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
1 comment

BIF 2017: The Power of Index Based Selection

Donnell Brown
R. A. Brown Ranch

 Darrh Bullock
University of Kentucky

 Larry Keenan
Red Angus

In the history of selection, we used used visual appearance and local adaptation to create some breed creation. We then moved to actual performance. We started weighing and measuring cattle. Then scientist used statistics to analyze this data and produce sire summaries and EPDs. We have now added genomics to this process. Prior to the release of Milk EPD there was no change in milking ability in Angus cattle.

We started with visual appraisal. We then did visual + actual weights, visual + adjusted weights, visual + EPDs, visual + EPDs for economically relevant traits, and visual + GE-EPDs. Now, we need to move to visual + economic selection indexes.

Don't overload producers with too much information!

We don't need to be double reporting data. Genomics goes into GE-EPDs; no need to publish genomic percentiles. Indexes simplify the information we present to commercial producers.

Prior to the release of Hereford's  BMI index, there was improvement for maternal profit. After the release fo the BMI index, genetic progress was even more rapid.

There was a field-test for $B. They breed two sets of steers. One from a low $B group of bulls and a second from a high $B group of bulls. The value difference predicted from the index was $187. The actual profit differences were greater than $200.

There are terminal, weaning/replacement indexes, and overall indexes.
The industry needs to improve terminal indexes. It is important that we have calving ease direct and feed intake need to be included in these indexes.

There are a small number of weaning/replacement female indexes. These are lacking calving ease maternal. Further we need further improvement in fertility and maintenance EPDs.

There are lots of all-purpose indexes. These carry it all the way through. From conception through slaughter.
Most of these indexes contain a measure of fertility. However, sometimes the EPDs used for fertility are indicators of fertility, and not direct measures of the economically relevant traits. We also need to work on adding feed efficiency to these all-purpose indexes.

Indexes work.

But, there are some keys to successful implementation, which include:
Develop a breeding objective

  • Management
  • Marketing
  • Environment

We need to identify selection index that most closely matches your breeding objectives.

The correlation between $W and $B in Angus is about 50%.

Darrh identified an outlier bull that had a -2 dollar $W and 170 dollar $B.

Don't make the mistake of sitting on the sidelines if the selection index scenario doesn't perfectly match your operation.

Red Angus was one of the last breed associations to adopt selection indexes. Keenan encourages the audience to learn from Red Angus' mistake. Again, don't sit on the side-line.

Do not panic if market values change, selection indexes are very robust.

Herd Builder is Red Angus' all-purpose index. If you look at HB vs HB without CED the correlation between the two is 0.97. If you compare HB vs HB witouth WW or ADG the correlation is 0.93. If you compare HB vs HB without Carcass the correlation is 0.99. If you compare HB vs HB without  Carcass of Feedyard, the correlation is 0.89. However, if you remove Stayability from HB, the correlation is only 0.74. This highlights the importance of stayability for profit.

Realize that some traits in an index have thresholds or optimum is not maximum.

What does the future hold for indexes?
Increased number of ERTs
Increased number of selection indices targeted to specific production systems
Improved genetic evaluations due to improved genomics technology and inclusion of commerical data
Multi-breed indices

Take home messages:
Selection indices are simple to use
Facilitate genetic improvement in profitability
Available for major production/marketing systems

Know what is under the hood.
What traits are included?
Is calving ease acceptable for my intended use?
Do I need to select for or monitor additional traits?

Selection indices are robust to economic changes. Use indexes!
Location: Athens, GA, USA

Comments

Post a Comment

Popular posts from this blog

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 cat
Read more

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

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