Page 7 - Glenside 2020
P. 7

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.
      Days to Calving EBV (days) indicates the fertility of the daughters of the sire.  It is the time
      interval between the day when the female is first exposed to a bull in a paddock mating to the
      day when she subsequently calves.  A negative EBV for days to calving indicates a shorter interval
      from bull-in date to calving and therefore higher fertility.
      Carcase Weight EBV (kg) is based on abattoir carcase records and is an indicator of the genetic
      differences in carcase weight at the standard age of 650 days.
      Eye Muscle Area EBV (sq cm) is calculated from measurements from live animal ultrasound
      scans and from abattoir carcase data, adjusted to a standard 300 kg carcase.  This EBV estimates
      genetic differences in eye muscle area at the 12/13th rib site of a 300 kg dressed carcase.  More
      positive EBVs indicate better muscling on animals.  Sires with relatively higher Eye Muscle Area
      EBVs are expected to produce better muscled and higher percentage yielding progeny at the
      same carcase weight than will sires with lower Eye Muscle Area EBVs.
      Rib Fat and Rump Fat EBVs (mm) are calculated from measurements of subcutaneous fat depth
      at the 12/13 rib site and the P8 rump site (from live animal ultrasound scans and from abattoir
      carcases) and are adjusted to a standard 300 kg carcase.  These EBVs are indicators of the genetic


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