Economic Definition of Total Performance, Breeding Goals, and Breeding Values for Dairy Cattle,

Abstract Several economic concepts that influence definition of economic merit are discussed. A profit equation including fixed and variable costs, an aggregate genotype including important lifetime traits, and a selection index are used in a hierarchical approach to economic definition of total performance, breeding goals, and breeding values. A composite profit equation includes milk sold, calf value, ending inventory value, initial inventory value, feed cost, facilities cost, labor cost, veterinary cost, insemination cost, and individual cow care costs. Variation in the numerous studies with profit equations is mainly in method of estimation and completeness of items. Progress has been less in quantifying economic breeding goals and criteria for selection than in defining total performance. Economic importance of traits is discussed. Comprehensive selection goals reflect profit per day of herd life. An index includes milk and constituent yields, cell count, beginning and ending weight, calving interval, age at first calving, conformation, and calving difficulty score. Milk yield will continue to be the major trait for selection. Other traits will need to be added to the selection criteria to improve genetic gains for total economic merit based on their availability and on specific economic and environmental conditions.