Has anyone heard of Equine Desmitis (DSLD)?  Had to put my 21 year old mare down yesterday.  She had been lame for approx. 2 weeks.  Had one vet/chiropractor out last Monday as we thought she was out in her hip area.  She was placed on Previcox to try and get her more comfortable as it was thought that they discomfort maybe coming from her age.  This was not helping so I had another vet come out and look at her.  This vet right away diagnosed her with Desmitis.  Have never heard of this and it has me wondering what others have experienced and heard of with this diagnosis.  Vet says that this is not hereditary however any research I have done it is saying as being potentially hereditary.  We have a foal from her so we are hoping this is not something that could plague our other mare.  Just heard broke about loosing Peach. 

Thoughts please!  Thanks!

I'm sorry for your loss. Never heard of it. Off to Google.

First let me say that I'm sorry for your loss.

I had to put one down for this at the end of 2019.  He had a spur on his ankle, and with the breakdown of the tendons and ligaments from the DSLD we could no longer keep him comfortable even on Previcox.

They are still unclear as to a genetic component.  There is just not a whole lot of research on this.  It does seem to me that a disorder of laying down proteins wrong (over simplification but you get what I'm saying) could most certainly be a genetic trait.  Because it takes so long to develop there's no real way to say something else caused it.

Several horses related to mine have had tendon issues which could entirely be a coincidence.

One of the horses I have now is related to the one I put down, so I'm not entirely erasing it from my mind.

All of that being said, it does seem to be diagnosed a lot more these days.... jury is still out on if it's the new buzz diagnosis.... somewhat of a cop out diagnosis unless it is confirmed by the nuchal ligament test.

We have a 19 yr old mare that will be put down after she weans the foal she is carring now.  It came on fast, matter of 2 months.  She is mangaing now that the weather is warming, we had some cold snaps that you could tell she was very uncomfortable but was also the early stages.  She's worse in one leg then the other and being bred options were limited.

I've seen a few with it over the years.  Arabs, QH, my parents had Peruvian Pasos who are known for it.  I dont know how much research has been done if it's hereditary or not.  Most cases seem to be injury related, that I've known.   Our mare was fine until we weaned her now yearling, she's turned out to pasture 24/7 so hard to say if she did something to aggrivate the ligaments.

Nice to know there is a name for it.  I always thought it was a conformation flaw known as coon footed.  I wish I had read this 2 weeks ago, I could have sounded smart.  I was helping a friend horse shop at a sale and we saw one, I told her it was coon footed.  She wanted me to explain, I just said you don't want him.

So sorry you lost your mare.

I have a mare who was diagnosed with chronic suspensory desmitis last year. I retired her and she's now a broodmare. 

Yeah its a sad ordeal.  

Unclear on the genetic component but like previously said pasos are over represented so its suspicious there is something heritable about it. 

DSLD (degenerative suspensory ligament disease) is different from the regular suspensory injuries horses can get, most common proximal suspensory desmitis.  Usually more than one limb is affected and you'll notice that distinct fetlock drop and straightening of the hocks thats classic for suspensory apparatus failure. I've seen it more often in the back end than the front end but it can happen to any of them. And there's not much to stopping it. 

Dr. Ellenor Kellon has done a lot of research on DSLD, she has yahoo group dedicated to it and is accessible if you have questions, need a supplement protocol, and/or want to participate in a study. 

It is not a new disease or a 'trendy' diagnosis but if I had to guess as to why the increase in the number of cases my guess would be attributed to the high iron levels in hay/pasture/feeds/water and the deficiency of copper/zinc. The copper and zinc levels in all the forage tests I have performed the past few years have been severely deficient and the iron content is extremely high. For anyone that doesn't know, iron, copper, zinc, and manganese all compete with each other for absorption. When balancing diets the ideal ratio of iron to copper is 4:1 (or less), the ratio for copper to zinc to manganese is 1:3:1.5 (manganese should be 1.5x the NRC guideline or 50% of the zinc amount but never higher than zinc). 

Copper is crucial to ligament/tendon health, as well as MANY other roles including how the thyroid/adrenal glands function. Metabolic disease is another red flag/contributing factor to DSLD. Here is some of Dr. Kellon's words on copper:

Lysine is also the source of hydroxylysine, an amino acid which is only found in collagen. Studies have shown that dietary hydroxylysine is not used to make collagen; only hydroxylysine freshly synthesized from lysine. The enzyme responsible for the conversion of lysine to hydoxylysine is lysyl hydrolase. Another key enzyme, which creates the reinforcing cross-links in tendon and ligament structure, is lysyl oxidase. Copper is a required cofactor for both.³ Copper deficiency interferes with the activation of the two lysl enzymes.⁴

Copper is one of the most common deficiencies in equine diets and an important ingredient for tendon and ligament support. In addition to low dietary levels, bioavailability is compromised by high levels of iron. Iron competes with copper for absorption. Sulfates in water may cause problems because they bind copper and cause it to precipitate out.

Many horse owners think they need to supplement iron to horses (think 'blood builders') but actually they are likely causing more harm than good - true anemia in the horse is EXTREMELY rare but relative anemia caused by deficiencies in supportive nutrients is more common. A simple blood test is not a true representation of the iron levels, the ferritin levels have to be measured and currently only Kansas State University can do this test. 

A feed tag or guaranteed analysis isn't going to give the true amount of iron a feed/supplement has, if it is included at all then the number printed is just what is 'added'. Unfortunately, iron is in most feed stuffs (for example, alfalfa and beet pulp are high) and some nutrient ingredients can be major contributors to the iron content in a product, such as: magnesium oxide, mono/di-calcium phosphate (which can be upwards of 20,000ppm iron), etc.

The highest amount of copper that I have seen in 3+ years of hay testing for me and my clients/friends is 4mg per lb - an amount that won't even meet the NRC requirement (which is a LOW number) when fed at the amount that meets the DE requirement. The closest ratio between iron and copper that I've had on a test was 10:1 but that was an outlier - the majority were 30+:1. 

Just wanted to share a bit of this knowledge with this forum. Dr. Kellon offers some great nutrition courses that I strongly suggest all horse owners take. Your horses and your bank account will thank you for it.

Unfortunately, those of you who have mares with symptoms after pregnancy are likely seeing the aftermath of pregnancy/lactation depleting the mare's body of it's minerals to provide for the fetus/foal. 

If anyone is interested in Dr. Kellon's protocol, message me your email and I will send it to you.  :)

Maybe a possibility but our mares have free choice loose mineral/vitamin as well as high quality hay if not on pasture.

The filly she weaned is a big girl but she is worse in one hind then the other which makes me think more injury.

The attached photos are from the end of August, just a couple short months before we started seeing changes.

Free choice minerals, mineral blocks and himalayan salt rocks are typically loaded with iron - it is what makes them have the red color. They will never be able to make up deficiencies in pasture/forage using loose minerals or blocks. You may be able to test your pasture/forage and have a mineral blend formulated but any commercially available product will not balance correctly. Unfortunately, 'high quality hay' doesn't mean that it is minerally balanced.

An injury can definitely make DSLD much more noticable but the DSLD has been there and her body can't repair the damage.

Has your mare been tested for Cushings/metabolic disease -- a large percentage of horses with DSLD also have Cushings so even if she doesn't have any other obvious symptoms, I would test for that (if you haven't) before you put her down just so you know for any offspring that she produced.

Do you have any pictures of the foal right after or shortly after birth? And do you have pictures from August that show her rear pasterns?