INDEXES

AngusNZ currently has three selection indexes calculated to describe different production/market scenarios that are specific to New Zealand conditions. These are:

•  Self-Replacing

•  AngusPure; and 

• Heifer/Dairy Terminal.

Index values are reported as EBVs, in units of relative earning capacity ($) for a given market. They reflect both the short-term profit generated by a sire through the sale of his progeny, and the longer-term profit generated by his daughters in a self-replacing cow herd.

Self Replacing Index (SRI)

Estimates the genetic differences between animals in net profitability per cow joined in an example self-replacing commercial herd that targets the production of grass finished steers.  Steers are assumed marketed at approximately 480 kg live weight (265 kg carcase weight and 7 mm fat depth) at approximately 16 months of age. Selected heifers are retained for breeding and the balance marketed at approximately 16 months weighing 415 kgs (230 kg carcase weight and 8 mm fat depth) As some daughters are retained, maternal traits are also of importance

Angus Pure Index (API)

Estimates the genetic differences between animals in net profitability per cow joined in an example self-replacing commercial Angus herd that targets the production of grass finished steers for the AngusPure programme.  Steers are assumed marketed at 530 kg live weight (290 kg carcase weight and 10 mm fat depth) at approximately 20 months of age. Selected heifers are retained for breeding and the balance marketed at approximately 20 months weighing 450 kg (240 kg carcase weight and 10 mm fat depth). A significant premium for carcase quality was assumed and, as some daughters are retained, maternal traits are also of importance.

HDT Index (heifer/dairy terminal)

Estimates the genetic differences between animals in net profitability per female joined in an example herd where all progeny are marketed. All progeny are marketed at approximately 510 kg live weight (280 kg carcase weight and 7 mm fat depth) at approximately 24 months of age. Note that $Index values for individual animals are sensitive to the assumptions used in the BreedObject analysis to calculate the selection index.  More information is available on the weightings used in the Angus New Zealand Selection Indices.