All kinds of animal feed can be bought at the animal feed buying station.
As a building I used the Giants hay store and colored it red.
The prices for the animal feed are reduced.
The mods have done their job successfully in my Build and Let's Play videos. I've also tried hard to make everything work, but I can't guarantee it. Use at your own risk :-)
Note: The building does not level automatically. So you have to level the terrain beforehand.

The following types of animal feed can be bought here:
straw
grass
hay
silage
TMR total mixed ration
wheat
barley
oats
Pig feed
Corn
Sunflower seeds
Soybeans
Rapeseed
Potatoes
Sugar beet