Animalia Life

The Breed History
The ancestor of this small spaniel is recorded in tapestry and art in the 15th century; a Toy spaniel was perhaps a luxury item for aristocrats since this was definitely a non-hunting dog. They were the chosen dogs of the Court of King Charles I and II and at this point in this line of dogs, the name was given as King Charles spaniel. In the time of Queen Victoria, a short nosed dome skull type was preferred, and the old type fell out of favor. In the USA, type reflected the old longer-muzzled low stop version of the Toy spaniel of Charles II time, and that variant is now recognized by the old name of English Toy spaniel. In Britain, a return to the long-faced variety that more closely resembled the spaniels in old paintings was bred, and the classic type was accepted into registration as the Cavalier King Charles spaniel to distinguish it from the short-nosed King Charles. It was first registered in AKC 1962 in the Miscellaneous
class, but full recognition occurred in 1996, at which time they were assigned to the Toy group.

Breeding for Function
Bred for companionship. They are suitable for obedience trials as well.

Physical Characteristics
Height at Withers: female 12-13" (30.5-33 cm), male 12-13" (30.5-33 cm).
Weight: females 13-17lb ( 6-7.5 kg) , males 14-18 lb ( 6-8 kg).
Coat: The silky, soft, slightly wavy moderately long coat is lightly feathered. Blenheim color is a white dog with chestnut markings and a specific chestnut mark on the forehead in a white blaze is favored (Blenheim mark). Other colors include tri-color in red, white and black. Ruby, a red solid, and black and tan are other coat color variants.
Longevity: 9-14 years.
Points of Conformation: They have very soft expressions, and their large dark brown eyes are set wide apart on a broad face. The skull is not domed and a moderate stop is present, the nose is large, square and black. The ears are pendulous and feathering is moderate. Slightly longer than tall, they are moderately boned, and the neck is long and slightly arched. The topline is level and chest is moderately deep with ribs well sprung. Their tail may be docked. It is held level with the topline or a bit lower. They possess straight legs and compact feet, and dewclaws may be removed. Their movement is smooth and low, and straight with long strides.

Recognized Behavior Issues and Traits
The dog is a devoted, intelligent, playful and friendly dog. They need to be in an environment with lots of human contact. They enjoy the company of children and other pets. They are active and require average exercise. They have a well-developed chase instinct, so must not be off-leash unless in an enclosure. They are moderate shedding dogs and require regular levels of grooming. It is helpful to trim around the paws to help prevent matting. They are known as the perfect lap dog. They are alarm barkers.

Normal Physiologic Variations
AsymptomaticThrombocytopenia/Macrothrombocytopenia: Cavalier King Charles spaniels (CKCS) often have idiopathic asymptomatic thrombocytopenia (< 100,000 platelets/microL). In affected dogs, the thrombocytes are often large. Platelet mass (plateletcrit) is a better measurement of platelet function in the breed. The condition is due to an autosomal recessive mutation in the beta1-tubulin gene. A genetic test is available.
Temporomandibular Joint Dysplasia: Temporomandibular joint dysplasia is a widespread asymptomatic condition in the breed and should be regarded as a normal morphologic variation rather than a pathologic anomaly.

Drug Sensitivities
None reported

Inherited Diseases
Hip Dysplasia and Legg-Calve Perthes Disease: Polygenically inherited traits causing degenerative hip joint disease and arthritis. OFA reports 12.1% affected. Reported at a frequency of 4.2% in the ACKCSC, Inc. Health Survey 2004-2005.
Patella Luxation: Polygenically inherited laxity of patellar ligaments, causing luxation, lameness, and later degenerative joint disease. Treat surgically if causing clinical signs. Reported 9.1x odds ratio versus other breeds. OFA reports 2.3% affected. Reported at a frequency of 6.2% in the ACKCSC, Inc. Health Survey 2004-2005.
Elbow Dysplasia: Polygenically inherited trait causing elbow arthritis. OFA reports 0.7% affected.
Episodic Collapse (Paroxysmal Hypertonicity, Hyperexplexia): Autosomal recessive disorder in the breed. Collapse with increased limb extensor tone triggered by excitement and characterized by a brief period of bunny hopping with the head held down and the rear end raised. Affected dogs may show signs starting at three months of age. Treatment is with clonazepam. The condition resolves over time in some dogs. A genetic test is available.
Muscular Dystrophy: X-linked recessive muscular dystrophy due to a mutation in the dystrophin gene has been identified in the breed. Affected dogs show clinical signs from a few months of age, including weakness, muscle atrophy, exercise intolerance, dysphagia and macroglossia (enlarged tongue). Serum creatine kinase is usually markedly elevated. Male dogs with the mutation are clinically affected and female dogs with the mutation are silent carriers. Affected males with the same mutation have been identified in the UK and the USA.
Congenital Keratoconjunctivitis Sicca (KCS) and Ichthyosiform Dermatosis: Rare autosomal recessive, congenital disorder in the breed of lack of tear production and scaly skin. In affected dogs, the coat appears curly at birth, and the skin deteriorates as the dog matures. The eye condition is treatable with lubricants. A genetic test is available.

Disease Predispositions
Chronic Mitral Valve Disease/Mitral Prolapse: Systolic heart murmurs caused by chronic mitral valve disease are common in the breed, with an average age of diagnosis of 6.25 years. Left atrial enlargement, and not heart enlargement, should be used to evaluate the heart size and indirectly the severity of mitral regurgitation on radiographs. Left atrial enlargement is found to occur only in the last year prior to congestive heart failure. Echocardiographic studies suggest that mitral regurgitation and prolapse may be present in most affected dogs by 5 years of age. Predisposition may be related to serotonin (5HT) metabolism. Heritability estimates of 0.67 for the grade of murmur and 0.33 for the presence/absence of murmur have been calculated in the breed. Heart murmurs are reported at a frequency of 30.7%, and mitral valve disease at 27.0% in the ACKCSC, Inc. Health Survey 2004-2005. Mode of inheritance has not been determined.
Chiari-like Malformation (Occipital Bone Hypoplasia): This condition is characterized by a shortening of the basicranium and supra-occipital bone with a compensatory lengthening of the cranial vault, especially the parietal bone. CM can be diagnosed with MRI. CM can strongly predispose, but is not necessary for the brain disease syringomyelia.
Pancreatic Acinar Atrophy (Exocrine Pancreatic Insufficiency): Cavalier King Charles Spaniels are found to have an increased incidence of for immune-mediated pancreatic acinar atrophy. Clinical signs are poor weight gain, and steatorrhea. One study in the UK found a prevalence of 26.3%. Median age of onset is 6 years. Treat with pancreatic enzyme supplementation. Breeding studies suggest an autosomal recessive mode of inheritance in German shepherd dogs, another breed found at risk.
Brachycephalic Complex: Includes elongated soft palate, stenotic nares, hypoplastic trachea, and everted laryngeal saccules. Causes dyspnea, and can cause collapse and death with extreme stress. Identified in 20.5% of Cavalier King Charles spaniels in an Australian study. Surgery is indicated in severe cases.
Umbilical Hernias: Congenital inherited umbilical hernias are reported at 12.1% in the ACKCSC, Inc. Health Survey 2004-2005.
Retinal Dysplasia: Focal retinal dysplasia with retinal folds is reported in 9.30%, and geographic retinal dysplasia is reported in 3.18% of Cavalier King Charles spaniels CERF examined by veterinary ophthalmologists between 2000-2005. Severe cases can progress to retinal detachment. CERF does not recommend breeding any CKCS with retinal dysplasia. Reported at 3.0% in the ACKCSC, Inc. Health Survey 2004-2005.
Distichiasis: Abnormally placed eyelashes that irritate the cornea and conjunctiva. Can cause secondary corneal ulceration. Identified in 9.16% of Cavalier King Charles spaniels CERF examined by veterinary ophthalmologists between 2000-2005. Reported at 2.7% in the ACKCSC, Inc. Health Survey 2004-2005.
Corneal Dystrophy: The breed can have an epithelial/stromal form of corneal dystrophy. Age of onset 2-5 years. Identified in 8.24% of Cavalier King Charles spaniels CERF examined by veterinary ophthalmologists between 2000-2005. Reported at 2.7% in the ACKCSC, Inc. Health Survey 2004-2005.
Deafness: Can be congenital or progressive in the breed, and can be unilateral or bilateral. The progressive form results in deafness by 3-5 years of age. Diagnosed by BAER testing. Reported at 6.2% in the ACKCSC, Inc. Health Survey 2004-2005.
Cataracts: In the Cavalier King Charles spaniel, onset is at an early age (less than 6 months), affecting the cortex and nucleus with rapid progression to complete cataract, resulting in blindness. Punctate cataracts also occur. Reported in 3.90% of Cavalier King Charles spaniels presented to veterinary teaching hospitals. Identified in 2.98% of Cavalier King Charles spaniels CERF examined by veterinary ophthalmologists between 2000-2005. Reported at 6.0% in the ACKCSC, Inc. Health Survey 2004-2005. CERF does not recommend breeding any CKCS with a cataract.
Keratoconjunctivitis Sicca (KCS, Dry Eye): Ocular condition causing lack of tear production and secondary conjunctivitis, corneal ulcerations, and vision problems. Age of onset 2-5 years. Treat with topical ocular lubricants and anti-inflammatory medication. Reported at 5.3% in the ACKCSC, Inc. Health Survey 2004-2005.
Allergic Dermatitis: Presents with pruritis and pyotraumatic dermatitis (hot spots). Inhalant allergies were identified in 5.0%, Food Allergy was identified in 3.5%, and Hot Sports were identified in 4.8% of Cavalier King Charles spaniels in the ACKCSC, Inc. Health Survey 2004-2005.
Sebaceous Cysts: Benign sebaceous skin cysts are reported at 5.0% in the ACKCSC, Inc. Health Survey 2004-2005.
Syringomyelia (SM): Syringomyelia is a condition where fluid filled cavities develop within the spinal cord. The majority of affected dogs do not show clinical signs. Morphological variation of the atlantoaxial spine found in the breed does not correlate to the occurrence of SM. Chiari-like malformation (CM) is a predisposing factor, but not always present with SM. Crowding of the caudal cranial fossa can be a predisposing factor for developing SM. Ultrasonography through the atlantoccipital junction can identify cerebellar herniation through the foramen magnum, but not a syrinx. Clinical signs of SM can present usually between 5 months and 3 years of age, and include persistent scratching at the shoulder region with apparent neck, thoracic limb, or ear pain and thoracic limb lower motor neuron deficits. Diagnosis is by MRI. The size of the syrinx on MRI, and dorsal horn location are positively correlated to the amount of pain exhibited. Corticosteroid or NSAID treatment can improve, but not resolve the clinical signs. The percentage of Cavalier King Charles Spaniels in the general population with an MRI identified syrinx is not determined, but is expected to be high. Clinical signs of SM are reported at 3.9% in the ACKCSC, Inc. Health Survey 2004-2005. One study computed a heritability of 0.37, with the influence of multiple genes involved.
Intervertebral Disc Disease (IVDD): Cavalier King Charles spaniels have an increased risk of developing spinal cord disease due to prolapsed disk material. Clinical signs include back pain, scuffing of paws, spinal ataxia, limb weakness, and paralysis. Reported at 3.2% in the ACKCSC, Inc. Health Survey 2004-2005.
Chronic Pancreatitis: Often subclinical inflammation of the pancreas that can cause intermittent discomfort and gastrointestinal upsets, and can possibly lead to pancreatic insufficiency or diabetes mellitus. Cavalier King Charles spaniels have a 3.2x relative risk versus other breeds.
Idiopathic Epilepsy: Generalized or parital seizures. Control with anti-seizure medication. Seizures are reported at a frequency of 3.0% in the ACKCSC, Inc. Health Survey 2004-2005. Unknown mode of inheritance.
Femoral Artery Occlusion/Aortic Thromboembolism: Observed in 2.3% Cavalier King Charles spaniels examined. Femoral artery occlusion is not clinically important in dogs because of adequate collateral circulation. The higher frequency in the breed may be due to a primary femoral artery abnormality, or secondary to thrombus formation from heart disease.
Hypothyroidism: Inherited autoimmune thyroiditis. 2.2% positive for thyroid auto-antibodies based on testing at Michigan State University. (Ave. for all breeds is 7.5%).
Persistent Pupillary Membranes: Strands of fetal remnant connecting; iris to iris, cornea, lens, or involving sheets of tissue. The later three forms can impair vision, and dogs affected with these forms should not be bred. Identified in 1.62% of Cavalier King Charles Spaniels CERF examined by veterinary ophthalmologists between 2000-2005.
Eosinophilic Disease: The breed may have a predisposition to eosinophilic disorders. Several case reports of unrelated Cavalier King Charles spaniels with eosinophilic stomatitis, enteritis, bronchopneumonopathy, or oral granulomas are reported. All responded to corticosteroid therapy.
Xanthinuria, Xanthine Urolithiasis: Several affected Cavalier King Charles spaniels have been reported with urethral obstruction and renal insufficiency. Xanthinuria is caused by an inherited deficiency of the enzyme xanthine oxidase. An autosomal recessive mode of inheritance is suggested.
Primary Secretory Otitis Media: Affected dogs had moderate to severe head or cervical pain and/or neurological signs. A bulging, but intact, tympanic membrane is found in most cases with a viscous mucus plug filling the middle ear on myringotomy. Treatment consists of repeated removal of the mucus plug, flushing of the middle ear, and local and systemic medical therapy. Tympanostomy tubes may be helpful for chronic recurrent cases. The disorder must be differentiated from syringomyelia in the breed.
Fly Catching Behavior: Behavioral disorder identified in the breed with classic clinical signs as if watching, and then catching a fly. Some affected dogs may behave as if their ears or feet are irritated, and some may also chase their tail. Fly catching has previously been classified as a complex partial seizure, however non-responsiveness to anticonvulsants makes it more likely that this is a compulsive disorder.
Diabetes Mellitus: Caused by a lack of insulin production by the pancreas. Controlled by insulin injections, diet, and glucose monitoring. Cavalier King Charles spaniels have a 1.45x risk of developing the disorder. However, members of the breed with a specific IL-10 allele have a 4.05x risk of developing the disorder. Unknown mode of inheritance.
Immunoglobulin Deficiency with Pneumocystis Pneumonia: Cavalier King Charles spaniels can have a defect in immunity that makes them susceptible to infection with pneumocystosis. IgG concentrations are lower, and IgM concentrations are significantly higher in the affected dogs.
Microphthalmia: Congenital disorder of a small eye (globe) associated with cataract, and posterior lenticonus. Identified in 0.11% of Cavalier King Charles spaniels CERF examined by veterinary ophthalmologists between 2000-2005. CERF does not recommend breeding any CKCS with this condition.
Brachgnathism, Hydrocephalus, Mitochondrial Myopathy, Prognathism, Progressive Retinal Atrophy, Renal Dysplasia, and Wry Mouth are reported.
Isolated Case Studies
Bilateral Renal Agenesis: Two one-day-old littermates were found to have a complete absence of both kidneys. Littermates and the parents had normal kidneys.
Ventricular Septal Defect (VSD): A ventricular septal defect was diagnosed in a 3-month-old male Cavalier King Charles spaniel and corrected surgically.
Juvenile Masticatory Muscle Myositis: Three of four 12-week-old cavalier King Charles spaniel littermates presented with difficulty in opening the mouth. Diagnosis was established immunohistochemistry and histopathology. Corticosteroid treatment resolved the condition in all the affected pups.
Organic Aciduria with Seizures: A 6-month-old, female Cavalier King Charles spaniel exhibited seizures due to an organic aciduria with excessive excretion of hexanoylglycine. Cluster seizures were controlled with anticonvulsants.

Genetic Tests
Tests of Genotype: Direct test for coat color alleles is available from Healthgene and VetGen.
Direct tests for Episodic Collapse and KCS/Ichthyosiform Dermatitis are available from the Animal Health Trust.
Direct test for Macrothrombocytopenia is available from Auburn Univ.-Boudreaux Lab.
Tests of Phenotype: CHIC Certification: Required testing includes hip radiographs, CERF eye examination (at 8-12 weeks, follow up at 12 months, annually until 5 years old, every two years until 9 years old), patella examination, and cardiac evaluation (by a cardiologist, preferably annually). (See CHIC website; caninehealthinfo.org.)
CKCSC Clear Heart Recommendations: Only breed dogs without a murmur at 2-1/2 years of age, whose parents both do not have a murmur at 5 years of age. "Heart clear" dogs are listed in the CKCSC Health Registry ckcsc.org.
Recommend BAER hearing test, elbow radiographs, thyroid profile including autoantibodies, and MRI for SM.

Miscellaneous
- Breed name synonyms: King Charles Spaniel, Cavalier, Cav, Charlies
- Registries: AKC, CKC, UKC, KCGB (Kennel Club of Great Britain), ANKC (Australian National Kennel Club), NKC (National Kennel Club)
- AKC rank (year 2008): 25 (7,626 dogs registered)
- Internet resources: American Cavalier King Charles Spaniel Club, Inc.: ackcsc.org
Cavalier King Charles Spaniel Club-USA: ckcsc.org
Cavalier King Charles Spaniel Club of Canada: cavaliercanada.com
Cavalier King Charles Spaniel Club-UK: thecavalierclub.co.uk