Health in Cotons
The Coton is generally a healthy breed. Following are some of the conditions that have been seen in Cotons, although they're not widespread in the breed. All our dogs are either CLEAR from their parents or have been tested.
Patella Luxation (PL) knees that slip in and out of place) are a common problem in any small breed, and the Coton is no exception. It's important to protect puppies from jumping on and off furniture while their joints are still developing. Cotons think they're invincible, as well as capable of flight, so it's important to protect them from themselves.
Hip Dysplasia (HD) - is a heritable condition in which the thighbone doesn't fit snugly into the hip joint. Some dogs show pain and lameness in one or both rear legs, but you may not notice any signs of discomfort in a dog with hip dysplasia. As the dog ages, arthritis can develop. X-ray screening for hip dysplasia is done by the Orthopedic Foundation for Animals (OFA). Dogs with hip dysplasia should not be bred. Hip dysplasia is hereditary, but it may sometimes be worsened by environmental factors, such as rapid growth from a high-calorie diet or injuries incurred from jumping or falling on slick floors.
Progressive Retinal Atrophy (PRA) is a hereditary degenerative eye disorder that eventually causes blindness from the loss of photoreceptors at the back of the eye. PRA is detectable years before the dog shows any signs of blindness. Fortunately, dogs can use their other senses to compensate for blindness, and a blind dog can live a full and happy life. Just don't make it a habit to move the furniture around. Reputable breeders have their dogs' eyes certified annually by a veterinary ophthalmologist and do not breed dogs with this disease.
Von Willebrand disease (vWD) is caused by plasmatic von Willebrand factor (vWF) insufficiency. VWF is a blood glycoprotein (not enzyme) important for blood coagulability.
Its primary function is to bind itself to other proteins (for example it stabilizes Factor VIII), and also facilitates aggregation and adhesion of the trombocytes to wound site. The deficiency or failure of vWF function causes bleeding which is most apparent in tissues having high blood flow shear in narrow vessels. VWD manifests oneself as a tendency to bleeding from skin and tissues. The disease can be inheritable or acquired.
Primary hyperoxaluria (PH) is a rare autosomal recessive disorder of glyoxylate metabolism in humans that was also described in dogs (Jansen &Arnesen 1990; Danpure et al. 1991, Vidgren et al. 2012) and cats (Goldstein et al. 2009). It is characterized by the accumulation of oxalate and subsequent precipitation of calcium oxalate crystals, primarily in the kidneys, leading to progressive kidney failure. If the storage capacity of the kidneys is exhausted, the crystals are accumulated in other tissues, for example in bones, joints, cartilages, retina and muscles.
Neonatal Cerebellar Ataxia is a neurological symptom consisting of a lack of normal coordination of movements. In case of neonatal ataxia the lack of normal coordination becomes evident soon after birth.
Neonatal ataxia was (BNAt – Bandera´s neonatal ataxia) originally called Bandera´s syndrome after the first puppy of Coton de Tulear breed affected, in which the clinical signs of this disease were described.
Degenerative myelopathy (DM) is a progressive neurodegenerative disease which occurs in wide range of dogs approximately at eight years of age. The widespread distribution of the mutation among the breeds suggests that it originated before diversification of the breeds. Affected dogs develop non-painful weakness of the pelvic limbs that causes problems with coordination and unsteady gait, than the signs slowly progress to muscle atrophy, ataxia, incontinence and ends with paralysis of hind limbs. The symptoms accompanying this disease are so severe that the dog dies within 3 to 5 years after occurrence of the first signs. However, the dog is euthanized approximately one year after symptoms first appear.
Canine multifocal retinopathy (CMR) is a hereditary disease. Most often affected dog breeds are: Great Pyrenees, English Mastiffs, Bullmastiffs, Coton de Tulear and related breeds.
CMR symptoms are very similar to Best macular dystrophy disease (BMD) in humans. BMD and CMR are retinal disorders caused by mutation in VMD2 gene (Vitelliform Macular Dystrophy 2 Gene). VMD2 gene is coding a protein bestrophin which is responsible for right forming of pigment epithelium in retina. Mutations in VMAD2 gene cause pigment epithelium athrophy which is leading to serious damage of sight.
Chondrodysplasia, chondrodystrophy and degeneration of intervertebral discs
Extremely shortened legs are a trait that defines many dog breeds. The reduced long bone length occurs as a consequence of abnormal growth of cartilage and early changes in the structure of growth plates and their premature calcification that result in shortened leg bones with bowed appearance. Currently, two conditions causing these short-legged phenotypes (or disproportional dwarfism) are known – chondrodysplasia and chondrodystrophy.
Chondrodysplasia is caused by insertion of retrogene encoding fibroblast growth factor 4 (FGF4) in dog chromosome 18 that is involved in many biological processes incl. bone development. It occurs in breeds such as Basset Hound, Welsh Corgi, Dachshund, West Highland White Terrier and Scottish Terrier. The inheritance of this mutation is considered to follow an autosomal dominant mode. This means that this phenotype is expressed when a dog obtains only one allele from one of its parents.
The mutation causing chondrodystrophy has been discovered recently as a second FG4-retrogene insertion in dog chromosome 12. This mutation explains a short-legged phenotype in other dog breeds such as Jack Russel Terriers, Dandie Dinmont Terriers, French Bulldogs, Chihuahua, Chinese Crested, Pekingese, Shih Tzu, Havanese, Coton de Tulear, Bishon Frise, Miniature and Toy Puddle, Beagle, Cavalier King Charles Spaniel, English Springer Spaniel, American Cocker Spaniel, Portuguese Water Dog, Nova Scotia Duck Tolling Retriever or Chesapeake Bay Retriever. Dogs that carry both mutations show a more drastic reduction of leg length. The affected breeds are in particular Basset Hounds, Dachshund, Welsh Corgi and Scottish terriers.
Beside the reduction of the leg length the insertion in chromosome 12 is also connected with predisposition to abnormal growth and development of intervertebral discs. In affected dogs, premature calcification at early age (from birth to 1 year of age) results in loss of flexibility and gradual degeneration of intervertebral discs. These abnormal discs are predisposed to herniation into the spinal canal where the inflammation and haemorrhage can cause severe pain and neurological dysfunction termed Intervertebral Disc Disease of type I (IVDD). IVDD has high mortality rate and high cost of surgical and medical veterinary care.
To the breeds at high risk for IVDD belong Dachshunds, Welsh Corgi, Pekingese, Shih Tzu, Cocker Spaniel, French Bulldog and Beagle.
The mutation for chondrodystrophy is inherited as a semi-dominant trait for height, meaning that dogs with 2 copies of the mutation are smaller than dogs with only 1 copy. As to predisposition to degeneration of intervertebral discs, the inheritance follows an autosomal dominant mode meaning that 1 allele obtained from one of its parents is sufficient to expressing the phenotype.
Genetic testing for these mutations can help breeders determine if CDDY is present among breeding stock and to identify dogs at risk for IVDD. In breeds where both mutations are present, breeders can benefit from test results to implement breeding strategies to reduce incidence of CDDY, while retaining the short-legged phenotype conferred by CDPA.
More information and DNA tests can be ordered from Genomia Genetic Laboratory https://www.genomia.cz/en/breed/coton-de-tulear/
Source: Genomia Genetic Laboratory