Ambulatory Equine

09/03/2026

🌱 POISONOUS PLANT #️⃣ — BERMUDA GRASS?! 🌱

Wait… BERMUDA GRASS is on poisonous plant lists?! 😳

Well… sort of.

Bermuda grass is generally rated only 4/10 for toxicity, but here's the surprising part:

🐴 Horses consuming Bermuda grass hay have been reported to be nearly SIX TIMES more likely to develop colic than horses consuming other grass hays.

The biggest concern is mature, coarse Bermuda grass hay.

It isn't necessarily a toxin causing the problem. The long, coarse fibers can be difficult for a horse with poor dentition to adequately chew and break down before swallowing.

A horse with balanced, functional teeth should thoroughly masticate its hay, reducing the fibers to roughly 1/4" pieces before swallowing. But horses with dental disease, missing teeth, sharp points, or other problems that interfere with chewing may swallow much larger pieces.

Those long fibers can contribute to severe ileal impaction colic, that's where the small intestines meet the cecum.

And here's another thing to think about:

🦷 If your horse isn't chewing efficiently, you're potentially paying for feed that your horse isn't able to utilize as efficiently.

Proper mastication helps break feed down so nutrients can be more effectively digested and absorbed. If large pieces are being swallowed, you're not necessarily getting the same nutritional value from every mouthful.

And an ileal impaction colic is a very different situation from a simple gas colic.

💥 These cases frequently require veterinary intervention, which may include nasogastric tubing and administration of water, electrolytes, magnesium sulfate, mineral oil, probiotics, and other treatments as indicated. Some severe cases can even require surgery.

There are also other potential problems associated with Bermuda grass under certain environmental conditions, particularly in warm, humid climates. For example, fungal contamination such as ergot can cause toxicity.

Fortunately, that's generally not the Bermuda grass concern we worry about here in Arizona.

So let's come back to the surprising part…

😳 Did you know that horses consuming Bermuda grass hay can be nearly SIX TIMES more likely to colic?

That's pretty amazing, isn't it?

The takeaway isn't necessarily “Never feed Bermuda grass.”

It's:

🦷 KEEP THOSE TEETH HEALTHY AND FUNCTIONAL.

Regular equine dental examinations—at least annually for most horses, and more frequently when dental problems are present—help make sure your horse can properly masticate the feed you're paying to put in front of them.

Healthy teeth → better chewing → better utilization of feed → potentially fewer problems.

One simple way to get an idea of how effectively your horse is chewing is to look at what comes out the other end. 💩

Take a fresh manure ball and gently break it apart. You should see the hay and forage fibers reduced to relatively small pieces, with an average fiber length of around ¼ inch (5–6 mm). If you're consistently finding fibers that are ½ inch, 1 inch, or even longer, that may be a sign that your horse isn't adequately masticating its feed.

🦷 If you're seeing long, recognizable pieces of hay in the manure, the first thing I'd recommend is having your horse's teeth professionally evaluated.
It's a simple observation that can give you valuable information about what's happening before the feed ever reaches the stomach.

Sometimes the most important part of nutrition happens before the feed ever reaches the stomach. 🐴🦷

09/01/2026

Attn: Verde Valley and Phoenix Valley
🌿 SILVERLEAF NIGHTSHADE: A PRETTY FLOWER WITH A SERIOUS SIDE
If you have horses in Arizona, chances are you have seen silverleaf nightshade (Solanum elaeagnifolium)—whether you realized what it was or not.
It is one of those plants that I think every horse owner should learn to recognize.
Silverleaf nightshade is a deep-rooted perennial that thrives in our dry Arizona soils. It has distinctive silvery-gray, fuzzy leaves, purple flowers, prickly stems, and round yellow-to-orange berries that look a little like tiny tomatoes. It spreads by both seeds and an extensive underground root system, which is why mowing it repeatedly doesn't necessarily make it go away.
🌱 The good news?
Most horses don't particularly like nightshade. It is not exactly their first choice on the buffet.
The problem is that horses don't always get to choose.
When desirable forage becomes limited, horses may begin eating plants they would normally avoid. And one of the biggest concerns is hay contamination. Nightshade mixed into baled hay can be much harder for a horse to identify and reject. And importantly, drying does NOT make nightshade safe.
Nightshade plants contain toxic alkaloid compounds, including steroidal glycoalkaloids. These compounds can irritate the gastrointestinal tract and can also produce neurologic effects.
Signs of nightshade poisoning can include:
• Decreased appetite
• Excessive salivation
• Colic
• Diarrhea, sometimes with blood
• Depression or lethargy
• Weakness
• Tremors
• Incoordination/ataxia
• Dilated pupils
• Progressive weakness or paralysis
• Recumbency
• Abnormal heart rhythms
• Rapid heart rate and weak pulse
• Difficulty breathing
• Coma
• Death in severe cases
The severity of poisoning is highly variable. It depends on the species of nightshade, the plant part consumed, the amount eaten relative to the horse's body weight, the maturity of the plant, and environmental conditions.
Interestingly, the most toxic plant material isn't necessarily the same at every stage of growth. Toxin concentrations can vary substantially, and plant stress and growing conditions can influence toxicity.
🚨 AND HERE'S THE PART I REALLY WANT HORSE OWNERS TO KNOW:
There is a documented concern involving nightshade exposure and ivermectin.
There have been reports of horses developing severe neurologic signs consistent with ivermectin toxicity after receiving an appropriate dose of ivermectin while also having access to toxic Solanum plants, including silverleaf nightshade. In one reported group of horses, the ivermectin dose itself was not excessive, yet the horses developed severe neurologic disease.
The suspected interaction is complicated. Nightshade toxins may increase ivermectin absorption or decrease its elimination, and there is evidence suggesting that Solanum exposure may also interfere with the blood-brain barrier, allowing more ivermectin to reach the brain. The exact contribution of each mechanism is not completely established.
The resulting neurologic signs can be dramatic—severe depression, ataxia, drooling, head pressing, weakness, and potentially death.
This is why I don't want horse owners to think:
"My horse eats a little nightshade and seems fine, so it's probably not a problem."
The concern may not simply be whether the horse eats enough plant material to become obviously poisoned.
Ongoing exposure may also matter when medications such as ivermectin are administered.
That doesn't mean you should panic about every dose of ivermectin, and it does NOT mean ivermectin should never be used. It means that if you know your horse has access to significant amounts of silverleaf nightshade—particularly if it is present in the pasture or hay—tell your veterinarian.
🌾 Prevention is much easier than treatment.
✔️ Inspect your pastures regularly.
✔️ Learn to recognize silverleaf nightshade.
✔️ Inspect hay before feeding it.
✔️ Be especially suspicious of hay containing unfamiliar weeds.
✔️ Don't assume drying makes a toxic plant safe.
✔️ Never feed horses discarded potatoes or potato peelings, particularly green, sprouted, or damaged potatoes.
✔️ If you find nightshade in your pasture, remove it whenever practical and address the underground root system—not just the part sticking above the ground.
If you suspect your horse has eaten nightshade, call your veterinarian promptly—even if your horse looks normal.
Take photographs of the plant and, if possible, save a sample of the suspected plant or contaminated hay for identification. Do not delay veterinary care while trying to collect a sample.
There is no simple antidote that makes nightshade poisoning disappear. Treatment is primarily supportive and may involve gastrointestinal decontamination when appropriate, fluids, pain control, neurologic support, and treatment of complications.
Know your weeds. Know your hay. And know what's growing in your horse's pasture.
Because sometimes the most dangerous plant in the pasture is the one your horse normally wouldn't choose to eat. 🌿🐴

08/26/2026

🌿 Datura: A Beautiful Flower That Can Be Dangerous to Your Horse

Horse owners in Arizona—please take a look around your pastures, pens, hay, and fence lines. Datura is flowering right now, and it is a plant you do NOT want your horse eating. It is considered a 10/10 toxicity level.

Datura goes by many names, including Sacred Datura, Jimsonweed, Thornapple, Devil’s Trumpet, Angel’s Trumpet, Hell’s Bells, Devil’s W**d, Witches’ W**d, Mad Apple, and Jamestown W**d. Several Datura species occur in the Southwest, including Datura stramonium and Datura meteloides/inoxia.

It is a tall, bushy plant with large, hairless leaves and beautiful white or sometimes violet-tinged trumpet-shaped flowers. After flowering, it produces a distinctive spiny seed pod that eventually splits open and releases numerous flat seeds.

You may find Datura growing spontaneously in sandy or disturbed areas, along roadsides, near waterways, in pastures, and around fence lines. It is also sold as an ornamental plant, so it can show up in yards and landscaping as well.

🌱 Why should horse owners care?

Every part of the Datura plant is toxic, with the seeds containing particularly high concentrations of toxic alkaloids such as atropine, scopolamine, and hyoscyamine.

Fortunately, fresh Datura has an unpleasant odor and taste, so horses generally avoid it when they have plenty of other forage. The problem is that horses may eat it when forage is limited—or accidentally consume it when the plant is mixed into hay because once dried, it is a bit more palatable. Seeds can also contaminate feed or be eaten from short pasture grass.

And toxicity can be very unpredictable. The concentration of toxic compounds can vary from plant to plant, leaf to leaf, and depending on the season.

🐴 What can Datura poisoning look like in a horse?

Signs can develop within minutes to several hours after ingestion, depending on the amount consumed.

You may see:

• Excessive thirst or seeking water
• Dilated pupils
• Increased heart rate
• Increased respiratory rate leading to respiratory distress
• Decreased gastrointestinal motility and gut sounds, leading to gas colic
• Or diarrhea
• Depression or lethargy interspersed with periods of restlessness, agitation, or abnormal behavior
• Incoordination
• Trembling or muscle twitching
• Convulsions
• Coma
• In severe cases, death

⚠️ What should you do if you find Datura?

Don't wait for your horse to eat it. Remove it.

Pull plants while wearing protective gloves, preferably when the soil is moist after rain or watering the day before. Try to remove the plant before it goes to seed.

And don't forget about the fence line. If your horse can reach through or over the fence to nibble a plant, it's still a potential exposure.

Do not burn pulled Datura plants. There is concern about exposure to toxic compounds in the smoke.

A few plants can sometimes be pulled mechanically, while larger infestations may require appropriate herbicide control. If chemical control is necessary, make sure the product is appropriate for the location and follow its label carefully, particularly around grazing horses.

🌸 One more important point: Datura is sometimes intentionally planted as an ornamental because those flowers are so beautiful. Please think twice before planting it anywhere that horses—or other livestock—could access it.

I have personally seen a lot of Datura just yesterday along I-17 near the Verde Valley, around the Verde River, and less commonly along roadsides in the Phoenix Valley so this isn't just a plant that horse owners might encounter somewhere else. It is out there in our Arizona environment.

The best protection is knowing what it looks like and keeping it out of your horse's reach. If you're seeing these plants flowering right now, this is a good time to identify them and deal with them before those spiny pods mature and spread their seeds.

If you're not sure whether a plant growing near your horse is Datura, take a picture and have it positively identified before assuming it is harmless.

🐴🌿 Please share this with other Arizona horse owners. It may help someone recognize a dangerous plant before their horse gets into it.

— Ambulatory Equine Veterinary Services

08/25/2026

Verde Valley horse owners — I’ll be in the area Monday and Tuesday during the first week of September offering equine veterinary appointments.
I’ll be available for general care, dentistry, vaccinations, nutritional consultations, and other routine veterinary needs.
If you’ve been putting off an appointment because your regular veterinarian is booked out, feel free to reach out.
Ambulatory Equine Veterinary Services
Phoenix Valley–based equine veterinarian
📞 480-266-0485

08/21/2026

I'm starting a little series on horse behavior after being inspired by Dr Temple Grandin. Don't you just love the ai pic? 🤣

🐴 Where Did the Monster Come From?

Ever wonder why your horse can walk past something 100 times without a problem…and then suddenly act like it has encountered a three-headed monster? 👹
There’s a fascinating concept in horse behavior that explains some of this: horses are very sensory-specific thinkers.
What does that mean?
Your horse may learn that that particular thing is safe in that particular configuration.
But change the picture…and suddenly you've got a brand-new problem.
Think about a chair in the arena.
Your horse walks past it every day.
No problem.
Now turn the chair around.
👀 “WHAT IS THAT?!”
To us, it's obviously the same chair.
To the horse, the visual picture has changed dramatically.
The same thing can happen with:
• A trailer viewed from a different angle
• A tarp blowing instead of lying flat
• A flag moving instead of hanging still
• A shadow that wasn't there yesterday
• A saddle or pad that feels completely different
• A familiar object in an unfamiliar location
This is one reason simply saying, “But he's seen that before!” doesn't necessarily mean much to the horse. 😂
He may have seen something similar, but he may not have experienced that exact sensory picture.
So when you're training your horse to accept something new, don't just ask:
“Has he seen it before?”
Ask:
“Has he experienced it in all the different ways he's likely to encounter it?”
That little change in perspective can make a BIG difference in how we train and handle our horses.
And honestly…sometimes the “monster” really is just a chair. 😆🐴

08/19/2026

08/18/2026

Where Do the Beans Hide? 🫘🐴
If you have a gelding, you’ve probably heard about “the bean.” But where does that little troublemaker actually hide?
The answer is a little more complicated than you might think!
A common place for a bean to form is in the glandis fossa, the groove located on either side of the urethral process. Sm**ma and cellular debris can accumulate here and, over time, become a firm mass.
But there’s another place that is easy to overlook: the urethral sinus, a small recess associated with the urethral process.
These anatomical pockets are exactly why a thorough examination during sheath cleaning is important. Simply cleaning the visible portions of the p***s may not be enough to find everything hiding in those deeper recesses.
🎥 Take a look at the video to see the anatomy on a pink-skinned horse. The anatomy is particularly easy to appreciate, including the glandis fossa and urethral sinus.
And remember: not every gelding needs routine aggressive sheath cleaning. Knowing the anatomy—and knowing where to look—is much more important than simply cleaning more often.
🫘 So… where do the beans hide?
Sometimes, right where you’d least expect them!

10/13/2025

Call today for your free metabolic testing!
DEADLINE TUES OCT 14TH 5PM
I have been offered a free metabolic test from the laboratory and I want to pass this savings along. This means we would be testing for Equine Metabolic Syndrome, otherwise known as EMS and PPID (pituitary pars intermedia dysfunction), which used to be called Cushing’s disease. If your horse has any of the following signs; takes a little longer to shed out than other horses, is overweight, especially if they have a cresty neck or horizontal rings around the hoof and has not been tested previously, your horse would be eligible for this free testing. A more complete list of signs is available on a post dated June 8, 2023 from my Ambulatory Equine page. https://www.facebook.com/photo/?fbid=723912376406594&set=a.478379507626550
You would still be financially responsible for the trip charge and a comprehensive physical exam fee at time of service, but your laboratory testing would be at no charge. The laboratory testing is a $330 value, that you would be saving. When you call for an appointment, we can give you an estimate based on what city your horse is in. Please contact Dr. Susan Roach from Ambulatory Equine at (480) 266-0485 to schedule an examination in the East Valley or in the extended service range before this free testing expires!

10/08/2025

Call today for your free metabolic testing!
I have been offered a free metabolic test from the laboratory and I want to pass this savings along. This means we would be testing for Equine Metabolic Syndrome, otherwise known as EMS and PPID (pituitary pars intermedia dysfunction), which used to be called Cushing’s disease. If your horse has any of the following signs; takes a little longer to shed out than other horses, is overweight, especially if they have a cresty neck or horizontal rings around the hoof and has not been tested previously, your horse would be eligible for this free testing. A more complete list of signs is available on a post dated June 8, 2023 from my Ambulatory Equine page. https://www.facebook.com/photo/?fbid=723912376406594&set=a.478379507626550
You would still be financially responsible for the trip charge and a comprehensive physical exam fee at time of service, but your laboratory testing would be at no charge. The laboratory testing is a $330 value, that you would be saving. When you call for an appointment, we can give you an estimate based on what city your horse is in. Please contact Dr. Susan Roach from Ambulatory Equine at (480) 266-0485 to schedule an examination in the East Valley or an hour beyond before this free testing expires!