http://www.equisearch.com/horses_care/help-your-horse-grow-a-thick-winter-coat/
So dependant on how cold/warm it is, it can slow down or speed up the coats growth, and you can control how long the coat grows by how much light your horse gets over 24 hours a day.
So dependant on how cold/warm it is, it can slow down or speed up the coats growth, and you can control how long the coat grows by how much light your horse gets over 24 hours a day.