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the lower the likelihood of a difficult birth. This is particularly important when to a bull in a paddock mating to the day when she subsequently calves. A
selecting sires for use over heifers. negative EBV for days to calving indicates a shorter interval from bull-in date
200-Day Growth EBV (kg) is calculated from the weight of progeny taken to calving and therefore higher fertility.
between 80 and 300 days of age. Values are adjusted to 200 days and Carcase Weight EBV (kg) is based on abattoir carcase records and is an
for age of dam. This EBV is the best single estimate of an animal’s genetic indicator of the genetic differences in carcase weight at the standard age
merit for growth to early ages. of 750 days.
400-Day Weight EBV (kg) is calculated from the weight of progeny taken Eye Muscle Area EBV (sq cm) is calculated from measurements from
between 301 and 500 days of age, adjusted to 400 days and for age of live animal ultrasound scans and from abattoir carcase data, adjusted to a
dam. This EBV is the best single estimate of an animal’s genetic merit for standard 400 kg carcase. This EBV estimates genetic differences in eye
yearling weight. muscle area at the 12/13th rib site of a 400 kg dressed carcase. More
600-Day Weight EBV (kg) is calculated from the weight of progeny taken positive EBVs indicate better muscling on animals. Sires with relatively
between 501 and 900 days of age, adjusted to 600 days and for age of higher EMA EBVs are expected to produce better-muscled and higher
dam. This EBV is the best single estimate of an animal’s genetic merit for percentage yielding progeny at the same carcase weight than will sires with
growth beyond yearling age. lower EMA EBVs.
Mature Cow Weight EBV (kg) is based on the cow weight when the calf Rib Fat and Rump Fat EBVs (mm) are calculated from measurements
is weighed for weaning, adjusted to 5 years of age. This EBV is an estimate of subcutaneous fat depth at the 12/13-rib site and the P8 rump site (from
of the genetic difference in cow weight at 5 years of age and is an indicator live animal ultrasound scans and from abattoir carcases) and are adjusted
of growth at later ages and potential feed maintenance requirements of the to a standard 400 kg carcase. These EBVs are indicators of the genetic
females in the breeding herd. Steer breeders wishing to grow animals out differences in fat distribution on a standard 400 kg carcase. Sires with
to a larger weight may also use the Mature Cow Weight EBV. low, or negative, fat EBVs are expected to produce leaner progeny at any
Milk EBV (kg) is an estimate of an animal’s milking ability. For sires, this particular carcase weight than will sires with higher EBVs.
EBV indicates the effect of the daughter’s milking ability, inherited from the Retail Beef Yield EBV (%) indicates genetic differences between animals
sire, on the 200-day weights of her calves. For dams, it indicates her for retail yield percentage in a standard 400 kg carcase. Sires with larger
milking ability. EBVs are expected to produce progeny with higher yielding carcases.
Scrotal Size EBV (cm) is calculated from the circumference of the scrotum Intramuscular Fat EBV (%) is an estimate of the genetic difference in the
taken between 300 and 700 days of age and adjusted to 400 days of age. percentage of intramuscular fat at the 12/13th rib site in a 400 kg carcase.
This EBV is an estimate of an animal’s genetic merit for scrotal size. There Depending on market targets, larger more positive values are generally
is also a small negative correlation with age of puberty in female progeny more favourable.
and therefore selection for increased scrotal size will result in reduced age Docility EBV (%) is an estimate of the genetic differences between
at calving of female progeny. animals in temperament. Docility EBVs are expressed as differences in the
Days to Calving EBV (days) indicates the fertility of the daughters of the percentage of progeny that will be scored with acceptable temperament (ie.
sire. It is the time interval between the day when the female is first exposed either “docile” or “restless”).
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