Page 6 - Okawa Herefords Catalogue ebook

UNDERSTANDING ESTIMATED BREEDING VALUES (EBV’s)

ESTIMATED BREEDING VALUES (EBVs): The EBV is the best estimate of an animal’s genetic merit for that trait.
CALVING EASE:
DIR- Indicates how easily this bull’s progeny are likely to be born
DTRS- Indicates how easily this bull’s daughters are likely to calve. More positive EBVs indicate easier calving.

BIRTH:
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.
GROWTH:
Milk - 200-Day Milk EBV (kg) is an estimate of an animal’s milking ability. For sires, this EBV is indicative of their daugthter’s milking ability as it affects the 200 day
weight of their calves.

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.
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MV - Maternal Value EBV is an index of the EBVs for the 200-Day Growth and 200-Day Milk, and is calculated by the following formulae: For sires: MV = /2 Milk EBV
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+ /4 200-Day Growth EBV. For dams: MV = Milk EBV + /2 200-Day Growth EBV.
MCW - Mature Cow Weight is an estimate of the genetic difference in cow weight between animals at five years of age. MCW EBVs for sires are based on weights
recorded on their daughters. Smaller or more moderate MCW EBVs are generally more favourable as they indicate more efficient cows requiring less feed for maintenance.
FERTILITY:
SS- Scrotal Size (cm) is an indicator of male fertility in regards to semen quality and quantity. Higher (positive) EBVs indicate higher fertility. SS is also positively
associated with female fertility.
CARCASE:
CWT - Carcase Weight EBV (kg) estimates the genetic difference in carcase weight at a standard age of 650 days. More positive EBVs indicate heavier carcases at
650 days of age.
EMA - Eye Muscle Area EBV (CM ) Estimates genetic differences in eye muscle area at the 12/13th rib site of a 300kg dressed carcase. More positive EBVs indicate
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better muscling on animals.
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