Admin, Author at Daily Dog Discoveries

I am Your Dog’s Blood Brain Barrier

June 27, 2016January 25, 2016 by Admin

Today is Monday’s Marvels and what’s more marvelous than a special barrier that protects the dog’s brain from potentially harmful substances? Owners of a sub-population of collies and several other herding breeds, in particular may be well aware of the risks their dogs may be susceptible to due to the way their blood brain barrier is structured, but this is something that certainly may interest owners of any other types of dogs as well. As we marvel at this structure, we can gain more insights on how the blood brain barrier works and gain more information about possible problems. So let’s see what our dog’s blood brain barrier has to say so we can get more acquainted with this structure. So let’s welcome today the dog’s blood brain barrier!

Let Me Introduce Myself!

Hello, you may not know me well, but you sure need to thank me for protecting something as important as your dog’s brain! I might not be popular as the brain, but I sure need a place of honor for ensuring your dog’s brain is shielded from potential dangers. I take no offense if you have never heard about me before, but my job today is just this, introducing myself and letting others become aware of my noble duties. While time ago, it was suggested that I was present only in an immature form in young animals, today studies have instead indicated that my sophisticated structure is actually already somewhat operative at birth! I am just quite permeable in neonate puppies according to veterinarian Kit Kampschmidt. This means that neonates are more vulnerable to the toxic effects of certain drugs, which is why most vets are cautious in medicated those youngsters unless strictly necessary!

Warning, Restricted Area

What’s my day like as a blood brain barrier? My main role is allowing the entry of essential nutrients such as glucose and several amino acids while blocking certain substances from reaching the brain. To be more precise, I have a network of blood vessels lined with tightly wedged endothelial cells that form a nearly impermeable boundary responsible for restricting the passage of certain substances from the bloodstream to your dog’s brain. Hey, if you rarely hear about brain infections, it is thanks to me! Indeed, I effectively protect the brain from harmful substances such as toxins and bacteria. At the same though, as mentioned, I must grant access to important sugar and amino acids. These latter successfully gain access courtesy of special transport systems that move them across the barrier and into brain tissue as needed.

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When Things go Wrong

As effective as I am in restricting access to the brain, I must admit, I am not invincible. Sometimes cancers or bacteria break me down which allows small compounds that normally wouldn’t come through to gain access. When this happens, this can be bad news. Since my barrier is effective at preventing the passage of foreign substances, I may prevent certain life-saving drugs from reaching the brain. Antibodies meant to the fight the bacteria are also too large to make it through my barrier, so really only a few selected antibiotics are able to pass. Administering them directly into the cerebrospinal fluid may seem like a good option, but it’s quite a tortuous trip to reach all those tight interstitial passages to the brain. One good thing though is that when I am inflamed, I become more permeable, which increases absorption of certain antibiotics, but you must be careful too as this also means that the brain becomes more vulnerable to the infiltration of bacteria and viruses.

The Issue with Collies

Owners of collies/collie mixes and other herding dogs are likely aware of the problems associated with giving these dogs the heartworm drug ivermectin. The issue with ivermectin toxicity observed in collies was first noticed in the 1980s. What’s the problem in these dogs? You see, ivermectin is toxic to pesky parasites, but it is thanks to me that most breeds aren’t affected. As a barrier, I prevent this drug from reaching your dog’s brain, but since parasites do not have a blood brain barrier, this drug affects them without poisoning your dog. You must therefore thank me for allowing this form of “selective toxicity.”

However, it was discovered that a sub-population of collies (along with several other herding breeds, see quote below) had a tendency to accumulate high concentrations of ivermectin in brain tissue which caused them severe neurological symptoms. Why? Turns out, such dogs lack a functional blood-brain barrier, explains Katrina L. Mealey a board certified veterinarian specializing in internal medicine and clinical pharmacology. The issue is the result of an altered multi-drug-resistance gene (MDR-1) which makes their blood brain barrier more permeable. It’s estimated that about 3 out of every 4 collies in the United States have the mutant MDR 1 gene, explains Dr. Joey, a board-certified veterinarian.

Affected breeds include Australian Shepherds, Collies, McNabs, Longhaired Whippets, Silken Windhounds, English Shepherds, German Shepherd Dogs, Old English Sheepdogs and Shetland Sheepdogs. ~Dr. Marty Becker

Ivermectin at high doses isn’t the only drug these dogs are sensitive to, according to Washington State University, other problem drugs include loperamide (Imodium), acepromazine and several chemotherapy and antiparasitic agents agents. Fortunately, today there are tests that can screen for multidrug sensitivity. One of them is offered by Washington State University. The old adage of “white feet, don’t treat” which refers to not treating scotch collies due to the risks associated with their “leaky blood brain barrier”, has now transformed into “white feet, test to see if you can treat” says Patricia Dowling in an article published on Can–Vet Brand Animal Health Products. So if you own a collie or other affected breed and are wondering about risks associated with giving certain medications, consult with your vet and ask about getting your dog tested.

Drugs to watch for: The tranquilizer acepromazine; the pain medication butorphanol; the anti-cancer drug doxorubicin, vinblastine and vincristine; the antibiotics erythromycin and rifampin; the anti-parasitic drugs ivermectin (in high doses), milbemycin, moxidectin and selamectin; and the anti-diarrhea drug loperamide (Imodium).~Dr. Marty Becker

I hope this article may have helped you understand me better! You know, not many people are aware of me and I thought I deserved to at least be acknowledged. The best part is that I am not exclusive to dogs, so today you have also learned something about yourself as well! Thank you for listening and enjoy the rest of your day!

Yours truly,

The Blood Brain Barrier

Did you know? According to the University of Washington website, the blood brain barrier was discovered more than 100 years ago when a blue dye was injected into the blood stream of an animal. Curiously, all the structures of the animal’s body turned blue except for the brain and spinal cord.

Disclaimer: The article is not intended to be a substitute for professional veterinarian advice, diagnosis, or treatment. If your dog is sick, please see your vet.

References:

Clinical Anatomy & Physiology for Veterinary Technicians, Thomas Colville DVM, Joanna M. Bassert VMD, Mosby Inc. St Louis, MO, 2002
Newborn rabbit blood-brain barrier is selectively permeable and differs substantially from the adult, Braun LD, Cornford EM, Oldendorf WH, J Neurochem. 1980 Jan;34(1):147-52.
Pharmacogenetics: It’s not just about ivermectin in collies, Patricia Dowling, Can Vet J. 2006 Dec; 47(12): 1165–1168.
Brain Facts.org, Society for Neuroscience, The Blood-Brain Barrier
Vet Street: Multidrug Sensitivity: What You Need to Know

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How Rock Salt Affects Dog Paws

March 15, 2022January 24, 2016 by Admin

Did you know that rock salt and ice melts can cause dry, cracked paws in dogs? It’s January, and with winter in full swing, many towns and cities are now coated with a blanket of snow. For many dogs this means romping around in winter wonderland, surely a fun activity, until those poor paws start developing unsightly and painful cracks. Why is that? Today we went on a journey to discover the effect ice melt has on dog paws and how it plays a role in causing dry, cracked paws along with other adverse effects in dogs.

The Use of Rock Salt

Rock salt is a type of salt, to be more precise, it’s sodium chloride. Also known as halite, rock salt is often employed for the purpose of melting ice. Fresh water normally freezes at 32 degrees, but if you put rock salt on ice, it lowers its freezing point, causing the ice to melt. This is why according to New England Acquarium, the ocean, which is made of salted water, is unlikely to freeze other than in very cold places, whereas ponds and lakes freeze more readily.

The process of lowering the freezing point by adding a solute (salt) to a solvent (ice) is known as freezing point depression. While rock salt is effective in melting ice, it might not work too well when it’s very cold. In some cases, magnesium chloride pellets and calcium chloride pellets are further added to rock salt or brine to make the salt more effective in melting ice at lower temperatures. Often, these products are generically called “ice melts.”

Major Corrosive Effects

“It’s estimated that more than 22 million tons of salt are scattered on the roads of the U.S. annually—that’s about 137 pounds of salt for every American” claims Joseph Stromberg, a science reporter in an article for Smithsonian.com. After the salt though does its job of melting the ice, it doesn’t just disappear from the face of earth, and this can be a big problem. While salt is ultimately a natural ingredient, what’s not natural is its concentration, remarks Richard Hanneman, President of the Salt Institute, based in Alexandria, Va. Salt is corrosive, it can easily cause vehicle parts to rust, and the metal in steel bridges, bridge decks, parking garages, lampposts and statues in proximity to roads and highways are also at risk, according to Corrosion Doctors. Not to mention, its deleterious effects to certain types of aquatic life.

Back to Rover’s Paws

If rock salt is so corrosive as to damage metal parts, it’s not difficult to imagine the effect it can have on a dog’s paws. Repeated exposure with rock salt will dry the dog’s skin and cause local irritation and cracked paws, according to Blue Pearl Specialty and Emergency Pet Hospital. To protect your dog’s paws from drying and cracking due to exposure to ice melts, the ASPCA suggests some winter tips:

Avoid walking your dog over salted areas.
Carefully inspect the paws after walking the dog.
Wash paws with warm water after outdoor play and walks.
After washing, apply a layer of Vaseline to soothe irritated feet.
Vaseline can be applied as well on dog paws prior to walking and playing as a protective measure, suggests veterinarian Dr. Andrew Jones.
Trim the hair growing between the dog’s toes (you may want to ask a groomer to do this as it requires your dog to stay very still).
Look for safer de-icing products.
Invest in some dog boots.
Don’t let your dog lick his paws and discourage the ingestion of snow or ice treated with ice melt. Also, prevent lapping up water from puddles of melted snow. Rock salt can be harmful when ingested (as explained below)!

More Than Just Paw Damage!

Prevent the snow ball effect! — Avoid the snow ball effect!

Think that rock salt may only damage your dog’s paws? Think again. The effects of rock salt and ice melts on dogs can be far more worrisome than thought. Many dogs tend to lick their paws after playing in the snow. Some dogs like to clean their feet this way or they may lick them as a response to feeling their paws irritated. Many dogs like the taste of salt, so they’ll lick them even more. Many dogs indirectly ingest rock salt from eating snow or licking puddles of melted snow. The ingestion of rock salt though can cause considerable harm.

Mild ingestion of sodium chloride may cause a dog some vomiting and diarrhea, but larger doses may trigger central nervous system signs, dehydration, increased heart rate, increased breathing , increased body temperature and even death, explains Caley Chambers, a Veterinary Candidate with the University of Minnesota College of Veterinary Medicine and extern at Pet Poison Helpline. Potassium chloride can cause gastrointestinal irritation even with hemorrhagic vomiting or diarrhea, magnesium chloride can cause gastrointestinal upset, while calcium salts can cause severe gastrointestinal symptoms. Even urea based ice melts, which are often considered the safest around pets, aren’t harmless. These can lead to salivation and mild gastrointestinal irritation, but ingestion of large amounts can cause weakness, tremors, and higher than normal level of methemoglobin in the blood.

Disclaimer: this article is not meant to be used as a substitute for professional veterinary advice. If you suspect your dog ingested ice melts, contact your veterinarian immediately or you can reach the Pet Poison Helpline at 855-764-7661 (a $49 per incident fee applies).

When Puppies Develop Their Sense of Smell

June 27, 2016January 23, 2016 by Admin

When do puppies develop their sense of smell? Today is Surprising Saturday, and we thought it was quite surprising learning that puppies are capable of using their sense of smell even before they are born! What’s even more interesting though is that there seems to be an evolutionary advantage as to why a pup’s sense of smell is present so soon. And this isn’t exclusive to puppies, it’s something that apparently occurs in human infants too. Read on to learn more.

The Aniseed Study

In a study conducted by Peter G. Hepper and Deborah L. Wells and published on Oxford Journal, 16 pregnant dogs were divided into four groups composed by four dogs. The first four pregnant dogs were fed a diet flavored with aniseed, a spice known for its aromatic scent and for being safe to use in dogs. The pregnant dogs were fed this diet during the last 20 days of gestation. The second group of four dogs were fed the aniseed flavored food the day after giving birth for the duration of 20 days. The puppies were expected to be indirectly exposed to the aniseed scent/flavor when suckling for the first 3-4 weeks. The third group of pregnant dogs were fed the aniseed flavored food both before the birth of their puppies and afterward. Finally, the fourth group of pregnant dogs were fed a normal diet with no aniseed flavor added.

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The Intriguing Results

During the study, the puppies stayed in their owner’s home and none of them were exposed to aniseed other than indirectly from the mother’s diet. All puppies were weaned from milk to solid food at around 4 to 5 weeks of age, and at 10 weeks, when the puppies were tested, all of them were eating solid food. In the test, the puppies were tested by offering them a choice between some minced chicken with a drop of aniseed and some minced chicken with distilled water. These foods were offered over the course of several days. The strongest preference for the aniseed flavored chicken was observed in the puppies who were exposed to aniseed both prenatally (in the womb through amniotic fluids) and postnatally (from the mother’s milk). Little interest for the aniseed flavored chicken was shown in both the puppies exposed to aniseed exclusively when in the womb or exclusively when nursing.

Practicing Breathing Muscles

Further proof of puppies using their sense of smell when still in the womb comes from taking a peek at them via ultrasound. Through an ultrasound, scientists were capable of gaining an “inner view” of what goes on in the womb two weeks prior to the puppies being born. The scientists found that the puppies were “exercising” their breathing muscles during this time. It’s likely that this “breathing time” provides puppies the opportunity to learn more about their mother’s distinct odor and the odor of the food she has been eating, suggests animal behaviorist John Bradshaw in the book “Dog Sense: How the New Science of Dog Behavior Can Make You A Better Friend.”

An Evolutionary Role

Why would puppies rely on their sense of smell when they are still in the womb? Interestingly, there may be an evolutionary advantage. This form of chemosensory prenatal learning may aid the puppy in learning what foods are safe to eat when weaning time is around the corner. With smells passing through the amniotic fluid, and then flavors passing in the milk, puppies may rely on their mother’s knowledge to learn about which foods are safe to eat and this can influence the puppy’s future dietary preferences. These two types of prenatal and postnatal exposure, provide the puppies with a longer period of experience on what’s safe to eat, important factors that aid in promoting their survival, further explain Peter G. Hepper and Deborah L. Wells in the study.

References:

Perinatal Olfactory Learning in the Domestic Dog, Peter G. Hepper, Deborah L. Wells, Oxford Journal, Chem. Senses (March 2006) 31(3): 207-212.

Mennella, J.A., Johnson, A. and Beauchamp, G.K. (1995) Garlic ingestion by pregnant women alters the odor of amniotic fluid. Chem. Senses, 20, 207–209.

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Dogs With a History of Working as a Team

July 14, 2016January 22, 2016 by Admin

It’s fascinating Friday, and today we’ll be tackling the fascinating history of dogs cooperating with each other. Cooperation, which is the process of working together to the same end, may have offered advantages to humans and dogs back in time when dogs were employed to carry out specific tasks, but do dogs really understand the concept of cooperation? We looked at some studies and found some interesting findings and conducted some research on dogs with a history of “cooperating” with each other.

Do Dogs Really Cooperate Among Each Other?

Well, the answer to this is that it depends. For instance, according to Brian Hare professor of evolutionary anthropology with Duke University, among wolves, cooperation is often seen when the mating pair works together in raising wolf pups. It’s also not unusual to see yearlings, young wolves that are one year old but haven’t reached their second year, stick around their parents to help out too. In domesticated dogs, things instead are quite different. When female dogs give birth, they don’t like having other dogs near their litter and the cooperation as seen in wolves is non-existent. Dogs are therefore not cooperative breeders.

However, this doesn’t mean dogs aren’t cooperative. According to a recent study from the Messerli Research Institute at the University of Veterinary Medicine of Vienna, dogs have shown pro-social behaviors towards other dogs as long as they knew the other dog. In this study, dogs were offered the possibility to pull an empty tray that would bring a treat to the other dog. It was found that dogs were more likely to pull the tray with the treat for the other dog if the other dog was familiar. It is possible that this tendency to favor familiar dogs may stem from the dog’s ancestry. Back to wolf society, considering the cooperative pup raising, cooperative hunting and territorial defense, it could be possible that dogs may have retained some of these cooperative traits reserved towards familiar dogs from their early ancestors.

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Dogs with a History of Cooperating

OK, these dogs may not be consciously cooperating in the exact same way as we humans do, but we found it interesting to learn more about how throughout history dogs have worked together whether the cooperation was intently or not. Some of these dog may have learned to cooperate this way through experience or instinct, while others may have been paired by humans so their work could offer an advantage. Regardless, it’s quite interesting how these dogs collaborated together (and some continue to collaborate) to get the task done. These are just a few examples of the many dogs with a history of having cooperated as a team to attain a final goal.

Sheriff & Deputy Sheriff

Tibetan Mastiff and Lhasa Apso: these two breeds may seem to make an odd team, but match them up and you can see how they paired well as wine and cheese. The Tibetan mastiff, a large ancient breed, has a history of guarding families, livestock and property in the Himalayan foothills for many centuries. Courtesy of this breed’s sheer size and guardian nature, it wasn’t unusual to see him pull guard duty in many mansions and monasteries. He was usually unleashed as night when properties were most vulnerable.

Along with these large dogs, you would often also stumble on the smaller lhasa apso. As a good “sheriff’s deputy” these fellows would work along with the mastiffs helping them out in their guard duties. Blessed with keen hearing and sharp barks, their main job was to act as alert dogs, barking for the purpose of informing the mastiff about anything out of the ordinary. Upon hearing the alarm barks, the mastiff would rush to investigate, and if need be, dispatch the intruders.

Shift Work for Sheep

Another impressive type of cooperation is seen in the great Pyrenees. These ancient dogs have a history as livestock guardians making them the protectors par excellence when it came to defending sheep and goats from predators. When they work together, these dogs take their guardian roles very seriously. “It’s a wonderful sight to watch our Great Pyrenees livestock dogs with the sheep and goat herds, doing what God made them to do. They’re outstanding guardians, working well in teams of two to three, each “taking their shift” around the clock through the day and night,” explains Bountiful Blessings Farm., a family run farm and breeder of great Pyrenees dogs. The Carolina Great Pyrenees Rescue warns that even though Pyrs work well as a team, it’s best to get one pup first and get it acquainted with livestock, and then, later on add another so that it can be coached by the more experienced one.

Sled Racing Team

Sled dogs aren’t simply hitched to a sled and off they go; rather, their long distance hauling is the product of teamwork and each dog has its own important role to play. First in line are the lead dogs who must set the pace, follow the musher’s commands and make important decisions. Like service dogs, they must have what’s called “intelligent disobedience”, the cognitive ability to disobey their musher’s command if following it would be counterproductive. An example? These dogs must be confident enough to disobey the musher’s directions if they find that it would cause them to run over bad ice or too close to a cliff, explains Jennifer Raffaeli, manager of Denali’s kennels in an article for National Geographic.

Second in line, are the swing dogs who follow the turns of the lead dogs ensuring those left or right turns go smoothly. Third in line are several team dogs who are responsible for maintaining speed. These dogs are the “muscles” pulling the sleds until ordered to stop. Last, but not least, are the wheel dogs. These dogs provide steering power. The best wheel dogs are careful to go wide on turns so to help guide the sled around trees and other obstacles, explains Howard Thompson, a former racer and now breeder of sled dogs nearby Mondovi, Wisconsin.

The Carriage Dogs

Back in time, carriage travel came with some risks. One big risk was being robbed by the highwayman, a thief who attacked coach travelers by horse. For protection, carriage dogs or coach dogs were employed. These dogs were trained to trot alongside the carriage protecting them from thieves. Should the highwayman try to attack, these dogs would attack their horses giving the travelers enough time to respond. While any breed of dog with long legs could have made a good carriage dog, Dalmatians soon became the breed of choice in the 18th century. Often more than one dog was used, especially by the most wealthy. It therefore wasn’t unusual to see some coaches accompanied by six to eight carriage dogs working as a team.

Bay and Catch Dogs

In the old days, boar and other animals were often hunted down and different types of dogs were sometimes employed to help the hunters locate them. The bay dogs (which were often hounds, curs or different crosses trained to find) would chase and circle the boar from a safe distance while baying. Their loud baying and howls alerted the hunter signaling that it was time to send out the “catch dogs,” which were dogs trained to catch and hold down the boar until the hunters arrived. An example of this teamwork can be found in the book “The Mammals That Moved Mankind: A History of Beasts of Burden” by R.C.Sturgis. According to the book, when wolves were hunted down, the scent hounds worked together to track down the wolf, and when the wolf was finally sighted, borzoi were then unleashed to hold down the wolves until the hunters arrived.

Guarders and Herders

When it comes to teamwork, two Hungarian breeds sure know how to pull things together. The puli is used to herd and guard livestock during the day, while the Komondor takes over and guards livestock during the night. Both dog breeds are known for having a unique corded coat that resembles dreadlocks. Their rastafarain looks are not there just to get heads turning, rather, their cords serve two distinct purposes: protecting their coats from the elements, and at the same time, protecting them from the potential bites of wolves. Indeed, should a wolf try to bite these dogs, it would take quite some effort to go through all those dreadlocks to reach their skin!

References:

Familiarity affects other-regarding preferences in pet dogs, Mylene Quervel-Chaumette et al, Scientific Reports 5, Article number: 18102 (2015)

R.C. Sturgis, The Mammals That Moved Mankind: A History of Beasts of Burden, AuthorHouse, 2015

Photo credits:

A fully corded coat. The coat is long, thick and strikingly corded Wiki.awal – Own work, Komondor dog breed CC BY-SA 3.0

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How Can Dogs Sniff Out Cancer?

June 27, 2016January 21, 2016 by Admin

It’s Talent Thursday, and today we would like to discover some more details about dogs who are putting their sniffers to work for a noble cause: detecting illnesses, in particular cancer. How do dogs detect cancer? Does cancer have a specific smell that dogs can discriminate from other smells? We have found some interesting findings on the subject, so we’ll be sharing them this Thursday in honor of our dog’s talented sniffers. So let’s take a look at our dog’s powerful sniffers, how they can help in detecting cancer and the type of training cancer-detecting dogs must go through.

A Powerful Sniffer

In order for dogs to detect cancer, several conditions must be met: the dog must have a sense of smell that is powerful enough to detect its smell, the cancer must release a distinctive smell that makes it stick out from other smells and the dog must be properly trained to let us become aware of it. When it comes to having a powerful sense of smell, there’s no doubt that dogs have powerful sniffers. While humans have only a mere 5 million olfactory receptors, it’s estimated that dogs have an outstanding 300 million. On top of that, the part of the dog’s brain responsible for analyzing odors is 40 times greater than ours. In the book “Inside of a Dog, What Dogs See, Smell, and Know,” Alexandra Horowitz, a cognitive scientist and researcher at Barnard College, offers a good example of how powerful those sniffers really are. While we are barely capable of noticing that our coffee has a teaspoon of sugar added to it, a dog is capable of detecting one teaspoon of sugar in a million gallons of water. That’s about the size of two Olympic-sized pools!

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Does Cancer Have a Smell?

So dogs have a powerful sense of smell, there’s no bones about that, but does cancer emanate a distinctive smell? This is not an easy question to answer since our poor sense of smell may not be powerful enough to detect such smells especially at its earliest stages. Sure, there are nurses and oncologists who claim to have smelled cancer in their patient’s breath, but this appears ot occur mostly in the most advanced stages. While there is some anecdotal evidence coming from dog owners claiming that their dogs showed a strong interest towards a specific spot or area on their skin that was later found to be cancer, the good news is that more and more promising, and most of all, “palpable” evidence is coming through.

Interesting details come from one of the latest studies published in the Journal of Urology. In this study, two female German shepherds trained for Explosion Detection were trained to identify specific volatile compounds in the urine samples of patients suffering from prostate cancer. The dogs were then tested on 362 patients suffering from prostate cancer and 540 healthy individuals that did not have cancer. Of course, further studies will be needed to further prove any potential predictive values for future use of dogs for this purpose, but overall the results were quite remarkable with both dogs showing promising abilities in detecting compounds associated with prostate cancer.

An Instinctive Behavior

When it comes to putting their powerful sniffers to work, dogs may retain an instinctive tendency to become interested in smells that suggest disease. This tendency may date back to the days when canines had to mostly fend for themselves. Predators by nature are attracted to prey animals that are sick or injured in some way, explains the InSitu Foundation, an organization that has been dedicated to scientifically training dogs to detect early stage cancer in humans for over 12 years. Sick, slow and injured animals are the most vulnerable and the easiest to be caught. After many years of hunting, predator animals learn to associate that “sick scent” with an easy meal so they’re naturally drawn to it. Even when dogs didn’t specifically hunt, but were acting more as scavengers, they were (and continue to be) attracted to the smell of sickness, disease or something rotting as this played a big role in their survival.

Perfecting the Training

Just because dogs are naturally drawn to certain smells, doesn’t mean that they are born knowing what to do when it comes to detecting specific odors. Dogs require extensive training in order to learn to detect and alert about the presence of compounds suggestive of cancer.

According to the InSitu Foundation the process is similar to training dogs to detect bombs and narcotics. The odor is simply paired with a high value reward, in a similar fashion as predators learn to pair the smell of a sick prey with an upcoming meal. Through repeated pairings, the conditioning process teaches dogs to become highly motivated to seek out that smell. However, it’s not that easy. If breath is being analyzed, the specific compound must be isolated as the dog needs to learn how to discriminate it from other smells in breath. This would require exposure to many samples so that the dog can be taught exactly what to look for. Finally, the dog must alert of its findings. Dogs may stop and sit down by the sample or they may lick the bottle to communicate that they have positively detected the scent of cancer cells. So things look promising so far in the cancer detecting department. According to UC Davis Health System, researchers have established that dogs are so far capable of recognizing melanoma as well as bladder, lung, breast and ovarian cancers. We shouldn’t therefore be surprised if one day we’ll see furry coats along with lab coats in future cancer diagnostic settings.

References:

Alexandra Horowitz, “Inside of a Dog, What Dogs See, Smell, and Know,” Scribner; September 28, 2010

Olfactory System of Highly Trained Dogs Detects Prostate Cancer in Urine Samples, The Journal of Urology, April 2015 Volume 193, Issue 4, Pages 1382–1387

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Dog Word of the Day: Neoteny

June 27, 2016January 20, 2016 by Admin

It’s Wednesday, which means it’s time for our weekly Dog Word of the Day! So today we opened up our encyclopedia on a random page and landed on the letter “N.” On that page we saw a picture of a baby and noticed the word “neonate,” which means “a newborn child or mammal” so we decided that our dog word of the day had to be the term “neoteny” which is closely related to the term neonate. What does a baby have to do with dogs? There are actually some interesting relationships between the looks of babies and how we perceive dogs. Read on to learn more.

The cuteness factor... — The cuteness factor…

So What is Neoteny?

So what is neoteny, and most of all, how does this term relate to dogs? Let’s first take a peak at the etymology of this term, shall we? The word neoteny is composed by the Greek word “neos” which means “young” and the word “teínein” which means “to extend.” According to Science Daily, neoteny is the retention of juvenile physical characteristics well into maturity. Also known as juvenilization, in evolutionary biology neoteny refers to the process behind the retention of baby-like, “neotenous” features such as larger eyes, bulging craniums, higher foreheads, smaller noses and smaller mouths. Some like to call it the cuteness factor!

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Neoteny in the Human World

Humans versus chimp skull — Human versus chimp skull

When it comes to humans, we can say that we are quite neotenous if we compare our facial features and overall bone structure with our closest living relative, the chimpanzee. According to Scientific American, more than resembling an adult chimpanzee, for decades scientists have noted instead how adult humans resemble infant chimps, but why would we retain infantile, baby-like traits? Interestingly, our looks could be a matter of a delay in development. When the development period of humans is compared to the development period of chimpanzees, humans showed marked differences.

For instance, while chimpanzees become sexually mature by the age of 8 or 9, humans take five more years, explains Ed Yong, in Science Blogs. Neoteny, the retention of juvenile traits, therefore occurs because of such delays in development, explains Philipp Khaitovich, molecular biologist of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. And it isn’t only a matter of looks, because neoteny also translates into an extended childhood, a time when our brain is particularly plastic, which provides the opportunity for our brains to further develop.

Neoteny in the Dog World

Interestingly, dogs also are quite neotenous creatures, especially when we compare their facial features and overall bone structure with their closest, ancestor, the wolf. Just as in humans, dogs appear to be more similar to wolf puppies than adult wolves, retaining puppy-like looks and behaviors well into adulthood. Their prolonged and slower juvenile period compared to wolves, allowed for a higher degree of plasticity and higher “trainability” compared to their wild relatives. As in humans, the juvenile period allows more flexibility and a better response to learning, explains Edward O. Price in the book “Animal Domestication and Behavior.” These neonatal traits have been cited as a result of domestication. (Fox, 1968) It’s important to note that these differences in developmental stages have set dogs and wolves so far apart that nowadays comparing dogs with wolves is somewhat like comparing humans to chimps. “Dogs possess social intelligence far beyond that of their wolf ancestors, and in many ways they’re more like us than our own primate relatives,” explains Brian Hare, founder of found the Canine Cognition Center at Duke University.

Further Changes Along the Way

As dogs shifted from the role of working dogs, to the role of companions, neonatal traits were further emphasized. Dog fanciers selectively bred for appealing traits such as flattened faces, large eyes, bulging craniums, shorter muzzles and floppy ears. All traits that make us ooohh and ahhh and that evoke all those warm and fuzzy feelings of dealing with cuteness and care taking. These traits are more pronounced in certain breeds such as the cavalier King Charles spaniel, Pekingese, pug and French bulldog.

“Humans feel affection for animals with juvenile features: large eyes, bulging craniums, retreating chins (left column). Small-eyed, long-snouted animals (right column) do not elicit the same response.”~Konrad Lorenz

While the effects of neoteny are quite interesting, one must remain with an open mind as the subject is still under scrutiny as we gain more and more insights about the developmental process of both humans and dogs. Different theories abound as we await more clarifications about the exact genetic mechanisms.

References:

Mitteroecker P, Gunz P, Bernhard M, Schaefer K, Bookstein FL (June 2004). “Comparison of cranial ontogenetic trajectories among great apes and humans”. J. Hum. Evol. 46 (6): 679–97.doi:10.1016/j.jhevol.2004.03.006. PMID 15183670

Collins, D. et al. (1973). Background to archaeology: Britain in its European setting. Cambridge: Cambridge University Press. ISBN 0-521-20155-1 hard cover

Cognitive and Physical Development and Domesticity in Dogs

Photo credits:

Neoteny and reduction in skull size – grey wolf and chihuahua skulls, photo by Dmccabe, Wikipedia, CC BY-SA 3.0

“HUMANS FEEL AFFECTION for animals with juvenile features: large eyes, bulging craniums, retreating chins (left column). Small-eyed, long-snouted animals (right column) do not elicit the same response.” –Konrad Lorenz photo by Ephert Wikipedia, Creative Commons Attribution-Share Alike 4.0 International license.

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Why Does Dog Urine Kill Grass?

June 27, 2016January 19, 2016 by Admin

It’s Tuesday Trivia, are you ready to test your canine expertise? Today’s question revolves around the fact that dog urine kills grass. If you are a dog owner and own a yard, you may have likely seen the unsightly effects dog urine may have on grass. The urine may cause the grass to turn yellow, brown and wilt creating a bizarre crop circle problem, but why is that? There have been some myths surrounding the issue as to why dog urine kills grass, so we have conducted some research on the topic and found some interesting findings. So today’s question is:

Why Does Dog Urine Kill Grass?

A) Because of the pH level of dog urine

B) Because dog urine contains nitrogen

C) Because dog urine is too acidic

D) Because dog urine is too warm

Answer: if you answered A, consider that this answer sounds quite reasonable considering that there are still several websites claiming that it’s a matter of pH, but we found some reputable resources stating that it’s not true. According to The University of Wisconsin-Extension Network: “Dog urine has a pH between 6.0 and 8.0, depending on the dog’s diet and health. It is NOT the pH of the urine that kills the grass.” If you answered C, that the urine is too acidic, consider again that an acidic pH has little to do with its ability to kill grass. The University of Winsconsin explains that for this reason it’s pointless giving dogs acidifying agents such as tomato juice or vinegar for the purpose of preventing damage to grass. If you answered D, well, a dog’s urine may be on the warm side, but its temperature is not hot enough to kill grass. So the correct answer is B. Turns out, it’s a matter of nitrogen. According to Colorado State University, we must blame waste products such as nitrogen-containing compounds and salts contained in dog urine which result in the damage to our lush lawns. For more on why dog pee kills grass and helpful tips to deal with the problem, read Why Do Dogs Kill Grass When They Pee?

References:

Allard, AW. Lawn burn and dog urine, Canine Practice, March/April 1981;8;(2);26-32.

Colorado State University Extension Horticulture Agent, Larimer County; and Tony Koski,PhD, Extension Turf Specialist, Department of Horticulture & LA, Colorado State University

The University of Wisconsin-Extension Network: Lawns and Dogs But Not Tomato Juice, Courtesy of Diana Alfuth, Horticulture Educator, Pierce County UW Extension

Texas AgriLife Extension Service, Aggie Horticulture, Dog On It Lawn Problems, by Dr. Steve Thompson, DVM – DirectorPurdue University Veterinary Teaching Hospital Wellness Clinic

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I am Your Dog’s Adrenal Glands

June 27, 2016January 18, 2016 by Admin

It’s Monday Marvels, and today we will be introducing the dog’s adrenal glands. Like some other dog body parts that for the most part live in the shadow, you likely don’t hear much about the adrenal glands unless they start giving problems. In dogs, the adrenal glands are responsible for secreting important hormones, but sometimes things can get a bit out of whack in the hormonal department. By getting more acquainted with these glands, we can better understand their important role in a dog’s overall state of health and sense of well being. So for Monday’s Marvels let’s see what the adrenal glands have to say.

Introducing Your Dog’s Adrenal Glands

Hello, it’s your dog’s adrenal glands talking! Our name derives from the fact that we are located right in front of your dog’s kidneys. The term “renal” indeed comes from the Latin word “renes ” which stands for kidneys” while the prefix “ad” comes from the Latin word “near.” Therefore put 2 and 2 together and you’ll figure out that adrenal means “near the kidneys.” At a first glance, if you look at our structure we may look like two glands, one on the left, and one of the right, but actually, we’re made of some distinct parts. To better give you an idea, imagine a chocolate-covered peanut. The peanut being one part (the adrenal medulla), and the chocolate on top being another, (the adrenal cortex). That’s how we are structured. What are our main functions? We actually have several, so hold tight as here are some.

Implementing the Fight or Flight Response

The adrenal medulla, the inner peanut portion of us, is responsible for secreting the hormones epinephrine (adrenaline) and norepinephrine (which increases blood pressure) into your dog’s bloodstream. You see, when your dog feels threatened from something, his sympathetic nervous system kicks in, triggering what is known as the “fight or flight response.” Basically, his body gets in a hyper reactive state so it’s ready to spring into action and up his chances for survival. For the sake of comparison, it’s that short-term stress reaction you may feel when you’re camping and see a bear that has come too close for comfort.

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Your dog’s heart will therefore beat faster, his blood pressure rises, the airway passages dilate, blood is sent to the muscles and his senses become more acute. At the same time, his gastrointestinal function decreases, which is why he may not be interested in that slice of baloney you dangle in front of his face when he’s extra worried about something. Even after the scary event has passed, it may take some time for your dog’s body to recover from such an excited state considering that these hormones tend to stick around in the bloodstream for some time.

The Adrenal Cortex

The outer portion of us, the adrenal cortex, comprises several layers, with each layer being responsible for different tasks. To have a better idea, imagine our outer portions as the layers of an onion. My outermost layer is the zona glomerulosa, then, sandwiched somewhere in between is the zona fasciculata, and finally, our inner portion is the zona reticularis. To have a better idea, see the picture on the side. Now, let’s take a closer look at the different roles these layers play, shall we?

Raising Your Dog’s Blood Glucose

The zona fasciculata, the middle layer, is responsible for producing glucocorticoid hormones. These hormones include cortisone, cortisol and corticosterone which share the ability to raise your dog’s levels of blood glucose, maintain blood pressure and help the body deal with the effects of stress. Glucocorticoids also act as natural steroids, suppressing any inflammatory and immunologic responses.

Regulating Your Dog’s Minerals and Salts

The outermost layer, the zona glomerulosa, is responsible for regulating the amounts of important electrolytes under the form of minerals and salts in the body. Aldosterone, the main mineralocorticoid hormone, regulates the right balance of salt, potassium and water and helps control blood pressure. You see, when levels of potassium are too high, they must be lowered as potassium can become toxic at high levels, so aldosterone works on keeping its levels under control.

Producing Dog Sex Hormones

Finally, the inner most layer, the zona reticularis, is responsible for the production of small amounts of the sex hormones androgen, progesterone and estrogen.

When Things Go Out of Whack

While I try to do my best in producing hormones as needed, sometimes things can get out of whack. If my adrenal cortex happens to produce too much cortisol, affected dogs may develop what is known as “Cushing’s disease,” also known as hyperadrenocorticism. In a normal, healthy dog, a normal amount of cortisol helps the body adapt in times of stress and regulates proper body weight and tissue structure, but too much of a good thing leads to the weakening of the dog’s immune system and a predisposition to infections and disease, explains Ann Stohlman, a veterinarian working for the FDA’s Center for Veterinary Medicine. Why do I produce so much cortisol? Good question! The Merck Manual states that 85 to 90 percent of the time, it’s due to a tumor in the pituitary gland. Less commonly it’s due to either a tumor in my glands or the long term use of steroid drugs.

If instead, my adrenal cortex produces too little adrenal gland hormones, affected dogs may develop what is known as “Addison’s disease,” also known as hypoadrenocorticism. Why do I produce too little of these hormones? In this case, we can blame some auto-immune condition, where the dog’s body mistakenly destroys some of its own tissues, infections in the gland or some form of cancer. When I secrete too little aldosterone, the levels of potassium, sodium, and chloride in the dog’s bloodstream are no longer regulated and we already talked about how toxic potassium can be if there’s too much.

Did you know? Dogs can be also prone to adrenal fatigue. According to veterinarian Randy Kidd, chronic overstimulation of the adrenal glands may lead to adrenal fatigue and other conditions such as diabetes mellitus or heart failure.

References:

Merck Vet Manual: Disorders of the Adrenal Glands in Dogs

Clinical Anatomy & Physiology for Veterinary Technicians, Thomas Colville DVM, Joanna M. Bassert VMD, Mosby Inc. St Louis, MO, 2002

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What Makes Dogs Good Running Partners?

June 27, 2016January 17, 2016 by Admin

For those folks looking for good running partners, what’s better than a dog? Other than some teeny lap dogs, short-faced dogs who have trouble breathing and overheat, and a few couch potato breeds that would rather snooze than go for an outdoor romp, many dogs make suitable running partners who would say “woof!” without hesitation if they were asked to go for a nice jog with their favorite humans. Sure, dogs have energy, they like to spend times outdoors and they’re willing to accompany their owners just about anywhere as long as it’s a fun place to be, but what really makes dogs good running partners? Let’s delve deeper into what makes dogs particularly adept to making great running partners.

Dogs are Cursorial Animals

Let’s face it, some animals appear to have been purposely crafted for running. A cursorial animal simply means that its body has specifically adapted for the purpose of running. Running for what though? It depends. Cursorial grazers such as horses relied on running to escape predators and to cover lots of ground in search of optimal pastures; whereas cursorial predators such as wolves relied on running for chasing and catching prey. Examples of cursorial animals therefore include dogs, cats, horses and gazelles. What do these animals have in common? They have developed longer legs and their bodies have undergone adaptations to allow them to effectively run under the form of longer legs, modified feet and the development of hooves, according to the Museum of Osteology.

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Dogs are Digitigrade Animals

While humans are plantigrades who walk on the soles of their feet, dogs are digitigrades, which means that they walk on their toes. We often think of a dog’s paws as their hands and feet, when in reality we are mainly looking at their toes as seen in these illustrations. The bones that correspond to our wrists and ankles are set much higher than we would think which explains why many people often confuse the dog’s ankles (hocks) for the dog’s knees (stifle). This explains why many artists have difficulty in drawing animals and develop “backward knee syndrome,” explains Kim B. in a blog for artists.

One big perk of being digitigrade is that walking on the toes allows them to move around more quietly and attain faster speeds, explains Theresa A Fuess, a veterinarian working for ‎Veterinarian at Lakehills Animal Health. Other animals classified as digitigrades include wolves, coyotes, bobcats and foxes, adds Mary Hoff, a freelance science writer in an article for the Minnesota Department of Natural Resources.

A Word of Caution

Sure, many dogs have the potential to make wonderful running partners, but it’s always best to practice caution to prevent potential injuries to our four-legged friends. A good place to start is by looking at the dog’s age. Many people get a puppy and can’t wait to start jogging with him, but it’s best to consult with a vet first as to when to take the pup along. Just as in children, a puppy’s skeletal system is developing, and starting an inappropriate exercise regimen too soon can cause potential damage to the puppy’s growth plates. Growth plates are soft areas of developing cartilage tissue that are found at the ends of the puppy’s long bones. If too much exercise or the wrong type is implemented before the growth plates harden and close, they are vulnerable to being injured and potentially fractured. An injury to the puppy’s leg during this time may result in lots of damage and potential deformity, warns veterinarian Karen Becker. Consider that for large breeds skeletal maturity is reached at a later age (generally 18 months to 2 years) compared to smaller dogs, cautions veterinarian Chris Zink, a canine sports medicine and rehabilitation specialist. Consult with your vet for specific recommendations.

Another issue, when choosing dogs as running partners is failing to properly condition them to an exercise regimen. Just as in human athletes, slow and steady is the way to go. Sure it doesn’t take dogs too long for them to attain a good conditioning level as their physiology is designed for endurance, but starting slowly and gradually helps lay out the groundwork and ups the chances for success, suggests, Robert Gillette, veterinarian and director of Auburn University’s Veterinary Sports Medicine Program. Again, best to consult with a vet for the best exercise program for your dog.

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Is Peanut Butter Bad For Dogs? Watch Out for These Brands!

March 15, 2022January 16, 2016 by Admin

It’s surprising Saturday and today we thought it’s quite surprising that a food as innocent as peanut butter can be potentially harmful to our dogs. Truth is, not all peanut butter is created equal and there are certain types of peanut butter which can actually be very bad for dogs. Most dogs love peanut butter and many dog owners love to give peanut butter to their dogs as a tasty treat. Whether you use peanut butter to stuff your dog’s Kong, help your dog take his medication or you simply have to let your dog lick some off your spoon after eating a peanut butter and jelly sandwich, if you haven’t done so already, it’s time to start checking those labels before feeding peanut butter to Rover again next time.

A Dangerous Ingredient

As more and more people are trending towards health conscious choices, we see more and more products crafted to match this trend. There are many companies that have chosen to make sugar-less products for those folks trying to lose weight or make healthier choices, but just because products are being crafted with these people in mind, doesn’t mean that these products are suitable for dogs. In DVM360’s article on the Biggest News of 2015, the news that certain types of peanut butter aren’t considered safe for our dogs has been warranted a prime position.

The main problem with some brands of peanut butter is not the fact that they are sugar free per se, but the fact that they use the ingredient xylitol. While xylitol’s low glycemic index makes it appealing for humans, in dogs, this sugar alcohol is known for causing dangerous conditions such as hypoglycemia and hepatic necrosis.

Brands known for using xylitol so far include Nuts ‘n More , Krush Nutrition, and P-28 Foods, but more brands may be using this harmful ingredient already, and more so in the near future, so it’s always best to practice caution and always read labels, recommends veterinarian Dr. Ahna Brutlag.

Signs to Watch For

What symptoms does xylitol toxicity cause in dogs? According to the Pet Poison Helpline, symptoms suggesting a dog may have ingested toxic amount of xylitol include the following:

Lethargy
Weakness
Vomiting
Black, tarry stools
Jaundice
Tremoring
Seizures
Collapse
Coma
Death

Anybody suspecting their dog may have ingested a product containing xylitol should contact their veterinarian or the Pet Poison Helpline at 855-764-7661 at once (a $49 per incident fee applies, so have your credit card ready). Time is of the essence considering that ingestion of as little as > 0.1 gram/kg can potentially cause a life-threatening episode of low blood sugar within 10-15 minutes, explains the Pet Poison Helpline. Larger doses may trigger acute liver necrosis and liver failure. Xylitol isn’t restricted to peanut butter. It can also be found nowadays in several other products such as chewing gum, mint, pudding, gelatin, candy, snacks and toothpaste.

Other Health Concerns

Are peanuts safe for dogs? While peanuts are not considered toxic to dogs, they aren’t totally safe either. Here are some issues with giving peanuts and peanut-related products to dogs. One issue is the fat content of peanuts, so peanut butter can be become troublesome in dogs prone to developing pancreatitis, a serious condition known for causing persistent vomiting that generally requires extended hospital stays, warns veterinarian Dr. Rachele Baker.

Peanut butter should also be used with caution in dogs with heart conditions due to its salt content. Those who use peanut butter to give heart medications to their dogs should look for peanut butter labeled as “no salt added” suggests the Nestlé Purina Pet Care Company. Finally, another issue to consider is the amount of calories in peanut butter. If you are trying to get Rover to shed some pounds, consider that just 1 tablespoon of peanut butter has the same amount of calories as 3 cups of air-popped popcorn without butter, according to an article by Today’s Veterinary Practice.