Collie eye anomaly [ In Eyes ]
Collie eye anomaly (CEA) is a congenital, inherited, bilateral eye disease of dogs involving the retina, choroid, and sclera. It can be a mild disease or cause blindness. It is known to occur in Smooth and Rough Collies, Shetland Sheepdogs, Australian Shepherds, Border Collies, and Nova Scotia Duck Tolling Retrievers.

Congenital diaphragmatic hernia [ In Miscellaneous ]
Congenital diaphragmatic hernia is uncommon in dogs. Most diaphragmatic hernias are caused by trauma. Congenital diaphragmatic hernias are usually communications between the peritoneum and pericardium. They are often incidental findings.  

Congenital vertebral anomalies [ In Skeletal and Muscular Disorders ]
Congenital vertebral anomalies, including butterfly, block, and transitional vertebrae, and hemivertebrae, are a collection of malformations of the spine in animals. Most are not clinically significant, but they can cause compression of the spinal cord by deforming the vertebral canal or causing instability.

Congestive heart failure [ In Cardioascular and Circulatory ]
Congestive heart failure is any heart disease that results in the inability to put out enough blood to meet the dog's needs. It can be caused by the above two diseases, heat stroke, electric shock, injury, infection, developmental heart defects, or high blood pressure. Signs depend on which side of the heart is affected. Left-sided heart failure may result in coughing and difficulty breathing from a build-up of fluid in the lungs (pulmonary edema) and fainting. Right-sided heart failure may result in a build-up of fluid in the abdomen (ascites), fluid around the lungs (pleural effusion), or peripheral edema.

Conjunctivitis [ In Eyes ]
Conjunctivitis is inflammation of the conjunctiva. In dogs it is most commonly caused by mechanical irritation (such as by entropion, ectropion, or trichiasis), allergies, and keratoconjunctivitis sicca. Any bacterial infection is usually secondary.

Coonhound paralysis [ In Nervous System ]
Coonhound paralysis is a type of polyradiculoneuritis seen in Coonhounds. The cause has been related to a raccoon bite. Signs include rear leg weakness progressing rapidly to paralysis, and decreased reflexes.

Coprophagia [ In Behavioral ]
Coprophagia is the ingestion by a dog of feces, either its own or those of another dog or animal. It can be caused by medical conditions such as exocrine pancreatic insufficiency, overfeeding, or malabsorption. It can also be a behavioral problem characterized by attention-seeking, reinforcement, or as a learned behavior. Numerous health problems can arise from this activity, including internal parasites or infection with canine parvovirus or toxoplasmosis. Treatment includes behavioral modification therapy or altering the feces to affect its taste.

Cor triatriatum [ In Cardioascular and Circulatory ]
Cor triatriatum, specifically cor triatriatum dexter, occurs in dogs and is characterized by a fibrous division of the right atrium. It can be treated by balloon valvuloplasty.

Corneal dystrophy [ In Eyes ]
Corneal dystrophy is a condition characterized by bilateral, noninflammatory opacity of the cornea. It appears as grayish white lines, circles, or clouding of the cornea. Corneal dystrophy can also have a crystalline appearance.

Corneal ulcer [ In Eyes ]
Corneal ulcer, or ulcerative keratitis, is an inflammatory condition of the cornea involving loss of its outer layer. They are caused by trauma, detergent burns, and infections. Other eye conditions can cause corneal ulcers, such as entropion, distichia, corneal dystrophy, and keratoconjunctivitis sicca.

Craniomandibular osteopathy [ In Skeletal and Muscular Disorders ]
Craniomandibular osteopathy is a hereditary disease in West Highland White Terriers and also occurs in other terrier breeds. It is a developmental disease in puppies causing extensive bony changes in the mandible and skull. Signs include pain upon opening the mouth.

Cryptococcosis [ In Fungal Infections ]
Cryptococcosis is a fungal disease caused by Cryptococcus neoformans that affects both dogs and humans. It is a rare disease in dogs, with cats seven to ten times more likely to be infected. The disease in dogs can affect the lungs and skin, but more commonly the eye and central nervous system.

Cryptorchidism [ In Urinary and Reproductive Systems ]
Cryptorchidism is when one the testicles is retained in the abdomen or inguinal canal past a normal stage of development. It is a common occurrence in dogs and is thought to be a sex-limited autosomal recessive trait.

Cushing's syndrome [ In Endocrine Diseases ]
Cushing's syndrome, also known as hyperadrenocorticism, is a condition characterized by an increase in glucocorticoids secreted by the adrenal glands. About 85 percent of cases are caused by a tumor in the pituitary gland, while 15 percent are caused by an adrenal tumor. Signs include increased appetite, increased drinking and urination, a pot-bellied appearance, muscle weakness, and lethargy. Diagnosis can be difficult as there are no tests with both high sensitivity and specificity. Treatments inclulde mitotane, trilostane, ketoconazole, or selegiline. Surgery is used in some cases of adrenal tumors.

Dancing Dobermann disease [ In Nervous System ]
Dancing Dobermann disease is a type of myopathy that primarily affects the gastrocnemius muscle in Dobermanns. It usually starts between the ages of 6 to 7 months. One rear leg will flex while standing. Over the next few months it will begin to affect the other rear leg.