Tag Archives: University of Pennsylvania

A chicken-flavored electrolyte drink could help sniffer dogs stay hydrated

The first comparison of three common hydration methods for sniffer dogs shows that while all are effective, dogs drink more and are more hydrated when given a chicken-flavored electrolyte drink compared to plain water or when injected with electrolytes under the skin. The study, published in open-access journal Frontiers in Veterinary Science, also shows that the dogs did not suffer from a buildup of electrolytes from the drink, suggesting that electrolyte drinks are a safe hydration alternative for sniffer dogs, who are at risk of heat stroke in hot weather.

Working dogs, such as search and rescue dogs or police dogs, are crucial assistants when authorities respond to disasters or check for contraband at border crossings. These dogs often work in challenging environments, and can sometimes exert themselves to the point of exhaustion and heat stroke. In fact, hot weather can be dangerous for working dogs, as dogs don’t sweat much and rely on panting to cool themselves, meaning they can overheat easily.

detection dog

The risk of heat stroke increases with dehydration, so one effective way to help working dogs stay safe is to keep them hydrated. However, there are different ways to do this. “People use different techniques to hydrate working dogs,” says Cynthia Otto of the University of Pennsylvania, who was involved in the study. “Dog handlers disagree about the most effective method, and since there was no data on the safety or effectiveness of each technique, we wanted to provide some clarity.”

The classic hydration technique is to provide free access to plain drinking water. A second technique involves delivering water and electrolytes through a needle under the skin, which is known as subcutaneous hydration. Drinks containing electrolytes, such as sodium and potassium, are a third option, but these are controversial. Such drinks make sense as a rehydration aid for humans, as we lose electrolytes when we sweat. However dogs sweat very little, leading critics to say that the drinks could cause an unhealthy buildup of electrolytes in dogs.

The research team investigated these three common hydration strategies in a group of Border Patrol sniffer dogs who inspect vehicles at the Texas border, during the hot summer months. The team took a variety of measurements for each dog, including their hydration levels, fluid intake and work performance.

Happily, all three hydration strategies appear to be effective, and the dogs showed similar behavior, body temperature, and work performance regardless of the way they were hydrated. “In this controlled setting, all the hydration techniques were safe and effective,” says Otto.

However, dogs receiving a chicken-flavored electrolyte drink drank significantly more fluid and had greater hydration levels. Interestingly, these dogs did not suffer from a buildup of sodium, a component of electrolyte drinks that could have negative effects in the body in large quantities. The dogs who drank electrolytes excreted the sodium in their urine, meaning their blood levels remained normal. Overall, the dogs handled the electrolytes well, suggesting they are a safe and effective hydration method.

These results surprised the researchers, as a previous study had reported that dogs who were offered a non-flavored electrolyte drink, drank very little of it. The chicken flavoring may have been key, making the dogs think they were having a tasty treat, but the team will need to investigate this further.

“If a dog is reluctant to drink, then a highly palatable flavored electrolyte solution may give them a boost,” says Otto. “However, these are healthy dogs in a controlled environment, and we don’t know if all electrolyte or flavoring approaches are created equal, so we will need to do further work.”

Journal reference:  Cynthia M. Otto, Elizabeth Hare, Jess L. Nord, Shannon M. Palermo, Kathleen M. Kelsey, Tracy A. Darling, Kasey Schmidt, Destiny Coleman. Evaluation of Three Hydration Strategies in Detection Dogs Working in a Hot Environment. Frontiers in Veterinary Science, 2017; 4 DOI: 10.3389/fvets.2017.00174

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Changes in Skin “Microbiome” During Canine Atopic Dermatitis Could Lead to Antibiotic-Free Therapies

Atopic dermatitis (AD), a chronic inflammatory skin condition and the most common form of eczema, is estimated to afflict as much as 10 percent of the U.S. population, and is much more common now than it was 50 years ago. Veterinary clinical estimates also show that approximately 10 percent of dogs have atopic dermatitis.

How AD arises isn’t yet fully understood, but a study from researchers from the Perelman School of Medicine at the University of Pennsylvania and Penn’s School of Veterinary Medicine, have uncovered important insights about the association of AD in dogs compared to humans. The study appears online in the Journal of Investigative Dermatology.

atopy

To a greater extent than mouse models, canine AD shares important features of the human version. For example, in both humans and dogs AD has been linked to abnormal blooms of Staphyloccocus bacteria on the skin – mostly Staphyloccocus aureus in humans, and Staphyloccocus pseudintermedius in dogs.

In the study, the research team, comprised of veterinary dermatologists, microbiologists, pathologists, and primary scientists, tracked the bacterial populations, or “microbiomes,” on dogs’ skin, and key properties of the skin’s barrier function during an occurrence of AD, and again after standard treatment with antibiotics. During the flare, researchers observed a sharp decrease in the diversity of the skin bacterial population as certain bacterial species proliferated, along with a decrease in the skin’s protective barrier. With antibiotic therapy, both measures returned to normal levels.

“In both canine and human atopic dermatitis we hypothesize there is a similar relationship among skin barrier function, the immune system, and microbes, even if the individual microbe species aren’t identical,” said senior author Elizabeth A. Grice, PhD, an assistant professor of Dermatology and Microbiology at the Perelman School of Medicine at the University of Pennsylvania. “The hope is that insights gained from this study and others like it will enable us one day to treat this condition by altering the skin’s microbiome without antibiotics.”

Thirty-two dogs (15 with canine AD, and 17 without) from Penn Vet’s Ryan Hospital were enrolled in the study. On three occasions – first during AD flares in the affected dogs, then after 4-6 weeks of targeted antibiotics, and finally 4-6 weeks after treatment concluded – the team took swabs from several areas of skin on the affected dogs. They surveyed the microbiomes of these samples by amplifying and sequencing copies of a key bacterial gene whose DNA sequence is distinct for different bacterial species.

Samples from the dogs with ongoing AD had almost ten times the proportion of Staphylococcus species, compared to the control dogs. Corynebacterium species also rose, as they typically do in humans with AD. A standard measure of the diversity of the dogs’ skin microbiomes also decreased sharply, indicating that the abnormal bacterial proliferation – chiefly from S. pseudintermedius – had crowded out other, harmless or potentially beneficial bacterial species.

At the second visit, immediately following completion of antibiotic therapy, the abundance of Staphyloccocus and Corynebacterium on the skin of affected dogs and the diversity of their skin microbiome had returned almost to the levels seen in the control dogs. Those measures remained largely the same in the third visit, after antibiotic therapy was finished.

Impairment in the skin’s ability to work as a “barrier” to keep moisture in and harmful bacteria out is considered a possible factor in triggering or advancing AD. Under the guidance of Elizabeth Mauldin, DVM DACVP, DACVD, an associate professor of Dermatopathology in Penn’s School of Veterinary Medicine, the researchers also tested skin barrier function in the dogs at each of their three visits. Results showed that the low-bacterial-diversity state of AD flares – corresponding to lesions of AD on the skin – correlated with impairments in the skin barrier, as indicated by a standard test of the water loss rate through the skin (TEWL).

“We don’t know if the bacterial overgrowth is weakening the skin’s barrier function or a weakening of the barrier is enabling the bacterial overgrowth, but we do know now that they’re correlated, and that’s a novel finding,” Grice said.

The research team is now conducting further studies of the microbiome in canine atopic dermatitis, in particular to determine how antimicrobial therapy promotes bacterial resistance.

“This investigation is a prime example of the One Health approach to research, a recognition that we’re dealing with the same disease processes in animals and in humans,” said lead author Charles Bradley, VMD, DACVP, a lecturer and dermatopathologist of pathobiology in Penn’s School of Veterinary Medicine. “The findings highlight the importance of dogs as a model for human dermatitis and help lay the groundwork for new therapeutic strategies, for example involving microbiome transplants to compete with the harmful bacterial overgrowth, as an alternative to antibiotic therapy.”

Source:  University of Pennsylvania media release

Canine hereditary diseases more common than previously indicated

Comment from me (DoggyMom):  I am particularly pleased to read in this media release that the researchers are recommending cooperation between industry, science and laypersons.  As a canine massage therapist, I have found the traditional ‘evidence-based medicine’ fraternity reluctant to involve specialists in other fields and particularly those that are not research scientists or veterinarians.
It is my hope that we can cooperate more in the future as we undertake research into dog health and behavior because by sharing different points of view and expertise, we develop a richer range of options in problem-solving.
Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, The Balanced Dog, Christchurch, New Zealand

Genoscoper Ltd. has published in cooperation with the researchers of University of Helsinki and Pennsylvania (USA) the most comprehensive study on canine hereditary disorders so far. The research brings new information about genetic disorders causing diseases in different dog breeds. The results can be utilized both in dog breeding and veterinary diagnostics. The study was published on PLOS ONE on 15 August 2016.
Dogs have more hereditary diseases than previously thought

Dogs have more hereditary diseases than previously thought. Photo: Eeva Karmitsa

– We noted that surprisingly many canine inherited disorders are actually more widespread than indicated by their original discovery studies, which opens up the door for several future scientific investigations, explains senior author Dr. Hannes Lohi from the University of Helsinki canine genetics research group.

– The technological potential to test a dog for multiple inherited disorders at once has existed for several years. The challenge is to harness that potential for practical use in improved veterinary disease diagnostics, sustainable breeding selections, personalized pet care, and canine genetics research, says lead author Dr. Jonas Donner of Genoscoper Laboratories. Genoscoper Ltd. is a Finnish company specialized in animal genetics and gene testing.

By testing nearly 7000 dogs representing around 230 different breeds for predisposition to almost 100 genetic disorders, the research team observed that 1 in 6 dogs carried at least one of the tested disease predisposing genetic variants in their genome. Moreover, 1 in 6 of the tested genetic variants was also discovered in a dog breed in which it had not previously been reported in the scientific literature. Through clinical follow up of dogs genetically at risk, the research team was able to confirm that several disorders cause the same disease signs also in other than previously described breeds.

– Precisely as we humans, every dog is likely to carry genetic predisposition for some inherited disorder, so we expect these numbers to grow as the numbers of tested disease variants, breeds, and dogs further increase, confirms Dr. Donner.

Co­oper­a­tion is key to health­ier dogs

– Our study demonstrates the importance of collaboration between different contributors – academics, industry and dog fanciers – to reach novel resources that not only enable better understanding of canine genetic health across breeds but also provides viable solutions to improve the health.  The published study provides also an excellent example of the added value of research collaborations between academia and industry in a form that leads to a powerful innovation that start changing the everyday practice in veterinary medicine and improves the welfare of our dogs, says Lohi.

Ge­netic panel screen­ing de­liv­ers res­ults

The study concludes that comprehensive screening for canine inherited disorders represents an efficient and powerful diagnostic and research discovery tool that has a range of applications in veterinary care, disease research, and dog breeding. The authors emphasize that availability of complex DNA-based information is important progress for improvement of the health of purebred dogs, but it should be utilized in combination with other established approaches that promote sustainable breeding and benefit breed health.

The full scientific publication can be accessed here.

Reference:
Donner J, Kaukonen M, Anderson H, Möller F, Kyöstilä K, Sankari S, Hytönen MK, Giger U and Lohi H. Genetic panel screening of nearly 100 mutations reveals new insights into the breed distribution of risk variants for canine hereditary disorders. PlosONE, 1(8): e0161005. doi:10.1371/journal.pone.0161005, 2016.

Source:  University of Helsinki media release

The underlying cause of canine diabetes

In a new effort, researchers from the University of Pennsylvania and Baylor College of Medicine have used advanced imaging technology to fill in details about the underlying cause of canine diabetes, which until now has been little understood. For the first time, they’ve precisely quantified the dramatic loss of insulin-producing beta cells in dogs with the disease and compared it to the loss observed in people with type 1 diabetes.

Diabetic dogs had a sharp loss of insulin-producing beta cells compared to non-diabetic dogs

Diabetic dogs had a sharp loss of insulin-producing beta cells compared to non-diabetic dogs

“The architecture of the canine pancreas has never been studied in the detail that we have done in this paper,” said Rebecka Hess, professor of internal medicine at Penn’s School of Veterinary Medicine and an author on the study.

Despite important differences between the disease in dogs and humans, the study also identified key similarities that suggest investigating diabetes in dogs may yield valuable insights into treating humans.

The research was led by Emily Shields, currently a graduate student in Penn’s Perelman School of Medicine, who completed much of the work as a high school and then college student in labs at Penn and Baylor.

The study was published in PLOS ONE.

Canine diabetes can be managed with insulin, similar to type 1 diabetes in humans. But, unlike the human version of the disease, dogs typically develop diabetes in middle or old age, while people with type 1 diabetes are typically diagnosed during childhood. In addition, while type 1 diabetes is known to be an autoimmune condition, researchers haven’t found conclusive evidence that the same is true in dogs.

To learn more about the factors that contribute to canine diabetes, the researchers made use of a repository of donated tissue samples from dogs — 23 with diabetes and 17 without — who had been treated at Penn Vet’s Ryan Hospital.

The team used robotic microscopes that can rapidly move around a slide taking images of pancreas tissue samples, which were analyzed by computer to determine the contents.

“In a larger view we could look at the entire cross-section of pancreas to determine how many islets there were and how big they were,” Shields said. “Then we could zoom in to differentiate beta cells, which produce insulin, from alpha cells, which produce glucagon.”

They found that beta cells dropped off in dramatic fashion in diabetic dogs, reduced 13-fold compared to non-diabetic animals. They also found that non-diabetic canine islets contained a large percentage of beta cells, comprising about 80 percent of endocrine cells. In contrast, beta cells comprise slightly more than 50 percent of endocrine cells in non-diabetic human islets. The researchers noted that this may mean that dogs need to lose more beta cells before experiencing symptoms of diabetes. The observation could explain why dogs develop a form of diabetes that is similar to type 1 diabetes, but do so later in life, compared to humans.

They also identified features of the islets and pancreatic structures that were different in dogs than in humans.

“In sharp contrast to human diabetes, in which there are a lot of islets still present but none contains insulin, we found in dogs that only a few beta cells were present and the islets were incredibly small,” Kushner said.

While the researchers had hoped to be able to visualize immune cells infiltrating the pancreas and attacking beta cells, they failed to do so.  While other signs point to canine diabetes being an autoimmune condition, this study did not find a “smoking gun.”

Though the work highlights differences between canine and human diabetes, it also points to a number of similarities that distinguish the two from diabetes in rodents, which are often used as models to study the disease.

For example, the scientists observed that dogs’ beta cells were distributed throughout the islets, as beta cells in humans are. In rodents, beta cells are concentrated in the center of the islet.

“Now that we know more about the disease in dogs and in particular how they are similar to humans in ways that rodents are not, it makes them more appealing as a model,” Kushner said.

At Penn, Hess is currently working to look for genetic markers in dogs that heighten a dog’s risk of developing diabetes.

“My hope is that with genetic screening we can eventually identify pre-clinical diabetic dogs, potentially making breeding recommendations that could decrease the incidence and prevalence of the disease in dogs,” Hess said.

Source:  Penn News media release

Hear bark or C-Barq?

I’ve just signed Izzy up so we can complete a C-Barq questionnaire for her.

I know what you are thinking:  you don’t ‘see’ barks, you hear them.  Well actually, C-Barq stands for ‘Canine Behavioral Assessment and Research Questionnaire’ and it’s another example of citizen – or participatory – science.

Created by Dr. James Serpell who is a behaviorist at the Center for the Interaction of Animals and Society (CIAS) in Pennsylvania, the questionnaire is designed to provide dog owners and professionals with standardized evaluations of temperament and behavior.    The Center is based within the School of Veterinary Medicine at the University of Pennsylvania.

Penn University medicine

Tested extensively for reliability and validity on large samples of dogs of many breeds,  the current version consists of 101 questions describing the different ways in which dogs typically respond to common events, situations, and stimuli in their environment. It should take about 15 minutes to complete (I haven’t done this yet).

Please pay attention, however, to the sign-in page where questions are asked about your dog’s breed, background, and behavior.  This helps in coding the answers for analysis.

So far, over 80,000 dogs have been included in the study. Dr Serpell says, “There is no other breed or species of animal with such a wide variety of appearance and behavior.”

Between 10 percent and 15 percent of dogs can show very high levels of aggression, Serpell says, while 20 or 30 percent show no aggression.

Pit bulls and Akitas, popular breeds for fighting and guard dog duty, show serious aggression toward other dogs. But the title for most aggressive overall actually goes to tiny dachshunds, which display heightened aggression toward dogs, strangers and even their owners.

Source:  Science Friday on pri.org

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, Canine Catering Ltd, Christchurch, New Zealand

A vaccine for canine osteosarcoma?

Osteosarcoma is a highly aggressive bone tumor that affects at least 10,000 dogs annually in the United States, alone.

Photo by osteosarcomaindogs.org

Photo by osteosarcomaindogs.org

It is estimated that 90-95 percent of canine osteosarcoma subjects have microscopic metastatic disease (spread of cancer cells to other parts of the body at the time of diagnosis). Standard of care includes removal of the primary tumor—usually by amputation—followed by chemotherapy. Systemic chemotherapy given after amputation delays the development of metastatic disease; however, despite treatment, most dogs die of the disease within one year of diagnosis.

A new option may be available in the future if Dr. Nicola Mason’s research at the University of Pennsylvania School of Veterinary Medicine produces satisfactory results. Mason, an assistant professor of medicine and a Board-certified ACVIM Diplomate in Small Animal Internal Medicine, is evaluating the first vaccine for canine osteosarcoma.

The approach harnesses the power of the dog’s immune system, “training” it to seek out and destroy cancer cells that remain after amputation and chemotherapy.

Over a century ago, an orthopedic surgeon named William Coley recognized that human sarcoma patients with concurrent bacterial infections that caused high fevers had improved overall survival times compared to those sarcoma patients without infection. This led him to develop a therapeutic concoction of live bacteria that he injected into patients with bone sarcomas. He documented improved survival and in some cases, complete remission in individuals with the aggressive disease by using this early form of “immune therapy.”

Mason’s team is employing similar immune therapeutic strategy to treat dogs with osteosarcoma that have undergone the standard of care treatment (amputation and chemotherapy) to prevent metastatic disease. “The concept is that administration of the Listeria-based (genetically modified bacteria) vaccine will activate the patient’s immune system and educate it to recognize cells that express the target molecule,” says Mason.

Dogs are given the live bacterial vaccine intravenously, Mason explains, and it induces a mild transient fever on the day of vaccination. The dogs are usually treated as outpatients and return home the same day. “We have found highly encouraging results when the vaccine is given to patients that have no evidence of metastatic disease at the time of the study enrollment, which is three weeks after the last chemotherapy is administered. Four out of the first five dogs vaccinated are alive at least two years after their initial diagnosis, which is more than twice their expected survival duration. The vaccine has not yet shown any serious short- or long-term side effects, either.”

Mason says the results have led researchers to evaluate whether this vaccine may be able to directly target and kill the bone tumor itself, perhaps eliminating the need for amputation in the future.

Source:  American College of Veterinary Internal Medicine media release

Behavioural problems in pet store dogs

Dogs purchased from pet stores are more likely to have a range of behavior problems than those purchased from small, non-commercial breeders, says a study by researchers at the Best Friends Animal Society and the University of Pennsylvania School of Veterinary Medicine.

The study was published in the Journal of the American Veterinary Medical Association.

The study involved 413 dogs purchased from pet stores.  Psychological and behavioral characteristics of these dogs were compared to the same characteristics in 5,657 dogs obtained from small-scale, private breeders.  (Most puppies sold in pet stores in the USA are sourced from large-scale, puppy mill type commercial breeders).

Results show that dogs obtained as puppies from pet stores showed significantly more aggression toward human family members, unfamiliar people and other dogs. Dogs purchased from pet stores were almost twice as likely to exhibit aggression directed toward unfamiliar dogs than dogs purchased from small non-commercial breeders.

The pet store dogs also a displayed greater fear of other dogs and typical events in pet dogs’ lives, had more behavior problems when left alone at home, and experienced more problems with house-soiling.  These behaviors in young adult dogs are reasons typically cited by people who surrender their pets to animal shelters.

“The results were so one-sided that in the wide range of behavior problems we included in our analysis, pet store dogs failed in every single case to even obtain one more favorable score than the comparison group of dogs” says Dr Frank McMillan of Best Friends Animal Society.

The research team acknowledges that the exact causes of the behavioral problems observed are not known; until these causes are understood, they recommend avoiding purchasing puppies from pet stores.

Source:  BusinessWire media release

See my related post about the ASPCA’s No Pet Store Puppies initiative