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Friday, August 20, 2010

Investigation #2: Selenium

Just to be clear, my vet and I believe we are dealing with the condition of Sporadic Exertional Rhabdomyolysis, not chronic...of course that could change if we have more episodes! (God stress levels and checkbook can't take too much of this...)

Yesterday I posted what her recovery plan looked like at Tevis versus the other rides and got some hints on how that might improve that part of my management strategy. Today is a look at culprit #2: Selenium levels.

By pure luck I had blood drawn for Selenium testing last week, 5 days prior to the tye up. Results came in the day of the tye up at.....0.20ppm.

My vet feels that she is within the normal range (.008-.5ppm) and since the toxicity levels of Selenium can cause some very nasty things, that this level is healthy and recommends no supplementing.

However, I've been hearing more and more about endurance horses needing to be in the top range of the "normal" range, ideally between .25 and .3, as levels below .25 *can* be a factor/risk for tying up.

So what do I do?

Here's what I've decided. I will supplement with Selenium. every 6 months I will pull blood samples to make sure I'm not over supplementing, and I will strive to keep Farley in the .25-.30 range. It's still in the "healthy" range, and far enough below the *max* of .5 to keep me out of trouble, and I cover my a$$ if this IS a factor in the tye up.

And I'm not going to tell my vet.

Do I feel a bit guilty? Yes. I'm generally an honest person. But I think this is a battle that doesn't have to be fought. I have another guideline for Selenium from another vet and I agree with her logic. I don't want to argue with my vet about this and it's pointless - the only risk is that I *might* get over that .5 limit (which is why I'll monitor regularly) AND by getting her to the .25-.30 range, it eliminates another suspected tying up risk factor.

*sigh* sounds like justification to me. I HATE confrontation!


  1. When Phebes had her episode I asked my vet to draw blood and test for selenium and she wouldn't do it. She said it was "a waste of money." I've been somewhat p-o'd ever since. I thought, and was told by two endurance vets that I should have it checked to see if she was deficient. You have to understand that we live in rural PODUNKVILLE. But the next time she's sedated for teeth floating I do want that selenium level.

    Since this disorder is most typical with very fit horses I have a theory that it is progressive. We just notice it when it reaches critical mass. Phebe's muscle tone continues to be a concern for me. When she's had plenty of time off her muscles are soft and pliable, but when we get into regular work her topline over her rump will firm up. Her vet scores on muscle tone at rides have been B's and C's (the C scared the hell out of me). The best score we had was the ride I had very little preparation for! So my theory continues to be that progressive work somehow sets up the perfect storm for tye-up. Something at the cellular level is seriously screwed up.

  2. EG - I feel your pain. Especially in an area without many options. :(

    Farley's muscles stay "soft and pliable" all the time, so I don't think it's been an unseen issue, but I think what you described could be an issue for a horse that is more chronic - but I'm not expert so take my opinion with a grain of salt.

    I DO think it's important, once the horse is conditioned to not to TOO MUCH conditioning. I think fatigued muscles at an endurance ride can only cause problems, and may be responsible also for some of the cramping during rides (although it can also be a sign of underconditioning, so it's such a fine line!)

    during the last couple vet checks at Tevis, I did start to see "B" scores on muscle tone, but the vets said not to worry about it - she looked "typical" for how far she had gone. But now I wonder if that's where the problem started?

  3. Can you offer selenium free-choice? Then Farley can self-regulate - most of my critters are pretty good about this when it comes to salts and minerals. Speaking as someone with close connections to human health care, I would encourage you not to withhold info from Farleys' vet. it can make the difference between a wrong diagnosis/course of therapy, a right one, and one that is just plain detrimental if she needs further care for this down the road. It doesn't have to be a confrontation with your vet though - you've obviously given it a lot of thought and have some info in hand about endurance horses possibly needing more - your vet might be interested to know this and modify care accordingly - especially with new findings and a large/diverse client base, it can be hard to keep up with new trends in treating high performance animals. And you are perfectly within your rights (and Farley's best interest) to seek and use a second opinion - your vet should *expect* you to do this. I would tell him/her all the reasons that you want to supplement, including the endurance specific info and the second opinion and if he or she has any strong objections, they should either make excellent logical sense to you (personal offense doesn't count), or maybe it's time to find a new vet. You and your vet are part of Farley's *team*, not adversaries.

    (In re-reading my comment it sounds like it could come off as bossy - I really don't mean to - obviously you know your horse and your vet better than any random person on the internet and so you're the only one who really has all the info to make a decision about her treatment and how you deal with the vet. I'm just trying to suggest that talking about treatment alternatives need not be confrontational and are definitely in Farley's best interest.) Good luck!

  4. No problem about being bossy! (BTW - i didn't read the comment like that :)).

    My vet just called and decided to bring it one more time, so carefully approached it and said that I felt like it couldn't hurt ot cover one more factor that could possibly contribute AND I was willing to retest often to make sure we weren't getting into toxic levels. He said that as long as I was very conservative he was wililng to work with me! Whoohoo! I'm so relieved as I would rather have an honest and open relationship, but I try and balance that without being overbeing and a know it all.

  5. Mel - have you gotten info on what levels of Se are appropriate for endurance horses? You may want to email Susan G and ask her. I can get you her email if you'd like. Stick with the yeast Se, it is safer. It takes awhile to get the levels built up with a feed through supplement, but it is safer than giving the shots.

    The supplement I feed I feel has gone a long ways to keep my horses from getting muscle sore or stiff on rides, even when we've had to stand in the rain or whatnot at a vetcheck.

  6. Kathy S. forwarded me an e-mail from susan G. with info on the levels when Kathy's horse tyed up, which is what I'm going off of.

    I would love to chat directly (e-mail) her if you have her contact and you think she would be willing/have the time to give me advice.

    So far I'm working off the assumption that .25 is minimum, .30 is the target, and I may have to supplement beyond the label to see the levels increase to where I want them, esepcially in the 4-6 weeks post tye up. But it's all guess work to me and it would be GREAT if I could get her opinion on specifically Farley's numbers.

    Yep - I'm going with the yeast stuff. The e-mail said the platinum performance stuff was the most cost effective, so I took her word for it and bought it!


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