Horses are animals in Harvest Moon: Tree of Tranquility that you're able to interact with. They're obtainable after Brownie Ranch is unlocked and upgraded once through shipping farm products (milk, eggs, etc.), however you'll need to make sure you have a barn to put them in. When you buy them, they start off as colts. They take 28 days to mature. Once your horse is mature, you will be able to ride it. It is one of the two animals you can use to ride around the island. You can ride your horse from inside and outside the barn, though it obviously can not go into any other buildings in the game.
Purchased From: 6300G at Brownie Ranch.
Colors: Red, Black, Brown and White.
Lifespan: Around 4 Years.
Reproduction: They're able to be impregnated using a Miracle Potion.
Happiness: Increased by being talked to, brushed, hand-fed, and let outside on sunny days.
Products: Horses do not have any other purpose except for providing quick transportation.
To increase the speed at which your horses run, raise their heart level. They can be ridden while pregnant.
Riding: To ride your horse, you need to purchase a Saddle from Brownie Ranch (1600G). Approach your horse and put the saddle on it. You will automatically get on your horse. To get off, simply press the B button on your remote (OR you can Press A then B to whistle, and you will automatically be on your horse (you don't have to be near your horse)).
(Hint): You can call for them when you need to get somewhere, and you don't have your horse with you, by pressing the A button and the B button twice.