Page 7 - Woodbank-Matariki ebook

EBVs are published for a range of traits covering fertility,
calving ease, milking ability, growth, carcase merit and
feed efficiency. When using EBVs to assist in selection
decisions it is important 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.

Woodbank Angus & Matariki Herefords Bull Sale 2021 5