Multi-breed Genetic Evaluation

Multi-breed Genetic Evaluation (13)

Monday, 15 February 2021 15:09

Nobody Shares Like IGS

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Through pooling information, the International Genetic Solutions offers better selection tools to seedstock breeders and the beef industry.

By Jackie Atkins, Ph.D         

Early in life, we are taught to share. Share with our siblings, share with our classmates, share with our neighbors. The fact that we have to learn this behavior is telling — it’s not instinctive. It’s human nature to protect what is “ours” and become territorial to ensure we have what we need to survive and thrive; however, we have seen how we all can do better by working together, sharing resources, and maybe most importantly, sharing ideas. This philosophy of comradery and collaboration is at the heart of International Genetic Solutions (IGS).

IGS aims to serve the beef industry by providing resources for genetic improvement using the best technology available and unprecedented collaboration. The IGS collaboration now has 20-million animals and nearly 300,000 genotypes from 20 different organizations. Not only is it the largest beef cattle database, but it also has a huge amount of connectivity among the different organizations. Nearly of the progeny records in the IGS evaluation have siblings in a separate database and multiple sires have progeny in as many as 12 databases. If each of these databases was an island with an isolated evaluation, we could all breathe a little easier because the evaluation would be much simpler. But, it wouldn’t be better. It wouldn’t be as accurate. It wouldn’t give the best genetic predictions of the animals in the evaluation.

Instead, the IGS model has chosen the harder path. It is complex to have one evaluation with 20 different data sources. It is challenging to have a multi-breed genetic evaluation and to account for different breed effects and heterosis. But at the end of the day, we want to provide the BEST possible genetic predictions, not only to seedstock breeders but for anyone using EPDs to select their future genetics.

The IGS model also sets aside the territorial toddler behaviors often seen in breed associations and societies. Instead of guarding our data, our material, our resources, to be used only to help our association improve, the IGS system opens the doors of communication among all the IGS partners to offer better resources to all the members and ultimately the beef industry. We all benefit from working together and sharing various perspectives from different breeds of cattle, different breed associations, and different countries but with the common goal of beef cattle genetic improvement. Beyond making the best possible genetic predictors, the staff from the various IGS partners learn from each other, share educational material, collaborate on different research projects, and work through various challenges most of us have faced independently but can get through better together.

While the future is unknown to all of us, it is certain to improve by working together towards the common good.


Monday, 15 February 2021 14:49

IGS Carcass EPD Updates

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By Randiie Culbertson, Ph.D.    |    

As with any trait under selection, breed effects will change over time. As a result, US-MARC updates their breed effects annually and the IGS Multi-breed Genetic Evaluation recently updated the breed effects in the published EPDs (as of 11/9/20). The implementation of these updated breed effects caused some changes in carcass EPDs. The adjustments are set to an Angus base and are applied depending on the breed percent of the animal. When comparing the rank of bulls with a high percentage of a breed, breeders may see a shift in the EPD value but the bulls still have the same rank among other bulls with the same breed percentage. However, reranking occurred when comparing one breed to another as well as different percentage composites.

An ongoing challenge of estimating carcass EPDs is the lack of carcass phenotypes (see article by Lane Giess about Maximum Carcass Knowledge, page 38). This lack of phenotypes creates a real challenge for the genetic evaluation to appropriately account for breed differences. With traits that have limited records and breed comparisons within contemporary groups, using field data (i.e. IGS data) can lead to unreliable estimation of breed effects. In those cases, breed effects from scientific literature are often used. The advantage of using breed effects from literature is that the effects are derived from “clean” data and often from herds with breeding systems designed specifically to obtain these breed effects. In the case of carcass trait breed differences, the IGS Multi breed Genetic Evaluation uses the breed effects derived from US-MARC.

In addition to updating the US-MARC breed effects, an adjustment to the carcass weight and rib eye evaluation is being tested to allow the inclusion of carcass records previously excluded. This change will result in an increase of 65,000 carcass weight and rib eye records. The inclusion of these records will cause the EPDs for relatives of animals whose records are now included in the evaluation to change. The IGS genetic evaluation team is in the process of testing the inclusion of these records but at the time of writing this article, the implementation date is unknown.


Tuesday, 09 June 2020 08:02


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An industry-wide collaboration is improving breeding tools.

International Genetic Solutions (IGS), a group of more than 17 cattle associations and organizations, is working across the breed spectrum to provide resources and technologies that ensure cattlemen and women along the industry chain are set up for success. 

“We’ve put together a massive collaborative effort with approaching 20 million head of cattle to provide the most scientifically-credible, the most cost-effective, the quickest, multi-breed, directly-comparable genetic evaluation on the planet,” says Chip Kemp, IGS Commercial & Industry Operations.

IGS partners and leaders across the beef industry meet virtually this week during the Beef Improvement Federation (BIF) virtual symposium, beginning June 8. 

“If you think about IGS, from a big-picture standpoint, it’s the value of collaboration,” says Tom Brink, Red Angus Association of America CEO. “Beef breeds, historically, haven’t always worked together so well, or so much, but IGS broke the mold on that. Being able to combine these data sets, more analytical power, better EPD predictions to use for all the breeds involved, IGS just really facilitates that in an unprecedented way.”

The collective effort is intended to help individuals make more informed decisions – from seedstock to commercial producers.

“The collaboration that we have with IGS will do two things: not only will it help their members sell seedstock bulls and replacement heifers but it will also help their customers, commercial producers make an informed decision in their operations. And those two things together will contribute to accelerating genetic improvements,” says Stewart Bauck, vice president of agrigenomics for Neogen Genomics. “It’s going to have a significant, important, and long-term beneficial impact on the beef industry.

Bob Weaber of Kansas State University agrees.

“Getting everybody pulling the wagon together allows the IGS team and the leading scientists in the world, working in beef cattle genetics, to accelerate the process of genetic improvement,” Weaber says. “Tools like the IGS Feeder Profit Calculator puts increased profit potential in the hands of cattlemen and women as they assign and assess the value of their stock.”

IGS, and the tools it provides, is unique, Brink adds.

 “We’re a lot stronger working together than we are individually,” he says. “We’re getting a lot better genetic predictions by doing what we’re doing, working together, so that’s really the power of IGS.” 

International Genetic Solutions (IGS) is an unprecedented collaboration between progressive organizations across the US, Canada, and Australia that are committed to enhancing beef industry profitability. The collaboration encompasses education, technological advancement, and genetic evaluation. Through collaboration, IGS has become the largest beef cattle evaluation in the world. 

More information about BIF’s virtual symposium, June 8-12, is available at

Friday, 28 February 2020 09:31

Updates to Growth Trait Predictions

Written by

Jackie Atkins Ph.D., Matt Spangler Ph.D., Bruce Golden Ph.D., and Wade Shafer Ph.D.

The genetic evaluation is constantly evolving with updates to models as new science is discovered and new technologies are available. One area under recent scrutiny is the prediction of growth traits (birth, weaning, and yearling weights, and milk). The IGS Genetic Evaluation Science Team is investigating the following five areas of potential improvement in the prediction of growth traits.

The goal of each of these changes is to improve the prediction of growth traits. Breeders and IGS partners should expect to see the implementation of improvements to growth trait prediction in the approaching months. 

 1. A new definition of contemporary groups based on the age of the dam.

Regardless of how users designate contemporary groups, the science team is considering placing all calves born from first-calf dams into separate contemporary groups (CG) from calves out of mature cows. Given the vast majority of producers actually manage this age group separately, it is reasonable to define their calves as their own CG. Handling these as separate CG is a valid way to reduce the environmental noise caused by different management strategies for this age group. 

2. Setting the genetic correlation between weaning weight maternal (milk) and weaning weight direct to 0 (compared to - 0.3).

The magnitude, and even direction, of the correlation between weaning weight direct and milk, has been long debated in scientific circles. In fact, there is a wide range of estimates that exist in the scientific literature. Given that, the science team feels the appropriate way to model these traits is to assume they are independent (i.e., genetic correlation of 0). We expect the impact of this change to be greatest for low accuracy animals.

3. Different variances for different sexes (heterogeneous variance).

Males usually have a higher growth potential than females simply due to gender. As a consequence, the variation associated with their weights also tend to be greater. This difference in the amount of variation between the sexes should be accounted for in genetic predictions. The IGS team is testing the validity of setting the variance of growth EPDs on a male base.

4. New DNA Marker subset.

As the number of genotyped animals has increased, so has our ability to estimate marker effects and identify subsets that are more predictive. Relative to growth traits, a new (and larger) subset of markers has been identified to add more accuracy to EPD.

5. Accounting for different birth weight collection methods.

When the IGS Science Team began looking into growth trait data, we discovered that not all birth weight CG followed expected amounts of variation in the weights. In some cases, weights are rounded to the nearest 2 lb increment or 5 lb increment. In other cases, the amount of variation was substantially reduced due to the use of hoof tapes (see the December 2019/January 2020 issue of the Register for more information on hoof tapes). There were also cases where the reported weights were clearly fabricated (for instance, all calves weighed 75 lb). Some of these data are useful, but they are clearly on a different scale and need to be treated appropriately. Dr. Bruce Golden developed a way to use machine learning to recognize unique features of each class of birth weight observation and predict how it was generated (e.g., scale weights, hoof tape, rounding, fabricated). By accounting for the various categories, the genetic evaluation is still able to use the records submitted that fall out of biological expectations for most scenarios, while more accurately accounting for different practices of collecting the weights. 

Wednesday, 04 March 2020 08:05


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The world's largest multi-breed beef cattle evaluation partners with the industry's leading genomics company. Here's what it means for ranchers.IGS Feeder Profit CalculatorTM - Marketing Backed by Genetics.
"We're extremely proud of the collaboration we have with IGS. It really is the first of its kind in the world," says Stewart Bauck, vice president of Agrigenomics for Neogen Genomics. "We will, along with IGS, be developing and refining a set of tools that we can make available to commercial producers so they can select superior females in a multi-breed or crossbreeding operation."
Jackie Atkins, Ph.D., Director of Science and Education says, "The IGS database is the largest on the planet for multi-breed beef cattle, and not only do we have a lot of data, but we also have a lot of genotypes in that evaluation. Because of that critical mass, we can do a better job developing DNA markers and what those markers mean for a commercial test."
During the past decade, seedstock breeders have adopted genomics to strengthen genetic prediction tools and resulting selection decisions. The IGS-Neogen partnership accelerates the effort for commercial ranchers.
"Historically, all of these types of genetic profiles have been for a single breed. If we look at geneticists and the knowledge that we've gained from their research across the years, we know that crossbreeding leads to hybrid vigor, and so being able to have crossbred commercial cows should really be the goal for any commercial cattleman because, at the end of the day, they sell pounds," says Jamie Courter, Neogen Genomics Beef Product Manager.
"We'll be able to pull from all of the information that seedstock and commercial producers report back to IGS and fully support the Igenity® Beef Profile to make it stronger and better than it is today," she says. "So it'll be a two-way street. The sales reps at Neogen will be able to drive people toward reporting information and data back to IGS while Neogen is able to pull from that data and strengthen our own products."
In the end, more data on crossbred commercial cattle reduces risk.
"That puts a proactive management tool in the hands of the commercial producer," Bauck says. "For $30 and in three weeks, I can get the same information as I could by spending $2,000 in two years to develop a replacement heifer."
Kenny Stauffer, Neogen Genomics Director of Beef Genomic Sales, says, "If you're able to tag a calf, you're able to take a tissue sample. Put the capsule in the box and mail the box to us. You send your sample to us and in 21 to 28 days, you're going to have your results."
As producers make decisions on where to spend their time and money, DNA testing offers a valuable option in finding genetic answers.
"DNA testing is a valuable tool that can get to answers faster for commercial and for seedstock producers," Atkins says. "It will never replace data recording, that will always be important, but the fact that we can squeeze more out of any single DNA test in the future, that just gives commercial producers a more informed decision to make better, more profitable choices for them." 
International Genetic Solutions (IGS) is an unprecedented collaboration between progressive organizations across the US, Canada, and Australia that are committed to enhancing beef industry profitability. The collaboration encompasses education, technological advancement, and genetic evaluation. Through collaboration, IGS has become the largest beef cattle evaluation in the world. 
I G S    S T A N D    T O G E T H E R



Data Sharing for the Good of an Industry


Matt Spangler of the University of Nebraska says the future of the beef business will depend on information sharing.


IGS and the Pursuit of Better Cattle

IGS Feeder Profit Calculator ™ Highlights Profit, Reduces Risk

Using the IGS Feeder Profit Calculator, cattlemen are able to provide sire information, regardless of breed, as well as preconditioning, weaning and health data in exchange for a Total Relative Value that compares the profit potential of their calves to the industry at large. That value, indicated on a formal certificate, can be used for producer benchmarking and buyer insight.

Superior Livestock Representative Clint Berry says such technology is in line with what he sees for buyer demand.  Continue reading.

A global collaboration of major beef breed associations seeks to empower commercial cattlemen with genetic insight and more powerful tools for better breeding decisions.

Modern-day ranching requires more information to produce better animals, and International Genetic Solutions is propelling the effort across multiple breeds. The aim is to provide more accurate selection tools that allow for head-to-head comparisons and maximum profitability — regardless of breed. “Tying all of that information together adds a lot of value to commercial and seedstock producers because it provides a set of EPDs that are comparable across breeds without doing a bunch of extra math to figure out how they compare,” says Bob Weaber, Kansas State University Extension Specialist.  Continue reading.

Wednesday, 04 December 2019 17:51

Check Out What We Have Done So Far

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By Lauren Hyde, Ph.D.            |         

Nearly a year and a half ago, on Saturday, May 5, 2018, the American Simmental Association released the first full suite of multi-breed EPDs powered by the state-of-the-art BOLT software. I have to admit that the ASA staff, with the exception of very few (maybe only Steve McGuire), was very scared as to what we would find in our email, voicemail, Facebook Messenger, and so on come Monday morning. However, it wound up being so quiet, we all heard that mythical pin drop.   I’m not saying that we were perfect in our execution, but as your members started to evaluate the new EPDs, you had some well-deserved comments and questions that we were expecting.   We knew that the software wasn’t “done”. It never will be. In fact, I was still revising the 30-year-old Cornell software as recently as two short years ago. As with the old Cornell software, we will continue to update, revise, and improve the EPDs produced by the new BOLT software. 




Check out what we have done so far:

June 2018

• Developed evaluation audit reports on incoming record counts for ASA staff and IGS partners

• Developed quality control (QC) reports for incoming genomic data

• Started clearing up erroneous and missing genotypes among all associations

• American Shorthorn Association released IGS EPDs

July 2018

• Started parallel (aka beta) testing for IGS partners yet to release IGS EPDs

• Started delivering weekly QC reports to each association through the genomic pipeline, which routes genomic data from all genomic labs to the IGS partners and then the IGS database

August 2018

• American Gelbvieh Association, North American Limousin Foundation, and Canadian Simmental Association released IGS EPDs

• Added embryo transfer data to the evaluation

• Discovered and corrected duplicate animal IDs

• Began collecting feed intake and heifer pregnancy data from IGS partners

September 2018

• Canadian Shorthorn Association released IGS EPDs

• Initiated monthly IGS partner conference calls to discuss issues and updates with the evaluation

October 2018

• Red Angus Association of America released IGS EPDs

• Developed a web-based interface for bull lookups and QC error checking for ASA staff and IGS partners

• Established a “white list” to keep animals with insignificant genomic discrepancies in the evaluation 

• Adjusted the evaluation system to add genomic data on animals without carcass or ultrasound phenotypes 

November 2018

• Implemented a Java script to compute breed composition of all animals in the IGS database at a much faster rate

• Began a research project with CSU to develop a days-to-finish EPD

• Initiated a project known as Work Order 1 (WO1) in order to:   

– Remove erroneous birth weights from the evaluation   

– Separate birth contemporary groups between calves out of two-year-old dams from calves out of older ones   

– Include heterogeneous variances for weaning weight based on sex of calf   

– Remove the moderately negative genetic correlation between weaning weight direct and maternal and set it to zero   

– Implement an updated marker subset of genomic data 

December 2018

• Added trio (sire + dam + calf) mating checks to the QC error reports

January 2019

• Began investigating multi-breed imputation

• Started evaluating the latest version of the FImpute software package

February 2019

• Began refining the Zoetis arm of the genomic pipeline

• Received preliminary results on the days- to-finish EPD research project

• Combined the heifer pregnancy (HPG) data from the IGS partners and began refining it

March 2019

• Started to investigate potential improvements to the carcass weight-ribeye area (CW-REA) evaluation

• Fixed minor bugs in the online bull lookup tool

• Added birth dates and other supplemental data to the HPG dataset

• Received the first set of health data courtesy of Darr Feedlot

• Upgraded the Postgres evaluation database

April 2019

• Started exploring modifications to the utilization of external EPDs

• Tested several scenarios in the investigation to potentially improve the CW-REA evaluation

• Updated carcass breed differences with new data from USMARC

• Fixed a small bug in the docility evaluation scripts

May 2019

• Canadian Angus released IGS EPDs

• North American South Devon Association submitted external EPDs

• Began planning for the IGS partner meeting to be held October 23-24 in Bozeman

• Started building and developing server #5

June 2019

• Developed a standard format for sharing pedigree extracts among IGS partner associations in order to catch dual-registered animals more quickly

• Released data to Colorado State University (the leaders in PAP EPD development) for development of a PAP EPD

July 2019

• Implemented multi-breed imputation software

• Installed and configured FImpute

• Implemented updates to the CW-REA evaluation

August 2019

• Added Australian Shorthorn Association data

• Added updated American Angus Association externals

• Re-calculated progeny equivalents for each trait computed by IGS

I am writing this article on September 18. In just a few days, I will be traveling from Denver to the Rhine River in Germany to find out where my maternal grandparents lived before they immigrated to Chicago and met in English school. After my excursion, I will be finishing up all of my outstanding projects so that I can retire on December 31 to pursue my dream of coaching and teaching swimming.

I am fortunate to have worked with the best team in the beef cattle industry. The ASA staff is knowledgeable, hard-working, creative, and fun. This fantastic group of individuals has shown time and time again that it is more than capable of developing and implementing innovative science-based products to help you produce cattle that make a significant genetic contribution to the beef industry. I truly wish all of you — ASA members and staff alike — much success in your efforts to keep moving the breed forward and ensuring that SimGenetics continue to have a major influence in the global market.

Thursday, 06 June 2019 07:41

IGS and the Pursuit of Better Cattle


A global collaboration of major beef breed associations seeks to empower commercial cattlemen with genetic insight and more powerful tools for better breeding decisions.

 Modern-day ranching requires more information to produce better animals, and International Genetic Solutions is propelling the effort across multiple breeds. The aim is to provide more accurate selection tools that allow for head-to-head comparisons and maximum profitability — regardless of breed.

“Tying all of that information together adds a lot of value to commercial and seedstock producers because it provides a set of EPDs that are comparable across breeds without doing a bunch of extra math to figure out how they compare,” says Bob Weaber, Kansas State University Extension Specialist.

“It’s easy to make crossbreeding decisions where we’re seeking out specific genetic traits and inputs for our production system. We don’t have to spend a lot of time trying to figure out how does breed A compare to breed B? It’s all laid out and they’re on the same base and scale.”

International Genetic Solutions, or IGS, is a collaborative effort between numerous beef breed associations from the US, Canada, and Australia, resulting in the largest and only major multi-breed cattle evaluation system. With decades of data and nearly 18 million animals in the database, IGS Director of Commercial and Industry Relations Chip Kemp says IGS is helping producers make more powerful breeding decisions than ever before.

“You can directly compare a yearling weight from a Simmental to a Red Angus to a Limousin. You can directly compare the stayability or the cow longevity from a Balancer to Angus in the system to a SimAngusTM,” he says. “It empowers that commercial client to get past all of the clutter to make smarter, wiser, more profit-focused decisions.”

IGS uses a single-step genetic evaluation model that incorporates genomic and phenotypic information on purebred and composite animals. The collaboration allows participating breed associations to gather and analyze data on traits that are difficult to measure but economically important.

“We’re able to calculate EPDs on those cattle, and these cattle bring the power of heterosis and crossbreeding to the commercial cattleman as far as increased performance in their cow herds, increased growth, and productivity in their calf crop,” says Tom Strahm of the American Gelbvieh Association, one of many IGS collaborators.

IGS also helps cattle producers verify the value of feeder calves, weighing good management practices alongside genetic merit through free tools like the Feeder Profit Calculator. The goal: Better returns on genetic investments.

“The greatest thing it’s brought is just a better system for cattle evaluations and the collaborative effort of people working together through different breed associations. When you’ve got this many cattle in the evaluation, what you get is crossbred cattle evaluations that the commercial cattleman can use,” says Mark Anderson, North American Limousin Foundation executive director. “So in the race to make the better kind of cattle, the science we’re using today, I think it’s on the forefront and getting really exciting.”

International Genetic Solutions (IGS) is an unprecedented collaboration between progressive breed associations fervently committed to enhancing commercial profitability.  The collaboration has yielded the world’s largest genetic evaluation of beef cattle with over 17 million animals and 120,000+ genotypes.

In keeping with our commitment to the cattle industry, IGS is pleased to announce the IGS Multi-breed Genetic Evaluation powered by BOLT.  The new genetic evaluation provides more predictive EPDs, better use of genomics, more accurate accuracy reported with EPDs, all with weekly evaluations.  The announcement ushers in a new era in genetic evaluation — an era made possible by a genetic evaluation system dubbed BOLT (Biometric Open Language Tools, owned by Theta Solutions, LLC).  

The concept for BOLT started in 2014 as a research endeavor between the American Simmental Association and Drs. Bruce Golden and Dorian Garrick.  BOLT is, quite simply, the most revolutionary and powerful genetic evaluation system in existence. Its power allows IGS to leverage genetic evaluation methodology that was once thought to be untenable on large databases — methodology that significantly improves genetic prediction.

In December 2016, IGS published a multi-breed stayability, the industry’s first EPD using BOLT and the first single-step methodology applied to a large beef cattle database.  Since that time, the IGS genetic evaluation team has worked toward fully implementing BOLT with an automated system that enables weekly evaluations for an entire suite of EPDs.  As of May 5th, 2018, ASA is the first of the IGS partners to publish a full suite of EPDs generated by the IGS Multi-breed Genetic Evaluation powered by BOLT.  Each IGS partner has complete autonomy to determine the release date that best fits their organization.  As such, the release of EPDs by the other IGS partners is likely to be staggered over the next several weeks.  As always, we look forward to your questions and comments about what you see.

Here are the notable changes in the evaluation:

Movement of EPDs and reranking. EPDs and indexes will change. These changes will be more dramatic for younger, lower accuracy cattle.  The IGS team has tested the changes and proven the new EPDs result in superior predictions of genetic merit.

Shrinking of EPD range.  You will notice a reduction in the range of EPDs for most traits.  The IGS evaluation team tested the statistical veracity of the reduction and it has proven to be in line with expectations based on the genetic variation in the population.

Improved use of genomics.  With the switch to the BOLT software, IGS will use single-step genomic evaluation on all EPDs. Single-step uses DNA markers, pedigree information, and phenotypic data simultaneously in the prediction of EPDs. Previously, molecular breeding values (MBVs) were calculated from the genomic information and those MBVs were blended in a separate procedure into the EPD predictions. The single-step method squeezes more information from the DNA markers than the previous approach allowed. Additionally, with single-step, the genomic information will not only enhance each EPD for the genotyped animals but also will be used in the EPD estimates of relatives.

The table below shows how many progeny records it takes for an animal without genomics to have the same BIF accuracy as the young animal with genomics (but no progeny).  In other words, EPD on a genotyped 1-month-old calf will be as accurate as an animal with birth weights on 21 calves, weaning weights on 22 calves, etc.  The carcass traits represent actual carcass records, not ultrasound records.   You may notice the maternal calving ease gets the least boost from genomics. This is due in part to such few females being genotyped.

CE 15   STAY 25
MCE 3   CW 6
BW 21   MRB 8
WW 22   REA 5
YW 24   FAT 6
MLK 18   DOC 19

It is important to note, continued collection of phenotypic records remains a vital part of genetic predictions.  DNA testing will never replace the need to record and submit phenotypes.

It is well established that DNA markers vary greatly in their effect on traits — ranging from large to virtually no impact. To leverage this biological fact in a statistically advantageous manner, the BOLT single-step method only uses markers that have a meaningful impact on the traits of interest, while ignoring those that have little to no effect. Research has shown that by using this approach, BOLT reduces statistical “noise” and thereby increases the accuracy of the EPD prediction compared to other single-step methods.

More accurate accuracy.  In the previous IGS evaluation platform and all others in existence other than BOLT, the calculation of the accuracy associated with each EPD is achieved through “approximation” methods. It has long been known these methods are a less than optimal approach to the calculation of accuracy — tending to overestimate accuracy. By employing unique computing strategies that leverage both software and hardware efficiencies, BOLT performs what was previously unthinkable — utilizing a sampling methodology to calculate what is essentially true accuracy. Unlike approximated accuracies, BOLT-derived accuracies will result in predicted movements associated with possible change holding true over time. This is not the case with the previous IGS software or any other system currently in existence.

While the IGS evaluation team and partners are excited to release this new chapter in genetic evaluation, the new genetic evaluation system will only realize its true potential if the selection is made using its EPD and index values.  Hands down, there is no better (more accurate) way to select for quantitative traits than an EPD. Economic indexes predict net profit by weighing the EPD for economically relevant traits coupled with economic estimates. To compete with other protein sources, it is imperative that the beef industry adopts the best science and technology to make better breeding selection decisions.             

Please note, each IGS breed association has the latitude to publish the BOLT generated EPDs when the timing is right for their association.  


For more information about the IGS Multi-breed Genetic Evaluation powered by BOLT, go to   

What to expect with the new IGS Multi-breed Genetic Evaluation powered by BOLT

Frequently Asked Questions

Validation of the new EPDs

Value of DNA tests

The IGS Multi-breed Stayability 


The new genetic evaluation, Multi-breed Genetic Evaluation powered by BOLT, offers groundbreaking advances in the prediction of EPDs for the IGS group. Here are some frequently asked questions and answers to help you better understand Multi-breed Single-step.

1. What are the key features of the Multi-breed Genetic Evaluation powered by BOLT?

• Faster and more automated system allowing for frequent genetic evaluations.

• Improved use of genomic data.

• Improved methodology for predictions of all traits.

• More accurate accuracy.

• More flexibility to add additional traits or change methods for future improvements.

 2. How is ASA’s single-step approach different from blending for genomic evaluation?

The blending approach uses separate steps to calculate genomically enhanced EPDs.  This approach requires two steps.  The first step is to estimate the effects of DNA markers through a process called “training” or “calibration”. These effects are then used to calculate molecular breeding values (MBVs) on genotyped animals.  The MBVs are then combined with traditionally calculated EPDs to enhance the accuracy of the traditionally calculated EPDs.  The blending process is only performed on genotyped animals. 

Befitting its name, the single-step approach calculates genomically enhanced EPDs in one step — using DNA, pedigree information, and phenotypes simultaneously. As a result, the DNA information not only improves the accuracy of prediction on genotyped animals, but also on the relatives and contemporaries of the genotyped animals.  In a sense, all animals are genomically enhanced under the single-step approach.

There are also issues inherent in the blending process that are solved with single-step. Similar to the fact that only reporting phenotypes on a selected group of animals in your herd can lead to less informative (and more biased) EPDs with traditional evaluation, problems can exist with blending as it only involves genotyped animals — and genotyped animals tend to be highly selected. However, because single-step includes information from non-genotyped as well as genotyped animals, the issues are corrected.

3. How is the Multi-breed Genetic Evaluation powered by BOLT different than other single-step models used in other genetic evaluations?

It is well established that DNA markers vary greatly in their effect on traits — ranging from a large to no impact. To leverage this biological fact in a statistically advantageous manner, the BOLT single-step method only utilizes markers that have a meaningful impact on the traits of interest, while ignoring those that have little to no effect. By using this approach, BOLT reduces the statistical “noise” and thereby increases the accuracy of prediction. By circumventing the “noise,” BOLT-generated EPDs tend to be more accurate than EPDs generated by organizations that are relegated to using all markers in their single-step evaluation.

4. How many DNA markers are being used?

The Multi-breed Genetic Evaluation powered by BOLT uses a subset of weighted markers based on a research study performed by Drs. Mahdi Saatchi and Dorian Garrick, while they were scientists at Iowa State University. Drs. Saatchi and Garrick first used the 50,000 markers to determine a subset of weighted markers that are highly associated with economically relevant traits in beef cattle with consistent effects across breeds. Because the IGS evaluation is for multiple breeds, it is important to remove markers with inconsistent effects or no effects in different breeds.

The Saatchi and Garrick research also found that utilizing genotypes on animals of multiple breeds consistently increased the accuracy of prediction within a particular breed when compared to limiting DNA utilization to only animals of a particular breed.

 5. Why are some traits influenced by markers and others are not?

The genetic architectures of various traits are different. Some are controlled by few genes with large effects and some are controlled by many small effects genes. In the current DNA profilers, there are some markers with high correlations with corresponding genes for some traits and low correlations with others. That’s why we see the different DNA added values for different traits. It is hard to change the genetic architecture of a trait. But, new DNA profilers or future technologies may help to improve the value of DNA information for such traits.   Furthermore, some maternal traits, like Maternal Calving Ease and Milk, are difficult to predict with genomics because there are so few females genotyped. Increasing the number of cows and heifers genotyped will improve the ability to use genomics to predict maternal traits.

6. Will genomic testing replace the need to submit phenotype records?

No, reporting actual records is critical. The value of genomic predictions increases as the amount of phenotypic information increases. Furthermore, at this point, animals cannot achieve high accuracy with genomic data alone. High accuracy EPDs are only achievable by collecting many phenotypic records on offspring.

7. How do we know predictions via BOLT are better than the previous system (Cornell software)?

The IGS evaluation team has conducted a series of validations to compare the BOLT system to the Cornell system. BOLT-derived EPDs had higher correlations to birth, weaning and yearling weights (0.34, 0.29, and 0.26, respectively) than the Cornell derived EPDs (0.27, 0.19, and 0.20, respectively). Furthermore, there was a larger difference in average progeny performance (birth, weaning, and yearling) of the top 1% compared to the bottom 1% animals in the BOLT derived EPDs compared to the Cornell calculated EPDs. Both validations suggest the BOLT EPDs align better with the actual phenotypes than the Cornell EPDs.

8. Why do some animals have substantial changes in their indexes?

Though the correlations between the previous (Cornell derived) EPDs/indexes and the BOLT derived EPDs/indexes are relatively strong, there will be some animals that happen to move in a consistently favorable or unfavorable direction in a number of EPDs. Because indexes are comprised of several EPDs, even though movement in individual EPDs may be considered small, movement in the same direction across EPDs may yield sizable movements in the index value. This is particularly true for animals that have consistent movement in traits that are drivers of a particular index. Though in a large population like ours we would expect to see several animals with substantial index movement, these animals will be the exception to the rule.

9. How does BOLT improve our calculation of accuracy?

“True” accuracy can be thought of as the gold standard of accuracy. It is statistically unbiased, and therefore the ultimate measure of accuracy. True accuracy is the accuracy resulting from direct calculation. Unfortunately, even with the massively powerful computing capacity now in existence, the direct calculation of accuracy is not possible on datasets the size of ours. Because we cannot calculate accuracy directly, other approaches to accuracy calculation have been developed.

In our Cornell evaluation platform and all others in existence other than BOLT, the calculation of the accuracy associated with each EPD is achieved through “approximation” methods. It has long been known these methods are a very crude approach to the calculation of accuracy — tending to overestimate accuracy.

Another approach to the calculation of accuracy is via “sampling” methodology. Sampling is shown to be a more accurate predictor of accuracy. In fact, the results of this method were reported to be virtually identical to true accuracy. Unfortunately, due to its computationally intense nature, sampling has long been thought an infeasible approach to the calculation of accuracy on large databases.

BOLT, however, has changed the landscape in this area. By employing unique computing strategies that leverage both software and hardware efficiencies, BOLT performs what was previously unthinkable — utilizing a sampling methodology to calculate what is essentially true accuracy.

Because BOLT can calculate true accuracy, we can put more confidence in our accuracy metrics. Put another way, unlike with approximation, we can count on the predicted movements associated with possible change holding true over time. This was not the case with our Cornell system nor any other system in existence.

10. Why do the carcass EPDs generally have an increase in accuracy with BOLT while this is not a case for other traits?

You will notice that while the Multi-breed Genetic Evaluation powered by BOLT will generally produce lower accuracies than the Cornell system for growth and calving ease traits, the opposite is true for carcass traits.

One reason behind the differing accuracy outcomes is several years ago ASA staff developed a way to temper inflated accuracies in the Cornell carcass evaluation. Unfortunately, this was not possible for growth traits.

Another reason is that the Cornell system only used the carcass and its corresponding ultrasound trait (e.g., marbling score and IMF) to predict carcass EPDs, while records on several additional correlated traits are leveraged with the BOLT system.

A new feature of the BOLT evaluation is a new approach to the calculation of Carcass Weight EPDs. Due to limitations, our previous Carcass Weight EPDs did not incorporate actual carcass weights. They were predicted through an index of birth, weaning, and yearling weights. Besides using prior growth records (weaning, post weaning), the new approach also includes actual carcass weights. This feature will undoubtedly lead to a more accurate prediction of carcass weight.

11. What can I do to improve the predictions on my herd?

Whole Herd Reporting — If you haven’t already, you should consider enrolling your entire herd with a breed association total herd reporting program as it offers the most complete picture of the genetics involved in your herd.

Proper contemporary groups — It is important for the genetic evaluation that you group, to the best of your ability, animals that were treated uniformly. Proper reporting of contemporary groups ensures better predictions for all.         

Take data collection and reporting seriously — Phenotypes are the fuel that drives the genetic evaluation.  Take pride in collecting accurate data. If possible, try to collect additional phenotypes like mature cow weight, cow body condition score, feed intake, and carcass data.           

Use genomics — DNA testing adds more information to what we know about an animal.  The more genotypes we collect, the better we can predict DNA-tested animals in the future. Also, the more relatives genotyped, the better we can predict their relatives in future generations. Therefore, to ensure your bloodlines are well represented in the predictions, genotype your animals. 

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DNA profiles provide additional information about the genetic merit of a DNA-tested animal and increase the accuracy of EPDs, which are called Genomic Enhanced EPD or GE-EPDs. In the IGS Single-step process, the DNA marker genotypes are directly incorporated into the genetic evaluation along with the phenotypes (performance data) and the pedigree. As a result, the DNA information has an impact not only on the genotyped individual but also on all the relatives of that genotyped individual. This allows for the DNA information to improve the accuracy of non-genotyped relatives. To measure the impact of DNA information on accuracies of GE-EPDs in the IGS Single-step genetic evaluations, we compared the average BIF accuracies of GE-EPDs of DNA-tested young animals (born in 2016 with no progeny) to the average BIF accuracies of nongenotyped sires born in 2010-2014. Only sires with non-genotyped calves were used for this comparison. We found that the average BIF accuracy of GE-EPD for a DNA tested young animal is equivalent to the average BIF accuracy of a non-genotyped sire with 21, 22, and 24 calves with observed phenotypes for birth, weaning, and yearling weights, respectively (Figure 1, where a horizontal line cross a curve for a specific trait (e.g. red line and blue curve cross each other at the data point correspond to y(accuracy)=0.46) and x(progeny)=21 for birth weight)). The progeny equivalent (PE) for direct calving ease was 15 and it was only 3 for total maternal calving ease due to limited genotypes on cows. The PE for milk and stayability were 18 and 25, respectively (Figure 1). 


The Multi-breed Evaluation powered by BOLT is a breakthrough in GE-EPD accuracy improvement. Enabling technologies such as BOLT software will allow for even faster genetic progress with more accurate EPDs earlier in an animal’s life. We (IGS) are dedicated to using the best available technology to deliver more accurate GE-EPDs to our members so they have the best tools available for their selection decisions.