When a beloved pet gets sick, it’s only natural to ask what caused their illness. Unfortunately, we don’t always know the answer.
Canine dysautonomia (CD) is a devastating condition that disrupts autonomic functions, such as digestion and heart rate. The disease has a high fatality rate, and its cause is unknown. In the U.S., a few hundred dogs a year suffer from CD.
Maedeh Rafiee, who earned her doctorate in veterinary science from Islamic Azad University in Tehran, Iran, returned to academia to study CD as a graduate student at UW. “Owners lose their pets because of canine dysautonomia,” says Rafiee. “I felt it was my responsibility to contribute to solving this problem.”
Rafiee is a member of Jonathan Fox’s veterinary science lab. Rafiee and other members of Fox’s lab are working with a veterinarian at Kansas State University to uncover CD’s cause, with the goal of eventually preventing the disease.
Defeating the autopilot
CD attacks the body’s “autopilot,” or autonomic nervous system, which regulates vital processes like digestion, swallowing, heart rate, and bladder control.
CD is a neurodegenerative disease. It kills neurons, and those neurons, once destroyed, don’t grow back. Though it’s possible for dogs to survive CD, survivors often have permanent issues like incontinence or digestive problems.
Most pet owners first notice CD due to gastrointestinal symptoms. The autonomic nervous system, damaged by CD, can’t effectively regulate normal intestinal movements. This can cause symptoms like vomiting, diarrhea, and loss of appetite.
A needle in a haystack
Dogs are much more likely to contract CD in certain geographic regions. In the U.S., the disease is present in the Midwest, extending into eastern Wyoming and eastern Colorado. This regional distribution implies that the disease is related to an environmental factor, rather than being passed from animal to animal.
Previous research on CD suggests that rural dogs that spend time significant time outdoors are at increased risk. Researchers believe the cause may be something in the soil. Many dogs ingest some soil while they’re digging—and perhaps ingest whatever causes CD as well.
Rafiee suspects a soil-dwelling microbe that produces some kind of neurotoxin may cause CD. But there are thousands of soil-dwelling microbes—and the researchers would also need to identify microbes that can produce neurotoxins.
To accomplish this difficult task, Rafiee and her colleagues collected samples of fecal matter from dogs with dysautonomia and dogs without dysautonomia. They grew, or “cultured,” microbes from each of the samples to attempt to find soil microbes that are present in sick dogs, but absent in healthy dogs.
Rafiee and her colleagues identified some soil bacteria that were present in the fecal matter of dogs with dysautonomia that so far do not appear to be present in the fecal matter of healthy dogs. The research team is now conducting follow-up studies to try to pin down whether these bacteria produce neurotoxins—and perhaps cause CD.
Creating new treatments
If Rafiee and her colleagues find the cause of CD, they could develop ways to prevent CD and diagnose it earlier. Scientists might even be able to create a vaccine that could be used in high-risk areas.
Though CD is a rare disease, those impacted by canine dysautonomia want to understand and find new treatments for it. Through UW’s last Giving Day campaign, Fox’s lab received significant contributions from grassroots donors in support of this research1. During this year’s Giving Day on Thursday, October 23, Fox hopes to raise additional funds in order to continue researching this elusive disease.
“We’re in the 21st century. It’s really unusual to have a disease we have so little understanding of despite all the effort,” Fox comments. “But there’s been so many advances in research methods and disease diagnostics. We think it should be possible to figure out this disease soon.”
Figuring out the cause of CD could have implications beyond dogs. Other animals, including rabbits, cats, and horses, suffer from dysautonomia. Understanding the disease in dogs could help researchers understand dysautonomia in these species as well.
This article was originally published in the 2025 issue of Reflections, the annual research magazine published by the UW College of Agriculture, Life Sciences and Natural Resources.
1. This research is also supported by a grant from the American Kennel Club.
