Abstract
Groups of sibs, sisters to bulls being bred for progeny testing, can be produced by multiple ovulation and embryo transfer (MOET). Sib tests are complete at 3 yr of age, and progeny tests when bulls are about 5.5–6 yr of age. The merit of commercial semen could be increased by using the bulls with the highest estimated breeding values from both the sib test group and the progeny test group rather than only from the latter. With current selection rates (20%) among progeny-tested bulls for commercial use, current genetic trend (0.1 SD units per year) in bulls and with the equivalent of 3–7 full sisters per bull, the relative genetic superiority of semen from the combined groups could be from 1.10 to 1.20 times that from the progeny-tested group alone. Key words: Embryo transfer, sib testing, progeny testing, commercial semen

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