By: Robin Salverson, Cow/Calf Field Specialist, SDSU Extension
Yield Grade 1 carcasses occur 12.4% of the time in the fed cattle population. Rarer are cattle that grade USDA Prime, approximately 2.25% of the population. What are the chances of a Prime Yield Grade 1? Approximately 0.03% of the fed beef population in the U.S. matches the desired Prime Yield Grade 1 carcass.
How can the beef industry increase the percentage of these superior carcasses? Dr. Dean Hawkins from West Texas A&M University shared at the Range Beef Cow Symposium, how imagination can be turned to reality when working with tissue from exceptional carcasses and cloning. Awareness and the potential of cloning in the livestock industry was first noticed in 1996 with the cloning of "Dolly" the ewe. Since "Dolly" more cloning has occurred in the livestock industry including cattle, horses and sheep. Typically clones are produced from a tissue biopsy from a superior living sire or dam.
However, West Texas A& M Beef Carcass Research Center wanted to start with the end product, the carcass. They took on the challenge of identifying the rare Prime Yield Grade 1 carcasses and collecting muscle tissue samples to clone a sire and/or dam that will pass on the desirable carcass characteristics.
Tissue samples were collected and tested at a commercial gene marker company to verify that what was seen phenotypically (Prime Yield Grade 1 carcass) at the slaughter house matched the DNA markers. The goal was to increase the likelihood of the traits for carcass, growth and feed efficiency would be passed on. The animals that matched both phenotypically and genetically were cultured.
Interesting, that when they confirmed the animals that had both the phenotypic traits and the gene markers for growth, feed efficiency and carcass traits it narrowed the percentage of animals eligible to be cloned to 0.006% of the fed beef population. Since the project started in 2010, 1 cloned -bull calf (Alpha) and 3 cloned-heifer calves (Gama) have been born from tissue collected from USDA Prime Yield Grade 1 carcasses.
This project is in its infancy; however, it creates excitement in the livestock industry. Can we start moving away from select and low choice carcasses to a higher percentage of high choice and prime carcasses to meet consumer demands? The future for this project involves super-ovulating the cloned-heifers and inseminating them with Alpha semen. Additionally, testing will be completed for DNA markers for carcass merit and growth efficiency along with yield and quality grade. Likewise, additional cows will be inseminated with either Alpha semen or another purebred bull to make a comparison. There will be much more to come from this project in determining whether or not the animals begin produced are genetically superior animals.