A. I have never known a horse to breathe any differently in even severe cold than at more moderate temperatures, though I have known many horses whose breathing became more labored when exposed to dust. Many horses have allergic-type reactions to dust, and these reactions may eventually develop into heaves. Though there are medications and treatments which can offer some relief to heavey horses (you could discuss this with the vet next time he comes out), the best and most effective option is proper management. That means creating as dust-free a living environment for your horse as possible. Many horses with dust problems are much more comfortable living outdoors than in a confined and typically dusty interior stall. If such a horse needs to be stalled, one should use as low-dust a bedding material as possible. Keeping cobwebs swept out of the barn and removing the sensitive horse from the barn during cleaning and sweeping will help prevent his dust reactions. Certainly check his hay for dust. Remember, he has to put his nose right into the hay to eat. In order to check the hay’s dust content, you should do the same. Take a flake, bury your nose in it, and take several deep breaths. Does it make you cough? If it does, it probably isn’t doing your horse a lot of good, either! If your hay is only mildly dusty, dampening it should take care of the problem. Of course, if the hay is moldy, it shouldn’t be fed at all. If you question the quality of the hay available at your stable, you might consider feeding your horse hay cubes or a complete pelleted feed instead.

Unless your horse’s hooves are currently very shelly, crack easily, or have some other affliction or inherent weakness, I wouldn’t bother with the expense of biotin supplements. I suppose I wouldn’t bother with the shark cartilage either until I knew exactly what I was dealing with regarding this horse’s legs. I don’t know exactly what minerals are involved in shark cartilage, but I do know there are certain minerals that can have truly devastating effects on the equine body if fed in excess. I prefer to feed a well-balanced diet of good quality grass hay and 12% protein sweet feed to my mature horses. I only very rarely find sufficient cause to add supplements. They are expensive, and they have the potential to cause more problems than they cure if one is not very knowledgeable about the total dietary mineral and vitamin amounts required and provided.