Too much selenium?

[lintesia]

First off – I’m having blood work done tomorrow which will include the Selenium and Vitamin E levels.

What are the signs of too much selenium in the diet? I recently noticed that the quality of the my horse’s hoof walls has changed and it appears to correlate with when I bought him. He does not get a selenium supplement but there is selenium in his vit/mineral supplement CA Trace. He gets orchard grass hay which has not been tested but come from a supplier my trainer has used for many years. I found an article by Rood and Riddle showing photos of poor hoof quality and there is one that is similar to what I’m seeing on my guy: https://www.roodandriddle.com/assets…Y_AJF_0917.pdf – Figure 5, except my horse is not quite as dramatic. The article states too much selenium as the cause.

I know that too much selenium can be toxic and have serious consequences. It’s been off my radar since with the exception of CA Trace I have never added selenium to the diet, and I’ve used CA Trace without problems for over 10 years.

Has any one dealt with this? Were there other side effects? Were they reversible once the diet was changed?

Thanks COTH!

[Obsidian_Fire]

When did you buy him? What else in his diet has added selenium, besides the CA Trace?
Honestly I’d wait for blood test to come back before panicking.

[Posting_Trot]

In some areas of the U.S. there are plants that store selenium, often at high levels. Then, if horses eat them consistently as part of their diet, horses can essentially be poisoned by selenium. I’m linking to a map of selenium levels on a statewide basis, but you should know that soil levels can vary substantially locally.

https://drkhorsesense.wordpress.com/2014/10/09/selenium-paranoia/

I’ve known of one horse (in Mass.) that suffered from selenium toxicity: she’d been eating moss at her previous barn (apparently) that stored the selenium. She was treated by the vet, and has been totally fine. Before she was diagnosed, she seemed to have the “blind staggers” associated with selenium poisoning, so she was pretty badly off.

Here’s more from Dr. Kellon (a well-known vet) on the issue:

https://drkhorsesense.wordpress.com/2015/09/17/selenium-paranoia-2/

[candyappy]

What else is he eating? If he is on a bagged feed that supplies the selenium he needs he may be getting too much. OR it could be due to his living conditions and the quality of his stall, paddock or pasture. If he is in mud or wet conditions constantly, or in a wet stall etc… all that can really cause a good foot to go bad.
Extreme foot changes are also related to farrier’s as well.

Evaluate not only his diet but living conditions and your farrier.

[Simkie]

Can you share some pics of your horse’s feet? Figure 5 on that document shows (I think) a hoof capsule that’s sloughing off, which does happen with selenium poisoning. But in trying to think what might look kinda like that, just less severe, all I can come up with is an abscess that’s blown out at the coronary band, and is growing out…and that would not be indicative of selenium toxicity.

Selenium overdose is really pretty rare, particularly outside of the geographic region where selenium is noted as high. It’s great that you’re having him tested, and it will certainly give you more info.

I do have a horse that abscesses a LOT in the winter, and finally figured out that she needs more copper and zinc. We kept her well covered this winter and she was mucho improved…and a LOT of areas of the country have conditions that can lead to a need for more copper and zinc in the diet. Deficiencies of those absolutely contribute to poor hoof growth (which is why you often see copper and zinc in hoof supplements), so if your selenium test is normal, it might be worth taking a look at the overall diet for Fe/Cu/Zn/Mg balance and adding some copper and zinc to see if that helps any.

[lintesia]

I’ll try to address everyone’s questions!

I’ve had this horse for about nine months and the changes in hoof wall quality seems to correspond to that. The changes can be seen all four feet. I talked it over with my vet today and he is not concerned based on what he sees and the otherwise fabulous condition of the horse. Nonetheless, he drew blood and it will be tested for both Selenium and Vitamin E.

This horse is fed primarily orchard grass hay. Our turn outs are dry lot – no grazing. In addition, he gets a scant scoop of TC Senior, Elevate Vitamin E, Cosequin ASU, CA Trace, Hoof-thrive (a pretty basic hoof supplement that I’ve seen good results with), Total, Calm and Focus, and TC Omega Oil Blend. He’s an easy keeper and is up-to-date on everything.

I’ll try to get some pictures. And, based on the results from the blood work, I might have his diet analyzed by an equine nutritionist (Summit Equine). I try to make my supplement choices based on need rather than getting sucked into advertising promises, but I am concerned the diet I’ve put together for him is somehow unbalanced.

I appreciate all of the interest and advice!

[kashmere]

Looking at Fig. 5 - I am wondering whether you are actually just seeing a tighter laminar connection growing down from the coronary band. Depending on what his diet was before you got him, the switch to mainly forage and a very good mineral supplement like Cal Trace could very well mean you are growing in a stronger, better connected hoof. Diets that are imbalanced, lacking critical minerals, and - huuuge contributor - are high in sugar, very often result in wholesale poor laminar connection. I’ll try to find a picture of my guy who is about halfway through growing in a better connected hoof - seeing the old growth move down the hoof capsule can look relatively dramatic!

[Rosewatt]

@lintesia

I’ll try to address everyone’s questions!

I’ve had this horse for about nine months and the changes in hoof wall quality seems to correspond to that. The changes can be seen all four feet. I talked it over with my vet today and he is not concerned based on what he sees and the otherwise fabulous condition of the horse. Nonetheless, he drew blood and it will be tested for both Selenium and Vitamin E.

This horse is fed primarily orchard grass hay. Our turn outs are dry lot – no grazing. In addition, he gets a scant scoop of TC Senior, Elevate Vitamin E, Cosequin ASU, CA Trace, Hoof-thrive (a pretty basic hoof supplement that I’ve seen good results with), Total, Calm and Focus, and TC Omega Oil Blend. He’s an easy keeper and is up-to-date on everything.

I’ll try to get some pictures. And, based on the results from the blood work, I might have his diet analyzed by an equine nutritionist (Summit Equine). I try to make my supplement choices based on need rather than getting sucked into advertising promises, but I am concerned the diet I’ve put together for him is somehow unbalanced.

I appreciate all of the interest and advice!

How much in lbs or some other measurement does he get of the TC senior and CA trace? Is this the hoof thrive? https://equithrive.com/products/equi…=7423364825111

Depending on the quantity, I’m seeing that each of the above all has Cu, Zn and Fe in them and they could be out of balance, accordingly. These 3 interact with each other, so a imbalance in one can cause another to be of little efficiency. With known measurements, you could attempt to calculate an estimate of these minerals and Se your horse is getting through concentrates while you are waiting for the test results to come back. But, I also agree with kashmere that tighter white line connection can possibly look like a less extreme example of fig. 5 by the bump it would create.

That being said, I think the blood test is helpful either way and you can never go wrong with taking a second look at nutrition with a professional - a good learning opportunity to take advantage of.

[kashmere]

Since he is getting Cal Trace, I would personally give the Hoof Thrive a miss - it is at best not going to be adding much on top of the CAT and at worst the added iron will be messing up the ratios in the CAT and therefore potentially interfering with his ability to properly absorb Cu and Zn.

TC Senior does have added Se - though at max 1.0ppm it’s unlikely to tip the scales but one never knows.

In your shoes, I think what I would do is ditch the TC Senior and the Hoof Thrive in favour of upgrading to the Cal Trace Plus and soaked molasses-free beet pulp to carry the supplements.

[JB]

The Hoof Thrive is adding a whole 6mg Fe, and in the context of probably 500-1000mg from just the forage, is nothing. Besides, it’s bringing more zn and cu than fe, so if anything, is helping the ratios. But it’s nothing to write home about either. If you’re feeding a full ounce, then half the biotin is wasted. If you feed 1/2oz to manage that, then the cu/zn/fe is not worthwhile, and the amino acids aren’t useful either way.

[lintesia]

@JB

The Hoof Thrive is adding a whole 6mg Fe, and in the context of probably 500-1000mg from just the forage, is nothing. Besides, it’s bringing more zn and cu than fe, so if anything, is helping the ratios. But it’s nothing to write home about either. If you’re feeding a full ounce, then half the biotin is wasted. If you feed 1/2oz to manage that, then the cu/zn/fe is not worthwhile, and the amino acids aren’t useful either way.

So, are you suggesting that while the Hoof Thrive is not doing harm, it’s not actually doing what it’s supposed to do either? I’m not beholden to it – I just want to do right by my horse!

[JB]

IMHO, there are far better hoof supplements out there. I can’t see the probiotic amounts, and can’t find the product online to see. But the other nutrients are all but useless in their amounts, other than the biotin and mayyyyybe the B6. What made you decide you needed a hoof supplement, and what caught your eye about this one?

[Rosewatt]

Just did some calculations ( someone check my math in case I made an error):

TC senior :

• Copper: 50 mg/kg x 1 kg/ 2.2 lbs x 1.5 lbs = 34 mg Cu
• Zinc: 200 mg/kg x 1/ 2.2 kg = 90.9 mg x 1.5 lbs = 136.4 mg of Zn per 1.5 lbs
• Iron: 175 mg/ kg on bag to 119.3 mg Fe per 1.5 lbs
• Selenium: max stated to be 1 mg/kg, so per 1.5 lbs = 0.68 mg Se

CA Trace:

• Copper: 175mg/kg
• Zn: 500 mg/kg
• Fe: 0
• Selenium: 2 mg/kg

Hoof Thrive:

• Copper: 20 mg
  -Zinc: 82 mg
  -Iron: 6 mg

So, Selenium (2.68 mg) with these three is below the suggested tolerable level (>5 mg per day), as long as numbers are similar to the values stated on the bag. Your horse could be getting extra selenium elsewhere. Do you know if your area is high in selenium levels?

Total Cu, Zn, Mag and Fe from the above is:

Copper: 229 mg Cu
Zinc: 718.4 mg Zn
Iron: 125.3 mg Fe
Manganese: 68 mg/ kg

Ratio (rounding) 2 Cu: 6 Zn: 1 Fe. Recommended ratio is around 1 Cu: 4 Zn: 4 Fe or 1:3:3. Your copper to Zn is about a 1:3 ratio.
To Maganese: 3 Cu: 11 Zn: 2 Fe: 1 Mn

For feed, your within the tolerable amounts of these minerals, but hay/ grass could tip over the scale and cause some imbalances. Iron here is on the low end (should be relatively even with Zn) BUT iron is often high in many environments, so nutritional deficiency is rare. I wouldn’t change anything on this unless blood tests come back and vet suggests to do so.

I agree with JB that hoofthrive isn’t doing much harm. 6 mg of Fe is very little in contribution compared to the copper and zinc it provides. Simplifying things to one complete vitamin/mineral supplement or feed could be easier for you though, but I’d wait for the blood test results before making changes as it will give you something to go off of. I’d also recommend testing hay too, if at all possible, then your equine nutritionist will have a better picture of what is needed.

[JB]

Math = :yes:

Unless you’re in an area where soil is really high in Se, it’s highly unlikely you’re dealing with an Se toxicity.

We’d really need to see the actual feet. “Fever rings”, aka any change in diet/footing/turnout/exercise/illness/injury can cause these which can look like that Fig 5, but not actually be cracks. If they ARE actually cracks, then it’s a concern for sure. But I’m guessing they are these rings which correlate to a dietary change, stress of moving, maybe even change in movement (amount, footing, etc) when yo got him.

[angelssix]

@lintesia

Update: I’ve had blood drawn for Trace Eements, Selenium, and Vitamin E. I won’t have results until sometime next week.

Rosewatt – Wow! I can’t believe you did all that work. Thank you!
JB – Hoof Thrive is made by Traileze, a California company that mostly serves the racetrack industry. It’s what I’ve used (since about 20 years ago) when my farrier has suggested a hoof supplement wouldn’t hurt, and I usually see a spurt of healthy growth. But as I said, I’m not beholden to it. In fact, I didn’t include it when I made up this week’s batch of supplement baggies.

Here are some photos (and yes, this horse has mismatched front feet which are being managed by my farrier and vet):

Your horse’s feet are not merely mismatched, they are really upright.

[lintesia]

@angelssix

Your horse’s feet are not merely mismatched, they are really upright.

The right front has a low heel which makes the left front look more upright than it is. A side angle would show this better but I was taking the picture to show the hoof wall quality not his hoof conformation. His less-than-ideal hoof conformation is handled by my farrier in conjunction with my vet to keep him balanced. I would like to keep this discussion about the hoof wall quality and any dietary imbalance, please.

[Obsidian_Fire]

Honestly I don’t see a “bad” hoof wall. What I see is when you get about 2/3 the way down the hoof (approx level of nails) it wants to run forward at the toe, which is where you are seeing the ‘dip’ or whatever you want to call it. You say your farrier and vet are on top of it, so good enough.

Regarding nutrition - JB is your go-to for these things. What I have used in conjunction with a top quality hoof supplement is ground flax. That, plus green grass and good quality hay, seem to do the trick for mine.

Oh, and UltraCruz Vitamin E is MUCH cheaper than Elevate, even feeding at a higher dosage.

It takes a solid year for a hoof to grow out. So I like to watch the hoof from the coronet band down, to see if I’m affecting a change via feed. Look at the upper inch, does it look improved from when you got him? Then likely your feed is okay.

[lintesia]

@Obsidian Fire

Honestly I don’t see a “bad” hoof wall. What I see is when you get about 2/3 the way down the hoof (approx level of nails) it wants to run forward at the toe, which is where you are seeing the ‘dip’ or whatever you want to call it. You say your farrier and vet are on top of it, so good enough.

Regarding nutrition - JB is your go-to for these things. What I have used in conjunction with a top quality hoof supplement is ground flax. That, plus green grass and good quality hay, seem to do the trick for mine.

Oh, and UltraCruz Vitamin E is MUCH cheaper than Elevate, even feeding at a higher dosage.

It takes a solid year for a hoof to grow out. So I like to watch the hoof from the coronet band down, to see if I’m affecting a change via feed. Look at the upper inch, does it look improved from when you got him? Then likely your feed is okay.

I see the change in quality about 2/3 - 3/4 of the way down, which corresponds to when I bought the horse. It’s not a dip, more a change from a smooth texture to a rougher texture with vertical lines. My farrier is not concerned, nor is my vet… just me. Sigh.

I’m thrilled that JB chimed in because I always learn from her when she comments on other threads. And I’ll look into your recommendation for UltraCruz. Green grass, unfortunately, is rarely available in my neck of the woods.

I’ve also decided to enlist the help of an equine nutritionist, as my wee bit of knowledge is clearly not enough!

[Obsidian_Fire]

Make sure you choose someone not affiliated with a feed company. You want someone neutral.

[lintesia]

@Obsidian Fire

Make sure you choose someone not affiliated with a feed company. You want someone neutral.

You’re absolutely right! The person I plan to use has been up-front in answering my questions about any such relationship, and I tend to be skeptical about advertising promises. While I don’t have a lifetime of owning horses, I’ve had four and have always devised the feed program. This is the first time I’ve had such concerns and, as I mentioned in a previous post, my farrier and vet don’t share my concerns. Neither does my trainer, who has always respected my feed choices. At this point, I’m more curious than concerned and want a professional’s help in putting together all the pieces. I’ll certainly come back and share what I learn from her, although it will be at least 1 - 2 weeks down the road.