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

Abstract

Several economic,concepts,that,in- fluence,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,de- finition 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,per- formance. 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,