Page 6 - Mokairau Sale Catalogue 2021 ebook

ESTIMATED BREEDING VALUES
(EBVS) EXPLAINED:

HOW TO USE THEM
Group Breedplan calculates predictions of genetic merit called EBVs
for a range of traits on a national across-herd basis. The EBVs are
calculated using information on the animal’s own performance plus
the performance of all known relatives (sire, dam, half sisters and
brothers etc.), the relationship between the traits and the pedigree
lines between animals and between herds.
All EBVs quoted in the catalogue are 2021 New Zealand Hereford
Group Breedplan EBVs and are directly comparable with the EBVs
from other New Zealand Hereford Group Breedplan Herds, but not
other breeds.

HOW ANIMALS ARE RANKED ON EBVS
All EBVs are shown as + or - kg liveweight. Animals are ranked
in comparison to a breed base of 0, derived from historic
performance records for the breed.
HOW TO USE EBVS
The first step is to decide which characteristics are important
in your breeding program, then to select the EBVs which fit the
breeding objectives for your herd. You will need to look for balanced
animals with perhaps more emphasis on some traits than others.
• BWT: Birth Weight EBV (kg) is based on the measured birth weight
of animals, adjusted for dam age. The lower the value the lighter
the calf at birth and lower the likelihood of a difficult birth. This is
particularly important when selecting sires for use over heifers.
• 200: 200-day Growth EBV (kg) is calculated from the weight of
animals taken between 80 and 300 days of age. Values are adjusted
to 200 days and for dam age. This EBV is the best single estimate
of an animal’s genetic merit for growth to early ages.
• 400: 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 dam age. This EBV is the best single estimate of an
animal’s genetic merit for yearling weight.
• 600: 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 dam age. This EBV is the best single estimate of an
animal’s genetic merit for growth beyond yearling age.
• MATURE COW WEIGHT: 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.
6 Mokairau Bull Sale 2021