Page 12 - Mt Possession Angus Catalogue ebook

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 (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

10 Mt Possession Angus Bull Sale 2021