Canadian Angus Association

Functional Longevity Genetic Evaluation

Functional Longevity Research Genetic Evaluation (FL EPD)

Cow longevity, fertility, and productivity are critical factors towards profitable and sustainable beef production. Your Canadian Angus Association, in partnership with the American Angus Association, have worked with Angus Genetics Inc. (AGI) to develop a genetic evaluation that describes the probability of a sire’s daughters staying in the herd and producing a calf every year. The trait, Functional Longevity (because longevity is meaningless unless there a calf associated with staying in the herd), is an advancement on previous stayability models where females were only assessed as to whether they stayed in the herd. The development of the genetic evaluation for Functional Longevity (FL) was based on whole herd reporting data, which Canadian Angus members have painstakingly provided for decades. Complete herd inventory submissions were critical towards the successful development of this genetic evaluation.

As a result of these records, we are able to provide Canadian Angus members with some preliminary results from our research genetic evaluation for Functional Longevity (FL EPDs). FL EPDs predict the number of calves a sire’s daughter is expected to produce by 6 years of age compared to other sires’ daughters in the population.

The unit of the FL EPD is the number of calves produced by 6 years of age. A higher EPD means that on average, a sire’s daughters are predicted to produce more calves by 6 years of age compared to a lower EPD.

For example, if Sire A has an FL EPD of 1.5 and Sire B has an FL EPD of 0.5, on average, the daughters of Sire A are expected to produce one more calf by age 6 compared to Sire B’s daughters.

The trait is lowly heritable at 0.09 or 9% meaning that 9% of the variation we see in cows staying and producing in herds at 6 years of age is due to genetics. The Canadian breed average for the Functional Longevity research-based evaluation is 0.98, ranging from 0.61 to 1.35, with a standard deviation of 0.07. This spread should widen as the genetic evaluation is incorporated into producers’ breeding programs.

Why publish a research genetic evaluation for Functional Longevity? This research evaluation is our opportunity to provide members who submit whole herd information with FL EPDs on their own animals for in-herd use and validation and also provides an opportunity to answer your questions about this genetic evaluation. Publishing the research evaluation provides an opportunity to verify the FL EPDs according to our members’ experience with different genetics as well.

For more information, please contact our staff geneticist Dr. Kajal Latimer at or 403-537-5604.