Pet Vet column: Helping your pet manage winter blues
Integrative Pet Vet
The holidays — what a wonderful opportunity to share time with family and friends. Pets have become such an important part of our daily life that many consider these furry companions as part of their families. While our pets provide us with innumerable health benefits and companionship, they also provide an invaluable opportunity to study the aging process. Dogs are receiving widespread interest for human aging studies because they age rapidly compared to humans and in very similar ways. Aging is the result of multiple processes that result in decline of organ and tissue function. These changes include heart disease, liver and kidney problems, cognitive declines, nerve and muscle degeneration, and increased risk for osteoarthritis and cancer (see previous article Teaching About Old Dogs). In addition to these changes, dogs share their environment with humans which means that they are exposed to similar environmental conditions as humans.
With this information in mind, it is not surprising that pet companions are thought to also experience seasonal affective disorder (SAD) like humans. Affected humans experience feelings of sadness and loss of energy around the times of the year when the days are the shortest, typically December through February. These individuals have difficulty regulating serotonin and melatonin. They also tend to have low levels of vitamin D. Serotonin is a substance that is responsible for helping to balance mood. During summer, exposure to sunlight aids in maintaining normal serotonin activity. When sunlight decreases in winter, serotonin activity decreases. In addition, affected individuals experience increased production of melatonin. Melatonin is produced in a part of the brain (pineal gland). It is produced in response to darkness and helps to promote sleepiness. As the winter nights become longer, there is an increased production of melatonin and a corresponding increase in sleepiness and lethargy.
While dogs have similar brain chemistry to humans, it has not been clearly established that dogs and cats experience SAD. A small survey in Britain provided some answers but the study relied on owner perceptions of their pet companion without supporting scientific documentation. In this study it was determined that 40 percent of dog owners reported a decline in their dog’s mood, 50 percent thought their dogs slept longer, and 40 percent thought their dogs were less active. Interestingly, over 30 percent thought their cats seemed “sadder” and less playful. For both dogs and cats, 25 percent of owners thought their pet’s appetite increased during the winter.
One criticism of this survey is that pets are very good at mirroring the emotions of humans. The ability of dogs to recognize emotions in humans was shown in a study that evaluated the how well dogs can pair facial patterns with verbal cues. This ability to recognize emotions has only been previously shown in primates and the additional ability to recognize emotions across species has only been shown in humans. Obviously this complicates interpretation of owner observations of pet’s emotional states.
Regardless of whether companion pets experience SAD, there is an important message regarding the close relationship that humans have with companion pets. Take time to walk your dog regularly, especially in the winter. The exercise is invaluable and will provide opportunities for more exposure to sunlight during the daylight hours. Keep in mind that dogs do not produce vitamin D from sunlight. Consider testing for vitamin D levels and supplementing as needed (see previous article Understanding the Importance of Vitamin D for Pets). Play with your dog and cat indoors. Find activities that are stimulating for them and get them moving regularly. Provide appropriate toys. Increase the full spectrum light in your home during the winter. Take care of yourself because your health and emotional well-being can affect your pet companions. Enjoy the holiday season and include your companion pet whenever possible.
Ron Carsten, DVM, PhD, CVA, CCRT was one of the first veterinarians in Colorado to use the integrative approach, has lectured widely to veterinarians, and has been a pioneer in the therapeutic use of food concentrates to manage clinical problems. In addition to his Doctor of Veterinary Medicine, he holds a PhD in Cell and Molecular Biology and is a Certified Veterinary Acupuncturist and Certified Canine Rehabilitation Therapist. He practices integrative veterinary medicine in Glenwood Springs.