Page 11 - Waigroup Pinebank Pinehill Angus 2021 Catalogue 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.
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.
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