American cocker spaniels (and especially English cocker spaniels) have been reported with cases of congenital deafness. Most instances of congenital deafness are caused 3-4 weeks after birth due to the degeneration of blood supply to the inner ear or cochlea. This type of deafness is associated with white pigmentation (i.e. white hair, blue eyes) and is permanent. Congenital deafness may affect one or both ears. A puppy that fails to wake up during a loud noise is likely to have bilateral deafness. The brain stem auditory evoked response (BAER) test is used to diagnose deafness in dogs. Bilaterally deaf dogs are difficult to train and may develop behavioral problems as they are easily startled. Most often these dogs are discarded at animal shelters. Many breed clubs such as the Dalmatian Club of America have adopted the practice of euthanizing all their deaf puppies. Resources do exist for training deaf dogs such as materials on teaching them sign language. It is recommended deaf dogs are not bred.
Autoimmune: Autoimmune Hemolytic Anemia (AIHA)
Cocker spaniels have a predisposition for autoimmune hemolytic anemia (AIHA). In AIHA, the dog's own immune system attacks its blood cells. In some cases the cause is known such as AIHA secondary to systemic lupus erythematosus (SLE). In other cases, the cause is unknown but possibly due to bacterial infections, medications or vaccines. Cocker spaniels are particularly affected with the acute form of AIHA. Symptoms include pale complexion (i.e. the gums), fatigue, and sometimes jaundice. A swollen abdomen is also indicative due to an enlarged liver. Diagnosis is made by physical examination and blood tests. Treatment includes the use of steroids as they subdue the immune response. Blood may be transfused if too much hemoglobin is lost. If steroids do not provide adequate results, chemotherapy drugs such as cyclophosphamide or azathioprine are given as well. Most forms of AIHA are treatable but death may occur due to blood loss and related complications. Cocker spaniels with AIHA should not be bred.
Autoimmune: Autoimmune Thyroiditis
Autoimmune thyroiditis also results in hypothyroidism (see below). Studies have concluded American cocker spaniels have a high prevalence for autoimmune thyroiditis. The cockers' immune system forms antibodies that attack its own T3, T4, and thyroglobulin, a substance necessary for forming thyroid hormones. Symptoms, diagnosis, and treatment are similar to those listed below under hypothyroidism except diagnosis of autoimmune thyroiditis includes the presence of thyroid antibodies in the blood.
The cocker spaniel has a predisposition for hypothyroidism. Hypothyroidism results when its body fails to produce sufficient amounts of thyroid hormone. Thyroid hormone increases the metabolism rate and is necessary for normal regulation. Dogs are most commonly affected with secondary hypothyroidism: that is the thyroid gland becomes hindered in some way. In this case, the hindrance is most likely caused by a space-occupying tumor between the ages 4-10 years. Hypothyroidism my also occur via autoimmune destruction of the thyroid gland. Symptoms are related to a slowed metabolism including mental dullness, exercise intolerance, lethargy, weight gain (without increase food consumption), hypothermia, dry skin, and excessive shedding or hair loss. With hair loss, darkening of skin and itching may also occur. Infertility may occur. In severe cases, thickening of the skin results giving the dog's face a puffy appearance. Lethargy may progress to stupor and coma. Diagnosis is made by blood test. Treatment is provided by thyroid hormone replacement according to blood levels.
Skin Problems: Primary Keratinization Disorder or Primary Seborrhea
Primary seborrhea is commonly recognized in the cocker spaniel. Primary seborrhea is caused by overproduction of skin cells including sebaceous (oil) cells. The skin appears greasy and scaly with a foul smell. The trunk, back, and ears are most commonly affected. Itching varies among those affected. Diagnosis is done by biopsy. Treatment includes the administration of retinoids (vitamin A derivatives) such as isotretinoin. Concurrent treatment with antifungals may be indicated as primary seborrhea may be associated with yeast infection. Routine use of antiseborrheic shampoos and moisturizers is also recommended
Skin Problems: Food Allergies
Studies have shown the American cocker spaniel is at risk for developing food allergies. A food allergy is a result of the immune system responding to certain foods. The most likely symptoms of a food allergy are itching in the ears in feet. A closer inspection will reveal reddened and swollen skin in the affected areas. The affected areas may appear bumpy and feel hot. To a varying degree, the dog may experience gastrointestinal (GI) symptoms as well such as fecal mucus, fecal blood, and frequent stools; all symptoms of colitis. It may be possible for the dog to act weakly as well. The diagnosis of food allergies is done by the elimination diet. During the elimination diet the dog is fed one starch and one protein (i.e. pork and potatoes). After about 8-12 weeks of this diet, in the absence of allergy symptoms, different foods are introduced one by one to see if an allergic reaction occurs. Each new food introduced into the diet is trialed for about 1-2 weeks. If no allergy occurs another food will be added to the diet. The most common cause of food allergies in dogs are beef, chicken, milk, eggs, corn, wheat, and soy. Once the offending food is identified it can be avoided the dog's diet.
Although Sheldon Gerstenfeld, V.M.D., author of ASPCA Complete Guide to Dogs, claims American cocker spaniels are prone to urological disorders this author is unable to substantiate this claim through a review of current literature. Two studies in this subject were in fact conducted on English cocker spaniels not American. If urological problems do occur in American cocker spaniels they have not been well documented.
References
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© (2002) M. Villanueva