Ultrasound Guidelines

Ultrasound data is a tool used to enhance the accuracies of carcass EPDs.

Yearling Bulls

How to Manage: Bulls should be placed on a high-energy ration after weaning. This will be important for discriminating among bulls for fat thickness and marbling traits.

When to Measure: The best time to collect ultrasound images on bulls is at or near the end of their gain test.

Age of Bulls: Bulls should be between 320 and 440 days of age: same as yearling measures.

Traits to Measure: Rump Fat Thickness, Rib Fat (Fat Thickness), Rib Eye Area (REA), and Percentage Intramuscular Fat (%IMF).

Yearling Replacement Heifers

How to Manage: Normal heifer development program. Preferably using a moderate to high-energy ration, which allows heifers to express their genetic potential for fat thickness and percentage intramuscular fat.

When to Measure: Heifers may or may not express their full potential for fat and marbling traits at the same time as bulls. Therefore, the recommended time to scan heifers is prior to breeding.

Age of Heifers: Between 320 and 460 days or just prior to breeding.

Traits to Measure: Rump Fat Thickness, Rib Fat (Fat Thickness), Rib Eye Area (REA), and Percentage Intramuscular Fat (%IMF).

Management and Contemporary Groups

A management group is a set of cattle that are exposed to the same environmental conditions and includes ALL cattle within that environment. Therefore, ultrasound contemporary groups are formed from the latest information recorded (weaning or yearling), and:

  1. Three day scan period – animals that are scanned more than three days apart will be grouped separately.
  2. Appropriate age – bulls younger than 320 days and older than 440 days and heifers younger than 320 days and older than 460 days will be considered irregular and placed in their own contemporary group.
  3. Group code – if animals are indicated as managed/fed differently, they will be contemporaried separately.

Requesting Ultrasound Data Service

  1. Barnsheets with yearling animals are available via the web site under REDS or from the office upon request. Animals not listed should be requested from the office by registration number. A barnsheet containing only the additional animals will then be faxed, mailed, or e-mailed to the breeder. Barnsheets are to be given to the technician on day of scanning.
  2. Schedule an appointment with an Ultrasound Guideline Council (UGC) certified technician about one month in advance. A list of technicians certified by UGC is available on the RAAA website, or can be provided by the RAAA National Office.
  3. Be sure that all animals in a contemporary group are scanned.
  4. Weigh all cattle the same day they are being scanned.
  5. Small herds in close proximity should coordinate their scanning times. Per head costs may be less expensive if technicians are able to scan large numbers of cattle in a small geographical area.
  6. After the herd is scanned, the technician overnights images to an UGC certified lab.
  7. Images are then interpreted by the ultrasound processing lab. Images that are not an adequate measure of a particular trait will be rejected. The table below lists guide lines that ensure optimum scanning conditions that are the responsibility of both the technician and the breeder.
  8. Analyzed data is then sent electronically to the RAAA National Ooffice.
  9. A summary report of ultrasound measurements (including: rump fat, backfat, ribeye area, and percent intramuscular fat) adjusted to 365 days is made available via member data REDS, Ultrasound – Summary. This report will be mailed only upon request by the owner of the animal(s) included within the report. The National Office will e-mail or mail a copy of the ultrasound summary report to other parties only when instructions from the owner/technician to the processing lab indicate to do so.
Problem Breeder Technician
Squeeze Chute X
Electrical Supply X
Clipped Cattle X
Weight Collected X
Age Range X
Supplemental Heat X
Equipment Calibration X
Gain & Focus Setting X
Reference Points X
Poor Contact X
Correct # of Images X