Boomer, Excess Energy or Selenium Deficiency

The last two times Boomer was used for lessons he was acting spooky. Both riders learned a lot working him through it which was great but this is not his normal temperament.  I thought something must be bothering him.   He seemed a little touchy in the back which is a common symptom of low selenium.  I would expect, knowing him, that he would get quieter, more lethargic if his selenium was low but there's no rhyme or reason to the symptoms of low selenium.  I've seen horses buck, rear, bolt, be over-sensitive, be lethargic, overly quiet, be lame in one leg in the morning, then a different one later, touchy to brush...

I've had a horse of my own and a horse raised by a vet who had both been on selenium their whole lives and yet came up deficient as training progressed.  Different horses use selenium at different rates  and some don't use the more common inorganic selenium as well as the organic selenium.  There are also still vets that don't recognize it as a problem but I'm seeing it more and more.

At the other end of the spectrum, selenium toxicity can be fatal.  Some parts of the country have selenium in the soil but here in the pacific northwest we have a deficiency in the feed.  Selenium supplements in feed and available at feed stores are in some cases adequate for maintenance but will not bring selenium levels up to where they need to be.  You need a blood test from your vet and a supplement they sell. I prefer Platinum Performance Selenium Yeast available in the US but only through a vet here in Canada.  If it's not what your vet uses they can still order it.  The blood test is to make sure you don't overdose and kill your horse.

Boomer was on supplemental selenium but has been off it for two months.  Some horses just need their levels brought up and can then maintain on a regular mineral mix, others need to stay on it.  I rode Boomer myself today, I let him do lots of cantering and worked him more than what he gets in lessons.  I also am more balanced than his students so that would have been more comfortable for him.  He tried really hard and was a good boy but I will put him back on his extra selenium and see if the touchiness in his back goes away.

The other possibility, and I see this a lot as well with horses coming in for training,  not enough exercise for their calorie intake.  Although he has a pasture and a buddy to play with his lessons have been pretty quiet work.  He turns six this year and I noticed as a five year old he had a lot more energy than when he was four. I suspect due to the fact that he's done growing. It's common for people to have a horse started at 2 or 3 (and they should be) who's nice and quiet and then some time in or after their 4 year old year they become unmanageable and need to go to a trainer.  Although there hasn't been a feed change the horse now has excess nutrients available for 'play' because he's done growing.  When I got on Boomer I only walked him 50 feet then asked him to canter and let him for as long as he wanted.  He was enjoying himself and I need lots of canter work myself before I go to Al Dunnings. Then we worked on a few collected transitions with standing in between while I taught.  He wasn't spooky at all and he wasn't spooky the last two lessons, after they had ridden for awhile. Excess energy can also be a major cause of training problems.

Most of the horses, and definitely all the "problem" horses that I've had in training have tested Selenium deficient.  If something changes in your horses personality or training, consider pain to be a prime suspect.  It's worth it to have blood drawn and check mineral levels and rule out deficiencies before assuming it's a training problem.