What can cause energy loss in horses?

Question
I have a 10 year old 16.3 hand Dutch warmblood gelding. He is a Competitive Jumper horse and is currently jumping 3'9"-4". He gets ridden everyday, except Monday which is his day off and jumps 2-3 times a week. He is on 4 flakes of timothy, 2 flakes alfalfa a day with pasture grass when turned out for 1-2 hours a day. He also eats about 3.5 lbs of Omolene 100 grain a day along with a joint supplement. He is UTD on all shots, worming, teeth, etc. The only thing is recently (Last 6 months) he has been losing energy like crazy. He is still happy and jumps great, but he has NO energy just getting him to trot or canter around the arena is a challenge let alone try to gallop to a fence. He just seems so lethargic. Some one did mention that he could have Hypothyroidism and that that causes energy loss. But the weird thing is he still has his appetite, never has a fever, and acts totally normal except the fact of NO energy!!!! Can you please help me as to what can cause a healthy horse to have no energy and be so lethargic???
Thanks

Answer
Dear Chantal,

This is certainly puzzling.  How long have you been riding the horse?  The person who mention issues with thyroid could be onto something.  This is easily tested by having your vet take a blood sample.  His diet looks like it should be fine and you say he is still happy in his work so I doubt it is diet. but it could be.  The only way for sure is to do a detailed analysis.  I would certainly have the vet out and do a full blood work up.  It may be thyroid or you may find that some of his white blood cell levels suggest that he may have something like low grade allergies that might make him lethargic.  Another option is dehydration and that will also be visible on blood work.  There could be a number of low grade things going on where he looks fine on the outside but just isn't 100% and therefore is low on energy.

I'm sorry I can't be more help.  I hope your vet may have some more suggestions.

Clair

Clair Thunes, PhD
Independent nutritionist
Equilibrate Equine Consulting,
info@equilibrateequine.com
www.equilibrateequine.com