By Sharon Omahen
University of Georgia
Ultrasound isn't limited to helping parents decide whether to buy pink or blue baby clothes. Now it's helping cattlemen provide better steaks. It's giving them a virtual look at beef cuts long before their animals head for the stockyard.
"The success of beef producers depends on their ability to provide high-quality, consistent end products to consumers," said Dean Pringle, a University of Georgia animal scientist who works closely with the state's cattle producers.
Newest tool available
Many management practices help farmers improve beef quality. But ultrasound is one of their most effective technologies. It's been around since the 1950s, Pringle said, but only in the past five to 10 years has the beef cattle industry fully embraced it.
"Real-time ultrasound can be used to measure various carcass traits in live animals," he said. "You can measure an animal's intramuscular fat percentage in the ribeye and, from that, predict its marbling score and (U.S. Department of Agriculture) quality grade. Intramuscular fat in the rump is also being researched at UGA to possibly improve this prediction."
Ultrasound can give farmers estimates of the ribeye area, back fat, rump fat and the percentage of intramuscular fat in the ribeye. Using its high-frequency sound waves to "see" under the animal's hide is harmless to the animal, he said.
From a sound-emitting probe placed snugly on the animal's back, sound waves penetrate its tissues. They then reflect off the boundaries between hide, fat and muscle layers.
Sound waves do the trick
"As the sound waves reflect back, a cross-sectional image is created (and) displayed on a computer monitor," Pringle said.
"Ribeye area and back fat are measured between the animal's 12th and 13th ribs," he said. "These traits, along with rump fat, are highly related to the retail product yield."
As the fat measurements increase, they have a negative effect on the yield of beef cuts. An increase in the ribeye area, though, creates a positive effect, he said.
By enabling farmers to predict meat quality, ultrasound is helping them select their best breeding stock.
Before ultrasound, cattlemen evaluated a sire's carcass merit by studying the carcass quality of the animal's offspring.
"This process was slow, labor-intensive and expensive," Pringle said. "The average time taken to prove a sire produced high-quality carcasses was five to eight years and cost producers $5,000 to $10,000. Now that can be done at a year of age."
Culling out the bad producers
Ultrasound can give farmers enough data on their bulls and heifers to decide rightly when to cull cattle from their herds.
"Culling decisions need to be based on a combination of reproduction, growth and end-product," he said. "Ultrasound offers a means to accurately measure the latter."
Ultrasound carcass traits are considered highly inheritable, he said. "So now selection of bulls and replacement heifers can be based on these traits," he said, "and producers can bring about genetic change in their calves."
To get accurate measurements, ultrasound images must be taken by a certified technician, Pringle said. They cost $12 to $16 per head. Those images are sent to a centralized computer lab for interpretation.
Pringle has trained animal ultrasound technicians as part of his faculty responsibilities in the UGA College of Agricultural and Environmental Sciences. In September, the UGA animal and dairy science department will host the national beef cattle ultrasound certification program in Athens, Ga.
"If you aren't going to use a certified technician, it's a moot point," Pringle said. "And if purebred producers aren't using ultrasound, I suggest they start. If not, they'll be behind the curve."
(Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.)