Widely adopted in the last decade, clean or "slick" bunk management reduces wasted feed and, in many cases, improves feed efficiency and gain. It may come with a price, though.

"With $150 to $200 premiums for Certified Angus Beef â (CAB) qualifying carcasses, compared to Select, it's a matter of good economic sense to watch the little details," says Larry Corah, vice president of Certified Angus Beef LLC.

Cattle nutritionists explain the finer points of fine-tuning bunk management.

"If you run a clean bunk system, the goal is not to feed the cattle less. It's just to force the cattle to clean up in shorter periods of time," explains Galen Erickson, of the University of Nebraska-Lincoln. There are some benefits to the system, "but the clear disadvantage is the risk of underfeeding," he says. "If you underfeed them, it may have some negative implications on carcass quality."

In two different trials, Erickson found that clean bunk management reduced the percent of cattle grading Choice by four to five percentage points compared to free choice intake. The animal scientist says that could be due, in part, to decreased caloric intake. However, he notes that only one of the trials showed a decrease in dry matter intake.

Robbi Pritchard, of South Dakota State University, says this management approach should actually improve efficiencies and increase the amount of feed consumed.

"The goal should be feed intake that is either unaffected or higher at closeout than when they don't go for slick bunks," he says. "Intake can be higher because you shouldn't have those episodes where cattle back off from the feed."

The challenge is feeding the cattle all they can and will eat.

"You run the risk of limiting energy intake if you slick-bunk manage too aggressively," says Paul Defoor of Cactus Feeders based in Amarillo, Texas.

Bunk readers determine the amount of feed left at a given time and make a call of how much more or less that set of cattle needs for the next 24 hours. The slick bunk system is relatively easy to explain in training employees, he says, but as with anything else must be monitored closely.

"The biggest advantage to the slick bunk approach is that you seldom have to make an estimate of how much feed is left, which takes time and often introduces confusion," says Defoor, who studied the system at New Mexico State University. "The disadvantage is, if you're not careful, you could migrate to where you're really limit feeding."

Defoor��s work at NMSU showed a near 10 percent drop in the number of cattle reaching Premium Choice when fed using aggressive slick-bunk management versus free choice.

Texas Tech University's Mike Galyean collaborated with Defoor on some of that original research. "He did get less of the upper end of Choice and Prime cattle when he applied a fairly restrictive slick-bunk management," Galyean says. "If you restrict throughout the feeding period, the risk is that you will lower quality grade at the end."

Pritchard recalls an SDSU research project that accidentally proved that risk is real. In trying to implement different bunk-management strategies at the same time, the cattle were inadvertently shorted during the first 35 days on feed.

"That just kills percent Choice," he says. "The bunks are always slick and the efficiencies are good, but the percent Choice was awful, and that was from being behind the cattle on the front end."

There are a number of ways feedlot personnel can help combat the negative effects on marbling. The first is to do it right.

"Poor bunk management, where cattle have really cyclic intake patterns, you're going to have cattle out there that experience serious digestive insult," Pritchard says. "Once a steer has been burned, he never regains normal feed intake. Sloppy bunk management should result in a reduction in percent Choice because of those cattle that become 'hard doers.' A good slick-bunk management program probably isn't doing anything to improve marbling, it��s just preventing drops."

Being methodical in your approach makes a difference.

"If you can feed the cattle at the same time and read bunks at the same time every day, that will certainly help," he says.

Galyean adds, "Having a consistent group of people and a consistent way of looking at it is really important."

To avoid any reduction in marbling outcome, he suggests feedyards make gradual changes.

"Slick-bunk programs can vary a lot in aggressiveness," he says. "If somebody is restricting cattle, they don't need to abandon their program. They can be a little less aggressive and it's not a difficult change to make."

The best part is that a slight change won't compromise the program's advantages.

"You're probably not going to give up the efficiency, as long as you're still consistent," he says, "but you might pick up something in terms of quality grade."

That's an area where little things mean a lot. A 2005 CAB survey of major packers showed nearly six percent of all cattle grading Select have marbling scores from 380 to 399, or just 20 Marbling Score points below Choice, Corah says. About the same number are dangerously close to falling out of the Choice mix.

"That says cattlemen need to pay close attention to all areas of production, including bunk management," Corah concludes, "if they want to earn premiums for high quality beef."