PPMs. Members of these breeds have been shown to produce offspring with blindness directly associated with their PPMs. In these breeds, the mechanism of inheritance is not known but breeding any of these dogs with PPMs is highly discouraged. BODY: Patellar Luxation: The patella or kneecap is a moveable bone located over the knee that connects the muscles of the thigh to the lower leg. Patellar Luxation is a dislocation of the kneecap. This is more often found in smaller breeds of dogs. More often than not a dog was born with this condition and it was passed down from the parents infecting both legs. A symptom your dog may be affected with Patellar Luxation is to see him occasionally holding a leg in the air while he is running then start using it again later. Sometimes the dog may cry out when this takes place for the kneecap or Patella has popped out of place, then returned. Depending on the severity, surgery is often recommended to make the dog more comfortable and to prevent crippling arthritis or deformities. There are various techniques for correcting patellar Luxation, but regardless of the technique the purpose of the surgery is to re-establish the proper alignment of the quadriceps tendon, the patella, and the patella tendon to prevent a sideways slipping of the kneecap. All dogs used in breeding programs should be tested and certified, with each dog being tested more than once at different ages as some luxation will not be evident until later in life. Your breeder should show you proof that his/her dogs are tested and have a certificate showing the parents are free of this defect. 
 1. Patella knee-cap 2. Femur 3. Patellar ligament 4. Patellar ligament attachment 5. Medial luxation 6. Lateral luxation Demodicosis Demodectic mange, also called "demodicosis," is caused by a microscopic mite of the Demodex genus. Three species of Demodex mites have been identified in dogs: Demodex canis, Demodex gatoi, and Demodex injai. The most common mite of demodectic mange is Demodex canis. All dogs raised normally by their mothers possess this mite as mites are transferred from mother to pup via cuddling during the first few days of life. Most dogs live in harmony with their mites, never suffering any consequences from being parasitized. If, however, conditions change to upset the natural equilibrium (such as some kind of suppression of the dog's immune system), the Demodex mites may "gain the upper hand." The mites proliferate and can cause serious skin disease. Localized demodicosis: Localized demodicosis occurs as isolated scaly bald patches, usually on the dog's face, creating a polka-dot appearance. Localized demodicosis is considered a common puppyhood ailment and approximately 90% of cases resolve with no treatment of any kind. This is quite a contrast to generalized demodicosis as described below so it is important to be able to distinguish localized from generalized disease. It seems like this would be a simple task since localized demodicosis classically involves several round facial bald spots and generalized demodicosis involves a bald scaly entire dog; still, reality does not always fit into neat categories in this way. Some guidelines used to distinguish localized demodicosis include: • Localized disease does not involve more than two body regions. (One spot or two on the face and one spot or two on a leg would still qualify as localized even though the spots are not close together.) • Localized disease involves no more than 4 spots total on the dog. Treatment is not necessary or recommended for localized demodicosis but there are treatment options for people who simply cannot feel right about doing nothing. Goodwinol ointment, an insecticide, may be used daily to control localized demodicosis. Antibacterial gels are also used against localized demodicosis and associated skin infections. It is important to note that rubbing a creme or ointment on a demodicosis lesion can cause reddening of the lesion making it appear to get worse. It is also possible for rubbing the medication on the area to break off the weaker hairs at the margin of the lesion causing the lesion to appear to get bigger. Neither of these situations truly represents exacerbation of the disease. Resolution of a localized demodicosis lesion should be at least partially apparent after one month though total resolution can take up to three months. Approximately 10% of localized demodicosis cases will progress to generalized demodicosis. Enlarged lymph nodes are a bad sign -- often foretelling generalized mange. Generalized demodicosis: Classically with generalized demodicosis, the entire dog is affected with patchy fur, skin infections, bald, scaly skin. Sometimes large patches of affected skin are present, sometimes multiple "polka dots" of lesions cover the dog, and sometimes the entire body is involved. The secondary bacterial infections make this a very itchy and often smelly skin disease. The approach to generalized demodicosis typically depends on the age at which the dog developed the disease. Adult onset Most demodicosis occurs in young dogs, under age one and a half. An older dog should not get demodicosis unless he or she has an underlying problem with the immune system. In such cases, demodicosis is considered a indication to seek a more serious hidden condition such as cancer, liver or kidney disease, or an immune-suppressive hormone imbalance. A more extensive medical work-up will be required. Juvenile onset Young dogs have inherently immature immune systems and are thus susceptible to the development of demodicosis without any sinister underlying diseases. As they grow up and their immune systems mature, they tend to naturally gain control of their mite infestation; in fact, 30-50% of dogs under age 1 year recover spontaneously from generalized demodicosis without any form of treatment. Usually treatment is recommended, though, to facilitate recovery. |