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Chapter 1
Historic frame of reference

The first transfer of a bovine embryo was reported in 1949 (Umbaugh, 1949), and the first calf from embryo transfer in 1951 (Willett et al., 1951). Milestones in the development of this technology have been evaluated from the point of view of their significance to our current knowledge of reproduction and to the improvement of animal agriculture (Betteridge, 1981; Adams, 1982; Betteridge, 1986). Application of embryo transfer to the cattle industry began in the early 1970s when European dual-purpose breeds of cattle became popular in North America, Australia and New Zealand. Breeders and speculators sought means to circumvent the high costs and lengthy quarantine periods linked to the importation of European breeding stock and to capitalize on premium prices that progeny from these rare dams and sires could command.

Thus, demand for embryo transfer services existed in advance of the ability of veterinarians and reproductive physiologists to supply them. This considerable economic incentive, however, inspired rapid development of practical techniques for superovulation and surgical recovery and transfer of bovine embryos, and the establishment of clinics to sell the technology to the public. Because the value of embryo transfer offspring was based on scarcity, however, the exercise was self-defeating. The inflated market for European dual-purpose breeds in North America collapsed abruptly in 1977 because the numbers of these animals increased markedly as a result of embryo transfer. During this short-lived boom, nevertheless, techniques had been improved and costs reduced. Notable was the development of procedures for non-surgical recovery and transfer and cryopreservation of embryos. With these improvements and a more realistic economic motivation, the industry now plays a useful role in the cattle industries of many countries (Seidel and Seidel, 1981).

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