Can Weight Loss Predict Chronic Grass Sickness Outcomes?

Weight loss–both the amount and rate–can help predict chronic equine grass sickness survival, researchers found.
Please login

No account yet? Register


Chronic equine grass sickness (EGS) is a potentially deadly condition estimated to affect more than 3% of the equine population in some parts of the United Kingdom. It can cause sudden and extreme weight loss, and researchers have long thought that only horses with mild cases of this chronic disease have a chance at recovery. But is there a way to predict which horse will survive? Researchers recently examined affected horses’ weight loss to find out.

Not surprisingly, chronic EGS is associated with grazing pasture full- or part-time. Although the reasons remain unknown, data suggests that production of toxins from Clostridium botulinum within the gut could be to blame. Damage to parts of the nervous system involved in involuntary functions, mainly gut paralysis, can show outwardly as colic, reduced appetite, difficulty swallowing, and rapid weight loss.

Rachel Jago, BVM&S, MRCVS, and colleagues from the University of Edinburgh Royal (Dick) School of Veterinary Studies and Roslin Institute, in Scotland, tested whether body weight changes could help predict the outcome of chronic equine grass sickness.

First, the team reviewed case records of horses admitted to the Dick Vet Equine Hospital from 1998 to 2013 for chronic equine grass sickness. All horses received a strictly managed diet consisting of highly palatable concentrate feeds while under hospital care. Initially, the team fed horses every two hours and, as meal tolerance increased, they fed the horses more food less frequently. Medications required to treat associated colic, such as analgesics, and other conditions remained part of daily management as necessary. Hospital staff recorded each horse’s body weight at admission and about every two days thereafter

Create a free account with to view this content. is home to thousands of free articles about horse health care. In order to access some of our exclusive free content, you must be signed into

Start your free account today!

Already have an account?
and continue reading.


Written by:

Kristen M. Janicki, a lifelong horsewoman, was born and raised in the suburbs of Chicago. She received her Bachelor of Science degree in Animal Sciences from the University of Illinois at Urbana-Champaign and later attended graduate school at the University of Kentucky, studying under Dr. Laurie Lawrence in the area of Equine Nutrition. Kristen has been a performance horse nutritionist for an industry feed manufacturer for more than a decade. Her job entails evaluating and improving the performance of the sport horse through proper nutrition.

Related Articles

Stay on top of the most recent Horse Health news with

FREE weekly newsletters from

Sponsored Content

Weekly Poll

sponsored by:

What signs does your horse show when he has gastric ulcers? Please check all that apply.
87 votes · 216 answers

Readers’ Most Popular

Sign In

Don’t have an account? Register for a FREE account here.

Need to update your account?

You need to be logged in to fill out this form

Create a free account with!