Cloning of Livestock Nears

In 1996, when Dolly the sheep became the first mammal to be cloned from an adult cell, scientists were excited that the technique could lead to cures for disease. A decade later, as cloning technology has progressed, livestock producers are excited for a different reason: They believe it could bring better steaks and lamb chops to supermarket meat counters. For all the controversy, cloning isn't a radical departure from assisted breeding techniques common in the livestock industry, such as in vitro fertilization and artificial insemination. It allows breeders to create an exact genetic copy, essentially an identical twin, by transferring cells from an animal into an egg, which is then implanted into a surrogate mother. The process can be used to produce superior traits in an animal herd - for instance cattle that have lean but tender meat or dairy cows that are proven milk producers. By reproducing the healthiest, most disease-resistant animals, cloning can minimize the need for antibiotics, growth hormones and other chemicals that can enter the food supply. Conventional breeding strives for the same goals less effectively.