Like in humans, hormonal disorders plague dogs too, and demand attention, treatment, and care. Hormones are chemical messengers that trigger and regulate physiological reactions inside the body and contribute towards maintaining an ideal condition in the body (homeostasis) which, in turn, ensures balanced metabolism, highly desired for a good health. Here is a brief attempt to understand hormonal disorders in dogs, their causes, remedy, and care.
The question itself has the answer. It’s either too much or inadequate secretion of hormones. Accordingly, the over-secretion situation is prefixed as Hyper (hyperthyroidism) while the opposite one is prefixed as Hypo (hypothyroidism).
Hormones are secreted by glands in the dog’s body as shown in the picture above and are released into the bloodstream for distribution across desired organs. There could be different factors affecting the functioning of the glands like autophagy, tissue degeneration, lack of nutrition, development of nodules or tumors, and so on.
Both the conditions lead to disruption in the functioning of some or the other organ or organ system in the body of a dog, which is sometimes recognizable immediately and sometimes at a later or delayed stage. Likewise, the consequences could be simple or complex and so could be the treatment.
|Endocrine Gland||Hormone(s) Produced||Function|
|Pituitary gland (anterior lobe)|
|Corticotropin(adrenocorticotropic hormone)||Stimulates the production and secretion of hormones by the adrenal cortex|
|Growth hormone||Promotes growth of the body and influences the metabolism of proteins, carbohydrates, and lipids|
|Follicle-stimulating hormone||Stimulates the growth of follicles in the ovaries and induces the formation of sperm in the testes|
|Luteinizing hormone||Stimulates ovulation and the development of the corpus luteum in the female and the production of testosterone by the testes in the male|
|Prolactin||Stimulates the mammary glands to secrete milk|
|Thyroid-stimulating hormone||Stimulates the production and secretion of thyroid hormones by the thyroid gland|
|Pituitary gland (posterior lobe)|
|Antidiuretic hormone; also known as arginine vasopressin||Causes the kidneys to conserve water by concentrating the urine and reducing urine volume; also has lesser role in regulating blood pressure|
|Oxytocin||Stimulates the contraction of smooth muscle of the uterus during labor and facilitates ejection of milk from the breast during nursing|
|Parathyroid glands||Parathyroid hormone||Raises the blood calcium concentration by promoting absorption of calcium by the intestine, mobilizing calcium salts from bones, and increasing the ability of the kidney to recover calcium from urine; also lowers phosphate by enhancing its excretion by the kidneys|
|Thyroid hormones (T3 and T4 )||Increase the basal metabolic rate; also regulate protein, fat, and carbohydrate metabolism|
|Calcitonin||Participates in calcium and phosphorus metabolism; tends to have the opposite effects of parathyroid hormone|
|Aldosterone||Helps regulate salt and water balance by retaining sodium (salt) and water and excreting potassium|
|Cortisol||Has widespread effects throughout the body; involved in the response to stress; active in carbohydrate and protein metabolism; helps maintain blood sugar level, blood pressure, and muscle strength|
|Epinephrine (adrenaline) and norepinephrine||Released in response to stress; stimulates heart action and increases blood pressure, metabolic rate, and blood glucose concentration; also raises blood sugar and fatty acid levels|
|Insulin||Lowers blood sugar level; affects the metabolism of sugar, protein, and fat|
|Glucagon||Raises blood sugar level, thus opposing the action of insulin|
|Estrogen||Controls female reproductive system, along with other hormones; responsible for promoting estrus and the development and maintenance of female secondary sex characteristics|
|Progesterone||Prepares the uterus for implantation of the fertilized egg, maintains pregnancy, and promotes development of the mammary glands|
|Testosterone||Responsible for the development of the male reproductive system and secondary male sexual characteristics|
Common Hormonal Disorders in a Dog
Scientifically the infections are called alopecia (early stage hair loss) and dermatosis (Later stage hair loss).
Causes: The diseases are caused by an imbalance in the reproductive hormones called estrogen (female) and androgen (male). The hormones are produced in male and female dogs by adrenal gland.
Diagnosis and Treatment
One should reach out to a veterinarian for diagnosis and explain to him or her about the thorough history of the dog’s health, including symptoms and consequences. The pet owner must mention any possible incidents that might have triggered the skin infection.
The diagnosis starts with a thorough physical examination of your dog. If required, the vet may recommend a biochemical profile, including a complete blood count, a urinalysis, or skin biopsy. At times, X-ray, ultrasonography, laparoscopy or imagining is required too if there is some internal complications emerge in the skin.
Medications for treatment are suggested based on the diagnostic report. In some cases, the vet may prescribe compounding medicines based on the condition of the pet. Surgery and radiotherapy are also suggested in extreme condition.
Cushing disease is categorized into two categories: 1. hyperadrenocorticism resulting from excessive secretion of cortisol by adrenal glands; 2. Panhypopituitarism caused due to low secretion of anterior pituitary hormones by pituitary gland also sometimes called as the master endocrine gland.
The disease is common in dogs but not in other species. Dog breeds like Miniature Poodles, Dachshunds, Boxers, Boston Terriers, and Beagles are at increased risk. Middle-aged and older dogs are more prone to the disease.
Causes: In most affected dogs (85 to 90%), the cause is a small, benign pituitary tumor. In the remaining 10 to 15% of dogs, the cause is a tumor of the adrenal gland itself. The tissue of the
Diagnosis and Treatment
A series of laboratory tests might be required to conclude the causes due to a high percentage of false-positives in the test results. A gap of 3 to 6 months is required, at times, between two subsequent tests. Additional tests are conducted to know whether the disease is caused by a tumor of the pituitary gland or the adrenal gland.
The influence of the drug should be monitored regularly as a reduced level of cortisol can result in reduced appetite, vomiting, and diarrhea.
The thyroid gland is a 2-lobed gland in the neck that secrets 2 iodine-containing hormones (thyroxine), viz., T3 (triiodothyronine) and T4 (tetraiodothyronine), which are essential for running the vital metabolic activities in a smooth manner. The hormones are required in the right condition. Hypothyroidism is a situation where the gland fails to produce an adequate amount of the hormone which, in turn, reduces the metabolic rate. This hormonal disorder is common in dogs aging 4 to 10 years. The reverse condition is known as hyperthyroidism.
Symptoms of Hypothyroidism
Symptoms of Hyperthyroidism
Hyperthyroidism is much more common in cats than in dogs.
The inflammation or shrinkage of the tissues of thyroid gland is responsible for hypothyroidism. In rare cases, cancer or congenital defects can trigger the health issue in a pet. Tumor or thyroid cancer in some cases is related to over secretion of throxine hormone. A prolonged medication to check hypothyroidism or intake of antibiotics for dogs can also cause hyperthyroidism.
Diagnosis and Treatment
Observing the symptoms and correlating them with clinical findings based on tests of blood and stool samples, a veterinarian recommends a medication or a mixture of medications along with the right dog nutrition to help the dog successfully recover from the thyroid related issues. Sometimes, vets recommend thyroid medication for dogs based on a specific condition of the pet. If you notice your pet suffering from any of the symptoms over a period, must go for a thyroid test with a recommendation from your vet.