by Ed Haag | agriculture.com
Extension beef specialist Dan Faulkner admits that when he and his colleagues from the University of Illinois and Iowa State University began collecting data from 225 commercial herds in an effort to better understand what factors had the greatest impact on profitability, few would have predicted that one factor would emerge heads above the rest. “About 56% of the variation in profitability was attributable to feed and hay costs,” he says. “It was a huge factor in determining profitability.”
For Faulkner and others who reviewed the survey results, the data was telling. “To me, if feed costs explain over 50% of the variation in profit, it is the one producers should really focus on,” he says.
One beef scientist who took notice of what the Illinois and Iowa survey revealed was Dan Buskirk, department of animal science, Michigan State University (MSU). For him, there was an obvious follow-up question: What was the specific reason for the variations in profitability in relation to feeding costs?
Buskirk then recalled one of his school’s livestock educators saying that he had observed a marked difference in how effective specific types of round hay feeders were at controlling waste.
After checking the existing literature, Buskirk discovered very little had been published on the subject in recent years. But one study completed in the 1980s showed that losses of hay due to the way it was fed could reach 20% to 30% of the dry matter fed.
New research needed
With several unique designs for large bale feeders in use (with more than one claiming reduced waste potential), Buskirk was curious to see if those claims would stand up under scientific scrutiny. He was particularly interested in how cattle behaved when they were accessing the different feeders. He believed that a better understanding of the relationship between feeder design and animal behavior could provide an opportunity for more efficient feed use and also enhance animal performance and well-being.
Based on his initial findings and the encouragement of his colleagues, Buskirk formed a research team to evaluate four of the most commonly used round bale feeders: the cone feeder, the ring feeder, the trailer feeder, and the cradle feeder. The team would also monitor the feeding behavior for each feeder design and the relationship between feeding behavior, feeder design, and feed loss.
A group of 160 nonlactating, pregnant beef cows from the MSU herd were used to evaluate the quantity of hay loss and feeding behaviors from different round bale feeders.
These animals were split into eight groups of 20 and assigned by weight and body condition score to one of eight pens with the four feeder designs being evaluated. All feeder types provided approximately 37 cm linear feeder space per animal.
Prior to feeding, the round bales were weighed and sampled. During the study, the hay that fell onto the concrete surrounding the feeder was considered waste and was collected and sampled daily. After seven days, each hay feeder type was assigned to a different pen for seven more days.
Because Buskirk felt any discrepancy in waste between feeders would probably be traced back to cattle interaction around the units, he added an animal behavior component to his study. “I knew if we had differences, the next question would be why,” he says. “So at the onset of the project, working with our animal behaviorist, Adroaldo Zanella, we set up video cameras to record the cattle interaction around the feeders.”
No shortage of surprises
For Buskirk and his team, there were surprises once the data was processed. The feeder to receive the highest marks was the cone feeder with a dry matter hay loss of 3.5%, followed by the ring feeder with 6.1%, the trailer feeder with 11.4%, and the cradle feeder with 14.6%.
“My guess before the study was that the cradle feeder would prove the best at reducing waste because any hay that wasn’t consumed over the feeder would drop back down to the bottom of the cradle,” says Buskirk. What he hadn’t calculated when making his prediction was that boss cow behavior would even trump what seemed like a well-designed system.
“We found that with the cradle feeder cows tended to walk alongside of it and butt several cows out of the way at the same time,” he says. “When that happens a cow backs up and drops half of what she is eating on the ground.”
He points out this behavior was observed with both the cradle and the trailer feeder but was nearly absent with the cone and the ring feeders.
Researchers found cattle interaction wasn’t the only reason for excessive waste. Individual cow feeding behavior could result in increased hay loss if it wasn’t controlled by feeder design.
“Round feeders were set lower, which allowed cattle to put their heads directly in the feeder,” says Buskirk. He notes that this offered a more natural grazing position and encouraged the cattle to keep their heads in the feeders throughout much of the process.
“In contrast, with flat-sided feeders, they tended to reach in, grab a mouthful of hay, and pull their heads out to chew it. In the process, some hay ended up on the ground,” he says.
Similarly, feeder designs that required cattle to access hay from under a top rail were far less likely to waste hay since cows didn’t toss it over their backs or along their sides.