Dr. Tania Sundra

28 June 2020

Why Is My Horse Girthy ?

Check out our YouTube video showing our mobile gastroscope in action!

Girthiness is a common term used do describe an adverse behavioral response to the girth being tightened. Some horses will pin their ears back, some will kick, some will turn to bite and others may run backwards or even buck when the girth is being tightened.

A recent 2019 study identified the underlying reasons why horses present with this issue. The study looked at the medical records of 37 horses evaluated at the University of California, Davis with a presenting complaint of girthiness.

  • 12 horses were diagnosed with gastric ulceration,
  • 10 with various orthopedic problems,
  • 3 with ill-fitting saddles,
  • 1 with reproductive tract neoplasia, and
  • 10 with various diseases including liver abscess, sand impaction, sternum pain, ovarian tumour and urinary tract infection.

In the case of gastric ulceration, these were diagnosed on gastroscopy. The horses were treated with omeprazole and the clinical signs were resolved following treatment according to the owner’s feedback. Of the horses diagnosed with orthopedic issues, the underlying reasons ranged from vertebral osteoarthritis, bone spavin and front limb lameness.

Approximately 30% of horses presenting with “girthiness” were due to gastric ulcers.

Saddle Fit

Saddle fit evaluations revealed various issues including a broken tree, excessively narrow gullet and uneven flocking. Clinical signs resolved with an appropriate saddle in addition to acupuncture and chiropractic treatment. In 2013, a study evaluating the problems associated with poor saddle fit showed that ill-fitting saddles contribute to epaxial musculature atrophy and pain, localized pain underneath the saddle, and abnormal wear of the hair.

Gastric Ulceration

Why do gastric ulcers cause girthiness ? Well, we need to delve into a bit of neurology to answer this one. If you’re a nerd (like me), keep reading… if not – well done on making it this far but feel free to scroll down!

One theory why this happens is called COMMON POOL THEORY. Simplistically, the nerves which relay information from the lining of the horse’s stomach, are wired into the spinal cord very close to the nerves that relay information from the skin. That information then travels in a single combined nerve tract all the way up to the brain.

When horses develop an ulcer in their stomach, all of a sudden the stomach starts to communicate much more with the spinal cord and brain. What we think then happens is that the the brain misinterprets this as being skin sensation. So we think the gastric ulcer is causing the brain to worry about the skin being touched.


The second theory is may be due to the VISCERO-VISCERAL REFLEX. So this is essentially exactly the same wiring and sending of information to the brain, but what we think happens here is that these signals now effect the blood supply to the muscles of the skin. As horses are ridden, and you start to apply leg aids, the skin muscles start to contract and as it contracts it eventually runs out of oxygen and starts to fatigue.  What we think happens in horses with gastric ulcers is that as the blood supply is reduced, and the skin fatigues more quickly. Therefore, as you start to apply leg aides it starts to hurt, which is why we think the horse starts to resent the application of leg aids.


Those are two very simplistic explanations of the theories that have been proposed on why horses with gastric ulcers present with girthiness and some also resent leg aids.


Where to from here ?

If your horse is girthy or resenting leg aids a complete physical and lameness examination including saddle fit evaluation should be performed to rule out painful conditions. Gastroscopy is recommended to evaluate your horse for gastric ulceration, which was one of the most consistent causes of girthiness in the 2019 study.

Our clients can enjoy the benefit of at-home wireless digital gastroscopy without having to transport their horses into a hospital.
Check out the YouTube video to watch how we perform a gastroscope!

Avon Ridge Equine Veterinary Services is the first equine practice in Australia to offer our clients the state-of-the-art Endo-i Wireless Gastroscope. Call us on 0427 072 095 or book an appointment online today.


Check out our YouTube video showing our mobile gastroscope in action!

About the author : Dr Tania Sundra is the practice owner at Avon Ridge Equine Veterinary Services – a fully mobile equine practice in Western Australia. Dr Sundra graduaded from Murdoch University in 2009 and has worked in equine practice in both the USA and Australia. In 2019, she furthered her education to became a Member of the Australian New Zealand College of Veterinary Scientists, Equine Medicine chapter after successfully completing her membership exams. She was also awarded the Scone Equine Group Prize for achieving the highest score out of all the candidates. She has a keen interest in gastrointestinal medicine and equine nutrition and strongly believes in practicing evidence-based medicine.