BEEF Online Magazine
A 10:30 p.m. phone call from a faculty member isn’t something Dean Hawkins, head of the Division of Agriculture at West Texas A&M University (WTAMU) in Canyon, usually looks forward to.
However, this one from Ty Lawrence, head of the Beef Carcass Research Center on campus and the university’s resident “meathead,” was different. Lawrence had an idea. “I’ve said to myself many times over the years when watching a Prime, Yield Grade (YG) 1 carcass go by on the rail, ‘We should have cloned that animal instead of killing it,’ ” he says.
So, throwing caution to the wind, Lawrence proposed to Hawkins that WTAMU undertake a cloning project unlike any other ever envisioned. That is to take a Prime, YG1 steer carcass and “reverse engineer” the genetics to produce a live bull.
Hawkins’ answer was swift. “No,” he said. “Let’s clone a Prime, YG1 bull and a heifer.”
And that’s how, back in 2010, WTAMU’s groundbreaking cloning experiment got its start.
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The fruits of that idea — an Angus bull named Alpha, born in July 2012, and three Angus heifers named Gamma I, Gamma II and Gamma III, born in November and December 2012 — are now ready to take part in the next phase of the research. That’s to see if a cross of two clones from Prime, YG1 carcasses will produce similar offspring when mated.
Genetic rarity
Most consider a Prime, YG1 carcass to be the pinnacle of genetic success in the beef industry. The reason Lawrence felt so disappointed when he watched one roll by on the rail is because that genetic combination is so rare. “Muscle and fat are antagonists, so a Prime, YG1 animal is an extreme rarity.” In fact, he says, it only happens 0.03% of the time.
On the other end of the scale, a Standard, or no-roll, YG5 is an extreme rarity. “Those events just don’t go together,” Lawrence says. That’s why Choice YG3 is the center point in most packer grids. It’s the most common outcome, even in a breeding program designed to emphasize carcass quality.
“Our long-term goal in the research is to see if we can move the needle in the percentage of genetically superior, Prime, YG1 carcasses that are produced in the commercial cattle system in the U.S.,” Lawrence says. “And how far can we move it? We don’t know what that answer is. But we hope to, in the next few years.”
Since the research began in 2010, Lawrence and his team have identified 30 Prime, YG1 carcasses. When they find such a carcass, the research team collects a quarter-sized muscle tissue sample. Half the sample goes to Viagen in Cedar Park, TX, to be tissue-banked. The other half goes to a commercial DNA laboratory for genetic analysis.
Based on the DNA results, many of the carcasses prove to be an accident of environment more than a result of the right combination of genetics, Hawkins says.
“Then we have cattle within that larger pool where their DNA says they aren’t completely a statistical rarity,” Lawrence says. “This animal has genetics that are high in USDA Quality Grade and growth. We take those animals where the DNA says the genetics are reasonably likely to occur again, and clone that animal” using somatic-cell nuclear transfer reproductive technology provided by Viagen.
The unique thing about the project, Hawkins says, is that Alpha the bull and the three Gamma heifers were products of the commercial cattle system. They came from commercial cowherds, were fed in commercial feedyards and received the benefit of any production technology the feedyard used.
“We didn’t know what they looked like,” Hawkins says. All they knew was they had a highly desirable, statistically rare and commercially valuable carcass in front of them.
Because the cloned heifers are too valuable to risk breeding artificially and carrying a calf, they were bred with Alpha semen, super-ovulated in February and March, and the embryos implanted in recipient cows. “We don’t know what Alpha’s birthweights would be; we don’t know all the things that matter to cow-calf guys,” Hawkins says. “So we won’t chance breeding him to the heifers.”
Depending on how many embryos they get, the researchers will have a fair number of calves that will yield data on traditional growth and production traits. Among these are birthweight, average daily gain, feed efficiency and others.
Extensive research
As more Prime, YG1 carcasses come rolling down the line in a packing plant, the research will continue.
“We skipped the Beta line initially,” Lawrence says, “and we’re in the process of cloning the Beta line now. They will be red or white, based on the DNA.”
Because the DNA test is Angus-based, the results only told them that the carcass wasn’t Angus. The researchers must wait until the calves are born to see what they have for breed makeup. “And we’re out there looking for Delta, Epsilon. It will continue.”
Hawkins and Lawrence emphasize that the research is at the very beginning stages, but the potential is exciting. “The Alpha-Gamma cross may be a complete bust. We don’t know,” Lawrence says. “But the Gamma-Epsilon cross might be a home run. So we plan to collect several steer carcasses, clone them; several heifer carcasses, clone them; and cross them in every possible way. The likelihood that one of them is a rock star is pretty high.”
Even though it’s still 2-3 years before the project yields the first real-world, commercially produced data, it would take up to 60 years to produce the same results without the technology. And that’s if the researchers had been able to trace back the Prime, YG1 carcasses to the cow and the bull that produced them. This way, Lawrence says, they find a good carcass and hit the reset button on those genetics.
In addition to Hawkins and Lawrence, the project involves many others, some of whom donated their time and expertise to keep costs in line. Those include WTAMU faculty David Lust and John Richeson, and Ph.D. student Kelly Jones, who husbanded the cloned calves day and night. The WTAMU faculty partnered with Gregg Veneklassen of Timber Creek Vet Clinic in Canyon, TX, and Jason Abraham, a rancher from Canadian, TX, along with embryologists Todd Stroud and John Nelson, and scientists from Viagen.
As the project continues, Hawkins says the university and its partners have a business plan in place to take the genetics to the cattle industry. According to Lawrence, they hope ultimately to create a new line of cattle, a composite of the best of the best of the best from all existing breeds and their crosses.
“The other offshoot of this is, using the same techniques, what if we were to identify cattle that came through a feedlot that for whatever reason, didn’t get bovine respiratory disease?” Hawkins says. “The genetics of the immune function is a huge unknown. So there are a lot of applications to this. We’re just using technology to make things better. That’s all it is.”
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