Tag Archives: doberman pinschers

Canine compulsive disorder genetics

Research led by investigators in veterinary and human medicine has identified genetic pathways that exacerbate severity of canine compulsive disorder in Doberman Pinschers, a discovery that could lead to better therapies for obsessive compulsive disorder (OCD) in people.  The discovery appears in the International Journal of Applied Research in Veterinary Medicine.

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A Doberman pinscher flank sucking, an example of canine compulsive behavior

“Dogs naturally suffer complex diseases, including mental disorders that are similar to those in humans. Among those is canine compulsive disorder (CCD), the counterpart to human obsessive compulsive disorder (OCD),” says the study’s first and corresponding author Nicholas Dodman, BVMS, DACVA, DACVB, professor in clinical sciences and section head and program director of animal behavior at Cummings School of Veterinary Medicine at Tufts University.

OCD is one of the world’s most common neuropsychiatric disorders, affecting an estimated 1 to 3 percent of people and listed by the World Health Organization as among the 20 most disabling diseases. OCD is often characterized by distressing thoughts and time-consuming, repetitive behaviors, while canine compulsions may include repetitive tail chasing, excessive grooming and flank and blanket sucking. Current OCD therapies are not as effective as they could be; medicinal treatment benefits only about half of all human patients.

No previously recorded study in humans or dogs has addressed the factors that drive severity in OCD and CCD.

“Genomic research on human neuropsychiatric disorders can be challenging due to the genetic heterogeneity of disease in humans,” says neurologist Edward Ginns, MD, PhD, professor of psychiatry, neurology, pediatrics and clinical pathology, and director, program in medical genetics at the University of Massachusetts Medical School and a co-author on the new study. “Canine compulsive disorder shares behavioral hallmarks, pharmacological responsiveness, and brain structural homology with human OCD, and thus is expected to be an important animal model.”

The research team compared whole genome sequencing of 70 Doberman pinschers to search for inherited factors that exacerbate CCD. Researchers identified two loci on chromosomes that were strongly correlated with severe CCD, as well as a third locus that showed evidence of association.

The locus most strongly associated with severe CCD was found on chromosome 34 – a region containing three serotonin receptor genes.

“This is particularly significant because drugs that work on the serotonin system are the mainstay treatment for OCD in humans, which demonstrates further correlation between the human and animal models,” says Dodman.

The second locus significantly correlated with severe CCD was on chromosome 11, the same chromosome that contains a gene thought to increase the risk of schizophrenia in humans. This discovery, along with suggestive evidence found on chromosome 16 linking CCD to stress tolerance, may also be relevant to the pathophysiology of OCD, according to the study authors. “Comparative genomics is a particularly attractive approach to reveal the molecular underpinnings of disease in inbred animals with the hope of gaining new insights into these diseases in dogs and humans,” says Ginns.

“If the canine construct is fully accepted by other OCD researchers, this spontaneously-occurring model of the condition in humans, right down to the biological pathways involved, could help point the way to novel and more effective treatments for such a debilitating condition,” Dodman says.

Source:  Tufts Now media release

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Treating heart disorders in dogs

A novel therapy tested by University of Guelph scientists for treating a fatal heart disorder in dogs might ultimately help in diagnosing and treating heart disease in humans.

Ontario Veterinary College (OVC) professors Glen Pyle and Lynne O’Sullivan have also identified potential causes of inherited dilated cardiomyopathy (DCM) or “weak heart.”

The groundbreaking study was published this month in the American Journal of Physiology.

Cardiology exam

“The cardiovascular systems of dogs and people are very similar,” said Pyle, a professor in OVC’s Department of Biomedical Sciences and a member of U of G’s Centre for Cardiovascular Investigations.

“It allows us to do comparative investigations that can advance understanding of this fatal condition.”

In both dogs and people with DCM, the weakened heart muscle becomes unable to pump blood around the body. The cause of the problem is often unknown, although it’s common to involve genetics.

Researchers suspect malfunctioning muscle proteins cause the heart to weaken, allowing it to dilate like an overfilled balloon.

DCM is the second leading cause of heart failure in dogs, and it’s especially common in large breeds. Dogs typically show no symptoms until the disease is well-advanced.

The condition is often inherited; up to 60 per cent of Doberman Pinschers are affected during their lifetime.  Other breeds such as Irish wolfhounds and Great Danes also have high rates.

In people, 30 to 50 per cent of DCM cases are hereditary.

The end result of DCM is congestive heart failure. While medical advances have reduced deaths from congestive heart failure by 40 per cent in the past decade, the condition still afflicts hundreds of thousands of Canadians, and the five-year mortality rate remains high.

Aging populations worldwide are likely to cause dramatic increases in the rate of heart failure in the upcoming decades, Pyle said.

“The cause of a substantial percentage of DCM cases remains unknown,” he said.  “This is why it’s urgent to develop novel agents that can improve heart function.”

For the study, Pyle and O’Sullivan, a clinical cardiologist in OVC’s Health Sciences Centre, worked with researchers at the University of Washington to test a novel therapy in diseased heart cells.

 The therapy involves introducing a molecule involved in muscle contraction. In heart cells from dogs with DCM, it restored normal function. The next step is developing a gene therapy that would allow the molecule to be produced in heart muscle cells in patients with DCM.

“This suggests it’s a promising therapeutic approach worth further investigating for the treatment of DCM,” said O’Sullivan. One of 10 board-certified veterinary cardiologists in Canada, she runs OVC’s Doberman DCM screening program.

The researchers also discovered some problems in the heart muscle that likely contribute to DCM.  “This may shed light on the mechanical impairment in failing hearts,” Pyle said.

The Guelph scientists are also working with researchers in Finland on DCM genetics and proteins. That work might lead to development of therapies for targeting specific proteins, said Pyle.

Both researchers belong to U of G’s Centre for Cardiovascular Investigations, one of a few centres worldwide studying heart disease from single molecules to clinical applications.

Source:  University of Guelph media release

Albino Dobermans

Michigan State University researchers have identified a genetic mutation in Doberman pinschers that causes albinism in the breed, a discovery that has eluded veterinarians and breeders worldwide up until now.

Michigan State University photo

Michigan State University photo

Paige Winkler, a doctoral student at the College of Veterinary Medicine, says that the researchers found a gene mutation that results in a missing protein responsible for the pigmentation of cells.

Albino Dobermans possess a pink nose, white or very light colored coats, and pale irises in the eyes.  These characteristics are similar to human albinos who have light skin, eye discoloration and often experience visual problems.

Like human albinos, the albino Dobermans are sensitive to light and have an increased risk of skin tumors.

Winkler says that this discovery will help Doberman breeders in the future where breeding lines carrying the defective gene can be identified.

Source:  Michigan State University media statement

OCD – dogs and humans are not that different

The structural abnormalities in the brains of dogs suffering from canine compulsive disorder (CCD) are similar to the abnormalities found in humans suffering from obsessive compulsive disorder (OCD) according to new research.

A collaboration between veterinarians at the Cummings School of Veterinary Medicine at Tufts University and researchers at the McLean Imaging Center at McLean Hospital, in Belmont, Massachusetts have published their findings in Progress in Neuro-Psychopharmacology & Biological Psychiatry.

The study involved 16 Doberman Pinschers, 8 with CCD and 8 without.  Dogs with CCD engage in repetitious and destructive behaviors such as flank- and blanket-sucking, tail chasing, and chewing,  whereas people with OCD tend to have repetitious behaviors that interfere with their daily life.

Here’s a video of a German Shepherd with CCD engaging in a circling behavior:

“While the study sample was small and further research is needed, the results further validate that dogs with CCD can provide insight and understanding into anxiety disorders that affect people.  Dogs exhibit the same behavioral characteristics, respond to the same medication, have a genetic basis to the disorder, and we now know have the same structural brain abnormalities as people with OCD,” said Nicholas Dodman, BVMS, DACVB, professor of clinical sciences at the Cummings School of Veterinary Medicine at Tufts University.

It should be noted that the research also provides insight into dog behavior and management.  In some cases, a dog labelled as ‘bad’ or ‘destructive’ may actually have a biological basis for their problems.

Source:  TuftsNow media release

Dog-friendly Las Vegas

The Riviera Hotel and Casino in Las Vegas is pet-friendly.  Through discount site Coupaw, it is currently offering a 3-day/2-night stay for 2 adults at the Riviera Hotel and Casino in Las Vegas for $30.  The voucher for this deal includes a Las Vegas BITE card which provides the cardholder with other excellent deals on a wide array of food and entertainment throughout Las Vegas.

Riviera Hotel

As with many pet-friendly hotels, there are restrictions including breed specific ones 😦

The fine print says:

2 Dog maximum – $25 additional fee – per dog/per night. Pet fees are paid directly to the Riviera Hotel. All pet arrangements must be made directly with the Riviera Hotel. Pet friendly rooms are located in classic room types – San Remo tower. Dogs cannot exceed 50 lbs. Dog Owner must provide proof of current vaccinations including exhibiting current rabies tag on check in. Dogs that are excluded to stay in pet friendly rooms include but are not limited to: Akitas, Alaskan Malamutes, Chows, Doberman Pinschers, English Bull, Terriers, German Shepherds, Mastiffs, Pit Bulls, Presa, Canaries, Rottweiler, or any dog with a bite history. Coupaw is not responsible for the Riviera hotel refusing to accommodate specific dogs for any reason.