I had this "confusion" too. Here I thought it was something "cow" related and special that was included with cottage living because I do not own horse ranch but I do own the cottage living. It does show up when interacting with the Animal shed itself and the animals belonging to the shed, but no other mention of it in game other then the shed and it's animal feeding interaction options. I was trying to figure out where and how to find this special hay to put in my inventory to feed my cows. At 1st I thought maybe it was something I had to grow so I was looking for seeds in town, then even debug menus to see if the item even existed in game.
