January 2016 - Page 2 of 4 - Daily Dog Discoveries

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.

Understanding the Chihuahua’s Molera

June 27, 2016January 15, 2016 by Admin

Today we thought it was quite interesting learning more about a Chihuahua’s “molera,” a unique trait of this pint-sized pet. While once it was considered a mark of purity in the breed, and at some point, even a defect, today a better understanding of this “soft spot” reveals that it’s simply a characteristic of the breed, perhaps just as unique as the spots on a Dalmatian or the ridge on a Rhodesian ridgeback. However, unlike spots or ridges, the molera is not seen on all Chihuahuas, and if it’s present, it’s often destined to shrink and possibly disappear within a certain time frame. OK, for those folks who have never heard about a molera and are dying to know, what is a molera in the first place? Read on to learn more.

What on Earth is a Molera?

In its simplest definition, the molera is a “hole” in the Chihuahua’s head. When Chihuahuas are still in the womb, the bones in their heads are not fused together as they should be, so when they’re born, they have this “hole” on the top of their heads between the ears which is called “molera.” The molera isn’t unique to Chihuahuas. Human babies have something similar too, but in human babies these soft spots on a baby’s head are known as “fontanelle.” The American Kennel Club mentions the molera in the Chihuahua’s breed standard when referring to the Chihuahuas’s head. According to the Chihuahua breed’s standard the head should have: “A well rounded “apple dome” skull, with or without molera.”

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What’s Its Purpose?

Why do some Chihuahua puppies have a soft spot on their head? Not all Chihuahuas have them, but many toy breeds are born with a palpable open fontanelle. The molera is there for an important purpose: it helps the puppy pass through mother dog’s birth canal safely. In small breeds, the mother dog’s birth canal is very narrow, yet, those puppy heads are quite big. The gap in the head therefore allows the puppy’s head to pass through without too much pressure being applied on the skull and brain. The molera therefore allows the pup’s bony plates of the skull to flex upping the chances for an uneventful birth. However, due to their conformation, it’s not unusual for Chihuahua mothers to require a C-section.

At the puppy grows, the bony plates of the skull gradually grow around the brain, becoming less soft and eventually ossifying. When do puppy soft spots close? Once the puppy is born, the molera should gradually close on its own generally by the age of 9 to 12 weeks. In certain breeds like the Chihuahua or miniature dachshund though, it may remain permanently open without any particular consequences, explains veterinarian William D. Fortney. However, it’s best to avoid pushing on the area as there is no protection for the brain, adds veterinarian Dr. Tammy. If the open fontanelle is large, some owners have found it helpful to protect these vulnerable spots with helmets.

Not as Bad as Thought

It was once thought that a domed head and the presence of a soft spot was associated with a medical condition known as “hydrocephalus,” where cerebrospinal fluid accumulates in the brain making it swell and triggering neurological signs. However, according to a study conducted by Greene and Braund in 1989, “Many clinically normal toy breeds and brachycephalic (short faced) breeds also may have open fontanelle without associated hydrocephalus. There did not appear to be any relationship between the presence or size of the fontanelle and the concomitant presence of hydrocephalus.” The Canine Inherited Disorders Database web site seems to agree, according to the website, “an open fontanel is not diagnostic per se of hydrocephalus, as it may occur in a normal healthy dog. ”

References:

Chihuahua Club of America: Molera Statement

Chihuahua Club of America: Understanding Differences Between a Molera and Hydrocephalus

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The Neuroplasticity of a Dog’s Brain

July 23, 2016January 14, 2016 by Admin

What’s more talented than a dog’s brain that is always in a learning state? We often think of the puppy’s sensitive period as a window of time that permanently “shuts close” once the time frame has elapsed, but sometimes we forget that dogs are always learning. Saying that the window of opportunity for puppy socialization closes shut within a certain time frame ignores the beauty of the neuroplasticity of a dog’s brain. Rather than closing shut, a more accurate description may be that the opportunity to absorb and retain may be significantly diminished, as there is always space for new neural connections to be formed, things just become more challenging past a certain time frame, experts say.

Like Learning a New Language

Don't miss out the puppy socialization period! — Don’t miss out the puppy socialization period!

Nicholas Dodman in the book “Puppy’s First Steps” compares it to the uncanny ability children are blessed with in learning new languages. When a child is young, he’s very adept in grasping the accent, intonation and use of idiomatic expressions of a new language which explains the easiness of children to becoming multilingual, but over time, the brain loses its flexibility so the ability to learn a new language tends to fall dramatically with advancing years. Sure, you can make up for the lost ground once the pup is a 6 month-old teenager, but it will require much more effort, just as with learning a new language at a later age.

Plasticity of the brain is something that occurs over a lifetime, the brain never stops changing and adjusting, but the level of plasticity tends to change during certain periods of one’s life. It’s best to reap the benefits of this time and socialize puppies properly rather than enduring in “remedial socialization”. The American Veterinary Society of Animal Behavior’s Position Statement on Puppy Socialization emphasizes the importance of providing ample of positive socialization opportunities during the puppy’s first three months of life.

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old dog learns tricks — Keep that brain stimulated!

Old Dogs Learn New Tricks!

What does neuroplasticity mean though exactly? The term “neuro” refers to nerves of the nervous system and the term plastic comes from the from Greek word “plastikos,” from “plassein” which means ‘to mold.’ And both our brains and the brains of our dogs are always in the the process of being “molded” in some sort of way. This occurs when we we learn something new or retain some new information that causes new neural connections which make our brains capable of neuroplasticity.

It was once thought that our brains had a lowered ability to create new neural pathways beyond the juvenile period, a time frame during which it’s particularly suited to neuroplastic adaptation, but new studies have shown that even the brain of the elderly is capable of being plastic. “Neuroplasticity never ends, you can in fact teach an old dog new tricks, it just might take a little longer,” claims Shelli R. Kesler a senior research scientist at Stanford University School of Medicine.”

“We used to think that the brain was completely formed by development and its basic structure didn’t change much in adults, but as research went on we discovered that wasn’t true. We now know that an underlying portion of the brain called the thalamus, which feeds the cortex information from our senses, is remarkably plastic. Using new research techniques on rats, our lab found that the neuronal connections bridging the thalamus to the cortex are massively plastic—they grow and retract rather rapidly in only a few days in response to different sensations we expose the rat to,” further explains Randy Bruno, Assistant Professor of Neuroscience and member of the Kavli Institute for Brain Science at Columbia University.

Off the Beaten Path

To better understand the concept of neuroplasticity, Team Neuroplasticity compares the formation of new neural pathways to taking a walk in the woods. It’s as if we tend to walk the same paths during our daily activities each day. Then, one day, we’re attracted by something and decide to stray and go off the beaten path. We discover new intriguing trails, and as we start walking them every day, these fresh paths start to get worn and easily noticeable so we start navigating them with ease. With enough repetition, we can even travel them as if we are on autopilot. This is similar to what happens when we learn something new courtesy of the neuroplasticity of our brains. Same goes on with dogs. Teaching a new trick or a new skill and providing environmental enrichment is beneficial to our canine companions. “Enrichment is an essential component of care for all pets, including small mammals, reptiles, dogs, cats, and horses, and can have a positive effect on their welfare and well-being” claims veterinary behaviorist Lisa Radosta with Florida Veterinary Behavior Service Jupiter, Florida.

Did you know? It was English neurophysiologist Charles Scott Sherrington the first to coin the term “synapse” the gap between two nerve cells, in 1897.

References:

Angeline S. Lillard, Old dogs learning new tricks: Neuroplasticity beyond the juvenile period,Developmental Review, Volume 31, Issue 4, December 2011, Pages 207–239

Nicholas Dodman “Puppy’s First Steps: Raising a Happy, Healthy, Well-Behaved Dog ” Cummings School of Veterinary Medicine at Tufts University Wilmington, Massachusetts, Houghton Mifflin, July 24, 2008

Sanjay Gupta, Chasing Life: New Discoveries in the Search for Immortality to Help You Age Less Today, Thorndike Press, 2007

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Dog Word of the Day: Dolicocephalic

June 27, 2016January 13, 2016 by Admin

It’s Wednesday Word Day! Today we randomly opened our Encyclopedia and stumbled on the word “dolicocephalic.” This word may sound a bit complicated, but once we break it into smaller components, it becomes easier to understand. Chances are, you might even own a dolicocephalic dog breed too! This term though isn’t restricted to the dog world only, there are also many dolicocephalic cats and some delicopehalic rabbits too! So let’s take a closer look into this word and discover some intriguing facts about the dog word of the day: “dolicocephalic.”

A Lesson in Etymology

What does the word dolicocephalic mean? Let’s take a look at the history of this word. Merriam Webster tells us that the word derives from the Greek word “dolichos” which means long and “kephalos,” which means head. If you put the two words together, you have “long head,” therefore, dolicocephalic in the dog world pertains to certain types of dogs where the length of the head is greater than its width. This is the total opposite of dogs who are brachycephalic, meaning short-headed.

Dolicocephalic: long-headed	Brachycephalic: short-headed

What Teeth You Have!

Dogs with long heads may share some interesting traits that makes them quite different than other dogs. If you look at their teeth, their longer jaws can make them appear as if they have gaps between one tooth and another. This is called “diastemata” which means “a space or gap between two teeth.” In some cases, the space may be so wide that to some people it may appear as if they are missing teeth, but they are not, explains Dr. Cedric Tutt, a Veterinary Specialist in Dentistry in South Africa in the book “Small Animal Dentistry: A Manual of Techniques.”

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What Eyes You Have!

Many dogs with dolicocephalic heads share some common traits: they may have a history of being selectively bred to have an exceptional eye sight and are very fast. Sight hound breeds like the saluki, borzoi, greyhound and Afghan hound, were selectively bred for catching fast prey, therefore it shouldn’t be surprising if their facial conformation allowed a wider field of vision so they could better spot prey. Their almond-shaped eyes are set wide apart. It has been noted that distribution of retinal ganglion cells is correlated with nose length, something particularly important in sight hounds as they needed to be scanning the horizon for prey over vast open landscapes.

A Nose For Problems

According to the book “The Dog and Its Genome,” dolicocephalic dog breeds are prone to problems related to the shape of their heads such as nasal tumors and mycotic rhinitis. Another potential problem dolicocephalic breeds may be predisposed to is aspergillosis, a respiratory infection that is typically localized to the dog’s nasal cavity and known for causing lethargy, pain and ulcerations on the nostrils, sneezing, nasal discharge and nose bleeds, according to the Merck Veterinary Manual.

Did you know? Because sight hounds have narrow heads, they can easily slip out of regular buckle collars. Many trainers suggest using martingale collars (also known as greyhound collars) for dolicocephelic dogs. When fitted correctly, these collars work well as they’re less likely to slip over the dog’s head, explained the late internationally-acclaimed veterinarian, animal behaviorist, Dr Sophia Yin.

References:

Miller P. E., Murphy C. J, 1995 Vision in dogs. J. Am. Vet. Med. Assoc. 207: 1623–1634.

McGreevy P, Grassi T. D, Harman A. M, 2004A strong correlation exists between the distribution of retinal ganglion cells and nose length in the dog. Brain Behav. Evol. 63: 13–22

The Genetics of Canine Skull Shape Variation, , GENETICS February 8 , 2013 vol. 193 no. 2 317-325 (Early Online February 1 , 2013).

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The Dog Version of Fingerprints!

June 27, 2016January 12, 2016 by Admin

It’s Tuesday Trivia, which means it’s time to test your canine knowledge! Today, we’ll be tackling a dog’s body part that is so unique it can be said that it’s capable of replicating the equivalent function of a human fingerprint. Indeed, its pattern can be used to identify dogs, distinguishing one dog from another. What body part are we talking about it?

A Dog paws

B Dog toes

C Dog noses

D Dog tongues

And the answer is:

Answer: if you answered A, nope, dog paws can have a unique smell of Frito feet, popcorn or tacos, but the paw prints they produce don’t have a pattern that allows them to be similar to producing our fingerprints. If you answered B, it makes sense to say toes as they’re as close as you can can get to the digits of our fingers, but no, it’s still not the correct answer. If you said D, dog tongues, sure our doggy’s tongues leave some unique patterns on our clean windows and glass sliding doors, but no, that’s not the answer we were looking for. So the correct answer is C, dog noses!

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If we take a close look to our dog’s noses, we will see that on their surface there are several ridges that form patterns. The moist texture of this surface is meant to attract odor molecules allowing the dog to smell them easier, explain D. Caroline Coile and Maragaret H. Bonham’s book “Why do dogs like balls?” Well, the intriguing part is that it has been discovered that these ridges on the dog’s nose are so unique that their appearance could be used as a way for identifying dogs.

According to a study, taking nose prints in dogs is a fairly easy process. All that’s needed is to dry the nose with a lint swab, impregnate the leather of the nose with China ink and a nose print is then printed on a white cardboard. Voila!

Did you know? The moist, naked part of the dog’s that we commonly refer to as “nose” has a technical name, it’s called “rhinarium.”

References:

D. Caroline Coile, Maragaret H. Bonham’s book “Why do dogs like balls? Sterling Publishing Co. Inc, New York, NY, 2008

N. Coldea (1994) Nose prints as a method of identification in dogs, Veterinary Quarterly, 16:sup1, 60-60, DOI: 10.1080/01652176.1994.9694497

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