Page 7 - Colvend Catalogue eBook

EBVs Explained

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.

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