Page 7 - Tawanui, Aywon, Te Kupe Sale 2021 ebook

Days to Calving EBV (days) indicates the fertility of the daughters of for retail yield percentage in a standard 400 kg carcase. Sires with larger
the sire. It is the time interval between the day when the female is first EBVs are expected to produce progeny with higher yielding carcases.
exposed to a bull in a paddock mating to the day when she subsequently Intramuscular Fat EBV (%) is an estimate of the genetic difference in the
calves. A negative EBV for days to calving indicates a shorter interval from percentage of intramuscular fat at the 12/13th rib site in a 400 kg carcase.
bull-in date to calving and therefore higher fertility.
Depending on market targets, larger more positive values are generally
Carcase Weight EBV (kg) is based on abattoir carcase records and is an more favourable.
indicator of the genetic differences in carcase weight at the standard age Docility EBV (%) is an estimate of the genetic differences between
of 750 days.
animals in temperament. Docility EBVs are expressed as differences in the
Eye Muscle Area EBV (sq cm) is calculated from measurements from live percentage of progeny that will be scored with acceptable temperament
animal ultrasound scans and from abattoir carcase data, adjusted to a (ie. either “docile” or “restless”).
standard 400 kg carcase. This EBV estimates genetic differences in eye
muscle area at the 12/13th rib site of a 400 kg dressed carcase. More SELECTION INDEXES
positive EBVs indicate better muscling on animals. Sires with relatively There are currently three different selection indexes calculated for New
higher EMA EBVs are expected to produce better-muscled and higher Zealand Angus animals. These are Self-Replacing, AngusPure and Heifer/
percentage yielding progeny at the same carcase weight than will sires Dairy Terminal. Each selection index describes a different production/
with lower EMA EBVs. market scenario and relates to a typical commercial herd in New Zealand
Rib Fat and Rump Fat EBVs (mm) are calculated from measurements of that is targeting the following specifications.
subcutaneous fat depth at the 12/13-rib site and the P8 rump site (from Index values are reported as EBVs, in units of relative earning capacity
live animal ultrasound scans and from abattoir carcases) and are adjusted ($’s) for a given market. They reflect both the short-term profit generated
to a standard 400 kg carcase. These EBVs are indicators of the genetic by a sire through the sale of his progeny, and the longer-term profit
differences in fat distribution on a standard 400 kg carcase. Sires with generated by his daughters in a self-replacing cow herd. More information
low, or negative, fat EBVs are expected to produce leaner progeny at any is available on selecting animals using a selection index.
particular carcase weight than will sires with higher EBVs.
The Index values are derived using BreedObject technology.
Retail Beef Yield EBV (%) indicates genetic differences between animals More information is available from the BreedObject web site.
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