Feed for their cattle is by far one of the largest expenses for dairy producer whether it be provided by the land they graze or crops grown or purchased. Pasture based dairy producers invest much time and effort into maintaining their pastures and thus feed for their cattle. Pasture management techniques such as rotational grazing are common for dairy production. Many large dairies that deliver food to their cattle have a dedicated nutritionist who is responsible for formulating diets with animal health, milk production, and cost efficiency in mind. For maximum productivity diets must be formulated differently depending on the growth rate, milk production, and reproductive status of each animal.