Dogs Favour Humans – Part 1

Scientists at Emory University in Georgia, U.S.A., have discovered that dogs prioritize the smell of a “familiar” human over just about anything else.  Using Magnetic Resonance Imaging (MRI), scientists offered five scents to 12 subject dogs:


     - Familiar human

     - Familiar dog

     - Self

     - Strange human

     - Strange dog




DOCTOR DOG?

Research has proven that a dogs’ sense of smell can be more than 10,000 times that of a human nose, depending on the breed.  If we compare human to canine olfactory capabilities, we have to look at the structure.  In both people and dogs, there are two bony plates inside the nasal cavity called turbinates which hold a spongy membrane that functions as the scent detector.  It also includes the nerves to send the information from the membrane to the brain.

  • If we were to spread out the membrane, the human version would be about the size of a stamp.The dog’s membrane, however, would be about 60 inches, or the size of a 7 ½ x 9” piece of paper.
  • The number of scent receptors in the average human is approximately 5 million; for the average dog it can range from 125 million (short snouted dogs, like a pug) to 300 million (longer snouts, bred for enhanced smell capabilities, like a beagle or bloodhound).

Is it any wonder dogs ‘see’ with their nose, and not their eyes like us olfactory-challenged humans.  The sheer volume of information they receive and process through that one sense is absolutely incredible.  Research has proven that dogs can aid in diagnosing a number medical concerns.


Did you know,

  • A study was completed by the Pine Street Foundation in California where five dogs were trained to detect breast and lung cancers in a breath sample based on the unique chemical signature of each type of cancer and achieved a 88-99% success rate?
  • There are service dogs who can detect, prior to the onset of any symptoms, a seizure and alert the individual or assist the owner during a seizure or its aftermath?The University of Florida completed a study in 1998 that determined it was the ability to smell internal body odors associated with seizures with incredible accuracy.
  • The University of Bristol and the University of Dundee in the United Kingdom, in collaboration with the charity Medical Detection Dogs undertook a study to identify if dogs could sniff out low blood sugar levels (associated with Diabetes and Hypoglycaemia).The results, based on changes in blood chemistry, indicated that “multiple findings point consistently to the potential value of  trained alert dogs." 
  • Bacteria called Clostridium difficile causes an infection that can result from long term antibiotic use, and is most often seen in hospitals and long term care facilities.The symptoms can range from mild to severe and include diarrhea, fever, nausea, abdominal tenderness and colitis (inflammation of the colon).Dogs have proven to be able to detect this infection 100% of the time by sniffing the air around an infected patient.

There are so many more stories, studies and research that have been completed or are currently underway about the incredible nose and scent detecting abilities of dogs.   The greatest value, though, is proof that our human bodies produce and expel organic material that can be detected in the air.  This supports the development of instruments and machines that can quickly, less invasively, diagnose illness. 

Whether dogs are used in the medical field to detect various medical illness, or disease and infection outbreaks, or canine study data is channeled into machinery, the contribution of our canine friends to the medical field cannot be discounted. 


A dog’s bedside manner is better, too.


Are your dog and mine related?
Michelle HIbler


Would you have guessed that your Siberian Husky is related to the Chow Chow? How about the Welsh Corgi to the Greyhound? No? And that cute little Gwenna, a miniature wire-haired Dachshund, is a distant cousin to the Bloodhound?  That's what a new family tree of dogs reveals.

Scientists from the US National Institutes of Health began studying dog genomes two decades ago. They discovered that the 161 breeds they analyzed fell into one of 23 groupings called clades.  Although they may have been bred independently in different parts of the world, most of the dogs in a clade have similar traits --  they're herding dogs, retrievers bred for hunting, or large dogs bred for strength. Others are quite different, however -- how about the Papillon and the American Eskimo Dog?


Check out these articles to view the colour wheel of clades and learn more about the study and what it can mean for human health:

www.mnn.com/family/pets/stories/where-your-dog-canine-family-tree

www.scientificamerican.com/article/dog-family-tree-reveals-hidden-history-of-canine-diversity


www.theguardian.com/science/2017/apr/25/bow-wow-scientists-create-definitive-canine-family-tree

Dog Walkers' Association

“A dog is the only thing on earth that loves you more than he loves himself.”
― Josh Billings, Author

David Bartlett Park

The Science of Dogs

“If you pick up a starving dog and make him prosperous he will not bite you. This is the principal difference between a dog and man.”
― Mark Twain, Humourist, Author

“I'll believe it if I see it" for dogs translates to "I'll believe it if I smell it." So don't bother yelling at them; it's the energy and scent they pay attention to, not your words.”
― Cesar Millan, The Dog Whisperer

They then studied three areas of the brain:  the olfactory bulb (the neural structure of the vertebrate forebrain involved in smell); the caudate nucleus (a paired structure that makes up the basal ganglia and is involved in memory and learning); and the whole brain.  The olfactory bulb scans showed no difference between the five scents; however, the scans lit up in the caudate response demonstrating the dog could not only differentiate between the five scents, it was most active with the familiar human scent.  It activated the reward-response center of the brain, even over itself or other familiar scents. 

In the whole brain scan, it showed the greater activity to the familiar scents in the medial frontal cortex.

Why the familiar human scents seem to have a special place for our dogs is not known.  Scientists can infer, or defer, but us owners know the truth – it’s a love thing.

Read the whole article at:  http://
www.sciencedirect.com/science/article/pii/S0376635714000473