Animalia Life

The Breed History
In China about 150 BC, art depicts a Spitz type dog such as this, but it is likely the breed developed earlier in time. History records the presence of these types of dogs during the Tartar invasion of China about 1000 BC. Perhaps the Siberian Husky and Tibetan Mastiff were the breed progenitors or were offshoots from this breed. The name chow chow is a generic shipping term for "such and such" in the cargo hold, also chow may derive from chou, Chinese for edible. Whatever the real meaning, the dogs were given this nickname. They were first brought to England in the year 1880. The AKC admitted the breed in 1903.

Breeding for Function
The Chow has fulfilled many roles over the centuries including hunting by scent for pheasant and other game, companionship, livestock guard dog, pulling loads, producer of fur for clothing, and in China, as a food source.

Physical Characteristics
Height at Withers: 17-20" (43-51 cm)
Weight: 45-70 lb (20-32 kg)
Coat: The double coat is present in two varieties: a short smooth coat and a longer rough coat that stands out. The latter is much more common. Short-coated dogs have a distinct undercoat and the outer coat is dense, hard, and smooth in texture and no feathers or ruff are evident. Colors are solid to solid with shading. Colors accepted include red, black, blue, cinnamon and cream. Whites are very rare. Longevity: 11-12 years.
Points of Conformation: The Chow has an arctic type with a square strong broad build and compact conformation. The blue tongue and compressed scowling face characterize the breed. The bone is also heavy, muscling moderate and the haircoat is profuse. The head is broad and flat, and the muzzle is blocky. He possesses a high head carriage, and the oblique almond-shaped eyes are deep and wide set with dark brown color. They have tight darkly pigmented palpebral margins. Ears are pricked, small and the leather is moderate in thickness, with slightly rounded tips. On the face, one sees a moderate stop, brows well developed, and the large black nose has well opened nostrils. A slate nose may be present in blue coat colored chows. Lip margins, and all oral cavity membranes are black and the tongue is blue-black. The neck is full, well muscled and arched, the topline is straight and level, and ribs are well sprung. Limbs are straight, dewclaws may be removed, and feet are compact and sit on well-knuckled toes. A broad pelvis is evident. The tail is well feathered. The long rough coated dogs possess a well-developed ruff, especially in males (sometimes referred to as lion-like). The tapered tail is set high and carried over the back and covered with a profusion of hair. The normal gait is stilted due to the conformation of the rear limbs (straight through both tarsus and stifle).

Recognized Behavior Issues and Traits
Reported attributes of the breed include: Independent, dignified, confident, willful, high intelligence, can be aggressive to other dogs and small pets, aloof with strangers and may attack due to their guarding heritage. Overall, on average have dominant personalities. Their eye placement may trigger defensive responses due to their inability to access the full visual field; may be snappy and will bite if provoked, can tend to be a one-person dog. Early obedience is important, and early socialization is essential to discourage the aforementioned tendencies in some dogs. Should be raised with children or socialized thoroughly and children should be taught how to treat the dog. They need daily grooming to maintain a good coat. These are high shedding dogs. They have moderate exercise needs and are easily housebroken, and have a low doggy odor. They are considered good alarm barkers. They do not tolerate heat and humidity well.

Normal Physiologic Variations
Lip margins, and all oral cavity membranes are black and the tongue is blue-black.
A study in the UK shows 28.1% of litters are born via C-section.

Drug Sensitivities
None reported

Inherited Diseases
Elbow Dysplasia: Polygenically inherited trait causing elbow arthritis. OFA reports 47.6% affected. Found at a higher incidence than reported by the OFA in South Africa. Reported 16.6x odds ratio for fragmented coronoid process, 13.3x odds ratio for ununited anconeal process forms of elbow dysplasia, and 108.8x odds ratio for elbow osteochondrosis versus other breeds.
Hip Dysplasia: Polygenically inherited trait causing degenerative joint disease and hip arthritis. Reported 5.4x odds ratio versus other breeds. OFA reports 19.6% affected.
Patella Luxation: Polygenically inherited laxity of patellar ligaments, causing luxation, lameness, and later degenerative joint disease. Treat surgically if causing clinical signs. Reported 6.1x odds ratio versus other breeds. OFA reports 11.4% affected.
Congenital Myotonia: Rare, autosomal recessive congenital disorder that causes hindlimb ataxia, a stiff gait, and occasional collapsing. The severe muscle stiffness regresses with exercise. Treatment is with procainamide.

Disease Predispositions
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. Severely affected Chow Chows can be temporarily or permanently blind due to adherence to the cornea or lens. Dorn reports a 3.89x odds ratio versus other breeds. Identified in 46.45% of Chow Chows CERF examined by veterinary ophthalmologists between 2000-2005, with 45.16% iris to iris, 4.19% iris to cornea, and 1.29% iris to lens. CERF does not recommend breeding any Chow-Chows with the later two categories of PPM.
Entropion: A rolling in of the eyelids that can cause corneal irritation and ulceration. It is reported in 39.35% of Chow Chows CERF examined by veterinary ophthalmologists between 2000-2005. Dorn reports a 14.64x odds ratio versus other breeds. CERF does not recommend breeding affected Chow Chows.
Hypothyroidism: Inherited autoimmune thyroiditis. 7.4% positive for thyroid auto-antibodies based on testing at Michigan State University. (Ave. for all breeds is 7.5%).
Pemphigus Foliaceus: The breed has an increased risk (12.3x odds ratio) of developing pemphigus foliaceus. Clinical signs include crusting lesions to the dorsal part of the muzzle and head, progressing to the body. Diagnosis is with biopsy.
Aggression: Chow Chows are significantly over represented in human bite cases with a 4.0x odds ratio versus other breeds.
Primary (Narrow Angle) Glaucoma: Ocular condition causing increased pressure within the eyeball, and secondary blindness due to damage to the retina. Primary glaucoma in the breed is a bilateral condition due to narrow iridocorneal angles, with an age of onset of 3-6 years. One study shows 4.70% Chow Chows affected. A female preponderance occurs in the breed. Monitor with gonioscopy and tonometry. Dorn reports a 1.35x odds ratio versus other breeds. CERF does not recommend breeding affected Chow Chows.
Cranial Cruciate Ligament Rupture: The Chow Chow has a predisposition for cruciate ligament rupture, due to its straight hind leg conformation. Treatment is with surgery.
Corneal Dystrophy: Chow Chows have been identified with both the epithelial/stromal and endothelial forms of corneal dystrophy. Identified in 1.94% of Chow Chows CERF examined by veterinary ophthalmologists between 2000-2005. CERF does not recommend breeding affected Chow Chows.
Exposure Keratopathy Syndrome: Corneal reactivity and drying from ocular exposure secondary to shallow orbits, exophthalmos, and lagophthalmos. Identified in 1.61% of Chow Chows CERF examined by veterinary ophthalmologists between 2000-2005.
Ectropion: Ectropion, a rolling out of the eyelids, can cause frequent conjunctivitis, and ocular discharge. It is reported in 1.61% of Chow Chows CERF examined by veterinary ophthalmologists between 2000-2005.
Chronic Superficial Keratitis (Pannus): Chronic corneal inflammatory process that can cause vision problems due to corneal pigmentation. Treatment with topical ocular lubricants and anti-inflammatory medication. Identified in 1.29% of Chow Chows CERF examined by veterinary ophthalmologists between 2000-2005.
Cataracts/Congenital Cataracts with Ocular Anomalies: Inherited disorder causing congenital cataracts, sometimes associated with wandering nystagmus, entropion, microphthalmia, persistent pupillary membrane remnants, and multifocal retinal folds. Unknown mode of inheritance. Cataracts are identified in 1.29% of Chow Chows CERF examined by veterinary ophthalmologists between 2000-2005. CERF does not recommend breeding any Chow Chow with a cataract.
Alopecia-X (Black Skin Disease, BSD, Coat Funk): Progressive, symmetrical, non-pruritic, truncal hair loss usually beginning in early adulthood. ACTH, LDDS, and thyroid panel results are normal. Oral trilostane reverses the condition in some cases. The disorder appears to be familial.
Sebaceous Adenitis: Disorder of immune mediated sebaceous gland destruction, presenting with hair loss, hyperkeratosis and seborrhoea, usually beginning with the dorsal midline and ears. Diagnosis by skin biopsy. Treat with isotretinoin. Reported at an increased frequency in the breed.
Gastric Carcinoma: Chow Chows have the highest frequency of gastric carcinoma compared with other breeds. The most frequent clinical features are vomiting, polydipsia and weight loss, with endoscopic findings of a large deep ulcer with thickened, irregular rims and walls.
Gastric Dilatation-Volvulus (bloat, GDV): Polygenically inherited, life-threatening twisting of the stomach within the abdomen. Requires immediate treatment. Reported at an increased frequency in the breed.
Oral and Lingual Melanoma: Chow Chows have a higher incidence of oral melanomas versus other breeds. One study found a 7.89x relative risk versus other breeds. The gingival, labial mucosa, and tongue are the most common sites. Average age of onset is 11.4 years.
Pulmonic Stenosis: Congenital malformation of the pulmonic valve. Causes stricture of the right ventricular outflow tract or stricture of the pulmonary artery. Screen with auscultation and echocardiography. The Chow Chow has a 2.2x odds ratio for the condition versus other breeds. Unknown mode of inheritance.
Atrioventricular Block (AVB): Chow Chows are predisposed to high-grade second- or third-degree AVB. Weakness, lethargy, exercise intolerance, and syncope were the most common clinical signs. Recommended treatment is pacemaker implantation.
Pancreatic Acinar Atrophy (Exocrine pancreatic insufficiency): Chow Chows are a breed at risk for immune-mediated pancreatic acinar atrophy. Clinical signs are poor weight gain, and steatorrhea. Treatment is with enzyme supplementation. Breeding studies suggest an autosomal recessive mode of inheritance in German shepherd dogs, another breed found at risk.
Familial Juvenile Renal Disease: Kidney disorder seen in young Chow Chows causing classical polyuric, azotemic renal failure with anemia. Pathology includes interstitial fibrosis, small glomeruli, and lack of inflammatory cells. Unknown mode of inheritance.
Atresia Ani (Imperforate Anus): An increased incidence of this congenital condition is reported in the breed, with a frequency of 0.043%, and an odds ratio of 8.90x. Treatment is surgery.
Dysmyelination of the Central Nervous System: Rare, inherited congenital disorder causing whole body tremors. Affected dogs can survive with clinical signs. Unknown mode of inheritance.
Cervical Vertebral Instability, Color Dilution Alopecia, Dermatomyositis, Diabetes Mellitus, Epilepsy, Hypoadrenocorticism, IgA Deficiency, Keratoconjunctivitis Sicca, Osteocondritis Dessicans - Stifle, Progressive Retinal Atrophy, Tyrosinase Deficiency, Uveodermatological Syndrome, and Ventricular Septal Defect are reported.

Isolated Case Studies
Bronchial Cartilage Dysplasia: A 5-month-old Chow Chow that had exercise intolerance, progressive dyspnea, and episodic cough was diagnosed with bronchial cartilage dysplasia and secondary lobar bullous emphysema.
Ciliary Dyskinesia: A Chow Chow was diagnosed with congenital cliliary dyskinesia resembling Kartagener’s syndrome. Ciliary ultrastructure was normal, with poor ciliary function. Clinical signs are chronic respiratory infections.
Dermoid Sinus: A case report described multiple dermoid sinuses in the dorsal cervical and craniothoracic regions in an adult chow chow dog. One sinus did not open on the skin surface.

Genetic Tests
Tests of Genotype: Direct test for coat color is available from VetGen.
Tests of Phenotype: CHIC Certification: Required tests are; CERF eye examination, hip and elbow radiographs, thyroid profile including autoantibodies, and patella evaluation. (See CHIC website: caninehealthinfo.org)
Recommend cardiac evaluation.

Miscellaneous
• Breed name synonyms: Chow, Chinese Chow, local nicknames include "Black tongue" and "Black mouth dog" in Chinese. Other Chinese names are lang kou (wolf dog) and hsiung kou (bear dog)
• Registries: AKC, UKC, CKC, KCGB (Kennel Club of Great Britain), ANKC (Australian National Kennel Club), NKC (National Kennel Club)
• AKC rank (year 2008): 66 (1,359 dogs registered.)
• Internet resources: Chow Chow Club Inc.: chowclub.org
Chow Chow Fanciers of Canada: chowcanada.ca
The Chow Chow Club (UK): thechowchowclub.co.uk
Chow Health Website: chowhealth.org