Researchers from the Texas A&M College of Veterinary Medicine and Biomedical Sciences (VMBS) and Center for Systems Neuroscience in Hannover, Germany have discovered that fecal microbiota transplants (FMT) can reduce negative mental health symptoms in dogs with epilepsy—especially in dogs with a version of epilepsy that is resistant to drugs.

The work is published in the journal Frontiers in Veterinary Science.

FMT is a non-invasive treatment delivered via enema that has become popular in human medicine over the last two decades thanks to increased scientific understanding of the gut microbiome—the community of bacteria living in the gut that helps regulate healthy digestion.

Scientists have also discovered evidence that the gut microbiome may play an even bigger role, influencing other parts of the body—including the brain in what is called the gut-brain axis. Veterinary science experts have also begun studying this relationship with regards to animal health.

In their recent study, the researchers treated nine dogs with drug-resistant epilepsy—a type of epilepsy that does not respond to the usual drug therapies and affects approximately two-thirds of dogs with epilepsy. According to the study, dogs with this version of the disease tend to experience more ADHD- and anxiety-type symptoms than other dogs with epilepsy.

“Each patient in the study received FMT three times over a period of several weeks, and was monitored during follow-up appointments,” said Dr. Jan Suchodolski, the associate director of research and head of microbiome sciences at the Texas A&M Gastrointestinal Laboratory. “After treatment, each of the nine dogs showed significant improvements to their mental health, including a reduction of anxiety-like behavior and improved quality of life.

“While we don’t yet understand the mechanism causing these behavioral improvements, we hope to continue developing new ways to help patients with drug-resistant diseases using microbiome science,” he said. “Research in this field is highly translational, meaning it is helpful to both human and veterinary medicine.”

The gut and the brain

It may seem counterintuitive to try treating mental health symptoms using gut health, but all the evidence points toward a mysterious connection between these two bodily symptoms.

“The gut has a far more central role in overall health than most people realize,” Suchodolski said. “We talk about the gut-brain axis, but there is also the gut-kidney axis, the gut-liver axis, and others.”

The relationship between the gut and other body systems isn’t well understood yet, but scientists are steadily gathering more information.

“We know that situations with high levels of mental stress can affect gut motility,” Suchodolski said. “There are also several neurological diseases—including Alzheimer’s disease and strokes—that also seem to cause gut symptoms in patients, and vice versa. There have also been studies showing that changing the gut’s microbiome with probiotics or diet alterations can also affect disease symptoms, so there’s a lot of evidence of this relationship.”

FMT is just one kind of treatment that makes use of the gut-brain relationship, and it’s proving to be highly effective.

“If you think of the microbiome like a garden, FMT is like putting in a whole new ecosystem,” Suchodolski said. “You’re adding in all kinds of bacteria and other organisms to see if something changes.

“What’s most interesting is that our research team measured the seizure frequency in the patients after the treatment, and that improvement was not very strong. The behavior change was much more pronounced,” he said.

For the first time in nearly a decade, scientists have recorded an increased presence of young Maugean skates—a ray of hope for the survival of the endangered species.

The research by the University of Tasmania’s Institute for Marine and Antarctic Studies offers a promising sign for the Maugean skate, a species endemic to the unique environment of Macquarie Harbour.

Data collected between 2021 and September 2024 suggests the population may be stabilizing after a decline reported over a decade leading up to 2020.

“Although the population remains significantly lower than historical levels, catch per unit effort data—a standard measure of relative abundance—shows the skate population has stabilized since 2021 and there has been no overall further decline,” IMAS researcher and Maugean skate captive breeding program leader Professor Jayson Semmens said.

“It takes approximately six years for Maugean skate hatchlings to reach maturity, so while immediate recovery of adult biomass is not expected, the presence of juveniles at a similar proportion relative to adults in the sampling as we were seeing in 2014 is a positive sign. Continued monitoring will be crucial to understanding the long-term trajectory of the species.”

While the skate remains endangered, IMAS researcher Dr. David Moreno said it was too early to predict long-term outcomes and stressed the importance of ongoing research and monitoring to guide effective conservation efforts.

“Additional data are needed to determine whether the observed presence of young skates will lead to a sustained recovery,” Dr. Moreno said. “Updated population models and action plans are needed to ensure the species’ survival in Macquarie Harbour, its last remaining habitat.”

The extended dataset and early signs of stabilization in the population underline the critical need for ongoing support and monitoring efforts, which will be pivotal in guiding effective conservation efforts for the Maugean skate.

“This is science in action,” IMAS Fisheries and Aquaculture Centre Head Professor Sean Tracey said.

“All the work presented to date has been based on the best available information at the time. Funding support from the Tasmanian and Australian governments has helped us improve our understanding of the Maugean skate. As we learn more, our role is to ensure that we’re updating and reassessing that information so that decisions are made based on the best contemporary data.”