Texas A&M develops diagnostic index for canine GI issues

More than 10% of all new veterinary visits are related to gastrointestinal (GI) disease in dogs and cats, according to research. Identifying when a patient’s microbiome is abnormal can help with deciding whether they have acute or chronic GI dysfunction.

A research team from the Texas A&M University School of Veterinary Medicine & Biomedical Sciences’ Gastrointestinal Laboratory (GI Lab) has validated a new diagnostic index to help veterinarians assess chronic GI dysfunction in dogs, while also assisting to diagnose and treat GI disease in the future.

“For more than 20 years, we’ve been working on better understanding the microbiome and how it relates to health and disease,” said Dr. Jan Suchodolski, associate director of research for the GI Lab. “A big challenge, until recently, is how do you define a normal or abnormal gut microbiome and how do you moderate it?”

In an August 2023 article in the journal “Animals,” GI Lab researchers validated their Dysbiosis Index (DI) using the microbiomes of 296 dogs to demonstrate that their index is an accurate diagnostic tool for distinguishing between acute and chronic GI dysfunction, as well as detecting non-GI disorders. Dysbiosis is defined as a disruption in the gut microbiome, typically a reduction in microbial diversity characterized by a loss in beneficial bacteria.

The index works by identifying dysbiosis by tracking the levels of various bacteria over time. Reference intervals allow researchers to tell how much the microbiome shifts. The DI accurately predicts the total shifts, as can be observed with DNA sequencing.

The DI was licensed through Texas A&M and Idexx Laboratories and is being offered through both.

“Chronic GI disease often is already present before clinical signs start,” Dr. Suchodolski said. “So finding specific markers can tell us about the state of the organ.

Clinical signs of GI disease can be mild, such as diarrhea or vomiting, or some can be signs of more severe dysfunction in the GI tract that’s chronic. Being able to better assess if the dysfunction is going to be long term is critical for veterinarians and clients when managing GI disease.

“The good news is that the majority of animals still respond with dietary modulation.” Dr. Suchodolski said.

Biomarker assessment is only one part of assessing GI health, and the GI tract should be treated as a whole system, he said. “Often people focus on moderating one part and forget that they all interplay with each other.”

Veterinary professionals don’t often realize the long-term chronic changes that occur from GI disease, Dr. Suchodolski said. In the future, researchers hope to better understand additional and earlier markers, because the earlier they intervene, the more hope there is that the changes in the microbiome can be reversed, he said.