What you see. The starting point for addressing any equine health related issue is your observation.


Cheeks or Jowls Look Hollowed Out


The main cheek muscle is the masseter, an important chewing muscle. In a normal horse, the jowls are fleshy and full. Stallions are known to have particularly full jowls.

A hollowed out appearance of the cheek muscles can result from a variety of problems.

This observation is commonly made in horses with "shear mouth" or steep angle of occlusion that prevent normal chewing movement. In this case, there is often very little side to side movement of the jaw and the muscles waste away because of disuse. Any condition that causes pain while chewing can reduce normal movement of the jaws and can also cause masseter muscle wasting.

Older horses that seem to chew normally can also have muscle wasting here. This area, like the top-line tends to lose muscle mass as a horse ages. However, older horses with poor teeth or other treatable dental problems that cause difficulty chewing often appear to have hollowed-out jowls or cheeks. This can be symmetrical or can affect one side more than the other.

Injuries that damage the muscles or the nerves that supply the chewing muscle will also cause muscle wasting and a hollowed out appearance. This usually occurs on only one side.

  • Code Yellow

    Contact Your Vet at Your Convenience for an Appointment

your role


What To Do

Assess your horse's general health using the Whole Horse Exam (WHE), and assess their mouth and teeth to the best of your ability (wear gloves). Watch the horse eat, and note whether they have difficulty or are eating slowly. Does this appear to be a problem on both sides, or is it just one-sided?

Look for evidence of poor chewing such as quids of chewed hay in the environment, and assess the fiber length and general appearance of the manure.

Consider the horse's Body Condition Score (BCS) and whether this has changed. Contact your vet with your findings and concerns.

your vet's role

Your vet considers this observation in light of other factors. They may recommend a dental examination and want to assess chewing function to determine whether underlying dental problems contribute to this observation.

Once a diagnosis is made, potential treatments can be discussed.
Questions Your Vet Might Ask:
  • How old is the horse?
  • Is the problem present on both sides?
  • Does the horse seem to be having difficulty eating or dropping feed?
  • How is your horse's body condition and weight?
  • What is the horse's age, sex, breed and history?
  • Has your horse lost weight recently?
  • Is the horse also spilling or dropping feed, or quidding?
  • Does the horse have diarrhea or loose manure?
  • Does the manure have large plant fibers in it?

Diagnoses Your Vet May Consider

The cause of the problem. These are conditions or ailments that are the cause of the observations you make.

Very Common
Less Common
more diagnoses

further reading & resources

Author: Doug Thal DVM Dipl. ABVP