Understanding Breedplan - What does it all mean?
Tyson Angus
The Graph Above The Bull
At all official Society sales and at some shows, the bull’s EBVs for each trait are displayed on a graph. The vertical mid point on the graph is the breed average for each recorded trait. Coloured bars that appear on the right of the mid point are advantageous whilst those on the left have to be treated with caution. Tyson is an easy calving bull as shown by the yellow Calving Ease Dir. bar to the right of breed average which shows he is in the top 5% of the breed for this trait. He will however throw heavier calves as shown by the yellow Birth Weight bar to the left of the mid point breed average.
Breeders should select a bull according to the traits that are most important to their breeding programme. For example if you want replacement heifers then Calving Ease Dtrs and Milk are important whereas if you are producing suckled calves then Calving Ease Direct, Birth Weight and 400 Day Weight will be important and so on.
Click to view Percentile Bands for Born Calves
Estimated Breeding Values (EBVS)
The EBV is the best estimate of an animal's genetic merit for that trait.
^ Back to chartAccuracy
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.
Low accuracies should be treated with caution.
^ Back to chartCalving Ease
Calving Ease EBVs are based on calving difficulty scores, birth weights and gestation length information. What type of cows do you have? Larger framed cows may stand a bull with a more negative EBV for Calving Ease Direct. Smaller cows or heifers require bulls with average or positive EBVs for Calving Ease.
Negative EBVs mean more difficult calving whilst positive EBVs mean easier calving.
DIR: Calving Ease Direct indicates how this animal influences the birth of its progeny.
High negatives mean more difficult calving whilst high positives are easy calving.
DTRS: Daughter’s calving ease indicates how well the animal produces daughters that have easier calving. This is an important trait if you are breeding your own replacements.
Again, high negatives are more difficult whilst high positives are easier.
^ Back to chartBirth
GL: Gestation Length EBV (days) is based on AI records. Lower (negative) GL EBVs indicate shorter gestation lengths which generally relate to easier calving and increased growth after 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 the less is the likelihood of a difficult birth. This is particularly important when selecting sires for use on heifers.
^ Back to chartFertility
SS: Scrotal Size EBV (cm) is an indicator of male fertility in regards to semen quality and quantity. There is also a small negative correlation with age of puberty in female progeny i.e. the daughters of bulls with larger testicles may come into season at an earlier age.
Higher (positive) EBVs indicate higher fertility.
^ Back to chartGrowth
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.
Bulls with high 200 day milk EBVs have more milky daughters.
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.
The higher the 200 day EBV then the higher the suckled calf or weaning weight.
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.
Higher 400day EBVs indicate earlier maturing progeny with a greater weight at an earlier age.
600: 600-Day Weight EBV (kg) is calculated from the weight of progeny adjusted to 600 days and for damage. 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 give cows with lower maintenance costs.
^ Back to chartCarcase
CWT: Carcase Weight EBV (kg) estimates the genetic difference in carcase weight at a standard age of 650 days.
An important trait for finished cattle production.
EMA: Eye Muscle Area EBV (cm2) estimates genetic differences in eye muscle area of a 300kg dressed carcase.
More positive EBVs for Eye Muscle Area indicate better muscling on animals.
RIB: Rib Fat EBV (mm) estimates the differences in fat depth at the rib in a 300kg dressed carcase.
More positive EBVs indicate more subcutaneous fat and earlier maturity but may incur penalties at grading.
RBY%: Retail Beef Yield Percent 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. This is an important trait in finished steers and heifers.
^ Back to chartTerminal Sire Index
The Terminal Sire Index is a combination of growth and carcase trait EBVs into a single figure and is a measure of a bull’s ability to produce prime steers and heifers for the finished market. When using an Aberdeen-angus bull on cross bred cows you should consider placing extra emphasis on the Calving Ease Direct EBVs (more positive) of the sire to allow for possible heavier birth weights of his calves due to hybrid vigour.
The higher the Terminal Index then the progeny mature at an earlier age and at a heavier weight.
^ Back to chartSelf Replacing Index
The Self Replacing Index is used when selecting replacement females from within the herd while finishing steers and surplus heifers at 18 - 20 months of age. There is emphasis on Calving Ease Daughters (Dtrs) and maternal traits but also including some growth trait EBVs. Again when using an Aberdeen-angus bull on cross bred cows you should consider placing extra emphasis on the Calving Ease Direct EBVs (more positive) of the sire to allow for possible heavier birth weights of his calves due to hybrid vigour.
The higher the Self Replacing Index then the female progeny will make better herd replacements.
^ Back to chartPercentile Bands for 2006 Born Calves
| Percentile Band |
Calv. Ease Direct (%) |
Calv. Ease Dtrs (%) |
Gest. Len. (days) |
Birth Wt. (kg) |
200 Day Wt. (kg) |
400 Day Wt. (kg) |
600 Day Wt. (kg) |
Mat. Cow Wt. (kg) |
Milk (kg) |
Scrotal Size (cm) |
Car- case Wt. (kg) |
Eye Muscle Area (sq.cm) |
Rib Fat (mm) |
Retail Beef Yield (%) |
IMF % |
Angus Term- inal Index (GBP) |
Angus Self Repl- acing Index (GBP) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Top Value | +9.7 | +10.7 | -2.8 | -3.4 | +58 | +102 | +119 | +116 | +20 | +3.4 | +84 | +5.5 | -2.8 | +3.2 | +1.4 | +44 | +60 |
| Top 1% | +6.2 | +7.6 | -1.2 | -1.0 | +43 | +76 | +91 | +90 | +16 | +1.8 | +59 | +3.5 | -1.8 | +2.1 | +0.7 | +34 | +45 |
| Top 5% | +3.9 | +4.2 | -0.5 | +0.1 | +38 | +66 | +80 | +78 | +13 | +1.3 | +51 | +2.9 | -1.3 | +1.6 | +0.4 | +29 | +38 |
| Top 10% | +2.6 | +3.0 | -0.1 | +0.7 | +35 | +61 | +74 | +73 | +12 | +1.0 | +46 | +2.7 | -1.0 | +1.2 | +0.3 | +26 | +34 |
| Top 15% | +1.7 | +2.3 | +0.2 | +1.0 | +33 | +57 | +71 | +69 | +11 | +0.9 | +44 | +2.5 | -0.8 | +1.1 | +0.3 | +24 | +32 |
| Top 20% | +1.1 | +1.9 | +0.4 | +1.3 | +31 | +55 | +68 | +67 | +10 | +0.8 | +41 | +2.4 | -0.7 | +0.9 | +0.2 | +23 | +30 |
| Top 25% | +0.5 | +1.5 | +0.6 | +1.5 | +30 | +52 | +65 | +64 | +9 | +0.7 | +40 | +2.3 | -0.6 | +0.8 | +0.2 | +22 | +28 |
| Top 30% | 0.0 | +1.2 | +0.7 | +1.7 | +29 | +50 | +63 | +62 | +8 | +0.6 | +38 | +2.2 | -0.5 | +0.7 | +0.2 | +21 | +27 |
| Top 35% | -0.5 | +0.8 | +0.8 | +1.9 | +28 | +49 | +61 | +60 | +8 | +0.6 | +36 | +2.1 | -0.4 | +0.7 | +0.1 | +21 | +26 |
| Top 40% | -0.9 | +0.5 | +1.0 | +2.0 | +27 | +47 | +59 | +58 | +7 | +0.5 | +35 | +2.1 | -0.3 | +0.6 | +0.1 | +20 | +25 |
| Top 45% | -1.4 | +0.3 | +1.1 | +2.2 | +26 | +45 | +57 | +56 | +6 | +0.5 | +34 | +2.0 | -0.3 | +0.5 | +0.1 | +19 | +24 |
| Top 50% | -1.9 | 0.0 | +1.2 | +2.3 | +25 | +44 | +55 | +54 | +6 | +0.4 | +32 | +1.9 | -0.2 | +0.5 | +0.1 | +18 | +23 |
| Top 55% | -2.4 | -0.3 | +1.3 | +2.5 | +24 | +42 | +53 | +53 | +5 | +0.4 | +31 | +1.9 | -0.1 | +0.4 | 0.0 | +18 | +22 |
| Top 60% | -2.9 | -0.6 | +1.4 | +2.7 | +24 | +40 | +51 | +51 | +4 | +0.3 | +30 | +1.8 | -0.1 | +0.3 | 0.0 | +17 | +21 |
| Top 65% | -3.5 | 0.9 | +1.6 | +2.8 | +23 | +39 | +50 | +49 | +4 | +0.3 | +28 | +1.7 | 0.0 | +0.3 | 0.0 | +16 | +20 |
| Top 70% | -4.0 | -1.3 | +1.7 | +3.0 | +22 | +37 | +48 | +47 | +3 | +0.3 | +27 | +1.7 | 0.0 | +0.2 | 0.0 | +15 | +20 |
| Top 75% | -4.8 | -1.7 | +1.8 | +3.2 | +20 | +35 | +46 | +45 | +2 | +0.2 | +25 | +1.6 | +0.1 | +0.1 | -0.1 | +15 | +19 |
| Top 80% | -5.5 | -2.2 | +2.0 | +3.4 | +19 | +33 | +43 | +42 | +2 | +0.2 | +24 | +1.5 | +0.2 | +0.1 | -0.1 | +14 | +18 |
| Top 85% | -6.4 | -2.8 | +2.2 | +3.7 | +18 | +31 | +40 | +40 | +1 | +0.1 | +22 | +1.4 | +0.3 | 0.0 | -0.1 | +13 | +17 |
| Top 90% | -7.7 | -3.6 | +2.4 | +4.0 | +16 | +28 | +37 | +36 | -1 | 0.0 | +20 | +1.3 | +0.4 | -0.1 | -0.2 | +12 | +15 |
| Top 95% | -9.8 | -4.8 | +2.8 | +4.6 | +14 | +24 | +31 | +30 | -2 | -0.1 | +17 | +1.0 | +0.5 | -0.3 | -0.3 | +10 | +13 |
| Top 99% | -14.4 | -7.6 | +3.5 | +5.9 | +10 | +16 | +23 | +21 | -5 | -0.4 | +12 | +0.5 | +1.1 | -0.8 | -0.5 | +7 | +9 |
| Low Value | -22.4 | -13.7 | +5.2 | +11.6 | -3 | -9 | -11 | -12 | -12 | -2.5 | -7 | -0.9 | +3.2 | -2.6 | -1.2 | -2 | -7 |