Why do horses drool?


It has always cracked me up: ponies who get into clover and drool like leaky faucets. Until recently, I did not know the reason they drool is because of a toxic fungus that grows on the clover. (And I did not know its comical names: Saliva Syndrome! Slobbering Horse Syndrome!)

The Rhizoctonia leguminicola fungus, also called “black patch” because of the (sometimes microscopic) black spots that form on affected leaves, grows on white and red clover, and alfalfa. It produces the toxin slaframine, which can increase horses’ salivary gland output. In more extreme cases, it can also cause increased tear production and urination, difficulty breathing, and–rarely–even abortion. Some horses have have allergic reactions on facial skin that comes in contact with the fungus.

Horses that are more affected than others can either be especially sensitive to the toxin, or just prefer clover, so consume a larger quantity of slaframine.

“Black patch” prefers humid weather, so it is most prevalent in Spring and Summer. To control growth of the fungus, keep your pastures healthy. Clover thrives in stressful conditions, such as droughts, extended wet periods, poor soils, and over-grazing, so rotate your pastures to minimize stress. Use chemical treatments carefully to avoid harming your animals. Note that the fungus can also be present in hay containing affected clover or alfalfa.







How to help a choking horse

I once knew a horse who died from choking on his breakfast. Bob got some food lodged in his esophagus, and his owner turned him out in the hope that the food would work itself loose. It stayed stuck, and by the time the vet was summoned, part of Bob’s esophagus had been without blood flow for so long that it had died. The horse, a young, talented Thoroughbred, was euthanized.

So when my own (not-so) young, talented Thoroughbred stopped hoovering her dinner the other night, curling her lip repeatedly in distress, I felt a bit panicked. My barn manager told me to take her for a walk to see if she’d work it out. That worried me, remembering what the vet said about turning out poor Bob, but her rationale was sound:

  • One reason horses choke is because getting fed from a hanging bucket puts their neck into an unnatural position for eating
  • Letting them stretch out their neck may help them work the blockage free
I also massaged my horse’s throat and watched for swallowing–a good sign–and discharge from her nostrils–a bad sign. It only took a few minutes before I saw swallowing activity in her neck, after which she stopped curling her lip and showed interest in grazing.
We were lucky: in reading up on horse choking, I saw many stories involving sticking tubes down horses’ noses and attempting to flush out the blockage with water. And those were the success stories: some horses died directly from the choking, and others died later from infections stemming from liquid in their lungs from coughing or flushing.Here are some tips I learned in my research:

Signs of choking

  • Stopping eating mid-meal
  • Coughing
  • Visible discomfort (curling of lip, for example) or even distress
  • Discharge from nostrils, or excessive saliva
  • Lump in throat that you can see or feel


  • Keep your horse up-to-date on his dental work. Sharp teeth can cause poor chewing, and large pieces of food are more likely to get lodged on the way down
  • Put your horse’s food as close to the ground as possible
  • If the food is very dry, wet it to help it move down the horse’s esophagus
  • If your horse eats too fast, put a few large rocks in his bucket that he’ll have to work around, to force him to slow down (also works for slowing down ravenous Labradors!)
  • Give your horse as much grazing time as possible, so he won’t be (as) starving at meals

What to do if your horse is choking

  • Remove his food
  • Keep him still, and encourage him to relax and stretch his head down
  • Call the vet. If necessary, she’ll run a tube down your horse’s nose and into his esophagus, and attempt to flush the blockage out with water. She may even need to sedate him or give him IV fluids to keep him hydrated.
  • Don’t try anything Heimlich-esque: that works on humans because the blockage is in their windpipe, so forcing air through can clear the blockage out, but when a horse chokes, the blockage is in his esophagus.

Choke can also be caused by growths or scars in the esophagus, so your vet may want to scope the esophagus after freeing the blockage to see what’s going on down there. If your horse has choked before, he may be more susceptible to future choking, due to scar tissue buildup.Be aware of the causes and signs of choking, and if your horse chokes, hopefully the tips above can help you quickly resolve the situation with minimal stress for your horse and yourself!