Feeder- breeder dimorphism is advantageous when large offspring for slaughter is obtained from small breeding animals. The effect of feeder- breeder dimorphism on herd efficiency is evaluated for terminal crossbreeding and growth modification by biotechnological or dietary means. Selection criteria for breeds or lines in terminal crossbreeding can be derived from economic weights relating to herd efficiency, i.e. from the value of the percentage relative gain in herd efficiency for a given percentage relative gain in a component.
Keywords: Feeder-breeder dimorphism, herd efficiency, meat production