Wagyu BREEDPLAN EBV’s

WAGYU BREEDPLAN EBVS EXPLAINED

ESTIMATED BREEDING VALUES (EBVS)

An animal’s breeding value is its genetic merit, half of which will be passed on to its progeny. While we will never know the exact breeding value, for performance traits it is possible to make good estimates. These are called Estimated Breeding Values (EBVs). The EBV is therefore the best estimate of an animal’s genetic merit for that trait. EBVs are expressed as the difference between an individual animal’s genetics and the genetic base to which the animal is compared.

ACCURACY

An accuracy value is presented with every EBV and gives an indication of the amount of information that has been used in the calculation of that EBV. The higher the accuracy, the lower the likelihood of change in the animal’s EBV as more information is analysed for that animal or its relatives.

Accuracy Range                  Interpretation

o   Less than 50% = Low accuracy and should be considered a preliminary estimate. The EBV could change substantially as more performance information becomes available.

o   50 – 74% = Medium accuracy, usually based on the animal’s own records and pedigree.

o   75 – 90% = Medium-high accuracy and usually includes some progeny information. Becoming a more reliable indicator of the animal’s value as a parent.

o   90% and above = High accuracy. It is unlikely that the EBV will change much with the addition of more progeny data.

BIRTH

  • GL: Gestation Length EBV (days) is based on AI records. Lower (negative) GL EBVs indicate shorter gestation lengths which generally relate to easier calving.
  • BWT: Birth Weight EBV (kg) is based on the measured birth weight of animals. 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 calving at 2 years of age.

GROWTH

  • 200: 200-Day Growth EBV (kg) is calculated from the weight of animals taken between 80 and 300 days of 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. 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.
  • MWT: Mature Cow Weight EBV (kg) is an estimate of the genetic difference in cow weight at 5 years of age. Smaller, or more moderate EBVs are generally more favourable.
  • MILK: 200-Day Milk EBV (kg) is an estimate of an animal’s milking ability. For sires, this EBV is indicative of their daughter’s milking ability as it affects the 200-day weight of their calves.

FERTILITY

  • SS: Scrotal Size EBV (cm) is an indicator of male fertility in regards to semen quality and quantity. Higher (positive) EBVs indicate higher fertility. There is also a favourable genetic relationship with age of puberty in female progeny.

CARCASE

  • EMA: The EMA EBV (cm2) estimates genetic differences in eye muscle area at the 12/13th rib site of a 300kg dressed carcase. More positive EBVs indicate better muscling on animals.
  • Rib Fat: The Rib Fat EBV (mm) estimates the genetic differences in fat depth at the 12/13th rib in a 300kg dressed carcase. More positive EBVs indicate more subcutaneous fat and earlier maturity.
  • Rump Fat: The Rump Fat EBV (mm) estimates the genetic differences in fat depth at the P8 site of a 300kg dressed carcase. More positive EBVs indicate more subcutaneous fat and earlier maturity.
  • RBY: The RBY% EBV (%) represents total (boned out) meat yield as a percentage of a 300kg dressed carcase. A more positive EBV indicates higher percentage yield for the 300kg carcase size.
  • IMF: The Intramuscular Fat (IMF) EBV (%) is an estimate of the genetic difference in the percentage of intra-muscular fat at the 12/13th rib site in a 300kg carcase.

Note There is currently more than 5,000 Fullblood abattoir carcase records used in the Wagyu BREEDLAN carcase analysis with additional records added on a regular basis. The analysis also use Rib and Rump Fat and Eye Muscle Area ultrasound scanning records which are collected on live animals between 300 to 800 days of age. The genetic correlation between ultrasound Intramuscular Fat (IMF) percentage and carcase marble score were found to be very low and not useful. Therefore; IMF is not included in the analysis to determine Marble Score EBVs.

Ultrasound scanning must be done by an accredited technician, click here for a list of accredited technicians.

SELECTION INDEX:

  • Fullblood Feedlot Index: Estimates the genetic differences between animals in net profitability per cow joined for an example commercial Wagyu herd in a temperate environment targeting fullblood steer production. Steers enter the feedlot at 425 kg and are subsequently feed for 450 days. They are slaughtered at 750 kg live weight (450 kg HSCW) at 30 months of age. A significant premium in placed on marbling performance. This is a self-replacing herd therefore daughters are retained for breeding.

BREED AVERAGE:

For benchmarking, the average Wagyu BREEDPLAN EBVs for the 2012 drop calves are tabled below.

Wagyu Average EBVs

For further information on BREEDPLAN click here.

DISCLAIMER

The Wagyu GROUP BREEDPLAN Estimated Breeding Values contained in AWA Sale Catalogues were compiled by the Agricultural Business Research Institute (ABRI) from data supplied by the breeders. Neither the Australian Wagyu Association nor the ABRI oversee or audit the collection of this data.