Dear Dr. Fox: From time to time, we see two shorn English sheepdogs locally.

I assume they are shorn because the owner believes them to be cooler in the summer if they have less hair. I seem to remember hearing or reading somewhere that canine hair follicles were hollow, and therefore, the fur acted as insulation against the heat.

Am I misinformed? I asked my son’s wife, who is a veterinary tech, and she didn’t have a clue, so I thought that I would ask the master. — D.L., Washington, D.C.

Dear D.L.: The coat of these dogs, coupled with high humidity, probably resulted in the dogs suffering some heat stress and distress this summer.

Dogs of different breeds and with different coats may need close attention in summertime, since coats that get moist can lead to fungal/yeast infections and other skin problems, along with a nasty odor.

Hollow hair is an adaptation of animals that live in very cold climates. Reindeer, caribou, llamas and alpaca have soft hollow hairs, densely packed together to help retain body heat. Polar bears have hollow hair: Each hair is a clear, hollow tube that reflects the light, making polar bears’ fur appear white, though each hair is actually transparent.

In dogs, wolves, Arctic foxes and other mammals, air is trapped between the under-fur and the longer upper guard hairs, serving as a layer of insulation against cold and heat.

I am not aware that dogs have any hollow hairs. Muscles in the dog’s skin can fluff up the coat, creating even more insulation. Most hair follicles have an associated oil gland that works to keep the skin pliable and the hair smooth. Dog breeds that were developed to retrieve game from water have very active oil glands, a factor that helps to waterproof their fur and skin.

Dear Readers: The Indiana State Board of Animal Health reports that 10 horses have either died or had to be euthanized because of the impacts of eastern equine encephalitis (EEE) on their nervous systems.

EEE is one of several New World encephalitis viruses. It is also what is known as an arbovirus: a virus that is spread by a mosquito or other arthropod. (West Nile is another.) To combat it, veterinarians prescribe vaccinations for susceptible horses, donkeys and mules. EEE can be spread to humans, and is one of the most dangerous mosquito-borne diseases in the United States. It is fatal to approximately 30 percent of people who contract it; survivors are likely to have severe chronic neurological problems.

According to the Centers for Disease Control and Prevention, around seven human cases of EEE are reported in the U.S. each year, mainly in the eastern or Gulf Coast states. Positive tests in northern Indiana came in the wake of at least seven human deaths from the disease so far this year. There are reports that at least 27 people have tested positive for the disease in six states.

The EEE virus has killed two Mexican gray wolf pups at Binder Park Zoo in Battle Creek, Michigan, which means that dogs could also become infected.

In my opinion, the climate crisis is a major factor creating more favorable habitat (longer, warmer and wetter summers) for mosquito proliferation, along with the biodiversity extinction crisis, where widespread use of pesticides have killed off natural predators of aquatic mosquito larvae and flying, breeding adults.

The best personal and companion animal protection is to apply a spritz of oil of lemon eucalyptus (OLE). Use citronella candles outdoors, check screens on your windows, porches and patios; and avoid going out unprotected in the early evening. Note: I would not use OLE on self-grooming cats. Keep them indoors!

For more details, go to consumerreports.org and search “insect repellent.”

Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox’s website at DrFoxOneHealth.com.