The purpose of this article is to review the development of breeding objectives in beef cattle breeding and the derivation of economic values. There seems to be general consensus that definition of breeding objectives should be the primary step in the design of structured breeding programs. Development of the breeding objective can be described in terms of the following phases: specification of the breeding, production and marketing system, identification of sources of income and expense in commercial herds, determination of biological traits influencing income and expense, derivation of economic values, choice of selection criteria, and estimation of phenotypic and genetic parameters. The modelling methods to derive economic weights can be divided into simulation, dynamic programming and profit functions.

The development of economic selection indices for an integrated Simmentaler production system was described. The breeding objective was defined in terms of production-, functional-and product quality traits. Criteria included in the total index were birth-and weaning weight (direct and maternal), final weight, mature cow weight, days-to-calving, backfat thickness, tenderness and marbling. The total merit index was termed as I T = -1.60 BW D -1.95 BW M + 2.23 WW D + 1.75 WW M -0.54 FW -2.01 MCW -13.21 CD + 4.97 BF -2.36 T + 12.66 M. The correlation between this index and the aggregate breeding objective was 0.988. The economic superiority of the progeny from the top 40% of animals selected on their ranking in the total index, relative to the average progeny, is expected to be R 119.51.

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