Red Angus Association of America

by Belinda Rowbotham, RAAA Staff

The beef industry of today is faced with many challenges, one of which is improving the consistency of beef. The solution to this problem is for producers to continue to improve carcass merit by identifying the carcass genetics of their seedstock. In the past, this was only achieved through progeny testing. Progeny testing requires a sire to have approximately twenty harvested calves to be compared with a reference sire's harvested progeny within the same contemporary group. For most producers this is impractical. Now, with advancements in technology, real time ultrasound offers producers the means to gather data that can enhance carcass genetic predictions without harvest.Nearly two years ago, the Red Angus Association of America conducted a pilot study to determine if real time ultrasound would improve the accuracies of carcass EPDs. This study as well as many others has shown that the relationship between ultrasound measurements of yearling seedstock and EPDs based on carcass data are strongly related. Now that the results of this study show that ultrasound can allow producers to gather useful data for the calculation of carcass EPDs, the RAAA National Office has made it a part of the Total Herd Reporting calendar. In order to encourage breeders to participate, barnsheets are mailed with the Spring and Fall Herd Inventories. These barnsheets contain information on the animals to be scanned and should be given to the technician at the time of scanning. As decided by the Breed Improvement Committee and the RAAA Board of Directors in 1999, all ultrasound data that will be used for EPDs must be processed through the National Centralized Ultrasound Processing Lab & Technology Center in Ames, Iowa. At the CUP lab, the data is interpreted by one technician and then cross-checked by another technician, which ensures that the RAAA will receive only unbiased accurate data. Furthermore, image interpreters maintain a high level of accuracy through periodic proficiency testing.

Although the ultrasound program is strictly voluntary, the RAAA would like for breeders to participate. As with anything that goes towards the calculation of EPDs, there must be guidelines that are followed. RAAA developed a protocol for ultrasound that follows guidelines set by the Beef Improvement Federation. They are as follows:

GUIDELINES

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.

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

Management and Contemporary Groups

Contemporary groups are formed form 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 mailed with THR Spring/Fall Inventories. Animals not listed on the barnsheets should be requested from the RAAA National Office by registration number. A barnsheet containing only the additional animals will then be faxed or mailed to the breeder. Barnsheets are to be given to the technician on day of scanning.

2. Schedule an appointment with the CUP technician about one month in advance. A list of technicians certified by CUP is available from the RAAA National Office. An updated technician list will be available in the January ARA issue after the Annual Proficiency Testing and Certification session.

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 the CUP lab.

7. Images are then interpreted by the CUP lab. Images that are not an adequate measure of a particular trait will be rejected. Table 1 lists guidelines 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 Office.

9. A summary report with measurements for Rump, Rib Fat, REA, and %IMF adjusted to 365 days is then sent to the breeder.

Ultrasound is a good method for seedstock producers to achieve a fast and objective prediction on the composition of their cattle, improving the accuracies of their carcass EPDs. Dr. Doyle Wilson from Iowa State sums it up well by saying, "In the hands of properly trained technicians, ultrasound offers the beef seedstock industry with one of the most powerful tools for genetic improvement of carcass merit ever devised. Its time is now, not let's wait and see."