It happened again: Your horse was fine for the entire weekend of riding, but when you got him ready for another weekend packed with activities, you discovered his hind limbs were swollen. You know it’s not overuse; the boarding barn provides limited turnout, and you usually can’t ride Monday through Friday, so your weekend warrior gets plenty of stall rest during the week. He’s not lame, and after you start working him, the swelling goes down, but still, it’s a concern. One of the other riders said your horse is “stocking up,” but that it’s nothing to worry about. What’s going on?
“Strictly speaking, stocking up is merely swelling of the lower limbs due to decreased activity and pooling of blood and lymph (clear fluid drained from tissues, that circulates within the lymphatic vessels and contains fats, proteins, and specialized cells) in the extremities,” says
Jennifer L. Davis, DVM, PhD, Dipl. ACVIM, ACVCP, clinical assistant professor of equine medicine and clinical pharmacology at North Carolina State University College of Veterinary Medicine. “It is a very benign condition caused by lack of movement. It’s not painful for the horse and doesn’t cause changes in attitude or appetite.”
Stocking up is separate from–and should not be confused with–other veterinary conditions that result in edema (fluid swelling) of the lower limbs (see “When It’s Not Stocking Up” on page 78 for further details).
The condition, also known as static congestion, generally occurs after horses that have had normal activity are stall-bound for two or three days, notes racehorse veterinarian Steven Allday, DVM, of Elite Veterinary Medicine in Simpsonville, Ky. “It seems to be more common in heavy-muscled horses like Quarter Horse types,” he explains. “They have more body mass over a