Functional Longevity
The cow is the foundation of your herd. Her ability to produce and raise a calf year over year creates consistency in our operations and in turn increased value.
A Step Forward for Maternal Selection Tools
The American Angus Association will be releasing three new EPDs aimed at maternal traits.
Measuring Longevity
The functional longevity (FL) EPD was released in May 2025.
What is the purpose?
The Functional Longevity (FL) EPD predicts the number of calves a sire’s daughter is expected to produce by 6 years of age compared to other sires in the population.
How is the trait expressed?
The unit of the trait is the number of calves produced by 6 years of age, with a higher EPD meaning that on average sires’ daughters are predicted to produce more calves by 6 years of age, compared to a lower EPD.
Despite being a little counterintuitive to have the number of calves expressed with decimals, breeders should focus on differences among sires and the directional change of selection.
Contribute Herd Data
Breeders can help strengthen the data backing the FL EPD by participating in AHIR’s Inventory Reporting program.
New Maternal Tools, Annual Updates | WEBINAR - May 23, 2025
FL EPD FAQs
Data within the whole herd reporting program, Inventory Reporting, laid the foundation for this trait. Calving and culling records since 1990 outside of the Inventory Reporting program are also being used in the evaluation. In the genetic evaluation, data from females between 2 and 10 years of age is utilized; females must calve around two years of age to enter the evaluation. Also included are phenotypes from the Canadian Angus Association.
Breeders are encouraged to record and submit breeding, calving and culling records on all cows for as long as they stay in their herd, as this data is valuable for management and studying maternal characteristics.
Participation in Inventory Reporting is the best way to contribute calving and culling records for the FL trait. Ideally, in the future the functional longevity model will be able to leverage only records and data from herds inside of Inventory Reporting, which will continue to add accuracy to this evaluation.
Primarily spring calving herds should enroll in Inventory Reporting November 1 – January 15. Primarily fall calving herds should enroll May 1 – July 15.
The heritability estimate of FL is 0.10.
Yes, Functional Longevity is one of twelve traits included in the Maternal Weaned Calf Value ($M). More information on how FL is incorporated into $M is available on the $Value Definitions page.
