Page 9 - Kincardine 2 Yr Angus Catalogue ebook
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Days to Calving EBV (days) indicates the fertility of the daughters of the sire. It is the time
interval between the day when the female is first exposed to a bull in a paddock mating to
the day when she subsequently calves. A negative EBV for days to calving indicates a shorter
interval from bull-in date to calving and therefore higher fertility.
Carcase Weight EBV (kg) is based on abattoir carcase records and is an indicator of the
genetic differences in carcase weight at the standard age of 750 days.
Eye Muscle Area EBV (sq cm) is calculated from measurements from live animal ultrasound
scans and from abattoir carcase data, adjusted to a 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
positive EBVs indicate better muscling on animals. Sires with relatively higher EMA EBVs
are expected to produce better-muscled and higher percentage yielding progeny at the same
carcase weight than will sires with lower EMA EBVs.
Rib Fat and Rump Fat EBVs (mm) are calculated from measurements of subcutaneous fat
depth at the 12/13-rib site and the P8 rump site (from live animal ultrasound scans and from
abattoir carcases) and are adjusted to a standard 400 kg carcase. These EBVs are indicators
of the genetic differences in fat distribution on a standard 400 kg carcase. Sires with low, or
negative, fat EBVs are expected to produce leaner progeny at any particular carcase weight
than will sires with higher EBVs.
Retail Beef Yield EBV (%) indicates genetic differences between animals for retail yield
percentage in a standard 400 kg carcase. Sires with larger EBVs are expected to produce
progeny with higher yielding carcases.
Intramuscular Fat EBV (%) is an estimate of the genetic difference in the percentage of
intramuscular fat at the 12/13th rib site in a 400 kg carcase. Depending on market targets,
larger more positive values are generally more favourable.
Docility EBV (%) is an estimate of the genetic differences between animals in temperament.
Docility EBVs are expressed as differences in the percentage of progeny that will be scored
with acceptable temperament (ie. either “docile” or “restless”).
Selection Indexes
There are currently three different selection indexes calculated for New Zealand Angus animals.
These are Self-Replacing, AngusPure and Heifer/Dairy Terminal. Each selection index describes
a different production/market scenario and relates to a typical commercial herd in New Zealand
that is targeting the following specifications.
Index values are reported as EBVs, in units of relative earning capacity ($’s) 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. More information
is available on selecting animals using a selection index. The Index values are derived using
BreedObject technology
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