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Prime Traits & Desirable DNA

The Australian Wagyu Association helps us get the best genetic traits out of every animal through their simplified reporting system. Estimated Breeding Values (EBVs) indicate the strength and ultimate success of the animal's genetic makeup; leading to production maximization.

  • Gestation Length EBV (GL) (days)
    Based on AI records. Lower (negative) GL EBVs indicate shorter gestation lengths which generally relate to lighter birth weights and easier calving.
  • Birth Weight EBV (BW) (kg)
    Based on the measured birth weight of animals, 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 Milk EBV (MILK) (kg)
    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.
  • 200-Day Growth EBV (200) (kg)
    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-Day Weight EBV (400) (kg)
    Calculated from the weight of animals 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-Day Weight EBV (600) (kg)
    Calculated from the weight of animals 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 EBV (MCW) (kg)
    Based on the weight of the cow when the calf is weighed for weaning, adjusted to five years of age. This EBV is an estimate of the genetic difference in cow weight at five years of age and is an indicator of growth at later ages and potential feed maintenance requirements of the females in the breeding herd. Breeders of steers wishing to grow animals out to a larger weight may also use the Mature Cow Weight EBV.
  • Scrotal Size EBV (SS) (cm)
    An indicator of male fertility (semen quality and quantity) in Western breeds of cattle. Higher (positive) EBVs indicate higher fertility. There is also a small negative correlation (desirable) with the age of puberty and fertility in female progeny. The relationship between scrotal size and fertility in Wagyu is assumed, but not proven
  • Carcass Weight (CWt) (kg)
    Based on abattoir carcass records and live weight measurements (particularly 600 Day weight) and is an indicator of the genetic differences in carcass weight at the industry average slaughter age of 990 days. Larger positive values are more favourable.
  • Eye Muscle Area EBV (EMA) (cm squared)
    Estimates genetic differences in eye muscle area at the 12/13th rib site of a 420kg dressed carcass. A higher positive EBV indicates larger eye muscle area and therefore higher retail beef yields. Ultrasound, AUSMeat and Japanese Digital Image Camera measured Eye Muscle Areas from slaughter animals contribute to this EBV.
  • Rump Fat EBV (RUMP) (mm)
    Estimates the genetic differences in fat depth at the P8 site of a 420kg dressed carcass. A higher positive EBV indicates more subcutaneous fat and earlier maturity.
  • Retail Beef Yield Percent EBV (RBY) (%)
    Estimates the genetic differences in total (boned out) meat yield as a percentage of a 420kg dressed carcass. A higher positive EBV indicates higher percentage yield for the 420kg carcass weight.
  • Marble Score EBV (MS) (AUSMeat Marble Score)
    An estimate of the genetic difference in the AUSMeat Marble Score in a 420kg carcass. Marble Score EBV utilizes AUSMeat Marble score on a scale of 1 to 10 where 10 is equivalent to an AUSMeat Marble Score grading of 9+. Where results from the Meat Image Japan digital carcass camera are available, Camera Marbling Percentage and Marble Fineness are also used to calculate Marble Score EBV as the genetic correlations between these measures and AUSMeat Marble Score are very high. Larger positive values are more favorable.
  • Marble Fineness EBV (MF) (Marbling Fineness Index)
    Estimates the genetic differences in the Marbling Fineness Index (degree of fineness of marbling fat) as measured by the Japanese Digital Image Camera. A higher more positive EBV indicates higher levels of marbling fineness.
  • Wagyu Breeder Index (WBI)
    The Wagyu Breeder Index estimates the genetic differences between animals in net profitability per cow joined in a commercial fullblood or purebred self-replacing herd that has a low-input, grass-based production system. Heifers are retained for breeding and steers and surplus females are sold as feeders for feedlot finishing. Steers are assumed to be slaughtered at 32 months after 550 days of feedlot finishing targeting 460kg carcases. Heifers are retained for breeding and therefore maternal traits are of importance. Marbling is targeted at breed average with optimised growth. In terms of relative economic importance, the WBI places the following emphasis on these main traits: 37% on marble score (MS); 12% on sale liveweight; 9% on meat yield; 7% on dressing percentage and 13% placed on other cow and calf traits.
  • Self-Replacing Breeding Index (SRI)
    The Self-replacing Index can be used to select fullblood bulls that will produce more profitable females when these are retained in fullblood or purebred herds, in addition to profitable slaughter progeny. The SRI estimates the genetic differences between animals in terms of net profitability per cow joined for production of replacement females and slaughter steers to a carcass weight of 435kg at 32 months of age and a 385kg carcass from surplus heifers at 29 months of age. In terms of relative economic importance, the SRI places the following emphasis on these main traits: 41% on marble score (MS); 14% on Residual Feed Intake (RFI) feedlot; 12% on sale liveweight (which will reflect the growth potential and therefore carcass weight of an animal); 9% on meat yield; 6% on dressing percentage and 23.5% placed on other cow and calf traits.
  • Fullblood Terminal Index (FTI)
    The Fullblood Terminal Index has an increased weighting on the Marble Score EBV and can be used to select bulls to produce profitable slaughter progeny where none are retained for breeding. The FTI estimates the genetic differences between animals in terms of net profitability per cow joined based on production of slaughter stock only, with a 435kg carcass from steers at 32 months of age and a 385kg carcass from heifers at 29 months of age. In terms of relative economic importance, the FTI places the following emphasis on these main traits: 64% on MS; 11% on Residual Feed Intake (RFI) feedlot; 9% on sale liveweight; 7% on meat yield; 5% on dressing percentage and 3% placed on other young animal traits and 0% on maternal traits.
  • F1 Terminal Index (F1I)
    The F1 Terminal Index has an increased weighting on the Marble Score EBV and can be used to select bulls to produce profitable F1 slaughter progeny where none are retained for breeding. The F1 Index estimates the genetic differences between animals in terms of net profitability cow joined based on production of a 420kg carcase from steers and a 387kg carcase from heifers at 28 months of age. In terms of relative economic importance, the F1 Index places the following emphasis on these main traits: 68% on MS; 9% on Residual Feed Intake (RFI) feedlot; 4% on sale liveweight; 6% on meat yield; 4% on dressing percentage and 9% placed on other young animal traits and 0% on maternal traits.
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