Our turkeys are purchased as day old poults from certified disease free  hatcheries.  Once they arrive, we put them into our turkey nursery where they are kept warm and safe for several weeks, then moved to an outdoor pasture. 
The large outdoor fenced area is covered with green grass and lush vegetation which gives them shade from the summer sun, and protection from overhead predators until they are bigger. As the season progresses, they consume all the vegetation in the pasture.