Featured Post

Dr. Jamie Courter is your Mizzou Beef Genetics Extension Specialist

Image
By Jared E. Decker Many of you have probably noticed that things have been a lot less active on the A Steak in Genomics™   blog, but you probably haven't known why. In January 2021, I was named the Wurdack Chair in Animal Genomics at Mizzou, and I now focus on research, with a little bit of teaching. I no longer have an extension appointment. But, with exciting news, the blog is about to become a lot more active! Jamie Courter began as the new MU Extension state beef genetics specialist in the Division of Animal Sciences on September 1, 2023. I have known Jamie for several years, meeting her at BIF when she was a Masters student. I have been impressed by Jamie in my interactions with her since that time.  Dr. Courter and I have been working closely together the last 6 weeks, and I am excited to work together to serve the beef industry for years to come! Jamie holds a bachelor’s degree in animal science from North Carolina State University and earned a master's degree in animal...
7 comments

The Random Shuffle of Genes: Putting the E in EPD


 What does the “E” in EPD actually mean?

Expected Progeny Difference.

That word expected matters.

A calf gets about half of its DNA from its sire and half from its dam—but it doesn’t get a perfectly predictable half. The genes passed from each parent are a random sample, which means full siblings can be genetically different from one another.

That random shuffle of genes is one of the reasons EPDs are predictions of average progeny performance, not guarantees of what every individual calf will do.

It’s also part of the reason genomic information can be useful. By giving us additional information about the genes an animal actually inherited, genomics can help improve our prediction of that animal’s genetic merit.

I recently updated the MU Extension publication “The Random Shuffle of Genes: Putting the E in EPD” to help explain the science behind one of the most commonly used tools in beef cattle genetic selection.

If you've ever wondered why an EPD is an expectation rather than a promise, this article dives into the reasons why!

Read the full MU Extension article:
The Random Shuffle of Genes: Putting the E in EPD — G2012

Popular posts from this blog

New Show-Me-Select Sire EPD Requirements Announced

Image
At the January 4th Show-Me-Select Board of Directors meeting, new service sire EPD requirements were approved. All sires, artificial insemination and natural service, must meet minimum Calving Ease Direct (CED) EPD requirements. In addition to yearly updates, two changes were made. First, no Birth Weight EPD requirement will be published. All commonly used breeds now have CED EPDs available. Second, all breeds in the International Genetic Solutions (IGS) genetic evaluation are now set to a common requirement. In the summer of 2018, breeds within the International Genetic Solutions switched to a single-step BOLT multi-breed genetic evaluation. The EPDs for animals in the IGS genetic evaluation are directly comparable across breeds. In 2017, the Red Angus requirement for CED was a CED of 8, which represents the 30th percentile. Less than 5% percent of heifers breed to a bull with a CED EPD of 8 or larger had calving difficulty. We feel that this require is meeting the need to re...
Read more

Show-Me-Select Board Approves Genomic Testing Requirement for Natural Service Sires

Image
All bulls purchased after February 1st, 2019 for use as natural service sires in the Show-Me-Select Replacement Heifer Program ™  must be DNA tested to have genomic-enhanced EPDs. All bulls used as natural service sires after February 1st, 2020 must have genomic-enhanced EPDs, regardless of when they were purchased. Seedstock producers classifying bulls as Show-Me-Select qualified in sale books must have genomic-enhanced EPDs on those lots. Bulls purchased prior to February 1st, 2019 will be grandfathered into the program, as is the common practice with all natural service sires. However, this grandfather grace period will end February 1st, 2020. At that time for a bull to qualify for use in the program, it must have genomic-enhanced EPDs. Why the change? The Show-Me-Select Replacement Heifer Program has the goal of producing premium heifers that perform predictably as 2 year olds. The program has a history of requiring Show-Me-Select producers to go beyond typical...
Read more

Bob Hough Comments on Changes at Breed Associations

Bob Hough recently posted the following comment on Facebook (posted with his permission): Early in my career at a breed association, the much beloved American Angus breed executive told me that the secret to success running a breed association was to have a top junior program, keep the books straight, and make sure the numbers (EPDs) don't change. This philosophy meant Angus valued stability in their genetic predictions over keeping them up-to-date with the latest science. The Angus Association also marketed extremely effectively the infallibility of their EPDs because of the size of their database. I will start with the later. Yes, a database needs certain critical mass to make sure the animals are tied, but that can be achieved in a modest size database. After that, data quality far and away outweighs data quantity in assuring the most precise and reliable EPDs possible. On the former point, Angus breeders are simply not use to change. This is not the case in most breed associ...
Read more