Beef Business

Matt Woolfolk

director of performance programs

Endless Possibilities

Many of you were probably hoping to leave complex genetic talk behind when you walked out of that college classroom for the last time. As technology advances in the seedstock cattle industry, you may be having nightmare flashbacks to those genetics courses! Genomic testing and that technology come to mind as the prime example that makes many cattle breeders break out in a cold sweat.

While it is discussed at length the importance of genomics and utilizing the technology to enhance the accuracy of an animal’s EPDs, it’s a complicated concept to explain. Many of the brightest brains in our industry struggle with how to relay the technical information involved in genetic evaluation to a practical perspective. Instead of rambling on about the technicalities, perhaps a visual is the best teaching tool to demonstrate how utilizing genomics can help us better identify the true genetic values of our Shorthorn cattle. While this demonstration may overly simplify the complex process, I call this a successful exercise if it helps you grasp it even a slight bit better.

In this illustration, we have a sire and dam who produced four full brothers. The colored bars constitute the genetic material of each animal, beginning with the grandparents of the four brothers. Since basic genetics teach us that any mammal inherits 50% of its genetic material from each parent, our sire and dam each have half their genetic material from one parent (thus one bar of each color). Now, when they are bred to each other, they will pass on 50% of their genetic material to each offspring. Of course, knowing which 50% they will pass on is the part that makes cattle breeding so challenging! In the four sons, each has 50% of their genetic material from the sire, and 50% from the dam. None of these four sons look much alike based on their genetic material. This occurs because of a process known as meiosis, which creates the reproductive cells of both the Sire and Dam. The genetic material of the parent is essentially split in half, creating reproductive cells that are not identical to each other. If you’ve ever wondered why your brother or sister was so different from you while having the same parents, meiosis is to blame!

Countless combinations of genetic material can be created thanks to the production of reproductive cells with meiosis. In this simplified exercise, there are MILLIONS of possible genetic combinations that can be made for one animal. Knowing that cattle have 30 pairs of chromosomes, imagine how many possible combinations can be made when sperm and egg meet! If we were to think about what economically relevant traits are controlled by genetics (all of them), the diagram gets even harder to grasp. Is Son 1’s “yellow” genetic material the right pieces to make him a calving ease sire? Did Son 2 inherit the right combination of “blue” and “red” from his dam to provide extra growth to his calves? Does the combination of all genetics make Son 3 or Son 4 a better option to add carcass quality in their offspring?

How can we answer those questions? With genomic technology! When you take a sample and send it to ASA for genomic testing, that test is analyzing the genetic material of that animal to determine which material is there in their DNA. Through lots of research, geneticists have been able to identify certain genes or groups of genes that have specific effects on the various traits of importance. The genomic test looks at the genome of Son 1 and determine if he has the genetic material that positively influences calving ease, or if Son 2 inherited the right material from mom and dad to be a high growth bull. With that analysis of their genomes, the data gathered is applied to the traits that we have EPDs for, and that information is submitted to our weekly EPD runs. The data from the genomic tests are what influence the increase in accuracy and possible changes in a genomic tested animal’s EPD values.

We have been asked before if we are able to see and share the information that goes from the genomic test and into the EPD calculations. That information isn’t shared with the ASA, so it is not something we can pass along for you (or us) to analyze. Just like you, we only see the results of the genomic test through the increased accuracies and possible changes in values on the animal’s genomically enhanced EPDs.

Cattle breeding has always been a bit of an art form, but scientific concepts play a growing role in the craft. With the concept of genomics, identifying genetic material, and the vast number of genetic combinations, it’s ironic that artwork can help explain the scientific concept. Since cattle breeding is far from being black and white, it helps to add a little color =sometimes.