Genetic
Health of Rhodesian Ridgebacks |
This information is designed
to elucidate the known genetic diseases associated with Rhodesian
Ridgebacks to enthusiasts of the breed. The aim is to educate
owners and breeders in order to reduce the occurrence of genetically
inherited diseases such as Hypothyroidism and Dermoid Sinus among
others.
The breeder’s ethical responsibility
is to discuss dogs with defects or those that produce defects
and to appropriately breed away from such genetic traits. As an
owner of a Rhodesian Ridgeback, it is also your responsibility
to report the development of any genetic anomaly that presents
itself during the course of your dog’s lifetime to the breeder
of that dog. The breeders aim is to produce the healthiest and
most correct conformation puppy possible. This cannot be achieved
successfully without open knowledge of genetic problems that are
present within any line of Ridgebacks.
By developing pedigrees to illustrate
genetic inheritance the breeder is able to interpret the genetic
status of dogs used to produce a litter. This knowledge allows
the breeder to more carefully select breeding stock. Every Rhodesian
Ridgeback carries genes for approximately 6.6 genetic defects
which is similar to the amount of genetic defects you and I carry.
By knowing which 6.6 genetic defects are carried by a breeding
dog or bitch and breeding away from those defects is the key to
controlling genetic disease in Rhodesian Ridgebacks.
Adwera Rhodesian Ridgebacks is committed
to the welfare of our beloved breed. We are developing genetic
pedigrees and are committed to discuss them with other breeders
and to use them to improve the genetic quality of Rhodesian Ridgebacks.
If you are interested in beginning a genetic pedigree or would
like more information about control of genetic traits Adwera Rhodesian
Ridgebacks recommends the book “Control of Canine Genetic
Diseases” by Dr. George A. Padgett, DVM |
Disease
Name |
Description |
Megaesophagus
(Esophageal Achalasia) |
Clinical symptoms are regurgitation of
undigested food. This occurs due to the failure of esophageal muscles
to force swallowed food through to the stomach.
Mode of inheritance is undetermined
Age of onset < 6 mos. |
Hypothyroidism
(Autoimmune thyroiditis, Hashimoto’s Disease, Lymphocytic
thyroiditis) |
Destruction of the thyroid gland due to
an attack from the animal’s own immune system. Symptoms are
rough, scaly skin, hair loss, and weight gain.
Mode of inheritance is recessive
Age of onset is < 2 yrs. |
Deafness |
Inability to hear, may be unilateral or
bilateral.
Mode of inheritance is undetermined
Age of onset is < 6 mos. |
Alopecia
(Idiopathic Flank Alopecia or Cyclical Flank Alopecia) |
Clinical symptoms include hair loss on
flanks with little or no scaling or any inflammatory changes. Hyperpigmentation
may occur.
Mode of inheritance is undetermined
Age of onset < 5 yrs. |
Myotonia |
Muscles continue to contract after voluntary
movement ceases causing a stiff gait.
Mode of inheritance is recessive
Age of onset < 6 mos. |
Dermiod
Sinus (Arachnoid cyst, Meningeal cyst) |
Cavities or cysts may develop within the
meninges separated from the spinal cord by pia mater. They may compress
the cord.
Mode of inheritance is undetermined
Age of onset birth. |
Rhodesian
Ridgeback cerebellar degeneration and color dilution syndrome |
All affected puppies show coat color dilution
and cerebellar signs, including growth retardation, ataxia, inability
to stand and tremors.
Mode of inheritance is recessive
Age of onset < 4 wks. |
Cataracts |
Lens opacity that obscures vision and may
cause blindness.
Mode of inheritance is undetermined
Age of onset varies. |
Entropian |
Turning in of the eyelids causing the eyelashes
to rub the eyeball.
Mode of inheritance is undetermined
Age of onset is < 1 yr. |
Eversion
of the nicitating membrane (Eversion of the third eyelid) |
The cartlidge in the third
eyelid is abnormal, causing the third eyelid to roll away from or
toward the globe.
Mode of inheritance is undetermined
Age of onset < 3 mos. |
Pannus
(Superficial Stromal Keratitis) |
An epithelial growth over the cornea causing
a gray haze that may obscure vision.
Mode of inheritance is undetermined
Age of onset < 1 yr. |
Persistent
Pupillary Membranes (PPM Mesodermal dygenesis) |
A failure of blood vessels in the anterior
chamber of the eye to regress normally; there may be impaired vision
or blindness.
Mode of inheritance is undetermined
Age of onset < 3 mos. |
Progressive
Retinal Atrophy (PRA) |
Degeneration of the retinal vision cells
which progresses to blindness.
Mode of inheritance is undetermined
Age of onset varies |
Calcinosis
Circumscripta |
Abnormal deposits of calcium in the skin
and subcutaneous tissue.
Mode of inheritance is undetermined
Age of onset < 1 yr. |
Hemivertebra |
Abnormal formation of he body of the vertebrae,
which can cause posterior ataxia and paralysis.
Mode of inheritance is undetermined
Age of onset < 1 yr. |
Hip Dysplasia |
Abnormal formation of the hip socket; causes
rear-limb lameness.
Mode of inheritance is polygenic
Age of onset < 2 yrs. |
Osteochondritis
Dessicans (OCD) |
Aseptic necrosis of bone under joint cartlidge;
causes lameness.
Elbow Joint (Elbow Dysplasia): OCD of the medial humeral condyle,
fractured coronoid process and nonfusion of the anconeal process.
Mode of inheritance is polygenic
Age of onset < 1yr.
Shoulder joint Undetermined < 1 yr.
Tarsocrural Joint Undetermined < 1 yr. |
Spondylosis
Deformans |
Abnormal fusion or bridging between vertebrae,
may cause pain and/or paralysis.
Mode of inheritance is polygenic
Age of onset > 1 yr. |
Transitional
Vertebral Segments (Lumbosacral) |
Clinical signs associated with this disorder
relate to damage to the cauda equina and include paresis, paralysis,
denervation, atrophy and atonia.
Mode of inheritance is polygenic
Age of onset varies |
Wobbler
Syndrome (Cervical Spondylolisthesis, vertebral instability) |
Abnormality of the neck vertebrae causing
rear leg ataxia that may progress to paralysis. The main vertebrae
affected are 5, 6, and 7.
Mode of inheritance is polygenic
Age of onset < 1yr. |
Renal
Dysplasia |
Failure of normal development of the renal
parenchyma causing malfunction and death. Clinical signs are those
of renal failure.
Mode of inheritance is undetermined
Age of onset < 1 yr. |
