Adding a quality prebiotic to the horse's diet can help stabilize the gut microbiome, and some may help bind and remove undesirable toxins before they can pose a threat. | Photo: THe Horse Staff

Q. My 7-year-old Thoroughbred recently contracted coronavirus when it went through the barn where I board. Because his kidney creatinine levels remained slightly elevated after, my vet has continued taking blood samples periodically to make sure all is functioning normally. His kidney function appears to be back to normal; however, we’re still seeing consistently (albeit not alarming) low blood protein levels. Is there something I can do diet– or nutrition-wise to manage this? He currently receives good-quality grass hay, a performance horse feed, and a multipurpose supplement.

A. I’m glad to hear your horse is on the mend. Coronavirus, although rarely fatal, is a nasty illness. Caused by ingesting fecal material from another infected horse, the virus travels through the digestive tract, where it adheres to the lining of the small intestine. Here it replicates, creating large numbers of disease-causing particles.

Infected horses don’t always display symptoms, but when they do the most common ones are weight loss, lethargy, fever, and diarrhea. The horse’s colon can secrete large amounts of fluid as well as proteins into the digestive tract, which is likely the cause of the low protein levels you’re seeing on your horse’s bloodwork panel. The inflammation in the intestinal lining that results from the virus can cause gaps to occur between the cells that line the digestive tract. Typically, the areas where two cells come together in a membrane are called tight junctions, and they result in a barrier between the contents of the gut and the bloodstream. If these tight junctions become disrupted, however, a condition known as “leaky gut” can occur. The gaps between the cells in the membrane allow bacteria and toxins to enter the bloodstream and proteins from the bloodstream to enter the gut