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Jim West and Marianna Jahnke perform a biopsy on an embryo to collect two cells for genetic testing.

IOWA STATE (US)—A team of researchers is working to determine the genetic makeup of calves by testing before they are born, or even earlier—before pregnancy.

If successful, the process would save the time, effort, and expense of producing a calf only to find out that it has genetic defects that render it of little value. Currently, biopsy samples of only a few cells have been so small it has been impossible to accurately read the genetic information.

“There were limitations to the process,” explains Jim West, director of Food Supply Veterinary Medicine at Iowa State University. “You can’t take very many cells when you do the biopsy. You have to leave enough cells to get a pregnancy.”

But the new technology may allow scientists to get accurate information from the small sample and still keep the embryo viable, even if it is frozen for long-term storage.

“Our research is looking at the ability to biopsy the embryo, freeze it, and then do a variety of tests on the sample after only seven days from when it was conceived,” West says.

Testing for traits can be simple, like checking the calf’s sex. More complex testing can screen embryos for genes that will indicate whether calves will carry traits for beef tenderness, feed efficiency, nutrition, and more than a dozen others.

Complex testing is beneficial, because overseas markets have specific preferences for how their beef and dairy taste. The new technology will allow producers to market embryos with specific traits to the markets they best fit, according to Paul Plummer, a clinician in Food Supply Veterinary Medicine.

“The new test allows very small samples,” Plummer explains. “Also, it is affordable for the producer. It is also modular, so we can test for different traits. Finally, it is adaptable. When new diseases are identified we can change it.”

Another benefit is that embryos already in storage can be thawed and tested for diseases that may have not previously been detectable. These types of tests may allow many diseased cattle to be avoided.

“Testing is going to happen,” says West. “Right now the testing happens on animals that are already born. This test will allow us to go back a generation and only select those that have the desirable traits.”

The study is being funded by a Grow Iowa Values Fund Grant.

Iowa State University news: www.news.iastate.edu