Overview
A number of tests are available for the Old English Sheepdog. Two or more of these tests purchased as part of this bundle will be discounted.
- Collie Eye Anomaly associated with the NHEJ1 gene
- Degenerative Myelopathy associated with the SOD1 gene
- Exercise Induced Collapse associated with the DNM1 gene
- Multi-Drug Resistance with the ABCB1 gene
- Multiocular Defect associated with the COL11A1 gene
Collie Eye Anomaly
*Optigen Officially Licensed*
Collie Eye Anomaly/Choroidal Hypoplasia (CEA/CH) is a developmental defect of the eye. Specifically, the abnormal development of the choroid – an important layer of tissue under the retina of the eye – in which there is a decrease in the development of the blood vessels. Puppies can be diagnosed by an ophthalmologist as early as 6-8 weeks of age. As the puppies get older the tapetum (the reflective layer at the back of the eye) develops and this can hide the signs of CEA. This phenomenon is called “go normal”, but it does not mean that CEA goes away or gets better. Affected dogs can also have optic disc coloboma and retinal detachment.
Degenerative Myelopathy
Important: Degenerative Myelopathy is a rare disease that presents most commonly in German Shepherd Dogs and Boxers, sporadically in Pembroke Welsh Corgis, Cardigan Welsh Corgis, Bernese Mountain Dogs, Rhodesian Ridgebacks, Borzoi and Chesapeake Bay Retrievers. It is rarely diagnosed in other breeds or mixed-breed dogs. DM is considered genetically complex and will have more than one contributing genetic variant. The variant targeted by this test is widespread and found in more than 120 breeds. However, association of the variant with the disease has only been shown in very few breeds and should never be used to inform breeding decisions, except where close relatives have been clinically diagnosed.
Canine degenerative myelopathy (previously also known as chronic degenerative radiculomyelopathy) is a progressive disease of the spinal cord in older dogs. Most dogs are at least 8 years old before clinical become apparent. DM usually starts with a muscle weakness, loss of muscle and loss of coordination (ataxia) in the hind limbs. Progression is generally quote slow, but dogs will eventually be crippled within approximately 3 years of the onset of disease.
Exercise Induced Collapse
Exercise Induced Collapse (EIC) is an inherited condition that primarily affects Labrador Retrievers and their related breeds – mainly Labrador crosses. The variant responsible has also been found in other breeds, including Curly-coated Retrievers, Boykin spaniels and Pembroke Welsh Corgis. The signs of EIC typically become noticeable when dogs undergo rigorous training. The initial symptoms usually manifest between the ages of 5 months and 3 years, although there have been cases where affected dogs didn’t experience collapse episodes until as late as age 10. Dogs with this condition can tolerate mild to moderate exercise, but after engaging in heavy exercise for a duration of 5 to 20 minutes, they experience weakness and collapse. While some dogs may only exhibit collapse episodes sporadically, severely affected dogs can collapse whenever they are exercised to this extent. The condition can be exacerbated by excitement and high temperatures.
Multi-Drug Resistance
In certain breeds a mutation on the ABCB1 gene, which encodes the MDR1 protein (which stands for Multi Drug Resistance 1) can cause animals that carry the mutation to be particularly sensitive to certain drugs. The variant was first detected in a subpopulation of dogs that were highly sensitive to Ivermectin-induced neurotoxicity. The variant on the ABCB1 gene results in the brain being unable to efficiently pump some drugs out, causing a toxic build-up of these drugs in the brain. Dogs subsequently experience and range of symptoms from vomiting and diarrhea to lethargy, seizures, or coma.
Multiocular Defect
Multiocular defect is an inherited syndrome with affected dogs presenting with multiple and various ocular abnormalities. A mutation in COL11A1 causes MOD in the Old English Sheepdog breed. Clinical signs in affected dogs include cataract, microphakia, macrophthalmos, lens coloboma, retinal folds and detachment, vitreous anomalies/degeneration and persistent pupillary membranes, although not all affected dogs display all of these abnormalities Heterozygous dogs might have fewer clinical signs than homozygous dogs and/or a later onset of disease.
