Hereditary Diseases
Neurological Defects
Ceroid Lipofuscinosis
Ceroid Lipofuscinosis (CL) is a Border Collie inherited disease that ultimately results in the necessary euthanasia of the affected dog. The disease goes by a couple of other names and is related to a human disorder as well. It is sometimes called Border Collie Rage or Storage Disease. In humans the disease is similar to Battens Disease.
The disease seems to be autosomally recessive -- an affected gene from each parent needs to be inherited by the pup for CL to come into effect. Unfortunately, CL doesn't show up until the pup is nearing maturity at around two years of age.
CL prompts an enzymatic abnormality, which results in the buildup of waste materials in the brain. Behavioral aberrance, visual distortions, and violent disorientation occur cyclically, presenting a serious physical threat to both humans and kennelmates.
Other breeds of dogs, in particular the English Springer Spaniel, have had reports of similar behaviors associated with them. In some cases, one reported in an Australian Shepherd, the incidents appear related to a seizure disorder and maybe controllable with proper diagnosis and medication. Unfortunately, that's not the case with CL.
Epilepsy
Epilepsy occures in many breeds of dogs to some extent. In a few breeds it's a huge problem. Fortunately that's not the case in Border Collies. For more information on canine epilepsy, look on the Black Rock Links page.
Eye Defects
Acquired Retinal Atrophy
Centralized Progressive Retinal Atrophy
Collie Eye Anomaly
Collie eye (CEA) is inherited from both parents and results in varying degrees of blindness over time. A DNA test to determine a dog's genetic makeup with regard to the CEA gene was developed by Dr. Alan Wilton in Australia. All Black Rock dogs are now screened for CEA as puppies. Dogs who are CEA carriers can be selectively bred to normal dogs without fear of producing puppies that will eventually go blind. Two carriers, however, can not be bred together since that combination holds a significant probability that at least one puppy in the resulting litter will be CEA affected.
The CEA test is $250 per dog.
Hematological Defects
Trapped Neutrophil Syndrome
Trapped Neutrophil Syndrom (TNS) is inherited from both parents and usually results in a puppy who dies within three months of birth. A DNA test to determine a dog's genetic makeup with regard to the TNS gene was developed by Dr. Alan Wilton in Australia. All Black Rock Border Collies are now screened for TNS as puppies. Dogs who are TNS carriers can be selectively bred to normal dogs without fear of producing puppies that will die. But, given the severe nature of the disease, elimination of carriers from the breeding population is in the best interests of the breed.
Hereditary Skeletal Defects:
Hip dysplasia (HD) is found in all dog breeds and is basically a poor development of the hip joints. This disease is not caused by a single pair of genes, but instead is "polygenic." This means many gene pairs determine the condition and development of the hip joints. This disease is difficult to understand and to determine the genetic inheritance involved is equally complex. Additionally, there are environmental factors that can produce HD in dogs with no genetic predisposition for the disease.
The incidence of HD is reduced by careful selection of breeding stock. Dogs with HD exhibit symptoms from lameness varying from slight to very severe crippling. The lameness is usually noted between six months to a year of age, or in the dog's older years (clinical dysplasia). Some dogs never show lameness at all but, nonetheless, have the disease (radiographic dysplasia). These dogs run, jump, and play vigorously, but still carry the disease and can pass it along in its clinical form to their offspring.
HD can only be diagnosed through x-rays analyzed by a competent veterinarian. The Orthopedic Foundation for Animals (OFA) has served for many years as the diagnostic expert for this disease. X-rays submitted to the OFA are sent to three independent veterinary radiologists for a consensus opinion. OFA will not certify a dog free from HD until the animal is two years old. Dogs may be x-rayed for a preliminary evaluation earlier than two years, but because of the progressive nature of the disease, certification is only granted when x-rays taken after the second birthday are submitted.
