Are dog vests or sweaters really necessary?

Dear Paws: You recently addressed someone leaving a dog out in the cold weather. Your answer was great, except I wonder about the wisdom of putting a warm vest on the dog. It is my understanding that dogs have two layers of skin with air in between, which helps heat their body and keep them warm. When you add a coat or vest it presses down on the air pocket and causes them to be colder. Am I wrong? — Suzanne, via email

Dear Suzanne: Well — while dogs’ skin does help regulate their temperature, their fur plays a bigger role in insulating them from cold weather. You’re probably thinking of a dog’s double-layered winter coat, where air between the thick undercoat and the top fur helps keep them warm.

Some breeds of dog have much thicker undercoats, such as Huskies and Malamutes. Most of us have seen pictures or video of sled dogs, for example, who rarely wear coats while working nor at the end of the day. Their bodies generate plenty of heat while they’re active, and their undercoat insulates them from the cold when they’re not active. These dogs eat a specific diet as well, and they are bedded down in shelters that protect them from extreme cold. They are also acclimated to their outdoor environment.

However, other breeds don’t do well at all in below-freezing temperatures — some are small and short-haired, for example, or they’re in poor health, or they’re very young, or they are just not accustomed to spending long periods outside.

The most important factor in deciding what your dog needs is you. For a 20-minute walk outside, most healthy dogs don’t need a coat. However, if your dog gets cold quickly or appears to be suffering even after a short time outside, it’s worth trying a well-fitted vest or sweater.

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