Cattle make the grade in Clemson Bull Test

Published: February 6, 2013

Buyers peruse bulls for auction before the Clemson Bull Test & Heifer Sale. image by: Clemson University

CLEMSON — Commencement came early for a special class at Clemson University: The annual Clemson Bull Test & Heifer Sale Saturday graduated more than six dozen animals to take their place in the cattle industry.

The sale at the T. Ed Garrison Livestock Arena at Clemson was the culmination of a 145-day test in which the animals were constantly monitored for feed intake and growth.

The Clemson Extension Service holds the test to help cattle producers identify superior genetics in bulls that will help improve the next generation of beef cattle — and profits — in South Carolina’s beef business.

"The test is designed to identify genetic traits that will help beef producers make better profits by reducing feed costs," said Matthew Burns, a Clemson Extension animal scientist and coordinator of the bull test. "Bulls that gain weight efficiently in the test are more likely to pass that trait on to their offspring."

Bulls, which were consigned by cattle producers from across the Carolinas, typically gain roughly 500 pounds in the test. Some average up to five pounds per day.

Cattle buyers from three states received transcripts for each "student" in the test: A complete record of performance measures each animal's feed intake and weight gain. It also reports how efficiently the bulls turn feed into meat, a process scientists call "residual feed intake," or RFI.

"The RFI is especially important because it tells the cattle producer a lot more than just growth rate alone. It looks at efficiency in feed conversion, which is especially important as  feed prices rise," Burns said. "We're trying to give cattle producers every possible competitive advantage."

In the length of time an animal spends in a feedlot, a small difference in efficiency could mean well over $100, perhaps the difference between a cattle producer making a profit or losing money.

"The cost of feed accounts for the single greatest cost in beef production. Even small improvement in feed efficiency can produce big savings," Burns said.

The bulls began the test in September at the Clemson Beef Cattle Farm on the Simpson Experiment Station near Pendleton. More than $150,000 worth of bulls and heifers were auctioned in the sale.

Clemson has held the bull test sale annually for more than three decades. Recent advances in technology have enabled the scientists to measure feed intake individually for each bull, even though the animals feed in the same pen.

"When a bull puts his head through the bars and begins to eat, the node records his tag number, weight of the bunk, date and time for every second he is eating at the bunk," Burns said.

The data is transmitted to a computer for analysis. The system allows the scientists performing the test to get immediate information on individual bulls and comparative data with the others.

"When a bull is taking less feed than the pen average or has decreased 25 percent or more from his previous day’s intake, his number shows up,” Burns said. “This information is used on a daily basis to help identify bulls that may have health concerns."

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