Making sure cattle use their feed efficiently is key to affordable beef and sustainable businesses, says University of Idaho animal scientist Rod Hill, whose book on that topic was published in September.
Hill, a livestock physiologist in the College of Agricultural and Life Sciences, has spent much of his career conducting feed efficiency studies on cattle. His studies range from monitoring the animal as it gains weight all the way to the molecular realm to understand how cattle grow and why there is so much animal-to-animal variation in feed efficiency.
“There are obviously a multitude of factors involved,” Hill said, ranging from the individual animal’s metabolism, genetics, feed quality and others.
“The really important point, I think, is there is a lot of natural biological variation in cattle and that’s one of the things we would like to understand.”
He enlisted 33 experts at the University of Idaho and worldwide to cover the spectrum on the science of feed efficiency. The book, “Feed Efficiency in the Beef Industry,” also tries to offer valuable information to audiences ranging from cattle producers to animal scientists, Hill said.
“We designed the book so the opening chapters are very producer friendly, and then progress through the more difficult chapters. The chapters at the beginning are also very important information for students to understand the industry context. So it could be a textbook or it could be used by producers and allied industry people,” Hill said.
The later chapters get into some detailed discussions of research and will probably be most useful to graduate students or scientists.
“There were so many different factors and interactions that I just saw the need to put a book together that explored the complexities of all the different important production and quality traits that we need to think about when we think about efficiency,” Hill said.
“The really important point, I think, is there is a lot of natural biological variation in cattle and that’s one of the things we would like to understand,” he added.
For example, if there are two steers that are a similar weight and growing at a similar rate, the amount of feed they consume can be vastly different, Hill said. One can be eating 35 percent more feed than its sibling.
Placed side by side in a pen, a rancher or an expert couldn’t tell the two apart, he added. “Being able to actually measure individual animal intake on large numbers of animals is one of the greatest technology advances that we’ve utilized,” Hill said.
With funding from the National Science Foundation, the University of Idaho College of Agricultural and Life Sciences bought a GrowSafe system five years ago that allows monitoring individual animal’s eating habits.
Hill works with the system that is located at the Nancy M. Cummings Research, Extension and Education Center near Salmon, a 1,000-acre, working-scale cattle ranch with some 320 pairs that rely mostly on pasture.
John B. Hall, Cummings Center superintendent and one of the contributors to Hill’s book, recently invited cattle producers to contract the use of the feed monitoring system.
The facility caters to the cattle industry’s seed stock producers, those who supply young cows and bulls to larger operations to bring specific genetic traits to their herds, said Hall, who is based at the Cummings Center near Salmon.
The producers are particularly tuned in to feed efficiency traits, he added.
“We have to be aware of many factors that contribute to profitability and sustainability of beef operations,” Hill said. “For example, we have to simultaneously maintain and improve multiple traits like product quality, weight gain and fertility along with feed efficiency. It’s important to keep the big picture in mind.”
Individual factors contribute many different pieces to the overall feed-efficiency equation, he said, noting that 30 to 40 percent of an individual animal’s feed efficiency is based on its metabolism. Another 10 percent is based on behavior, whether the animal eats large or small meals. The feed itself and its digestibility accounts for about 10 percent of the variation in feed efficiency.
An animal’s body composition registers about 5 percent. So an animal that is fatter, but otherwise similar to its neighbor, is likely to be less efficient because it actually takes more energy, and so more feed, to lay down fat than it does muscle, Hill said.
Other University of Idaho researchers who contributed to the book included J.D. Wulfhorst and Stephanie Kane.