Category archives: Ask The Vet

Degenerative Myelopathy- Should Yorkshire Terrier Lovers Be Concerned?

Degenerative Myelopathy- Should Yorkshire Terrier Lovers Be Concerned?

The adorable Yorkshire terrier has become an important fixture in American households since its introduction to the United States in the late 19th century. Originally bred in Scotland and going by the name “Scotch terrier”, the Yorkshire terrier was given its modern name after great improvements in the breed were made in the county of Yorkshire in northern England.

Like most dog breeds, the Yorkie has developed some inherited diseases on its path to the modern breed. The genetic mutations responsible for some better known, inherited diseases of Yorkies such as primary lens luxation (PLL) and a form of progressive retinal atrophy known as progressive rod-cone degeneration (PRA-prcd) have been identified. The identification of these mutations has made it possible for Yorkie breeders to test their dams and sires prior to breeding and to use informed selective breeding practices to prevent the birth of puppies with these conditions. While most Yorkie breeders are familiar with PLL and PRA-prcd in the breed, another inherited condition known as degenerative myelopathy (DM) is less well known by Yorkie breeders. However, DM may be a concern worth investigating further in the Yorkie as the associated mutation has been identified in the breed.

What ...

Preventing Inherited Von Willebrand Disease in the Kerry Blue Terrier

Preventing Inherited Von Willebrand Disease in the Kerry Blue Terrier

The Irish-bred, Kerry blue terrier (KBT) is historically a well-rounded working dog with its roots in hunting small game and rodents. However, their intelligence and diverse abilities have also led to their success as guard dogs and as a herding breed. Like many terriers, the KBT is known for its high energy and tends to benefit greatly from daily exercise. Though early KBTs were often selected for their tenacity and aggressiveness to perform their duties as hunters and guard dogs, these attributes historically made them less suitable companions for other dogs. However, modern breeding efforts have focused on maintaining their high energy while decreasing tendencies toward aggression.

One of the most striking attributes of the KBT is their characteristic hair coat. Kerry blue terriers are born black, but develop their beautiful, soft and wavy blue/gray coat during the first two years of life in a process of color fading, commonly referred to as “clearing”. Dogs displaying black coloration on the body after 18 months of age are disqualified from the AKC show ring. However, black on the extremities (muzzle, head, ears, tail, and feet) is allowed at any age.

This spirited breed, though relatively healthy, has developed some inherited disease concerns ...

Preventing Inherited Congenital Stationary Night Blindness in the Briard

Preventing Inherited Congenital Stationary Night Blindness in the Briard

With depictions in artwork from as early as the 8th century, the ancient Briard is a French dog breed that has been employed in diverse roles throughout its history, but is most commonly recognized as a herding breed or as a guard dog for flocks of sheep. Though documentation of its early history is sparse, the first breed standard for the Briard was written in the late 19th century and the breed was accepted for registration by the AKC in 1922 after being brought to North America from Europe (including Briards imported by Thomas Jefferson). Praised for their intelligence and memory, the Briard is a naturally protective dog that can benefit from early and extensive socialization in order to establish proper boundaries and temperament toward strangers. They are often regarded as extremely loyal and bonded to their owners and appreciate significant time with their human “pack”. Though the breed is regarded as relatively healthy, as with most purebred dogs, the Briard has developed some inherited disease concerns during its path to the modern state of the breed. One of the best known Briard inherited disease concerns, unique to the breed, is a disease known as congenital stationary night ...

Preventing Inherited Progressive Retinal Atrophy in Poodles

Preventing Inherited Progressive Retinal Atrophy in Poodles

Despite their characterization in popular culture as a gorgeous, yet delicate dog breed with more beauty than brawn, the ancestors of today’s poodles (especially standard poodles) were revered for their ability to work. Still well known for their exceptional intelligence, the standard poodle (the oldest poodle variety), was commonly used as a gun dog and water retriever to assist European hunters. Portrayed in drawings and paintings from as early as the 15th century, the standard poodle was eventually bred to smaller breeds in order to create poodles of smaller size. The resulting smaller dogs, which reportedly disliked water, were used for truffle hunting and formed the ancestry of today’s toy and miniature poodle breeds. Though no longer commonly thought of as gun dogs, interest in using standard poodles as hunting dogs has reemerged with some standard poodles experiencing success in AKC and CKC hunting trials since the mid to late 1990’s. Toy and miniature poodles are most commonly recognized today as family-friendly companion dogs. During their path of development, like other purebred dogs, all three commonly recognized varieties of poodles have developed some inherited diseases that can make life challenging. One particular disease of poodles known as progressive retinal ...

The Path to Independence from Canine Inherited Diseases

The Path to Independence from Canine Inherited Diseases

The art of medicine today is nearly unrecognizable from its state in 1776 when the original thirteen colonies of the United States declared their independence from Great Britain. Without knowledge of bacteria or viruses, physicians and veterinarians of the day had few worries about sterility or the fact that they could play a role in the spread of deadly diseases between their patients. Bolstered by anecdotal evidence, dangerous treatments to purge various ailments from the body such as bloodletting and enemas (then called clysters) were commonly practiced in both people and animals in opposition to our modern understanding of their risks and lack of efficacy.

The Birth of Modern Genetics

The 19th century saw great advances in science including progression of the scientific method by which scientists could more objectively test their observations and develop an explanation for them. These methods also allowed for the modification of previous theories as new information was uncovered through experimentation. It was also the 19th century in which the foundation for the modern era of genetics was laid by an Augustinian friar named Gregor Mendel. Far ahead of his time, Mendel’s study of trait inheritance in the common pea plant went relatively unnoticed ...

Preventing Inherited L-2-HGA in the Staffordshire Bull Terrier

Preventing Inherited L-2-HGA in the Staffordshire Bull Terrier

Despite its 19th century reputation as a ferocious and fearless competitor in the cruel sport of dog fighting, the modern, well-bred Staffordshire bull terrier (SBT) is an affectionate, friendly, and loyal companion. At only 24 to 38 pounds, the SBT’s impressive, muscular frame is now a relic from a distant time when dogs slept in the backyard instead of the bedroom and often proved their worth through the use of their agility, strength, tenacity, and teeth. Through nearly a century of careful selective breeding for temperament, the SBT has become as suitable for the family as they once were for the fighting ring. As with other purebred dogs, along the path of breed improvement, the SBT has developed some inherited diseases that have caused problems for SBT owners and breeders alike. One of the most concerning inherited diseases in the SBT is the neurometabolic disorder commonly referred to by the acronym L-2-HGA; short for L-2 hydroxyglutaric aciduria.

What is L-2-HGA?

Dogs affected with L-2-HGA lack functional copies of a protein important in eliminating L-2 hydroxyglutaric acid (a normal product of metabolism) from the body. As a result, L-2 hydroxyglutaric acid accumulates in the urine, blood, and cerebrospinal fluid. Though ...

Preventing Inherited Urate Bladder Stones in the Bulldog

Preventing Inherited Urate Bladder Stones in the Bulldog

Though the cruel bull-baiting practices for which the ancestors of bulldogs were used have long passed, the enthusiasm for the modern bulldog as a friendly companion animal is as fervent and robust as ever. Ranked the 4th most registered dog in the AKC, it’s no secret to most that the bulldog has established itself as one of America’s favorite canines. Through selective breeding practices, the previously fierce and aggressive bulldog of old has given way to a gentle, even tempered, yet strong willed breed with copious amounts of character; in both temperament and physical attributes. Unfortunately, like other purebred dogs, during the course of breed development, some inherited genetic diseases have come to light that can make life difficult for bulldogs and those that love them. Luckily, through the use of genetic testing technologies and selective breeding, some of these inherited diseases can be completely eliminated (or greatly reduced in frequency) from blood lines. One example of an inherited disease that can now be prevented in the bulldog is an inherited form of urinary stones known as hyperuricosuria (HUU), caused by a genetic mutation in the SLC2A9 gene.

Clinical Signs of HUU

Dogs affected with HUU lack a protein which ...

Misconceptions About Canine Degenerative Myelopathy

Misconceptions About Canine Degenerative Myelopathy

If there is anything that I have learned in Paw Print Genetics’ quest to prevent canine inherited diseases, it is that degenerative myelopathy (DM) is one of the most misunderstood diseases in the dog breeding community. This late-onset, progressive neurological disease is notorious for cutting affected dog’s lives short and preventing them from living out their golden years. Unfortunately, sometimes there are misunderstandings in regard to what causes DM, what DM genetic test results mean, and whether or not DM occurs in certain breeds or bloodlines. I will attempt to address the confusing aspects of DM in order to empower people to eliminate this devastating disease from their blood lines.

How Do DM Affected Dogs Present? How is it Inherited?

Dogs affected with DM typically begin showing signs of painless, hind limb weakness and loss of balance around 7 to 10 years of age. These dogs often have difficulty rising after lying down, will drag their hind feet while walking, and abnormally cross their legs while standing. As the disease progresses, affected dogs’ front limbs also become progressively weaker until the dog becomes unable to walk. Affected dogs also may develop urinary and fecal incontinence as the disease progresses. Most ...

Preventing Inherited Ataxias and Primary Lens Luxation in the Parson Russell Terrier and Related Breeds

Preventing Inherited Ataxias and Primary Lens Luxation in the Parson Russell Terrier and Related Breeds

Previously known as the Jack Russell terrier, the Parson Russell terrier’s nearly 200 year long history began in the 1800’s when Parson John Russell of England obtained a terrier named Scout with the purpose of training him for European red fox hunting. Russell eventually developed a particularly adept line of terriers meant to run alongside hunters on horseback and dispatch foxes.

The name, Jack Russell Terrier was previously used to encompass dogs which are now recognized as three separate breeds in the U.S, the Jack Russell terrier, the Parson Russell terrier, and the Russell terrier. Despite their close genetic relationship and very similar appearance, leg length and body shape can be used to help differentiate the three breeds. Parson Russell terriers possess the longest legs and a square-shaped body while the other two breeds display shorter legs and a rectangular body shape. The Russell terrier is the shortest of the three varieties. Parson Russell terriers and Russell terriers are both recognized by the AKC, however the Jack Russell Terrier remains unrecognized by the organization and is bred primarily for its ability to hunt rather than for its conformational merits. Despite these physical differences, the three breeds share many genetic similarities ...

Preventing Hereditary Cataracts in the French Bulldog

Preventing Hereditary Cataracts in the French Bulldog

Though there are mysteries in regards to the early origins of the French bulldog, it is probable that this spunky breed is a 19th century product of breeding early English bulldogs and miniature bulldogs with other small breeds. As these smaller, English bred bulldogs became popular, many were either exported to France from England or accompanied their English owners to France in search of employment. At some point in the mid to late 1800’s, the small bulldogs were given the name “Bouledogue Français” and were recognized as their own unique breed. Early French bulldogs with either “rose ears” (ears folded at the tip) or pricked “bat ears” were common. However, with the spread of the breed to the United States, American dog fanciers created the first French bulldog breed standard describing the “bat ear” trait seen in modern Frenchies as the “correct” ear type.  In the process of establishing their modern appearance and perfecting the breed, like other purebred dogs, French bulldogs have developed some inherited diseases that concern Frenchie aficionados today. One such disease is a disorder known as hereditary cataracts (HC).

A cataract, in general, is the clouding of the lens of the eye. This cloudiness interferes ...