DSLD in a young horse

[Turntable]

Can anyone tell me if there is a definitive test for this condition that could be carried out during a PPE on a young horse? I’m looking at a lightly started 4yo that has kind of an odd- slow, floaty yet also loosey-goosey way of going behind. Like the suspension is a bit soft. Admittedly the horse is very gangly and immature and is certainly sound in any traditional sense: moves forward well, is very even and balanced, jumps beautifully, and is overall a nice, even very good, mover. But something looked odd to me so I researched other horses from the same breeder/ stallion online and I am seeing the same kind of movement there too. Other horses by the same sire seem to be showing and doing well but the oldest get are still young enough that I believe it wouldn’t be showing up as a soundness issue (6 or 7 I think).

I’m still interested in the mare but before I spring for a PPE etc I would like to pick the COTH breeders brains a bit about spotting this in the young horse. Thanks in advance!

[Libby2563]

Nothing definitive unfortunately. Even the nuchal ligament biopsy, which is so invasive that I can’t imagine it being done on a PPE, isn’t very reliable in young horses. If the vet has experience with it and some damage has already occurred they might be able to see something on extensive ultrasounds, but they certainly couldn’t rule it out.

I won’t buy anything with soft fetlocks/pasterns after having to euthanize a lovely Hanoverian at 5 years old. He went lame at 4 and DSLD was confirmed at necropsy. His nuchal biopsy was positive-ish but not totally clear. Ultrasounds and MRIs were not diagnostic for it either.

Honestly, even if it’s not indicative of DSLD, I don’t think that hyperelasticity bodes well for long-term soundness so I would stay away regardless.

[4horses]

If in doubt, stay away. DSLD is a horrible disease. It only progressively gets worse and the horse gets more and more painful. Look at sire, dam, and grandsire, granddam.

In order to avoid DSLD you should only breed older horses as it tends to show up by then. If the horse is 15 yrs old or older and sound, he probably won’t get it.

If you can find recent pictures of sire or dam, or actually go see them- then that is even better. Don’t be afraid to email people and say hi, do you have any recent pictures of Einstein… Or whatever his name is. People should be proud of their horses and not afraid to send some pictures.

Look for straightening in the hocks. Look for the fetlocks to drop during movement. Easiest to see at the walk or standstill.

[Lusoluv]

We have a young horse where I board that I thought had lowish rear pasterns and was a nice mover. Everyone else oooh and ahhhed over him. I thought he looked weird as a 2 yr old. Now he is 4.5 and lame. They are turning him out for a year without work, but IMO he’s done. Trust what you see and don’t pursue any horse with the indicators you describe.

[beowulf]

There is no PPE test. Like another poster mentioned, the only definitive is necropsy. You can do a nuchal ligament biopsy but it is incredibly invasive and is usually a last ditch effort for insurance and/or breeding reasons.

There are a few different types of DSLD/ESPA: there are horses who show clinical symptoms before the age of 8 and the prognosis for them is incredibly poor and the best route is immediate euthanasia, and then there are horses who show clinical symptoms after 10-15 – for these horses, the prognosis is a little better in the sense their pain and symptoms can be managed, until they cannot.

DSLD/ESPA is diagnosed by a combination clinical symptoms:
-age of the horse

• windpuffs or swelling in and around fetlock
• lameness history, transient forelimb lameness
• body soreness
• behavioral changes
• difficulty lying down or getting up
• loss of condition including failure to develop topline in work
• ultrasound of suspensories - should see ‘fraying’
• dropping of pasterns.

Some owners might opt to do the nuchal ligament biopsy, but as mentioned it is invasive and painful for the horse.

Some shared symptoms I have seen in DSLD/ESPA cases that are no way peer reviewed: -

• elasticity of the body and back, great movers
• loss of condition, visually ‘sunken’ topline including ‘tight’ neck and shoulder
• dropped belly
• standing camped under
• neurologic movement most noticeable at trot

I should point out that the dropping pasterns are one of the last clinical symptoms of the disease and are a symptom of failing connective tissue, so if you see this in a horse, the ESPA is already quite progressed.

Proximal Suspensory Desmitis and soft pasterns can clinically present as similar to DSLD, but DSLD/ESPA is a connective tissue disorder, in its simplest terms. The other two are injury and anatomy, in that order. Horses naturally straighten through their hocks as they age and horses born fundamentally straight through their hock can look like DSLD as they become aged. Horses who raced or had long careers in eventing or dressage can appear to have dropped pasterns as their bodies age, lose elasticity, and older injuries cause compensation.

PSD and dropped pasterns can also show in aged horses, like the above two images provided by another poster, which are of stallions that were never biopsied for DSLD/ESPA. I would be hesitant to apply any diagnosis to an aged horse especially if it appears in good condition otherwise. See: Mr P, the bay in the photos above. Mr P stood at stud until his sudden death (colic) at 29 - a horse with DSLD/ESPA would not have been able to sustain the books he did, live cover too.

I would trust your gut. If either parent are available, see how they are doing. DSLD/ESPA has a genetic component, and if offspring has it chances are someone else in the family does. The mode of inheritance is not well understood yet, and it doesn’t appear to be Mendelian the way color or WFFS inheritance can be, for example.

DSLD/ESPA does have the promising attention of several large vet schools. It appears they are working on trying to isolate the markers responsible so they can manufacturer a hair or blood test for it.

[Turntable]

Thanks all, this is good info and I think I’ll keep looking. Bummer!

I’m very familiar with the sires bloodlines and I don’t think there is any problem there, and he is actively showing and winning in the jumpers. The dam has a lot more TB and lines that I’m not as familiar with and it’s likely going to be impossible to track down many relatives on her side.

[signmypapyrus]

My last mare had ultrasounds to determine her DSLD, but a DSLD vet/specialist did it. DSLD has also been reclassified since there are more symptoms than dropped pasterns.

Stay far away from a horse with suspected DLSD. I still have nightmares going through that horrible ordeal.

[JB]

You COULD ultrasound the suspensories, but unless the disease is already present, you won’t see changes. You can get a false negative, but not a false positive.

[signmypapyrus]

I’m not a vet and certainly not an expert. I just remember that the vet who performed the radiographs looked for something specific. She did one of the first big studies on DLSD, which I’m happy to message anyone. It was actually really cool to meet her and hear her perspective. I do have the images somewhere.

I also remember that she told me that DSLD is equivalent to Ehler’s Danlos Syndrome. For example, before my mare’s pasterns began to drop, she had very strange symptoms: stretchy skin and weird “dragon” breathing. Heaves was ruled out and several other vets began to suspect DSLD because of the new diagnostic criteria. They injected Adequan and put her on Cosequin to rule out arthritis, but those didn’t help her. Previcoxx or Equioxx did help as well as correct trimming, period shoeing, bute, and very light exercise-- basically taking her on short walks. My mare also use to put her feet in holes, which is one of the tell-tale signs, too.

It’s an incredibly bizarre disease. I hated watching my girl suffer through it, mainly toward the end because new weird symptoms started to pop up and the medications stopped working. That was when I put her down.