Duplicating deliciousness Researchers clone cattle with high quality carcasses
By Jennifer Carrico
Duplicating high-quality lean beef may be a faster process, thanks to researchers at West Texas A&M University.
“Every once in a while when I have been in a beef processing facility, I would see a Prime, Yield Grade 1 carcass. It really isn’t very common. But when I thought about how we could increase the chance, cloning came to mind,” said Ty Lawrence, meat science professor and director of the Beef Carcass Research Center at WTAMU.
Lawrence said the chance of a yield grade 1 carcass is 8 percent to 12 percent of the general beef population, while a Prime carcass is only 3 percent of the general population. When looking for a carcass that is both, the chance is only 0.03 percent of the general population.
“It’s just not very common to get a high marbling carcass that qualifies to be a yield grade one,” Lawrence said. “Yield Grade 1 carcasses are generally Select grade and Prime carcasses are generally yield grade 3 or 4. So that’s why this combination becomes even more valuable.”
Lawrence wanted to find a way to recapture the high-quality lean carcass. He knew of other successful cloning research and thought that could be the way to duplicate this as well.
“The challenge we had was how to capture the needed genetic tissue from an animal that was already dead,” Lawrence said.
In the fall of 2010, Lawrence and his team of professors and students partnered with others outside the university and started collecting samples on carcasses which met the defined characteristics they were looking for.
Once the desired carcasses were identified, a muscle biopsy was collected and then divided into three samples. Two samples were sent to two commercially available gene marker companies to verify what the carcasses showed phenotypically were confirmed by DNA tests.
“We wanted to confirm that these traits could be passed on through genetics and weren’t products of their environment,” Lawrence said.
Some of the samples that were originally collected were shown to be highly influenced by the environment, while others showed unique DNA markers for the traits of marbling, muscling, fat thickness, feed efficiency, growth and others important in carcass quality.
“Next we had to determine if we could capture the right genetics and in the long term that we could create a new breed of cattle with high carcass quality through cloning backwards,” Lawrence said. “In other words, we had to be able to identify the genetics and then make cloned animals from a carcass.”
The tissue samples that were positive for both the DNA markers and the carcass phenotype they were looking for, were then cultured in an attempt to grow cells from samples that had been tissue banked.
“Growing the cells from a carcass that had been harvested five or more days prior to the tissue collection didn’t always work,” Lawrence said.
ViaGen, the company used to do the cloning work, did get cell lines from a steer and heifer carcass to grow and these viable cells were used to create the clone bull calf named Alpha and the three heifers named Gamma.
Alpha is a bull who’s breeding is 86 percent Angus and 14 percent Brahman. According to Lawrence, he was cloned from a steer carcass that was USDA Prime, Yield Grade 1. The heifers—Gamma 1, 2 and 3—were cloned from a heifer carcass that was also USDA Prime, Yield Grade 1.
“These cattle are a statistical rarity,” Lawrence said. They have only found 29 carcasses since the fall of 2010 that are Prime and Yield Grade 1.
Finding new carcasses to sample is like being where lightning is going to strike, Lawrence says, with that being one of the biggest challenges.
“We are continually looking for new carcasses to use as samples, and we are continually making decisions as to how we can advance this work to help the beef industry,” Lawrence said.
To accomplish the actual cloning, embryo transfer, birth and care of the clones, a group of experts from the university and the private sector worked together to make it a success.
Veterinarians, embryologists, cattlemen, university faculty and students worked together to raise the original 4 clones. Those animals are now being bred to see how their progeny will measure up in the end results.
The three heifers were super ovulated and inseminated with semen from Alpha when they reached mature age. This resulted in 23 grade one embryos, which were transferred into recipient cows. Out of the 23 transfers, 14 viable pregnancies will due to be born in February 2015.
“We are excited to see what the results will be from mating two Prime, Yield Grade 1 animals to each other. We know we likely won’t get all cattle carrying that high of quality, but even if we have high Choice carcasses that are Yield Grade 2, we are improving carcass quality,” Lawrence said.
The WTAMU researchers hope to find cattle that are sought after in the industry. Alpha currently resides at a bull stud where semen is being collected and frozen. Lawrence said they have found a cowherd in Kansas they will be artificially inseminating with semen from Alpha to see what impact the bull alone will have on his progeny out of cows of unknown carcass quality.
“If Alpha proves to show improvement in carcass quality of his calves, then it is likely for semen to be sold on him or others like him to help with carcass quality,” Lawrence said. “And down the road, we may be able to offer not only semen, but also embryos and live animals for sale from this program.”
In 2006, the Food and Drug Administration ruled cloned animals are safe to go into the food system, so Lawrence isn’t concerned about his research causing any concern. The original clones—Alpha and Gamma 1, 2 and 3—will live out their lives at the university’s farm and will continue to help with this research throughout their lifetime.
Jennifer Carrico can be reached by phone at 515-833-2120 or by email at firstname.lastname@example.org.