Genetics to Stay Longer, Udderly Beautiful
Angus releases three new maternal EPDs to help predict longevity and udder quality in Angus cattle.
June 3, 2025
Cows that flunk out early, failing to produce enough calves to cover their costs, can drain profitability. The American Angus Association released three new maternal expected progeny differences (EPDs) this May to help select females — and the bulls to produce them — that will have better udders and produce in the herd longer.
Users of Angus genetics can now utilize the functional longevity (FL), teat size (Teat) and udder suspension (UDDR) EPDs developed by Angus Genetics Inc. (AGI) to help make selection decisions. The three new EPDs were also incorporated into both the Maternal Weaned Calf Value Index ($M) and the Combined Value Index ($C), further refining the characterization of maternal function within those indexes.
“The teat size and shape is so important to us as we calve.”
— Janice Nikkel
Maternal cornerstone
The cow is a cornerstone of any successful operation, and Angus females have proven themselves to be reliable, consistent producers. Their merit is reflected in the population of the U.S. cow herd, which is now more than 80% Angus-influenced. Producers have spent years selecting cattle with good maternal characteristics, as well as growth and carcass traits.
“We’ve always bred for cows,” says Mark Nikkel, owner of Mill Brae Ranch since 2018, and herd manager since 1987. “The bulls pay the bills and keep you in business, but there’s got to be a cow first.”
Guided by that principle, Mark and his wife, Janice, began tracking udder quality on the Maple Hill, Kan., operation more than a decade before the Association formalized a scoring guide; and, prior to that, their selection was done anecdotally.
The current Association scoring system was established in 2021, based on guidelines set by the Beef Improvement Federation. It uses scores from 1 to 9 to characterize both teat size and udder suspension. Scores are collected on dams within 24 hours of birth and can be submitted along with data collected on the calf.
“The teat size and shape is so important to us as we calve. ... Age plays into this as well; that’s where the longevity piece comes in,” Janice explains. “When you have a 3-year-old that shows a decline in udder quality, they’re not going to be here very long. Now we’ve wasted a lot of time and money to produce this high-quality animal to send her down the road, and that makes no sense.”
This is a sentiment Esther Tarpoff, director of performance programs for the Association, hears often. In the cattle business, seedstock producers and commercial cow-calf operators play the long game. It’s important to have confidence that today’s selections are based on the best information available to help ensure a profitable outcome in later breeding cycles.
“We’re excited to move these EPDs into full production, enabling weekly predictions of the traits,” Tarpoff says. “This advancement enhances the ability of Association members and, more importantly, their commercial cow-calf customers to select for cow survivability and lifetime productivity — an area that has been missing from the Angus genetic toolkit until now.”
“When you have a 3-year-old that shows a decline in udder quality, they’re not going to be here very long. Now we’ve wasted a lot of time and money to produce this high-quality animal to send her down the road, and that makes no sense.” — Janice Nikkel
Following a dispersal of the original Mill Brae herd in 2018 and a brief break from raising seedstock, Mark and Janice made the decision to purchase back several foundational females that were still in production at other operations to reestablish their registered Angus operation. They made the commitment, at that time, to enroll in the Association’s Inventory Reporting program to earn MaternalPlus® distinction, and submit their historic teat and udder data. The two initiatives gave the Nikkels access to the three research EPDs.
“I used those spreadsheets, and I know they are just research EPDs; but, I am so thankful I had access to them,” Janice says. “If an individual bull that we were looking at didn’t score well in the longevity, teat and udder categories, he went off the list ... It takes too long to overcome [challenges with] those types of traits.”
The FL EPD aims at improving the cow herd by increasing the number of calves a female can produce over her lifetime. The Inventory Reporting program and the commitment made by enrolled members was crucial to the ability to characterize this trait. As a whole-herd reporting system, Inventory Reporting and its second tier, MaternalPlus, tell a more complete story about a herd and its females. Every year, each female is reported to have a calf, a reason code for not having one or a reason code for culling.
This allows for more complete data to be quantified and used to predict the number of calves a female (or daughters of a sire) is expected to produce by 6 years of age. With the production release of this EPD, all registered Angus cattle with either a genotype or phenotype on file will have an FL EPD.
“With the use of technology like genomics, we are turning generation intervals faster than ever,” says Kelli Retallick-Riley, AGI president. “Traits like udder quality or lifetime production records that need to be collected on sires’ daughters take time; producers will be able to utilize the FL, Teat and UDDR EPDs as risk mitigation tools, especially in today’s fast-paced genetic landscape where an AI (artificial insemination) sire may no longer be actively marketed by the time his daughters reach full production.”
Along with the release of the three new EPDs, $M has been updated to include the new traits. As new traits are incorporated into a $Value, economic weights are reallocated across both existing and newly introduced EPDs. Despite the inclusion of additional traits to $M, correlations remain above 0.90. This is because $M already had several other traits considered in its calculations, and the addition of the new EPDs allows for a refinement of the index — not an overhaul of the economic model. However, individual animals may experience notable re-ranking depending on their performance in specific traits.
As part of the makeup of $C, the updates to $M will also be reflected in the $C index with an even greater correlation of 0.98. Producers can learn more about the research backing the Functional Longevity, Teat Size and Udder Suspension EPDs and Dollar Values on Angus.org. Additional details about the annual updates are available in this Angus University video.
Annual updates released
The new EPDs were released alongside annual updates to the genetic evaluation and the economic assumptions used to calculate the Association’s suite of dollar value indexes ($Values).
Heifer Pregnancy (HP) updates. Last May, adjustments to the contemporary group guidelines for HP were completed, allowing the EPD to better account for environmental factors. This year, genetic variance components were updated using the current phenotypic database and more efficient methods for predicting variance components in binary traits.
The heritability of HP moved from 0.15 to 0.07 because models now better account for environmental factors, which redistributed the variance within the population. The correlation between the new EPD and the previous remains high at 0.98, which means there was not a significant reranking of animals, although producers will notice the overall spread of the HP EPD is smaller and a slight reduction in individual EPD accuracy. This is a result of reduced heritability.
Feed intake model updates. This 2025 update comes as the result of an extensive research and testing effort. To improve efficiency and address the complexity of the model used to predict feed efficiency selection tools, dry-matter intake (DMI) and residual average daily gain (RADG) EPDs, this update refines the contemporary groups, introduces animal age, and reestimates variance components and heritability.
The biggest change for producers to keep in mind is the contemporary group. Research found age variation among contemporary groups and environment prior to the feed intake test period have a significant effect on performance. Breeders collecting feed efficiency records will need to have at least two animals from the same birth herd, year and season in a group to have the records included in the evaluation. Single-animal contemporary groups will be excluded. Prediction accuracy will increase by 9.2% with the update.
Correlation on EPDs from the previous model was high (≥0.96); however, producers may see individual changes to EPDs and accuracy, as well as minor reranking. Producers will see minimal movement in the indexes that consider feed efficiency, such as Beef Value ($B), but will potentially see slightly more changes in $B’s subindex, Feedlot Value ($F).
Economic assumptions updated. Year-to-year changes in the cost of inputs like feed can affect management decisions. $Values use a seven-year rolling average to account for economic variation. The cost and revenue data, sourced from CattleFax, shows a continued rise in both ration cost and weaned-calf sale prices. As of May 2025, feed cost was up $13 to $237, while weaned-steer calf prices averaged $203 per hundredweight (cwt.), up $21. Respectively, heifer calves averaged $183 with a price jump a few dollars shy of the steer increase. Because of a similar increase across the board, the new economic assumptions had little effect on the $Values. A detailed breakdown of the economic assumptions can be found on Angus.org.
Genomic score updates. Annual genomic score updates, which have typically coincided with the annual update and the release of the 2025 Fall Sire Evaluation Report, will be released June 27 and will include genomic scores for the three newly released EPDs.
Resources
The following resources are available to help users of Angus genetics leverage the tools and programs available through the Association. Those with additional questions are encouraged to reach out to the Member Services team by phone at 816-383-5100, email (angus@angus.org) or through the message center in their AAA Login.
Research backing EPD development:
Collecting & Submitting Data
Angus Beef Bulletin EXTRA, Vol. 17, No. 6-A
Topics: EPDs , Genetics , Management , Reproduction , Selection
Publication: Angus Beef Bulletin
Related Content
Current Angus Beef Bulletin
The April issue has a “Focus On Females,” including a special advertising section devoted to herds intent on providing the female foundation.
