PLL - Primary Lens Luxation
The lens is located behind the iris and a part is visible through the opening of the pupil. The lens is kept in place by small fibers called zonules. When these zonules break the lens becomes detached. The lens can now slide through the opening of the lens into the anterior chamber. Or it moves backwards into the vitreous body. If the zonules partly break we speak of lens subluxation, total detachement is called lens luxation.
When the lens comes in contact with the cornea it can do much damage. Also the lens can block the flow of the aqueous fluid in the eye. The pressure in the eye will increase. As a result of this a Glaucoma will occur.
Lens luxation can be inherited but also trauma, inflammation and Glaucoma can be the cause of it.
Treatment of lens luxation depends on where the lens is located (this can be either in the anterior chamber or in the vitreous body), the presence of Glaucoma and the visibility of the affected eye. With an early diagnosis vision in the affected eye could be saved by removing the lens out of the anterior chamber. But in most cases the eye can't be saved and maybe then it's better to remove the affected eye for this is a very painful condition.
When the lens is located in the vitreous body in most cases the option would be to give eyedrops (lifelong) that will keep the pupil small making it impossible for the lens to move into the anterior chamber. This type of luxation, with the lens located in the virtreous body, should not be painful for the dog and it should even be possible to see with the affected eye.
With heredity lens luxation both eyes will be affected. In some cases the lenses of both eyes will get loose at the same time but in most cases there will be a time between the loosening of the first lens and the second one. This can take weeks, months or even years.
The signals of lens luxation can vary between minor to extreme pain to the eye, red coloring of the white of the eyeball, cloudyness of the cornea, tearing and blindness.
When the lens comes in contact with the cornea it can do much damage. Also the lens can block the flow of the aqueous fluid in the eye. The pressure in the eye will increase. As a result of this a Glaucoma will occur.
Lens luxation can be inherited but also trauma, inflammation and Glaucoma can be the cause of it.
Treatment of lens luxation depends on where the lens is located (this can be either in the anterior chamber or in the vitreous body), the presence of Glaucoma and the visibility of the affected eye. With an early diagnosis vision in the affected eye could be saved by removing the lens out of the anterior chamber. But in most cases the eye can't be saved and maybe then it's better to remove the affected eye for this is a very painful condition.
When the lens is located in the vitreous body in most cases the option would be to give eyedrops (lifelong) that will keep the pupil small making it impossible for the lens to move into the anterior chamber. This type of luxation, with the lens located in the virtreous body, should not be painful for the dog and it should even be possible to see with the affected eye.
With heredity lens luxation both eyes will be affected. In some cases the lenses of both eyes will get loose at the same time but in most cases there will be a time between the loosening of the first lens and the second one. This can take weeks, months or even years.
The signals of lens luxation can vary between minor to extreme pain to the eye, red coloring of the white of the eyeball, cloudyness of the cornea, tearing and blindness.
PRA - Progressive Retinal Atrophy - prcd
PRA – Progressive Retinal Atrophy – is a broad category of disease that includes several types of retinal degenerative disease. One of these is prcd – progressive rod-cone degeneration. Prcd-PRA is the predominant type - by far - in many breeds currently being OptiGen tested. The OptiGen prcd-PRA mutation test detects only the prcd form of PRA and none other.
A diagnosis of vision loss could be due to various causes. Maybe some type of known inherited PRA. Or maybe another type of PRA not yet testable. Or maybe a condition that isn’t a primary retinal problem at all, for example a secondary degeneration of the retina caused by a non-genetic disease. Even vision loss due to cataracts or detached retina is sometimes confused with PRA. Accurate diagnosis by a qualified specialist is extremely important.
The test lets you identify normal dogs clear of the disease gene so you can better plan breeding strategies. It tells the status of an individual dog and gives a more accurate assessment of the risk of developing PRA, and eliminates the need for future ERGs in those dogs whose tests come back Normal/Clear or Carrier.
More info about the prcd-PRA gene test: www.optigen.com
A diagnosis of vision loss could be due to various causes. Maybe some type of known inherited PRA. Or maybe another type of PRA not yet testable. Or maybe a condition that isn’t a primary retinal problem at all, for example a secondary degeneration of the retina caused by a non-genetic disease. Even vision loss due to cataracts or detached retina is sometimes confused with PRA. Accurate diagnosis by a qualified specialist is extremely important.
The test lets you identify normal dogs clear of the disease gene so you can better plan breeding strategies. It tells the status of an individual dog and gives a more accurate assessment of the risk of developing PRA, and eliminates the need for future ERGs in those dogs whose tests come back Normal/Clear or Carrier.
More info about the prcd-PRA gene test: www.optigen.com
KCS - Dry Eye
Dry Eye (Keratoconjunctivitis sicca) is caused by abnormal tear production. The eye glands produce a watery secretion that make up the bulk of the tears. Dry Eye is caused by a deficiency in this secretion.
Normal tears are essential for the health and transparency of the cornea (the surface of the eye). Tears cleanse and lubricate the cornea, carry nutrients, and play a role in the control of infection and in healing. Deficient tear production as in Dry Eye causes chronic irritation of the cornea and conjunctiva. Corneal ulcers and eventually corneal scarring occur, and blindness can result.
Dry Eye can also occur as a result of viral infection, inflammation, drug-related toxicity, or immune-mediated disease. There is an association between removal of a prolapsed nictitans gland ("cherry eye") and the development of Drey Eye.
Normal tears are essential for the health and transparency of the cornea (the surface of the eye). Tears cleanse and lubricate the cornea, carry nutrients, and play a role in the control of infection and in healing. Deficient tear production as in Dry Eye causes chronic irritation of the cornea and conjunctiva. Corneal ulcers and eventually corneal scarring occur, and blindness can result.
Dry Eye can also occur as a result of viral infection, inflammation, drug-related toxicity, or immune-mediated disease. There is an association between removal of a prolapsed nictitans gland ("cherry eye") and the development of Drey Eye.
Patellar Luxation
Along with nearly all toy breeds, the Chinese Crested is genetically predisposed to patellar luxation, or slipping of the knee caps. This is caused when the indentation the patella (knee-cap) sits in is too shallow to properly form the knee joint. There are varying degrees of severity with the moderate to sever luxations requiring surgery to repair the knee and to prevent lameness and pain in the animal. Patellar Luxation can be tested for by manual manipulation of the knee by your veterinarian. The OFA (Orthopedic Foundation for Animals) certifies the absence of Patellar luxation and breeders should be able to provide proof of testing with either and OFA certificate or OFA form signed by their veterinarian.
Though testing of parent animals greatly reduces the incidence of patellar luxation in offspring, it is not a guarantee that a pair of animals who have been tested clear of patellar luxation will not produce an affected puppy. Always make sure that you have a written health guarantee from your breeder covering patellar luxation for at least one year, the age at which a dog may be certified clear of patellar luxation. Most responsible breeders provide health guarantees that are long term (4 or more years of coverage)
Patellar Luxation is graded from 1 to 4, in which 4 is the most severe case. Grade 1 can become a grade 4.
Grade
Though testing of parent animals greatly reduces the incidence of patellar luxation in offspring, it is not a guarantee that a pair of animals who have been tested clear of patellar luxation will not produce an affected puppy. Always make sure that you have a written health guarantee from your breeder covering patellar luxation for at least one year, the age at which a dog may be certified clear of patellar luxation. Most responsible breeders provide health guarantees that are long term (4 or more years of coverage)
Patellar Luxation is graded from 1 to 4, in which 4 is the most severe case. Grade 1 can become a grade 4.
Grade
- The Patella can be luxated manually and returns to the trochlea when released. Tibial rotation is minimal. Occasional luxation occurs but in general the dog won't feel inconvenienced.
- The Patella can be easily luxated manually and remains luxated until replaced. Luxation occurs frequently, causing the leg to be carried or used without full extension. Tibial rotation is present.
- The patella is permanently luxated, but can be replaced manually. The dog often uses the leg, but without full extension. Tibial rotation is marked.
- The patella is permanently luxated and can't be replaced manually. Extension of the leg is impossible. Tibial rotation is quite severe, resulting in a "bow legged" appearance. Surgical correction generaly needed.
Entropion
Entropion is the rolling inwards of the eyelid. It causes ocular pain and corneal disease. If the eyelid is rolled inward sufficiently so that the hairs of the eyelid rub on the eye, much damage may be done. Dogs with entropion usually squint and have watery eyes. If the entropion is not corrected and the rubbing continues, ulcers often develop on the cornea and the cornea becomes pigmented. Vision may be lost. Dogs that have had entropion correction surgery cannot be shown.
Cataract
The lens is a clear, transparent body in the eye. The lens doesn't contain bloodvessels so for its metabolism depends on the surrounding fluids which mainly consisting of water and proteine.
In a healthy eye incoming light falls through the lens onto the retina. Light is then transfered in nerve signals and sent to the brain which create the images. To get clear images the lens should be completely clear. In case of a cataract the proteine in the lens clot together. The lens will become clouded and the amount of light reflected on the retina will decrease. These cloudiness will lead to loss of eyesight, the images will be blurred.
When the cataract is small the cloudiness will only affect part of the lens and there only appears little signs of sightloss. Cataracts do grow and in time the conditions will get worse and finally every incomming vision will be projected blurred. At the point that the whole lens is infected, there will be no vision left with the infected eye.
Cataracts can be inherited but also occur due to aging, trauma, nutrition deficiency, diabetes and poisening. A cataract can also lead to lens luxation and Glaucoma.
Cataracts can be surgically removed but wether such an operation is meaningful depends on the amount of growth and sightloss.
In a healthy eye incoming light falls through the lens onto the retina. Light is then transfered in nerve signals and sent to the brain which create the images. To get clear images the lens should be completely clear. In case of a cataract the proteine in the lens clot together. The lens will become clouded and the amount of light reflected on the retina will decrease. These cloudiness will lead to loss of eyesight, the images will be blurred.
When the cataract is small the cloudiness will only affect part of the lens and there only appears little signs of sightloss. Cataracts do grow and in time the conditions will get worse and finally every incomming vision will be projected blurred. At the point that the whole lens is infected, there will be no vision left with the infected eye.
Cataracts can be inherited but also occur due to aging, trauma, nutrition deficiency, diabetes and poisening. A cataract can also lead to lens luxation and Glaucoma.
Cataracts can be surgically removed but wether such an operation is meaningful depends on the amount of growth and sightloss.
Glaucoma
The eyeball is filled with a vitreous fluid that in a healthy situation is supplied and discharged continuously. The amount of vitreous fluid determines the inner pressure and the shape of the eyeball. Glaucoma is an increase in this pressure. In most cases the drainage canal is being blocked whilst the input of fresh fluid continues. This will cause the eye to deform and is an extremely painful condition.
Due to the increased pressure in the eyeball the optic nerve at the back of the eye will be pressured. The optic nerve sends signals to the brain to form images. When to much pressure is exerted onto the optic nerve it loses its ability to function properly and the eyesight fails.
Glaucoma can be caused by heredity, trauma, inflammation, eyetumor and lens luxation. If the Glaucoma is the result of heredity, both eyes could become affected. Glaucoma is generally diagnosed in one eye initially. It may not appear in the second eye for 5 months, up to 2 years.
Glaucoma can cause acute blindness within 24 hours. However, it can also take weeks/months before blindness occurs. It depends totally on how rapid the increased pressure in the eye damages the optic nerve. This is why it's so important that you consult your vet immediately when any signs of eye problems/injuries occur. If the pressure can be decreased within 24 hours of onset, there is a chance the vision may be saved in the affected eye. However, even if the pressure has been present for a considerable time and vision has been lost, the pain caused by the increased pressure is still severe.
Glaucoma in early stages can be recognised by a mild eye infection, excessive tearing, pain to the eye, squinting of the eye, sensitivity to light and cloudiness of the cornea. Glaucoma in a later stage can be recognized by the reddish color of the white (sclera) of the eye, an increase in the size of the eye or eyelids that do not close completely. In almost all cases, this is the stage glaucoma is diagnosed. Medication/surgery will be necessary to relieve the dog of this extreme pain. The vision can't be restored in the affected eye.
Due to the increased pressure in the eyeball the optic nerve at the back of the eye will be pressured. The optic nerve sends signals to the brain to form images. When to much pressure is exerted onto the optic nerve it loses its ability to function properly and the eyesight fails.
Glaucoma can be caused by heredity, trauma, inflammation, eyetumor and lens luxation. If the Glaucoma is the result of heredity, both eyes could become affected. Glaucoma is generally diagnosed in one eye initially. It may not appear in the second eye for 5 months, up to 2 years.
Glaucoma can cause acute blindness within 24 hours. However, it can also take weeks/months before blindness occurs. It depends totally on how rapid the increased pressure in the eye damages the optic nerve. This is why it's so important that you consult your vet immediately when any signs of eye problems/injuries occur. If the pressure can be decreased within 24 hours of onset, there is a chance the vision may be saved in the affected eye. However, even if the pressure has been present for a considerable time and vision has been lost, the pain caused by the increased pressure is still severe.
Glaucoma in early stages can be recognised by a mild eye infection, excessive tearing, pain to the eye, squinting of the eye, sensitivity to light and cloudiness of the cornea. Glaucoma in a later stage can be recognized by the reddish color of the white (sclera) of the eye, an increase in the size of the eye or eyelids that do not close completely. In almost all cases, this is the stage glaucoma is diagnosed. Medication/surgery will be necessary to relieve the dog of this extreme pain. The vision can't be restored in the affected eye.
LCP - Leg Calve Perthes
LCP is the degeneration (decay) of the hip joint, specifically, the head of the femur (the "ball" of the joint). In LCP affected dogs, the femoral head first begins to degenerate and then heal - during the healing process the joint developes scar tissue inuced malformation and no longer fits cleanly into the hip socket, producing lameness and pain. The most common treatment for this disease is Femoral-Head Osteotomy - the removal of the ball of the hip joint. This eradicates pain and produces free movement of the leg. It is nor know exactly what causes LCP and there is no known genetic marker, and therefore no DNA test that can be performed to detect its presence LCP can be tested for using a hip x-ray but it most often detected in pups at 4-12 months of age by the onset of the disease and resultant pain, inflammation and lameness.
Hearing - baer
The Chinese Crested can have hearing troubles just like every other breed but it's not common.
VD - Vitreous Degeneration
Vitreous is a transparent, gelatinous matter what consists of 99% water and 1% solid elements (proteins, collagen filaments and hyaluronic acid molecules). The relationship between the formed elements and the ability of hyaluronic acid molecules to retain water molecules gives the vitreous its gel consistency.
When these hyaluronic acid molecules release their water molecules pockets of liquefied vitreous are being formed. The collagen filaments unite into collagen fibrils and the vitreous gel structure will loose the transparant condition.
When these hyaluronic acid molecules release their water molecules pockets of liquefied vitreous are being formed. The collagen filaments unite into collagen fibrils and the vitreous gel structure will loose the transparant condition.
Retinal Folds
Retinal folds rarely cause vision problems for the individual dog. They represent small blind spots which are probably not even noticed by the dog. However, large areas of dysplasia (geographic dysplasia) may lead to large deficits in the visual field and dogs with retinal detachments are completely blind.
Heart - Cardio
Heart problems are not very common in the Chinese Crested but they do occour in the breed.
Allergies
Like all breeds, the Chinese Crested dog can have allergies.
vWD - Von Willebrand Disease
vWDis the most common canine hereditary bleeding disorder and has been reported in over 50 different breeds of dogs. However, vWS is most prevalent in the Corgi, Doberman Pincher, German Shepherd Dog, German Shorthaired Pointer, Golden Retriever, Shetland Sheepdog and Standard Poodle.
Though not formerly considered an issue in the Chinese Crested breed, a small number of Cresteds have been diagnosed, largely thanks to the very broad testing panel provided by PawsitivelD/Pinpoint Technologies. vWD is caused by a deficiency in the amount of a protein needed to help platelets (a blood cell used in clotting) seal broken blood vessels. The deficient protein is called von Willebrand factor antigen. Dogs affected with vWD bleed and bruise easily, have difficulty ceasing bleeding when cut or injured and can suffer internal bleeding with injuries that would not otherwise affect a normal animal. This disease has a known genetic marker and can be tested for using DNA.
Though not formerly considered an issue in the Chinese Crested breed, a small number of Cresteds have been diagnosed, largely thanks to the very broad testing panel provided by PawsitivelD/Pinpoint Technologies. vWD is caused by a deficiency in the amount of a protein needed to help platelets (a blood cell used in clotting) seal broken blood vessels. The deficient protein is called von Willebrand factor antigen. Dogs affected with vWD bleed and bruise easily, have difficulty ceasing bleeding when cut or injured and can suffer internal bleeding with injuries that would not otherwise affect a normal animal. This disease has a known genetic marker and can be tested for using DNA.
Skin - Sun and Blackheads
If you think that by getting a hl dog, you are getting rid of all grooming, you are wrong. The hl Crested variety requires special care for its skin.
Although the hairless Chinese Crested does not have the typical "doggie" odor, regular bathing is important to keep its skin clean. The breed can get blackheads on its skin.
If the skin is too dry you may need to moisturize the skin (but be careful that you do not use anything with lanolin as it is not good for the Crested) or take a closer look to your dogs diet.
Like humans, the hairless Chinese Crested is susceptible to sunburn. Sunscreen should be applied to protect it from the sun if it is to hot. Note that the lighter the skin of the dog is, it's more prone to burn.
Although the hairless Chinese Crested does not have the typical "doggie" odor, regular bathing is important to keep its skin clean. The breed can get blackheads on its skin.
If the skin is too dry you may need to moisturize the skin (but be careful that you do not use anything with lanolin as it is not good for the Crested) or take a closer look to your dogs diet.
Like humans, the hairless Chinese Crested is susceptible to sunburn. Sunscreen should be applied to protect it from the sun if it is to hot. Note that the lighter the skin of the dog is, it's more prone to burn.