Page 77 - Earnscleugh 2021 Catalogue eBook

INDEX DESCRIPTIONS Genetic Selection of bulls using only the SRI tool will on average over
time develop a cow herd with the following:
• Improved weaning rate through increased fertility and easier calving
The following three graphs reflects the relative change if the New Zealand
Angus Published Sires (at the Mid-August 2020 TransTasman Angus • A slowly decreasing cow size, milk and slowly increasing
Cattle Evaluation) were ranked on this selection index and the top 10% body condition
were used within a breeding program. Given that the Published Sires are • Progeny will be prime at a younger age for slaughter
the sires of the next generation(s) of New Zealand Angus cattle and have
more highly accurate EBVs (due to having progeny) than the average These characteristics are ideal for an environment where the herd is
animal in the database, these graphs represent the approximate selection exposed to prolonged seasonal feed deficits and feeding supplement
response one would expect to see in the breed from using this index. is unlikely.

Self Replacing Index (SRI) Checking individual EBV’s relevant to your herd is advised.

New Zealand Angus Self-Replacing Index - Predicted Response Angus Pure Index (API)

Expected Change in Individual Traits Expected Change in Individual Traits
New Zealand Angus AngusPure Index - Predicted Response

CEd CEm GL BW 200W 400W 600W MCW Milk SS DC Cwt EMA Rib Rump RBY IMF

Above the 0 line (X axis) selects for more positive numbers and below the line GL SS
selects for more negative numbers. For some traits (e.g. growth), a positive response CEd CEm BW 200W 400W 600W MCW Milk DC Cwt EMA Rib Rump RBY IMF
is desirable and for others (e.g. days to calving), a negative response is desirable.
Above the 0 line (X axis) selects for more positive numbers and below the line selects
for more negative numbers. For some traits (e.g. growth), a positive response is
desirable and for others (e.g. days to calving), a negative response is desirable.

Earnscleugh 36th Annual Sale 75