Question

I own a show horse in moderate body condition. He has access to sparse pasture 24/7, and is fed a mixed hay, a vitamin/mineral supplement, and a calming supplement (magnesium, thiamine, tryptophan). I would like for him to gain more muscle and be less nervous and spooky. Any insight?

Answer

The current vitamin and mineral supplement is not highly fortified, so key nutrients could be marginal in the diet, especially since the actual nutrient composition of forage being fed is unknown. A forage analysis can provide a more conclusive idea of the nutrients found in the hay and therefore provide a more robust diet evaluation.

Have you considered feeding a ration balancer with the hay? This type of feed provides essential amino acids, vitamins, and minerals to balance the diet and provide some additional calories. Moreover, do you have an estimate of how much hay your horse is consuming? Can you provide a better description of the hay in terms of its composition—is it mixed grass or mixed grass/alfalfa, for instance?

Magnesium and B-vitamins may help some spooky or nervous horses. Studies indicate that increasing dietary fat levels can help behavior, often in combination with reducing starch. While the current diet is already low in starch, you may consider adding a fat supplement, such as stabilized rice bran, to the diet at 0.5-1 lb (0.25-0.45 kg) per day to provide a highly digestible source of calories. This will promote muscle building as will maximizing protein quality (with a ration balancer and/or alfalfa) in the diet and thoughtful exercise.