- Global Canine Communication


Canine Reproduction Section


The connection between sunlight, cancer, fertility, and vitamin D will truly "enlighten" you! Why genetic diseases and health problems plague both dogs and people.





by Barbara J. Andrews, AKC Hall Of Fame Master Breeder


Canine cancer rates are spiraling out of control.  Bone and joint deformities plague breeders.  Every time you turn around there's a new genetic disease. 


PUPPIES IN HEALTHY SUNLIGHTWe may complain about puppy mills but bitches in those outdoor cages and pens breed easily, conceive regularly, and whelp big litters.  We can not say the same about pampered purebreds and you are about to learn why.


Stick with me. I promise this will change the way you think about your dog's health - and your own!  If you haven't read Part 1 - Into The Sunlight, you might want to do that first because it gives you solid background on the connection between natural sunlight, thyroid hormone and other glandular functions that affect canine reproduction... or stick with me and click that link later.  Here's the thing... All mammals require at least 10 hours of sunlight.  Avoidance of sunlight to prevent cancer is a medical misconception which, like low-fat diets that encourage people to eat chemical-laden fake food, has seriously bad effects on reproduction, growth, and the immune system.


We adversely affect our dog's health and reproductive ability by keeping them indoors, in fact, "house dogs" - our closest friends, are the most affected by sunlight deprivation.  Lack of sunlight prevents absorption of vitamin D but it doesn't stop there.


It is hard it is to get medical truth to public.  Michael F. Holick, MD, PhD, professor of medicine and physiology at Boston University School of Medicine, and until 2000, chief of endocrinology, metabolism and nutrition was asked to resign because he advocated moderate exposure to sunlight, not total avoidance.


Avoid the sun?  Dermatologists are well paid to warn us about sunlight and ultraviolet light, scaring us to death with fears of melanoma, which of course, creates a huge demand for sunscreen - and cancer screenings. Ka-ching $$$


Canine cancer is on the rise - and dogs don't smoke... Even as we are warned about sunlight and skin cancer, the American Cancer Society admits "We do not yet know exactly what causes melanoma…”  If you read, you are aware of the link between “manufactured” food (laced with chemicals and preservatives) and serious health problems, including cancer. What we now know is that vitamin D may also help prevent a variety of cancers!


Could that explain the higher cancer rate among pampered pets and show dogs? Certainly they spend more time indoors than the street mutt or hunting dog.  Shouldn't we be reaching out to sunshine?  The one thing that is life-sustaining, energy-giving, mood-lifting, and health preserving?  Surely that is why the Creator put us third from the center of our universe... the sun. (Pluto is last and contains no signs of life.)  We are perfectly positioned to receive exactly the right amount of sunlight to sustain human life.  We must reach out to that energy, not hide from it!


The National Institute of Health has stated "laboratory, animal, and epidemiologic evidence suggest that vitamin D may be protective against some cancers” and subsequent dietary surveys associated "a higher calcium and vitamin D intake with a lower incidence of colon cancer." Vitamin D from natural sunlight may also help protect against prostate cancer which is increasingly common in dogs.


Professor Holick, M.D. has over 200 PubMed articles on the topic of vitamin D, relating it to the prevention of cancers, type 1 diabetes, heart disease, and osteoporosis. Even so, sunlight's beneficial biological effect seems to have been lost to modern medicine.


I have written about sunlight deprivation many times and okay, most of you were bored to death but a few actually said that you don’t wear sunglasses as much, or you quit drawing the drapes on your house dogs during the day, or you’re using those natural spectrum light bulbs during the long winter months. Best of all, several readers have said bitches they were about to place in pet homes, suddenly began to produce puppies!


Here’s a personal example I hope will stick in your mind. In the late 80s I flew to California to spend a few days with Jean Mills, developer of the hybrid Asian Leopard/domestic cat which finally became TICA registered as the Bengal - I know, that makes no sense... When the f2 female I had bought from her would not “call” for a mate, Jean said to put a halogen light down low so it would shine into the cat’s eyes as she moved about the enclosure. Huh? She explained that the light would stimulate her breeding hormones.


I started to reply that I had built an elaborate outside cattery but Jean said the sunlight was different in NC than in Southern California and the move had thrown her off cycle. Oooo-kay…… I did as she said.  Within two weeks the cat began calling (came into estrus) and I added sunlight exposure to my health notes! She produced a lovely litter (kitten shown at right).  The point is -make sure your breeding and show dogs are getting at least 8 hours of direct sunlight!


About a year later at the International TICA show in CA, a Bengal breeder remarked that cats can not be kept under artificial light, that they “go crazy” and will not ovulate. I nodded knowingly but then she said that fluorescent lights were the absolute worst!  Whatever... When I returned home, I glanced at the brand new lights over my work center and thought about how grumpy I had become... I reflected on the many hours I had previously spent outside; training, bathing and grooming my dogs and how since starting the Akita book, I had been glued to a computer screen.


The very next day I had those lights removed, ordered an Ott Light for my desktop, picked up a leash and headed for the sunshine!


Try it. Open those curtains, sunlight is no harder on the furniture than a bunch of dogs. Run the kennel dogs off those comfy beds and out of the air conditioning. If you’re in the blazing south, arrange your schedule so the dogs get outside in the early morning and late afternoon. Put puppies outside, let them get dirty, dig holes, and eat grubs but above all, let them soak up the sunshine.


Meet the Editor and Author Barbara J. "BJ" AndrewsStraight legs. Strong bone. Healthy immune systems and reduced cancer risk. Normal ovulation and easy breeders. Those are your tangible rewards. Do it for yourself, especially if you work nights and sleep days. We could give you statistics on night workers but I don’t want to scare you.  Besides, TheDogPlace is for dogs.... and smart owners who care enough to care!


And if you missed part 1... >  Sunlight and Fertility

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Fat and Fertility

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