by Elizabeth Dressler, ASA Lead Geneticist
As rapidly as technology is advancing, it might be tempting to think that genetic progress happens automatically, somewhere behind the scenes without you. But that is far from the truth.
While genomics and advanced statistical models used by International Genetic Solutions (IGS) help accelerate genetic progress, those technologies can’t create it on their own. Every genetic evaluation still depends on one thing: phenotypes. The real-world performance of real cattle reported by real cattle producers.
The Role of Phenotypes in Genetic Evaluation
Collectively, member-reported data supplies the genetic evaluation system with the information necessary to calculate expected progeny differences (EPD). Every phenotype reported adds another piece to the puzzle. In other words, EPD aren’t just something that gets delivered back to you. They’re something that you help build.
● Phenotypes are the evidence that power EPD. An EPD is a prediction of future progeny performance. The evidence backing that prediction is the reported performance of relatives, the individual animal itself, eventually its progeny. As more data points are reported, the accuracy of that animal’s EPD improves, meaning you can feel more confident in your breeding decisions.
● Phenotypes anchor genomic predictions. In the era of genomics, phenotypes are even more important. DNA information (SNP markers) are only meaningful if we know what effect they have on actual animal performance. If we stop recording phenotypes today, our genomic “map” will quickly become outdated. We can’t have genomics without phenotypes.
● You can’t improve what you don’t measure. It’s a fundamental law of animal breeding. Without phenotypes, you’re “eyeballing” your way toward genetic progress, which is slow, inefficient, and expensive. To get where you want to go, you must first assess where you are currently.
Data Collection Opportunities this Fall
As fall data collection approaches for spring-calving herds, several traits deserve particular attention due to recent updates and new EPD releases.
Docility
You are likely already planning on reporting weaning weights, but do you plan to report docility scores? While approximately 60% of animals reported to ASA have a weaning weight, only about 20% have a docility score.
The docility evaluation was updated in April 2026 as part of an ongoing series of updates to the IGS genetic evaluation. As more breeders place greater emphasis on docility in selection decisions, reporting docility phenotypes is becoming increasingly important to maintain and improve the accuracy of docility EPD. Information on the docility genetic evaluation updates and how to collect docility scores is available on the ASA website.
A few tips for collecting docility scores:
● It is important to collect docility scores on the entire calf crop at the same time. So, collect a docility score on your entire calf crop this fall during weaning, instead of collecting some at weaning and others at yearling.
● Since docility is subjectively measured, consistency in scoring is very important. The same person should score all animals.
● It is not likely that every single animal should score a 1. There should be some variation in docility scores among a group. Scores should be reported without worry that one poor score will have a drastic negative effect on a sire’s docility EPD.
This fall during weaning, why not also collect and report a docility score in addition to a weaning weight? Let’s see if we can increase the percentage of animals reported to ASA with a docility phenotype from 20% to 25%, 30%, or higher!
Mature weight
Released in February 2026, the mature weight (MW) EPD and cow energy requirement (CER) EPD are new tools that breeders can use to evaluate cow size and efficiency. Collecting and reporting mature cow weights will increase the accuracy of the MW and CER EPD for your animals while continuing to add valuable data to the genetic evaluation.
It is critical that mature cow weights are taken at the right time. Cow weights must be taken within 45 days of weaning a calf. Collecting weights at a standardized point in the production cycle helps reduce non-genetic differences in mature cow weights.
Because the MW EPD is now available for ASA members, this fall is the perfect opportunity to begin submitting MW phenotypes for your cow herd. Submitting MW phenotypes continues to add valuable data, which fuels the genetic evaluation generating this new EPD.
Heifer pregnancy
The release of the heifer pregnancy (HP) EPD this May is another step forward in the development of genetic selection tools for maternal traits. The HP EPD characterizes differences in the percentage of daughters that become pregnant during their first breeding season as heifers. Development of this EPD wouldn’t be possible without the data submitted by ASA breeders through the Total Herd Enrollment (THE) program.
THE is a dam inventory program that facilitates data reporting on complete contemporary groups. If you are not already a participant, more information about the THE program can be found on the ASA website. For spring-calving herds, THE enrollment opens on October 15 for the following spring calving season. It is vitally important that dams are properly enrolled in THE and that productivity and removal codes are used correctly. It is the data submitted through THE that makes it possible to to calculate maternal EPD, including stayability and HP.
This fall, there may be an opportunity to collect one more trait than you have typically done in years past. Breeders committed to the phenotype reporting that fuels the genetic evaluation for 14 high-priority traits are recognized as Performance Advocates. You can check your progress toward earning performance advocacy status on your Herdbook account online.
Genetic progress doesn’t originate in Bozeman, Montana, at ASA’s headquarters. Genetic progress begins on the ranch with the collection and reporting of the critical phenotypes that fuel the genetic evaluation.
