It is a long-held belief that the symptoms of equine asthma (recurrent airway obstruction, heaves, chronic obstructive pulmonary disease) worsen in the winter when horses are kept indoors, exposed to dust and other airborne irritants, for longer periods.

Dr. Jean-Pierre Lavoie, of the Universite de Montreal, reports that this is not the case. "Unlike commonly believed," he said, "horses with heaves have worsening of their clinical signs and airway obstruction when it is hot and humid during the summer."

The study included 14 asthmatic horses. Barn temperature and relative humidity values were obtained and air enthalpy (the amount of heat in the air) was calculated. Correlation tests were used to study the relationship between the mean daily clinical scores of horses and environmental variables. Lung function parameters were recorded and compared at four-day intervals during hot (25°C) and warnV(18°C) barn conditions.

Dr. Lavoie also found a correlation between increased symptoms and high pollen counts, affecting air quality, in the summer.

As a result, it recommended that owners provide asthmatic horses with a temperate environment, especially during periods when the disease is exacerbated and exposure to irritants can't be avoided.

Summer may be harder on equine

asthma suffers that we thought. A new

study shows that symptoms actually



Equine metabolic syndrome (EMS) is often compared to type-2 diabetes in humans because both diseases are characterized by obesity and insulin resistance. Another common clinical sign of EMS is laminitis, which significantly affects a horse's well-being and performance.

There are no standardized tests in place for EMS, making it very difficult to diagnose the disease. Veterinarians sometimes test for blood insulin and glucose levels, but these results are often skewed by the horse's metabolic state or stress. For these reasons, EMS is often misdiagnosed. Practitioners usually base a tentative diagnosis of EMS on a horse's physical appearance or its history of laminitis.

A team of researchers at the University of Saskatchewan is investigating whether two biomarkers of human type-2 diabetes may aid in the early detection of EMS in horses. In this study, they will test for high levels of the two biomarkers - methylgyoxal (MG) and d-lactate - in blood samples of healthy horses and those that are overweight and experiencing an episode of laminitis.

If the team's findings show differences in one or both of the biomarkers between healthy and EMS-positive horses, their research could eventually lead to a more accurate and early diagnosis of EMS.

In another study - the first of its kind - researchers at Gluck Equine Research Center at the University of Kentucky and the University of Guelph have collaborated to find out if there are changes in the intestinal microbiota of horses afflicted with EMS. It is known that humans with metabolic disorders have these changes, so the researchers set out to compare 10 horses with EMS to 10 non-EMS controls.

Horses were of comparable age and fed a similar all-forage diet for at least two months before sampling. Fecal samples from all 20 horses were used to extract DNA for next generation sequence-based analysis of the bacterial microbiota in order to learn more about the populations.

Dr. Scott Weese, researcher at the Ontario Veterinary College said, "The study revealed a decrease in the fecal microbial diversity for the EMS horses as well as differences in the overall community structure when compared to the metabolically normal control group of horses."

Links have been made between obesity and lower microbial diversity in human,

[Overweight horses are at a higher risk of

developing health issues such as Equine]

dog and horse studies, but there is still much to learn about optimal values for diversity. With more research toward understanding the changes in microbiota and what influences these changes, it is possible this technology will be used in the future to help in management of syndromes such as EMS.


While there has been much research into gastric ulcers in Thoroughbred and Standardbred race horses across North America, Dr. Sarah Pedersen is the first to look at the prevalence of digestive tract disturbances in North American show jumping horses.

Dr. Pedersen, a veterinarian who graduated from the University of Calgary Faculty of Veterinary Medicine, is doing a Performance Horse Health Fellowship at TD Equine Veterinary Group in Calgary.

"What Sarah is researching is a common problem that clinicians regularly encounter in performance horses," said Dr. Dan French, of TD Equine. "What she's investigating in her project helps clinicians decide how we manage and treat sport horses."

Dr. Pedersen performed gastroscopies on 89 Warmblood show jumping horses, from 14 different barns, to understand the prevalence of two types of ulcers -squamous in the top part of the stomach and glandular in the bottom.

When a horse has an ulcer, it may show a lot of "non-specific" signs, including a decrease in performance. "Sometimes their hair coat won't look very good, they're struggling to keep weight on, they're sensitive when brushed," said Dr. Pedersen. "Another concern could be a change of barn or change of environment. Some horses get really stressed when they travel to competitions. All of those can be warning signs."

The only sure way to know whether your horse has ulcers is to have a veterinarian perform a gastroscopy. But owners don't always want to do that because they must fast their horse for a minimum of 12 hours, which can be a problem for an actively competing equine athlete.

"We wanted to give people a number, a percentage of horses that may or may not be suffering from ulcers in the barn, because some people may choose to give either a preventative dose of medication or treatment trial with medication to see if helps their horse," said Dr. Pedersen. "We wanted people to have some numbers to make that decision."

Results found 72 per cent of the horses had glandular ulcers - half of those were serious - and 40 per cent had squamous ulcers. A third of the horses had both squamous and glandular ulcers. The horses were at higher risk for ulcers if they exercised six or seven days a week and received hay only once per day.

"We're wondering if either there's a genetic component or if there's actually something to do with the job the horse does and the type of exercise," said Dr. Pedersen. "We're trying to answer that question in the lab now."

~ Jennifer  Allford

eman is the first dean of a Canadian veterinary college to serve as president of the Association of A


Skin wounds on horses are common and can take a long time to heal. A telephone survey of Saskatchewan veterinarians estimates that 23 per cent of all equine calls are wound-related. As such, a team of researchers from the Western College of Veterinary Medicine are studying ways to accelerate wound healing.

In comparison to ponies, it has been found that horses' wounds heal slower and often with complications. It is believed ponies' wounds heal more rapidly because they have a more exaggerated inflammatory response shortly after injury, which then quickly subsides.

Researchers have observed a similar inflammatory response in laboratory animals that is partially controlled by several cell proteins (beta arrestin-2, CXCL8 and CXCL10) and protein receptors (CXCR2 and CXCR3). By modifying these proteins in lab animals, scientists have been able to alter the speed of wound healing.

So far, no one has ever investigated whether these same proteins can be found in equine wounds. In this study, the researchers will examine skin biopsies taken from equine wounds and look for the genetic code of these same proteins.

If the proteins are present in equine wounds, they will measure how the levels of proteins change as the wound heals. They will also measure the difference in healing time between wounds on equine limbs and those on the thorax. Findings from this project may also lead to further studies evaluating the proteins' role in the healing differences between horses' wounds and ponies' wounds - and how scientists can potentially enhance the rate of healing J by influencing the proteins in the wound.









A new horse-centred program for people with early stage dementia, and their caregivers, has launched at UC Davis School of Veterinary Medicine, in California.

Last spring, as a trial run for the developing program, Stanford University and the non-profit group Connected Horse collaborated on the Equine Guided Support pilot study. It included 10 participants with dementia and their caregivers, who took part in three sessions working with horses on the ground - interacting, grooming and leading. According to Connected Horse's research abstract, facilitators "measured the effectiveness of equine-guided workshops on stress reduction and quality of life indicators for people with early stage dementia and their care partners."

The results were promising, showing a decrease in stress and undesirable behaviours in those with dementia, as well as an increase in positive communication with their caregivers and "awareness of individual abilities to adapt to changes in roles."

Following the success of the study, Connected Horse is now offering programs in partnership with UC Davis School of Medicine's Alzheimer's Disease Center. To learn more, visit

The results of a pilot study into the effects of Equine Assisted Learning (EAL) and Equine Assisted Psychotherapy (EAP) on adults and youth with mental health and addiction issues show that interacting with horses has positive benefits.

The 2014 study, led by Canadian researchers Dr. Colleen Dell, of the University of Saskatchewan, and Dr. Darlene Chalmers, of the University of Regina, evaluated the responses of 287 individuals from four programs in Saskatchewan after completing equine assisted sessions. Program facilitators also provided feedback on their impressions of the participants' experiences.

Two of the programs involved therapeutic horsemanship for First Nations children and youth in residential care; one focussed on self-development skills; and one involved Equine Assisted Psychotherapy, in which a licensed therapist joined a horse professional to help clients move forward with their therapy goals.

Following their sessions, participants filled out questionnaires which allowed them to summarize their feelings subjectively in response to open-ended questions, and to rate different aspects of the experience on a scale of 1-5.

The findings of the study suggest that the majority of the participants found working with horses to be helpful in understanding themselves, and reported feeling calmer and more in control of their feelings after learning from their interactions. Many also said they felt supported and comforted by the horses.

Further, the findings show that there is need to continue to develop equine assisted programs, understanding that there are significant variations in how this type of learning is applied across programs. As such, further exploratory research and evaluation studies are required, including following up with participants in the future to learn whether new coping skills and positive changes have been maintained. Next, Drs. Dell and Chalmers would like to undertake future research with a larger sample arid, ideally, conduct a randomized control trial.


Canadian Horse Annual 2017