New technique increases survival of cloned cows

A Black Angus cow clone at the University of Georgia

By Alex Walker
CNN

ATHENS, Georgia (CNN) -- Scientists at the University of Georgia announced a breakthrough Tuesday in cloning technology, which they say makes the process more efficient. The new procedure, according to lead scientist Steve Stice, has a success rate of one in seven when it comes to the viability of embryos for Black Angus cows.

"The process is the most successful embryo transfer in producing live cows," Stice said. "Other technologies today have a viability rate of about one in 20."

CLONING TECHNIQUES How do scientists clone animals? Click here to find out

The new procedure differs from conventional cloning techniques in the application of a chemical inhibitor during the first two to three days of the process. A chemical inhibitor, undisclosed by Stice, is applied to a cell taken from the donor cow before the cell is actually used in the cloning process. Stice said the chemical produces a more uniform cell, and that is the key to increasing the viability rate of cloned embryos.

Lead scientist Steve Stice explains how eight healthy calves were successfully cloned

"Oftentimes, we don't know how homogeneous one cell is from the next," Stice said. "By using the chemical inhibitor before cloning, we prepare it for the process by making the cell more uniform. This results in a more viable embryo throughout the nine months in utero and thus a higher birth rate for live offspring."

Stice and his team have successfully engineered eight Black Angus clones, all identical to the infertile cow from which the genetic material was obtained. Medusa, Bond, Beth, L-C, Fat River Dumpling, Full Deck, Lucy and Purt' Near Perfect are all females aged 2 to 4 months. The oldest was born in February and the youngest born in April.

The calves will be sent to breeding stations for more study. The university's Animal and Science Department is also working to clone pigs using the same technology.