Two new Research Breeding Values (RBVs) are available for Angus cattle evaluation, both for eating quality traits – MSA Marbling Score and Shear Force tenderness measurement.

Research Breeding Values (RBVs) are EBVs under development. They can be utilised in the same manner as EBVs, however they are subject to greater potential change than the EBVs routinely reported in the TransTasman Angus Cattle Evaluation as improvements are made to the analytical models that are used to calculate them, and as additional performance information is collected.

The TransTasman Angus Cattle Evaluation (TACE) is the genetic evaluation program adopted by Angus Australia for Angus and Angus influenced beef cattle. TACE uses Best Linear Unbiased Prediction (BLUP) technology to produce Estimated Breeding Values (EBVs) of recorded cattle for a range of important production traits.

RBVs are produced as part of the development of EBVs for new traits, which enable the refinement of both the performance recording information and the analytical software used in their calculation.

Current Research Breeding Values for Angus include:

• Coat Type
• Mature Cow Body Condition
• Mature Cow Height
• ImmuneDEX
• Shear Force
• MSA Marbling

Shear Force

Shear Force (SF) RBVs provide estimates of genetic differences between animals in objective beef tenderness.

They are calculated from a laboratory assessed beef shear force measurement.

Shear Force EBVs are expressed in kilograms of shear force that are required to pull a mechanical blade through a piece of cooked meat.

Lower, more negative, SF RBVs are more favourable, indicating that less shear force is required, and hence that the meat is more tender.

MSA Marbling

MSA Marbling Score (MMS) RBVs are estimates of genetic difference between animals in MSA marbling score at the 12th/13th rib grading site on a 400kg steer carcase.

MMS RBVs are calculated from MSA marbling scores taken by an accredited carcase grader.

The RBVs are expressed in MSA marbling score units.

Higher, more positive MMS RBVs indicate the animal is expected to produce progeny with higher marbling scores in a 400kg steer carcase.

Source: Angus Australia