The rising cost of feeding cattle is causing producers to look for ways to improve the efficiency of the animals consuming expensive feed.

“The major cost in producing cattle is feed,” says John Dhuyvetter, area livestock specialist at North Dakota State University’s North Central Research Extension Center in Minot. “The high demand and price for corn and other commodities is raising finishing costs and devaluing feeder cattle. It’s also impacting land use decisions, which puts inflationary pressure on pasture and forage costs.”

Feed storage, processing, additives and delivery that minimize waste and maximize utilization are critical to improving efficiency, according to Dhuyvetter. He believes large economic impacts also might be possible through genetic improvements that make cattle more metabolically efficient in their use of feed. Research has identified heritable differences in cattle for feed efficiency.

“The amount of variation and potential savings are large, stimulating study and technology regarding how to measure and improve,” he says.

Feed yards routinely have tracked pen feed conversion (pounds of feed consumed per pound of gain) as a key economic benchmark. However, feed intake never has been pushed widely as a genetic trait for several reasons. One is that measuring actual feed consumption for individual animals is difficult. Two, good conversions are favored by high feed intake in which maintenance energy needs are diluted over high average daily gains. Better feedlot conversion ratios are associated with higher growth rate and larger-sized cattle.

Feed intake soon may be a bigger factor in animal genetics, though. Some advancing technologies for measuring individual animal feed intake and expressing feed efficiency are moving the industry toward being able to select cattle that eat less while gaining the same, Dhuyvetter says.

This technology includes feed bunks with load-cell scales that continually weigh a feed tub accessed by one animal at a time. The tub has a reader to identify the animal by radio frequency ear tag and computerize the data accumulation to track what an individual animal eats while in the pen on the feeding trial.

Using the feed intake information to calculate a residual feed intake (RFI) identifies metabolic efficiency differences among animals independently of average daily gain and body size. RFI is defined as the difference between what an animal actually consumed and what was expected based on its growth and maintenance.

Testing groups of yearling bulls identifies animals with a negative RFI, which means they consumed less than expected for performance achieved, as well as positive RFI bulls, which consumed more feed than expected.

“This information can be utilized in the selection of bulls expected to sire calves with lower finishing feed costs and daughters with lower feed maintenance requirements,” Dhuyvetter says.

In yearling bulls on feed tests, the variation is more than 5 pounds less feed per day for similar performance. Selection for low RFI could reduce cow herd maintenance requirements by up to 10 percent through time. Research also indicates selection for low RFI would lower methane emissions and reduce nutrients in manure.

A number of bull testing and marketing centers, including a couple of the largest test centers in the U.S. and Canada, have invested in the equipment to be able to measure RFI and evaluate bulls for feed efficiency. Additionally, several large seedstock breeders are measuring RFI on some of their best breeding prospects, and more and more land-grant universities are becoming set up to measure individual efficiency in larger groups of animals, which will contribute to more meaningful research.

A third factor - the discovery of several genetic markers related to an animal’s ability to convert feed – could have an impact on improving efficiency.

Because of the cost and complexity of measuring actual feed intake and calculating RFI, DNA profiling would be a much simpler means to evaluate a larger number of animals for their genetic ability to use feed more efficiently, Dhuyvetter says.

Current markers identify a portion of the variation in RFI, with the most favorably rated genotypes saving about 2.5 pounds of feed per day at similar gains, compared with the least favorable genotypes. For many breed populations, the practical range of variation that current markers identify is more likely to be .5 to 1 pound.

“The economic potential from widespread improvement in feed efficiency is huge for the cattle industry,” Dhuyvetter says. “At today’s high grain and feed prices, the measurement, evaluation and application of improving feed efficiency are rightly receiving a lot of industry and academic attention.”

NDSU Agriculture Communication