Page 4 - Riverlee 2020 v2

EBV’S EXPLAINED

CALVING EASE: DIR - Indicates how easily this and for dam age. This EBV is the best single
bull’s progeny are likely to be born estimate of an animal’s genetic merit for growth
beyond yearling age.
DTRS - Indicates how easily this bull’s
daughters are likely to calve. More positive MV - Maternal Value EBV is an index of the
EBVs indicate easier calving. EBVs for the 200-Day Growth and 200-Day Milk,
and is calculated by the following formulae: For
BIRTH: BWT - Birth Weight EBV (kg) is based
1
1
sires: MV = /2 Milk EBV + /4 200-Day Growth
on the measured birth weight of animals,
1
EBV. For dams: MV = Milk EBV + /2 200-Day
adjusted for dam age. The lower the value the
Growth EBV.
lighter the calf at birth and lower the likelihood
of a difficult birth. This is particularly important MCW - Mature Cow Weight is an estimate of
when selecting sires for use over heifers. the genetic difference in cow weight between
animals at five years of age.MCW EBVs for
FERTILITY: SS - Scrotal Size (cm) is an
sires are based on weights recorded on their
indicator of male fertility in regards to semen
daughters. Smaller or more moderate MCW
quality and quantity. Higher (positive) EBVs
EBVs are generally more favourable as they
indicate higher fertility. SS is also positively
indicate more efficient cows requiring less feed
associated with female fertility.
for maintenance.
GROWTH: Milk - 200-Day Milk EBV (kg) is an
CARCASE: CWT - Carcase Weight EBV (kg)
estimate of an animal’s milking ability. For sires,
estimates the genetic difference in carcase
this EBV is indicative of their daugthter’s milking
weight at a standard age of 650 days. More
ability as it affects the 200 day weight of their
positive EBVs indicate heavier carcases at 650
calves.
days of age.
200 - 200-Day Growth EBV (kg) is calculated
EMA - Eye Muscle Area EBV (CM2) Estimates
from the weight of animals taken between 80
genetic differences in eye muscle area at the
and 300 days of age. Values are adjusted to
12/13th rib site of a 300kg dressed carcase.
200 days and for dam age. This EBV is the best
More positive EBVs indicate better muscling on
single estimate of an animal’s genetic merit for
animals.
growth to early ages.
RIB - Rib Fat EBV (mm) estimates the genetic
400 - 400-Day Weight EBV (kg) is calculated
differences in fat depth at the 12/13th rib in a
from the weight of progeny taken between 301
300kg dressed carcase. More positive EBVs
and 500 days of age, adjusted to 400 days
indicate more subcutaneous fat and earlier
and for dam age. This EBV is the best single
maturity.
estimate of an animal’s genetic merit for yearling
weight. RUMP - Rump Fat EBV (mm) estimates the
genetic differences in fat depth at the P8 site
600 - 600-Day Weight EBV (kg) is calculated
on a 300kg dressed carcase. More positive
from the weight of progeny taken between 501
EBVs indicate more subcutaneous fat and
and 900 days of age, adjusted to 600 days
2 - RIVERLEE HEREFORD BULL SALE