Process is still difficult, costly, unsettling

PHILADELPHIA — Like any good mother cow, she scampered around the pen, doing her best to stay between her calf and curious visitors.

The odd thing was that the "mother" was a black-and-white Holstein, but her calf was a stocky, reddish-brown Texas Longhorn.

Missy, the Texas Longhorn, was a clone of a prized member of a New Mexico herd that died young. She was implanted as a seven-day-old embryo in the Holstein, known as No. 97.

For now, Cyagra Inc.'s cloning business is limited to such animals not raised for food, but that could change this year.

The U.S. Food and Drug Administration issued a draft report Dec. 28 saying "meat and milk from clones of adult cattle, pigs and goats, and their offspring, are as safe to eat as food from conventionally bred animals."

That FDA report — which also kept in place a voluntary moratorium on the use of cloned animals for food — set the stage for a new round of debate over agricultural technologies.

A survey last year by the Pew Initiative on Food and Biotechnology found 64 percent of Americans were uncomfortable with animal cloning, the Los Angeles Times reported.

Even as genetically modified crops advance rapidly across America's fields, skepticism and outright rejections from retailers and food companies could keep cloning's business prospects in check.

Dealing with clones is complicated for the industry because there is no way to test for cloned products, and the FDA generally does not require labels on foods it deems safe, such as those containing ingredients from genetically modified crops. That means companies will have to do their own enforcement if they are to avoid cloned animals.

Cloning is not new to the supermarket. Apples, for example, do not come from seeds, but rather from clones made by grafting.

But even if food companies and consumers were to embrace animal cloning, its cost would likely prevent mass-produced clones filling supermarket dairy and meat cases, at least for the next decade.

Cyagra, for example, charges $17,000 for a healthy calf, said Steve A. Mower, director of marketing for the subsidiary of an Argentinian agricultural conglomerate.

That is prohibitively costly for most dairy farmers, who pay as little as $15 to artificially inseminate a cow.

Animal clones are "not going to be used for food production," said Terry D. Etherton, a professor of dairy and animal science at Pennsylvania State University in State College. "This will be a technology to clone genetically superior animals that are used for breeding."

Cyagra has been selling clones since 2001 and now produces about 60 a year, Mower said, the majority of the dairy and beef cattle prized as show winners. He said 25 percent to 30 percent of its clones are Texas Longhorns for wealthy hobbyists.

The process of cloning cattle at Cyagra begins with a pencil-eraser-size piece of skin from the ear of the donor animal.

When the tissue arrives at Cyagra, Joshua Mann or another technician processes the skin to extract fibroblast cells, which contain the animal's complete DNA. Those cells grow in an incubator for two weeks. Those cells can be used immediately for cloning or can be frozen and stored.

Cyagra charges $1,000 to grow a cell line. That includes the first year of storage in liquid nitrogen. Thereafter, the storage fee is $90 a year.

To create the clone, Cyagra harvests immature eggs — called oocytes — from ovaries shipped overnight from a slaughterhouse in Wisconsin.

Those are stained with a dye that attaches to the DNA in the oocyte, so it glows a brilliant blue under black light. Using a tube that measures 1.2 millimeters on the outside and is sharpened to a nearly invisibly fine point, Mann removes the DNA.

Mann then injects a cell from the animal being cloned into a precise position in the egg and fuses it with an electrical or chemical shock. If the fusion occurs, cell division will be visible under a microscope in 16 to 24 hours.

The embryos spend seven days in incubators, after which certain embryos are selected for transfer into "recipients," such as No. 97, Missy's surrogate mother. "In nine months, if everything goes right, we have a calf," Mower said.

Cloning is so costly because the process is still dogged by a low efficiency rate.

Of every 150 oocytes harvested from ovaries, only half are at the right stage of development to be used for the DNA transfer.

Of those 75, only three-quarters, or about 56, are "fertilized," meaning that the transferred DNA fuses into the recipient cell.

From there, 25 percent of the eggs, or 14, develop into embryos that can be transferred into one of Cyagra's 130 recipients.

Finally, only about 15 percent, or 2, of the implanted embryos lead to a birth — up from 2 percent in 2001, Mower said. That improvement has helped bring the cost of a cloned calf down to $17,000 from $25,000 in 2001.