Page 9 - Peters Angus 2021 Catalogue ebook

days and for age of dam. This EBV is the best single estimate of an
animal’s genetic merit for growth to early ages.
400-Day Weight EBV (kg) is calculated from the weight of progeny
taken between 301 and 500 days of age, adjusted to 400 days and
for age of dam. This EBV is the best single estimate of an animal’s
genetic merit for yearling weight.
600-Day Weight EBV (kg) is calculated from the weight of progeny
taken between 501 and 900 days of age, adjusted to 600 days and
for age of dam. This EBV is the best single estimate of an animal’s
genetic merit for growth beyond yearling age.
Mature Cow Weight EBV (kg) is based on the cow weight when
the calf is weighed for weaning, adjusted to 5 years of age. This EBV
is an estimate of the genetic difference in cow weight at 5 years of
age and is an indicator of growth at later ages and potential feed
maintenance requirements of the females in the breeding herd. Steer
breeders wishing to grow animals out to a larger weight may also use
the Mature Cow Weight EBV.
Milk EBV (kg) is an estimate of an animal’s milking ability. For sires,
this EBV indicates the effect of the daughter’s milking ability, inherited
from the sire, on the 200-day weights of her calves. For dams, it
indicates her milking ability.
Scrotal Size EBV (cm) is calculated from the circumference of the
scrotum taken between 300 and 700 days of age and adjusted to
400 days of age. This EBV is an estimate of an animal’s genetic merit
for scrotal size. There is also a small negative correlation with age
of puberty in female progeny and therefore selection for increased
scrotal size will result in reduced age at calving of female progeny.
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

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