ABSTRACT
Embryos -- collection, preservation, and transfer have been major news items in 1984. All the technologies included here involve micromanipulation of embryos. Some of the exciting potential advances in commercial livestock production from genetic engineering have been reviewed. Artificial insemination increases the potential prolificacy of males much more than embryo transfer (ET) does for females. The reproductive technologies combined in artificial insemination have made possible major genetic improvements in the performance of commercial livestock, especially cattle. Consequently, the most rapid rate of genetic improvement -- even for female-limited traits such as lactation is through sire selection. ET is essential to obtain genetic improvement from gene insertion, conservation of rare genotypes, and import/export of exotic genotypes. ET can play a significant role in genetic improvement by intensifying selection of dams of bulls used in artificial insemination programs. International transfer of animals has become increasingly expensive to the point that transportation costs often exceed the value of the animal.
