For example, hydrated lime, which is caustic, can cause problems for mature horses and is very risky with foals. The substance can burn the soft part of a horse's hoof, and lime dust poses difficulty for the horse's respiratory system and eyes. One either sprays or sprinkles the ammonia-absorbing products on the stall floor, concentrating especially on the wet areas. Besides better smells, you'll enjoy the added benefit of lessening the fly population in the barn and adjacent areas by creating an inhospitable environment for insect egg-laying and maggot growth. When it gets cold, the temptation is to keep your horse barn as airtight as possible to keep your horses cozy.
Proper ventilation keeps healthy, fresh air moving in the barn to remove odors and stale air.
Use common sense. If you have stall windows, open them. If you have doors, open them. Strive for cross-ventilation. Fresh air has never hurt a horse, but dusty, stale air can.