Embryo transfer (ET) is a viable reproductive technology and is used to propagate the genetics of outstanding dams. Embryo transfer is basically used to increase the reproduction rate of valuable cows, the rapid multiplication of rare animals, and for export (frozen embryos take up less room and weigh less than cows). The "donor" female (a cow that is genetically superior and will donate her eggs that are fertilized by the semen of a similarly genetically outstanding male) is superovulated, causing her to release more than one egg at ovulation (as few as two or as many as two dozen, but not all viable). The cow is inseminated, and six to seven days later the eggs are collected (flushed) and graded (for quality). The better-quality eggs can be transferred fresh to cows that have been synchronized to come into heat the day of the flush (recipient cows), or they may be frozen (like the semen used in AI). Fresh transferred eggs generally have a higher pregnancy rate than frozen and implanted eggs (into cows in heat, of course). Frozen eggs have a 50% success rate usually. Cost per live calf varies depending on fresh or frozen egg use and who owns the recipient cows. All of the calves born are full siblings (same sire and dam) but are not genetically identical, nor will they look or perform the same. The average genetic relationship between full siblings is 50% (50% of the genes are exactly the same as compared to half siblings where only one parent is shared, the case in most cow herds, where only 25% of the genes are the same). Embryo transfer is widely used today by some seedstock producers.

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