There isn't much you can do to stop a horse from coming into season. This is a natural occurrence.
winter
Winter I should imagine.
winter and fall but mostly winter
The answer is pretty simple... WINTER!Winter
winter
autumn-winter time
Winter
It is not common, but it is quite possible.
You should cover a horse in WINTER
I think in the Winter.
late autumn/winter
When they are sweaty and in the Autumn and winter