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4. Carcase Breeding Values


Carcase breeding values provide information on hard to measure traits which can significantly affect the value of a beef animal.  Carcase breeding values provide insight into the type of carcase an animal will yield.  Performance recording for structural traits must be recorded by an accredited technician.

 

Click on the individual trait you are interested in:

 

 Carcase Weight (CTW)  Eye Muscle Area  Rib Fat
Retail Beef Yield   Rump Fat  IMF

 

 


Finding an accredited technician   

Ultrasound scanning measurements for Angus BREEDPLAN must be collected by an accredited technician. Ultrasound scanning measurements not collected by an accredited technician will not be included in Angus BREEDPLAN.

 Click here for a list of accredited technicians

 


Carcase Weight (CTW)

Carcase EBVs are estimates of genetic differences between animals in hot standard carcase weight at 750 days of age.

Higher Carcase Weight EBVs indicate the animal is expected to produce progeny with heavier carcase weights.

Carcase Weight EBVs are expressed in kilogram units.


Eye Muscle Area (EMA)

Eye Muscle Area (EMA) EBVs are estimates of genetic differences between animals in eye muscle area at the 12/13th rib site in a 400 kg carcase.  Higher EMA EBVs indicate the animal is expected to produce progeny with larger eye muscle area, relative to carcase weight.

EMA EBVs are expressed in square centimetre units.


Rib Fat (RIB)

Rib Fat EBVs are estimates of genetic differences between animals in fat depth at the 12/13th rib site in a 400 kg carcase.   Higher Rib Fat EBVs indicate the animal is expected to produce progeny with greater fat depth in a 400 kg carcase.

Rib Fat EBVs are expressed in millimetre units.


Rump Fat (P8)

Rump Fat EBVs are estimates of genetic differences between animals in fat depth at the P8 rump site in a 400 kg carcase.  Higher Rump Fat EBVs indicate the animal is expected to produce progeny with greater fat depth in a 400 kg carcase.

Rump Fat EBVs are expressed in millimetre units.


Retail Beef Yield

Retail Beef Yield (RBY) EBVs are estimates of genetic differences between animals in boned out saleable meat from a 400 kg carcase.   Higher RBY EBVs indicate the animal is expected to produce progeny that yield a higher percentage of saleable beef from a 400 kg carcase.

RBY EBVs are expressed in percentage units.


Intermuscular Fat (IMF)

Intramuscular Fat (IMF) EBVs are estimates of genetic differences between animals in intramuscular fat (marbling) at the 12/13th rib site in a 400 kg carcase.  Higher IMF EBVs indicate the animal is expected to produce progeny with a higher percentage of intramuscular fat (marbling) in a 400 kg carcase.  IMF EBVs are expressed in percentage units.


Collecting Live Animal Ultrasound Scanning Information 

Live animal ultrasound scanning measurements, in association with abattoir carcase data, are used to calculate Carcase EBVs within Angus BREEDPLAN.  Angus BREEDPLAN can analyse live animal ultrasound scanning measurements from animals that are between 300 – 800 days of age at scanning, with the majority of animals being scanned as either yearlings or rising 2 year olds (i.e. around 600 days of age).

It is critical that animals are in appropriate condition when live animal ultrasound scanning measurements are collected. As a rough guide, animals require a minimum average rump fat depth of 4–5 mm (or a minimum average rib fat measurement of 3 mm).

Results for IMF will be further optimised if the majority of animals have between approximately 2 – 8% IMF when scanned. The effectiveness of the current scanning machines decreases when measuring IMF levels outside this range.

While more than one set of live animal ultrasound scanning measurements can be collected for an individual animal, Angus BREEDPLAN is only analysing the first EMA, rib fat, rump fat and IMF measurement for each animal at this stage.

Consequently, it is only necessary to collect one set of ultrasound scanning measurements on each animal for Angus BREEDPLAN.


Collecting Abattoir Carcase Information 

Abattoir carcase information, along with live animal ultrasound scanning measurements, is used to calculate Carcase EBVs within Angus BREEDPLAN.  While the collection of carcase information from ultrasound scanning provides useful information on live animals, abattoir carcase information is of particular value for genetic evaluation as it represents a direct measure of the attributes of a beef carcase.  Members who are considering embarking on the collection of abattoir carcase information for Angus BREEDPLAN need to be aware that the collection of abattoir information can be challenging, expensive and time consuming.

Specifically, abattoir carcase information will be only be accepted for inclusion in Angus BREEDPLAN if:

  • It has been collected as part of a structured progeny test program
  • Appropriate measurement collection protocol have been followed to ensure the carcase measurements that are collected are of suitable quality for genetic evaluation
  • Animals are between 300 and 1000 days of age at slaughter (i.e. 10 – 33 months).

Abattoir carcase information that does not meet these criteria, such as kill sheets for small groups of steers or cull heifers, or information collected as part of a carcase competition, is not suitable for inclusion in Angus BREEDPLAN.