It is difficult to talk about the "natural" management of horses in a stable or in any environment that is not in itself natural for a horse. Stables, fences are already something that does not fully reflect the natural life of these animals.
That said we can try to make the life and management of our horses in the stable as close as possible to the natural. In our Ranch this is what we pursue on a daily basis.
First of all, even if taken for granted, to make a horse serene and satisfied, we try to provide him hay of excellent quality 24 hours a day. Low / medium quality hay is to be avoided absolutely in order not to have repercussions on a physical and psychic level. Food aside, at the Ranch we have a stable with 6 boxes and 7 outside paddocks therefore the horses that are in the boxes go out daily in the paddocks for at least 4-5 hours a day if not for the whole day (or all night) , also depending on the season.
The first requirement for good management must be to keep horses out in the open air in a space that allows them to move freely at walk, trot and even gallop to oxygenate the tissues and organs, see natural landscapes and other horses. We also try, as far as possible, to make the horses socialize with each other, putting them in pairs in the paddocks or even in three, so that they can be together, in company. It is clear that for this type of socialization in close contact, an indispensable requirement is that the horses are barefoot on the hindquarters to avoid serious injuries due to kicks or quarrels.
We try to keep males and females separate to avoid too much stress, especially in the moment of the heat of females, since, even with castrated males, they can cause reactions, calls, emotional stress. In the wild, a herd of horses usually has only one stallion leading the herd with all the mares and foals, while usually the males (grown or even adult foals) separate. The separated males create a "herd" of their own until they find a new herd in which to settle. These and many others are the precautions and principles that we adopt in our Ranch to make the life of our friends as peaceful and natural as possible. As Pat Parelli says "Keep it natural !!"