This is probably going to sound bizarre, or maybe not??!! My daughter's OTTB is 13 years old, we know very little of his history, except that when we first met him a little over a year ago he was very underweight. He has since reached a good weight, and from our perspective is healthy and happy. He has always done this weird thing, though. When we first noticed it, it was while she was saddling and we labeled it "cinchy". He would lower his head, slightly close his eyes, and start to buckle at the knees. As soon as she says something or grabs the lead rope he quits and stands straight. He doesn't do it all the time, though. We explored whether it was saddle fit, maybe it was hurting somewhere, but it happens with any and all saddles we've tried. She then started only loosely attaching the girth and walking him around a bit then tightening it and he wouldn't do it then. Well, I read something in Equus a couple months ago about equine narcolepsy, and honestly that's what it looks like he's doing when he does this.......falling asleep! Then yesterday, she was grooming him for longer than normal, because he was muddier than normal, and he did it without a saddle anywhere near him! Like I said, it's not every time she works with him, or every time she saddles him. There are alot of times he just stands for her to groom and saddle him. He also seems perfectly normal once she is on him. No other signs of anything else. I have also read that if you tend to work with your horse during the time of day they like to nap, you can encounter certain behavioral problems. We haven't really paid much attention to the time of day when it typically happens, but she usually works with him shortly after noon during the cooler months and mid morning in the warmer months. We just haven't made any connections as to time of day, at this point. So what do you guys think? In my opinion it wasn't something I felt needed immediate veterinary attention, but what do you think?

What situation is he living in? Is he alone or does he have a herd mate?  The EQUUS article I'm thinking of describes the studies which have shown some horses living on their own don't feel secure enough to fall into REM sleep during the night and consequently nod off in the way you describe during quiet moments in the day.

Here's the article Is Your Horse Sleep Deprived?

Here is a page with some videos

They may offer some insight into your horse's behavior

 

He has his best friend, William, in the pasture with him. They have about 8 acres of open pasture and one large stall that they share. I just did a Google search on Narcolepsy, and definately he is not displaying the symptoms that were described in those articles! It does seem like drowsiness, but he has never actually colapsed. It seems so brief too.

Thanks for your reply! I will check out those links!

It sounds to me as if he's just relaxed and content while you're messing with him. At other times when you're brushing or working with him, (when he isn't doing what you just described), is he licking or smacking his lips or even looking a little 'daydreamy'? At first glance, I'm guessing he's soaking up the love & attention he's getting (sort of like how I'd feel if hubby took pity on me and rubbed my feet.)

shannon7:

is he licking or smacking his lips or even looking a little 'daydreamy'?

 

Well, I wouldn't say licking or smacking his lips, but relaxing his lower lip so much it hangs down! He is a very mellow, laid back horse for the most part. We always tease him about being a "lazy old man", cuz that's what he acts like most of the time. But don't offer him a gallop in the field, he will take you up on the offer, and good luck stopping him!!!

I did wonder if he was just thoroughly enjoying the attention. The link in Jayne-admin's post to the video page was helpful. He does similar to the first video, but we get his attention way before he gets close to actually going down. We've never actually just stepped back to see what he would do. My daughter usually notices his head drop below his withers and she'll say, "Sam, wake up!" and he does! I just didn't want to let some neurological symptom go unaddressed if it could be a sign of something more serious. From my research so far, I think it's a drowsiness issue. He has his buddy with him all the time, but there could be another reason he misses sleep. They do have alot of wildlife visit their pasture. We have seen deer, turkeys, squirrels, and who knows what else goes through during the night when we're not out there. I wouldn't be surprised if coyotes went through on occasion, and there have been cougar sightings in the area (within a mile) , but not on that property that we know of.

I'm with you, DM;  I would be concerned and curious about this behaviour also.  Especially since he has a buddy, because one will almost always stand guard while the other one sleeps, not very often do they lay down and really sleep together (they do, but not as often as only one at a time).  So he should be getting plenty of rest to where he's not falling asleep in the crossties while someone is working on him or around him.  And in the winter time, especially.  Hmmmmm.  Please let us know if you find anything else out.

 This may or may not be relevant to your case, but the first few times my boy started buckling it was while he was under saddle and I was talking to my instructor while mounted. I figured out after some trial and error that he wasn't being bedded deeply enough to be comfortable laying down, and so he wasn't getting hardly any REM sleep. Problem was solved with an extra bag of shavings.

 It's entirely possible that your horse doesn't feel comfortable lying down in his stall or outside. That would be my bet. Even if he has a buddy, many horses won't lie down unless they feel completely comfortable and secure.

Narcolepsy is usually associated with some type of brain lesion. In horses, narcolepsy is often seen as a marker symptom for EPM, a disease spread by ingesting f e c e s from infected Opossums while grazing or from contaminated feed. It's a condition rarely seen in Western states though. And it's usually accompanied by dramatic muscle wasting.

As hard as it may be for you to tolerate, I'd suggest the next time an onset starts, do not intervene and see if the horse does collapse. If he does, it's time for some veterinary consultation. There are some other maladies that might influence his ability to balance properly that are indicated by one droopy ear or one droopy eyelid. If he just wobbles a bit and regains, I'd be more inclined to think he's just very relaxed. ~FH

 ETA- As an afterthought, if he's an OTTB, try running his lip tattoo through the Jockey Club and see if he's ever been back East in his racing career. That might shed some light on whether he's ever been possibly exposed to an EPM vector.

FloridaHorseman:

Narcolepsy is usually associated with some type of brain lesion. In horses, narcolepsy is often seen as a marker symptom for EPM, a disease spread by ingesting f e c e s from infected Opossums while grazing or from contaminated feed. It's a condition rarely seen in Western states though. And it's usually accompanied by dramatic muscle wasting.

As hard as it may be for you to tolerate, I'd suggest the next time an onset starts, do not intervene and see if the horse does collapse. If he does, it's time for some veterinary consultation. There are some other maladies that might influence his ability to balance properly that are indicated by one droopy ear or one droopy eyelid. If he just wobbles a bit and regains, I'd be more inclined to think he's just very relaxed. ~FH

 ETA- As an afterthought, if he's an OTTB, try running his lip tattoo through the Jockey Club and see if he's ever been back East in his racing career. That might shed some light on whether he's ever been possibly exposed to an EPM vector.

 

Yes, that is exactly what I was afraid of (EPM), but I also didn't want to be the hypochondriac that I can sometimes be! I will just not intervene the next time it happens to see how far it progresses. He has never done it anywhere else besides by the barn during grooming and tacking up, never while mounted or just standing elsewhere. Their stall is more of a run in shed, but mostly enclosed, and has no bedding in it. I would love to just go spend 24 hours out there and observe their behaviour and sleeping patterns, not likely to happen, though! I think we will eventually run his tattoo, his is the most legible between the two of them and I have been curious to see what his life on the track was like. If it were EPM wouldn't you see other symptoms too? And wouldn't it progress in a year's time?

 

Dressage Misfit:

If it were EPM wouldn't you see other symptoms too?

Florida Horseman:

it's usually accompanied by dramatic muscle wasting

Dressage Misfit:

And wouldn't it progress in a year's time?

That depends upon the strength of the horse's immune system. EPM can remain dormant for years, only show mild symptoms or sometimes none at all. ~FH

 That was a fascinating article, Jayne, thanks for posting it. It reminded me that I knew a horse this happened to. He was in his mid-20s at the time and was showing signs of Cushing's. My daughter and I rode him, but he was owned by a boarder at the barn so we weren't involved much in his care. It was just like DM says, he didn't do it all the time, but without warning while he was on crossties being groomed his knees would start to buckle. Naturally it scared us and we urged him back up, so he never actually fell. This was before EPM became so well known, but I don't think that's what he had. He was turned out with a number of other horses (not stalled), but as an old guy he wasn't high in the pecking order and it's quite possible he wasn't comfortable. He died about a year later of colic and I hadn't thought of him in a long time.

 

Well, here's an update.....we went to the barn today and once again while my daughter was grooming him he started to buckle. So we just stood back and let it happen to see what he would actually do. He looked exactly like the horse in the first video on the page Jayne linked to in her post! He got really low with his front legs out in front like he was going to lay down, then he snapped out of it and quickly stood back up then didn't do it again. We performed the test exercises suggested in the January and February issues of Equus that test the neurological health of your horse and he seemed to not show any of the suggested signs of neurological deficiencies. Then once saddled my daughter and I both rode out in their pasture and he kept trying to play "race horse" and take off with her. It amazes me that one minute he's falling asleep while being groomed and the next he's trying to take the bit and gallop off in the field. I still wonder if we are catching him at his normal nap time when we go in the afternoon. I won't be able to test that theory until we have some days that are good weather and we're not busy in the morning! Also, contrary to the symptom of muscle wasting, we have been noticing how much MORE muscled he is looking since his rehabilitation from being underweight. His neck, shoulders, and hind quarters are all looking more filled out. He used to look like a ewe neck, but now he is straight from withers to poll.

There's a slightly different sleep disorder called micro-sleeping - he might suffer from that.

 Here's a though.  Is the stall that they share open into the pasture?  Since these guys are coming off the track, maybe he isn't comfortable sleeping without being stalled as I'm sure he has spent most of his life.  Maybe if the stall could be closed, he would be more secure and fall into REM sleep.

If you're only seeing this behavior when the girth is being tightened, I'd doubt narcolepsy, epm, or even general fatigue as a cause. I view this particular behavior as a variety of "cold back" and believe there has to be nerve involvement. I've seen horses posture as you describe (front legs outstretched, chest dipping toward the ground) and I've seen those that will literally fall over onto their side as it temporarily paralyzed. When I come across this behavior I always recommend:

 1. Never tightening the girth in a tight aisle way (in case of a fall).

2. Tightening the girth very gradually... walking the horse a bit between holes, as you are already doing with success.

3. An appointment with a good chiropractor.