Page 10 - Sudeley Angus ebook

to achieve a balance between the different groups of traits and to
place emphasis on those traits that are important to the particular
herd, markets and environment. One of the advantages of having
a comprehensive range of EBVs is that it is possible to avoid
extremes in particular traits and select for animals with balanced
overall performance.
Calving Ease EBVs (%) are based on calving difficulty scores,
birth weights and gestation length information. More positive
EBVs are favourable and indicate easier calving.
CE % Direct = Direct Calving Ease - The EBV for direct calving
ease indicates the influence of the sire on calving ease in purebred
females calving at two years of age.
CE % Daughters = Daughters’ Calving Ease - The EBV for
daughters’ calving ease indicates how easily that sire’s daughters
will calve at two years of age.
Gestation Length EBV (days) is an estimate of the time from
conception to the birth of the calf and is based on AI and hand
mating records. Lower (negative) GL EBVs indicate shorter
gestation length and therefore easier calving and increased growth
after birth.
Birth Weight EBV (kg) is based on the measured birth weight of
progeny, adjusted for dam age. The lower the value, the lighter the
calf at birth and the lower the likelihood of a difficult birth. This
is particularly important when selecting sires for use over heifers.
200-Day Growth EBV (kg) is calculated from the weight
of progeny taken between 80 and 300 days of age. Values are
adjusted to 200 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,

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