A data processing system and method are provided in the form of a livestock management system for specifically managing feeding tasks for a group of animals within a designated location. The system and method incorporate a data processing function wherein comprehensive data is gathered and maintained on individual feed rations which are selectively used to feed a selected group of animals. Functionality of the management system and method include the ability to track amounts of ingredients used for each type of feed ration and any excess or surplus ingredients which may have been withdrawn from storage locations. The management system and method results in improved commodity inventory control to prevent waste of ingredients and to prevent potential cross contamination between different types of feed ration.