Angus breeders and their commercial customers operate in a variety of different environments and management systems. The data collected across these different management systems comes together in the weekly evaluation to inform genetic selection tools. The capability to utilize phenotypic data for accurate genetic evaluation relies on a few key factors. 

Contemporary groups

Phenotypes are the driving force behind the genetic evaluation. However, the use of phenotypes within the genetic evaluation is heavily dependent on proper contemporary grouping. 

Contemporary groups are groups of animals who have had equal opportunity to perform for a trait. Typically, these are animals of similar age, managed alike and the same sex, although each trait has its own specific contemporary group criteria. 

Phenotypes are influenced by the animal’s genetics and the environment in which it was raised; however only genetics can be passed on. 

In the genetic evaluation, contemporary groups help account for the effect of the environment on the phenotype, so genetic merit can be estimated. Well-designed contemporary groups are the cornerstone of the genetic evaluation and are vital to accurately calculating genetic selection tools.

Connectedness

Phenotypic differences within a contemporary group show how an individual performs compared to those raised within the same environment. But how are those differences compared across different environments? Comparisons across environments (i.e., between contemporary groups) are dependent on the degree at which those groups are genetically connected — referred to as connectedness.

With the phenotypic data collected across herds, expected progeny differences (EPDs) could be calculated with greater accuracy than would be possible with limited connectedness across herds. This not only benefited artificial insemination (AI) sires, but also natural service sires whose progeny were being compared to the progeny of AI sires. During that same board meeting, the National Sire Evaluation program was also approved, which led to the release of the first Sire Evaluation Report in 1974.  

Now, more than 50 years later, the Angus breed is more interconnected than ever. In addition to AI usage, connectedness has also improved with the increased use of embryo transfer technology and the growth in global demand for Angus genetics. As connectedness improves, so does the ability to tie more data together by creating genetic links between animals that are raised across different environments, which consequently adds more information to each individual EPD estimate. Additionally, accounting for connectedness has tremendously improved with genomic technology, which can determine more accurate relationships than traditional pedigree alone.

Collective contribution

Phenotypes are influenced by both the genetics an animal inherits and the environment in which it is raised. With well-structured contemporary groups, the genetic evaluation can more effectively separate genetic merit from environmental influence. Each animal’s phenotype contributes value on its own, but its impact is multiplied when it is connected to individuals exposed to different environmental conditions. 

The strength of the Angus genetic evaluation lies in the collective contribution of breeders working together. As connectedness increases and more high-quality data are submitted, the evaluation becomes more powerful, providing more accurate selection tools that benefit everyone who uses Angus genetics. 

Editor’s note: For more information, please contact the American Angus Association Member Services Department at 816-383-5100.