Join Date: Aug 2009
Location: secret mountain valley
If this is a sudden change, the first step would be to check his teeth. You should also have a fecal examination to determine if he needs deworming, and if so what kind. Lastly, I agree with the above, an arabian at 14 should not be dropping weight if he is getting enough quality forage (2-4% of his body weight per day, depending on his work load).
When a horse of 14 starts to drop weight, it is likely an underlying health problem (teeth, parasites, etc.) or not enough groceries, not just normal aging so please have him evaluated by a veterinarian- it will save you money in the long run instead of throwing expensive feeds and suppliments at him!