COPD in Horses

Chronic obstructive pulmonary disease (COPD) is also known as recurrent airway obstruction (RAO) or Heaves.  It is a problem that can be treated, but, once a horse has it, never cured.

With my mare, it began slowly, a cough when we would pick up the trot, then nothing more that day.  An occasional cough when she was in her stall.  Then it became several coughs while trotting, often bringing us back to the walk until she cleared her throat.  I blamed it on the cold, dry weather, added some oil to her feed, and soaked her hay in the barn at night.  The hay was a little dusty, but not moldy.

It seemed to do the trick; she stopped coughing and we could go back to full work.  About a month later however, she was coughing on a trail ride, couldn’t trot, and was coughing while standing still in her paddock.  I noticed that she, Indy, and several other horses in the barn weren’t finishing their hay.  Upon closer inspection I saw that we had gotten in a batch of hay that was not only dusty, but had mold spores in it as well.

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Do you know what moldy hay looks like?  This is a drastic example; it may not be this obvious.  Smell it, feel it, shake it out.  If it makes you cough, don’t feed it!  Mold cannot be soaked out of hay – your best bet is to throw out the entire bale.

I of course was furious, as now my horse has a lifelong issue and will require more work to maintain on my end.  I decided to explore more into this affliction so I can best manage her.

COPD can manifest itself in numerous ways in the horse.  It most commonly shows as a cough which is caused by the horse trying to expel mucus through narrowed airways.  The narrowing can be caused by inflammation (due to irritation from allergens),  tightening of surrounding muscle, and thickening of the tissue surrounding the airway.  When the cells in the lungs are exposed to allergens, such as fungal spores, mold, and dust, the body responds by producing cells that thicken the tissue and produce mucus – the body’s defense mechanism.  Extra effort is required for the horse to bring their regular volume of air through these thickened, narrow passageways.  The more the horse is exposed to the allergen, the more sensitive the lungs become, the more difficult it is to breath.  This shows up as an increased respiratory rate (above the normal 8-12 breaths per minute) and a longer recovery after exercising.

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Mucus forms not just in the lower airway, but throughout the upper airway as well.

In addition to the cough, horses may also develop nasal discharge.  The discharge comes from increased airway secretions – the body’s attempt to heal itself.  These secretions can also cause further obstruction of the airway.

The term heaves came from the increased respiratory efforts required by the horse, simply put, labored breathing.  These horses will often have a “tucked up” appearance, with a line of abdominal muscles called the “heave line”.  This is caused by the increased effort by the abdominal muscles to force the air out of the lunges during expiration.  When listening with a stethoscope, one will often hear wheezing when the horse breathes.

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Abdominal muscles creating a “heave line”

An extreme complication of heaves is a bacterial infection (such as pneumonia) resulting from bacteria becoming trapped in the airway.

Diagnosis of this condition is based mostly on history.  Your vet will want to know when your horse has coughed and any discharge they have been having.  A physical exam may include a re-breather test, where a bag is placed over the horses nose for a brief period to increase their respiratory rate.  The vet will listen with a stethoscope for any abnormal breath sounds.  This may also induce coughing from your horse.

A Bronchoalveolar lavage (BAL) is another test that can be done, which would show whether or not there is inflammation in the lower airways and rule out infection.  This test is not usually necessary to diagnose COPD, but rather used to rule out other issues.

If your horse is displaying any of these symptoms, no matter how minimal, it is best to take action now before it gets any worse.  In my next blog post, I’ll talk about prevention and maintenance.

Indy Learns to Lunge

Everyone keeps asking me ” when are you going to get on Indy? When do you think you’ll start riding him?” My answer is the same every time. When he is ready.  I’m in no hurry. There is no agenda. Horses will tell you when they are ready, if you actually listen to them.  I pay careful attention to Indy’s attitude, body language, and especially to the limits of his attention span.  There is no point in “drilling” him and no benefit to pushing him beyond what his young brain can handle right now.

On the other hand, I do have to keep his mind busy.  That’s the trouble with the smart ones; they need new challenges.  While Shady would behave and perform the same exercises day in and day out, I can feel her spirit diminish if I spend too much time on one idea.  A few years back I had a lovely thoroughbred who would have gladly trotted a 20 meter circle day in and day out all year round.  He was a sweetheart, but not the brightest.  I love the intelligence I am seeing in Indy.

One night, without having planned to do it, we lunged.  He had been inside due to lousy weather, so I brought him in the indoor to stretch his legs.  He ran and jumped, bucked and reared, entertaining himself and myself.  I can see so much of Shady in him.  He will run up to me, just like her, stop, blow loudly out his nose, and explode off again.  After about 20 minutes he stopped, licked and chewed, and calmly walked over as if to say “ok, I’m all done here.”

I stared at him, standing quietly and submissively next to me, as he huffed and puffed. I put his halter on and we began walking. We practiced a few transitions between walk and halt as we walked.  He’s very good at voice commands.  As we walked, I slowly let the lead out and we walked in a large circle, with him at the end of the lead.  We did more transitions. He listened, staying out on his circle.  We switched sides. He listened. He licked and chewed and showed all the submission signs, behaving like a pro.  I unclipped his lead and we cooled out together, walking along side by side without speaking.

A few nights later we repeated the process, only this time I put a lunge line on.  He walked on, making the circle bigger and bigger, until it was a full 20 meter circle.  He walked, he halted, and he walked on again.  He just got it.  Most other youngsters I’ve started have needed a helper to lead on the outside of the circle.  The exception, of course, being Shady, who also just got it.

About a week later, we tried again, and added in a trot transition in each direction.  He pulled a little, but stopped when he realized he was at the end of the line.  Our circle may have bulged out in places, but overall we still had a round shape.

I bought him his own surcingle, put it on, snugged it up, and nothing happened.  We walked, then tightened again and nothing happened. He didn’t care.  I’ve put plenty of things on him before, just getting him used to blankets, pads, etc being on him. Now it doesn’t faze him.

I left him run around with the surcingle on, giving him a chance to figure it out on his own.  He was his usual self, bucking leaping and playing, seemingly not noticing the different sounds and feel of the surcingle.  We then did a lunging session with it on, doing three trot transitions and three walk/halt transitions in each direction with lots of praise.

I keep our sessions very short, with not more than 10 minutes total on the lunge.  The majority is at the walk, with no more than 2-3 trot circles at a time.  I keep our circles as big as I can, walking along myself to keep it bigger than the lunge line length.  We don’t canter; maybe a few excited strides here and there but I immediately ask him back to the trot.  We don’t lunge very often and don’t plan to, maybe once per week or less.  There is no need to drill him or stress his joints.  This is all concept training, something we can use to develop our partnership, introduce new things, and give him some semblance of a job.  He seems to take pride in his work.