The case of cattle from Enderby Island illustrates that it is possible to resurrect races from extremely limited genetic material. However, it also shows that the process is complicated and requires much time and resources.
Enderby is a small island located 320 km south of New Zealand. The cattle came to the island in 1894, when WJ Moffett Invercargill obtained a lease of land and landed 9 copies of Shorthom. 1930 was the agricultural activity on the island was abandoned, and feral cattle remaining. After 100 years of survival in the harsh climate of Enderby, a diet based on scrubs and seaweed cattle were tough, small, compact and well suited. In 1991, to help conserve local wildlife, the Enderby cattle was slaughtered. Sperm and oocytes were obtained from dead animals for cryopreservation, but failed attempts to fertilize oocytes and found that race Enderby was lost forever.
The following year, members of the New Zealand Association for the Conservation of Rare Breeds NZRBCS, they found a cow and a calf on the island. They were captured by helicopter and were transported to New Zealand. The subsequent death of the calf meant that the "Lady", became known as the cow, was the latest issue of Enderby cattle. The attempts to produce another calf by artificial insemination and MOET, using cryopreserved semen of bulls slaughtered on the island. Seemed again that the race would become extinct. However, 1997, in collaboration with AgResearch NZRBCS managed to produce a calf, Elsie, cloned from somatic cells of the Lady. The following year another four cloned calves were born. In parallel, had managed to produce a bull Enderby through in vitro fertilization using cryopreserved sperm and eggs of the Lady, who was called Derby. Two of the clones died later, but in 2002 two calves were born by natural mating Enderby between Derby and cloned calves. Historic
Timeline of the Auckland Islands. NZRBCS, 2002. Wells, 2004
http://www.fao.org/docrep/012/a1250s/a1250s00.htm
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