Keeping aging dogs healthy in twilight years
By Allison Tonini
research corrects metabolic issues
Dogs, like people, begin to experience health problems as they age. Diagnosing these geriatric illnesses can be challenging. All too often, metabolic and endocrine system disorders are the silent factors leading to a senior dog’s sudden decline in health.
Although it is normal for aging dogs to experience fluctuations in their production of hormones and enzymes, extremely high or low levels of a hormone affect glandular function and can progress into full-blown metabolic or endocrine system disorders.
About 85 to 90 percent of Cushing’s cases are caused by an abnormality, such as a benign tumor, in the pituitary gland. The pituitary gland produces corticotropin, which controls the secretion of hormones in the adrenal glands. When the pituitary gland produces too much corticotropin, the adrenal glands follow suit and overproduce corticosteroids.
Owners often mistake the signs of Cushing’s for early senility. If left untreated, Cushing’s disease can lead to more serious consequences, including diabetes, enlarged liver, pancreatitis, weakening of the heart, high cholesterol, hypothyroidism, skin infections and nervous system problems. Although all dogs are susceptible, the disease is usually seen in certain breeds, including Poodles, Dachshunds, Boston Terriers, Beagles, Schnauzers and Boxers.
Morris Animal Foundation is currently funding two studies on Cushing’s disease. In one study, lead researcher Dr. Ellen N. Behrend, of Auburn University, is working to find out if a new diagnostic test that measures the sex hormone concentration in a dog’s blood is an accurate indicator of Cushing’s disease. Dr. Behrend’s hypothesis is that increased sex hormone levels can’t always accurately predict disease and that, as a result, Cushing’s disease is significantly overdiagnosed. She and her team hope to improve the diagnostic accuracy of Cushing’s disease through their research.
In a Pfizer Animal Health–Morris Animal Foundation Fellowship, Dr. Miriam J. Kool, of the University of Utrecht in the Netherlands, is studying adrenocortical tumors in hopes of finding a better understanding of how Cushing’s disease develops. Knowing how the disease begins and matures will ultimately help researchers develop new treatment methods for dogs with adrenal tumors.
a deficiency that causes disease
On the flip side of Cushing’s is Addison’s disease, the common name for adrenocortical insufficiency. Whereas Cushing’s disease is characterized by the production of too much corticosteroid, with Addison’s disease the body produces too little. Though the disease is relatively uncommon in dogs, certain breeds, including Nova Scotia Duck Tolling Retrievers, Bearded Collies, Great Danes, Leonbergers, Portuguese Water Dogs, Standard Poodles and West Highland White Terriers, have a much higher risk.
Recently, Dr. Angela M. Hughes and her team from the University of California–Davis identified a region of the genome that is associated with the development of Addison’s disease in Nova Scotia Duck Tolling Retrievers. Although additional genes are likely involved, Dr. Hughes’s study is the first step toward one day developing a genetic test that will eliminate Addison’s disease through more informed breeding practices.
Aging dogs can also develop serious illnesses, and some critically ill patients appear to have low levels of ACTH and cortisol hormone. A lack of these hormones, which help the body fight the illness, can lead to higher death rates. With Foundation funding, Auburn University’s Dr. Linda Martin is working on a test that would help veterinarians detect low hormone levels in critically ill dogs so that they could be treated more effectively.
preventive care can lead to early diagnosis
One of the most important things that a dog owner can do is practice preventive health care. Most metabolic and endocrine system disorders are manageable, so the earlier the symptoms are noticed, the easier the disease is to treat. Because of old age and increased vulnerability to disease, senior dogs need one or more routine veterinary exams per year. As a dog ages, a veterinarian visit will likely consist of a few additional tests and a more thorough checkup, compared with the visits from the dog’s younger years. Another preventive health care step for owners of senior dogs is to carefully monitor the dog’s everyday behavior for changes, which can signify a health problem.
Vigilant owner care and research into new treatments can keep aging dogs comfortable and happy during their twilight years.
Posted by MAFon November 28, 2011. Permalink