The Heavy Grass Index estimates the genetic differences between animals in net profitability per cow joined in a commercial self replacing herd targeting pasture finished steers.
Steers are assumed to be slaughtered at 620 kg live weight (340 kg carcase weight with 12 mm P8 fat depth) at 22 months of age.
Daughters are retained for breeding and therefore maternal traits are of importance. Emphasis has been placed on eating quality and tenderness to favour animals that are suited to MSA requirements.
The graph below shows the emphasis that has been placed on each trait group in the Heavy Grass Index.
The following table shows the indicative change in traits after one generation if producers select animals using the Heavy Grass Index.
The indicative response reflects the change if the Angus Published Sires (at the November 2014 Angus GROUP BREEDPLAN analysis) were ranked on this selection index and the Top 10% selected for use within a breeding program. The response will differ if a different group of animals was available for selection and/or a different selection intensity was applied.