Corn silage found beneficial for finishing diets

By Michaela King

When corn prices are high, replacing corn with corn silage and distillers grains in finishing diets is an economical option for cattle feeders. The opportunity to maximize quality and harvest the entire plant are provided when corn silage is fed.

Erin Laborie, a University of Nebraska-Lincoln (UNL) beef systems extension educator, explains in a recent UNL Beefwatch newsletter article that there are some cautions to be considered when using corn silage, but she also notes there are economic benefits to the practice.

Finishing diets that replace corn with corn silage and distillers grains lead to a lower average daily gain. This lower rate of gain contributes to a less favorable feed conversion. It also results in additional days on feed, which leads to higher yardage and interest expenses. However, Laborie notes that if corn prices are high enough, the reduced feed cost associated with corn silage offsets these additional expenses.

If silage shrink is minimized (less than 15 percent), it is economical at 70 percent or less of the price of corn on a dry matter basis.

Comparing diets

UNL conducted a study to further evaluate the effects of feeding elevated levels of silage on growth and performance in finishing cattle. The study compared feeding a typical background and finishing diet to two levels of consistent silage throughout the feeding period. The diet protocols were as follows:

  • 75 percent silage for 70 days followed by 15 percent silage until marketed (background/finishing)
  • 45 percent silage for the entire feeding period (high-silage finishing)
  • 15 percent silage for the entire feeding period (low-silage finishing)

The study showed that feeding the background/finishing diet resulted in similar growth and carcass characteristics as the high-silage diet. Laborie explains that these cattle had lower daily gains, poorer feed efficiency, and required 28 more days to reach a common backfat endpoint than those fed the low-silage diet.

The final body weight, carcass weight, and ribeye area were greater with the background/finishing diet and the high-silage diet. “Most importantly, this resulted in additional returns of $43 per head for cattle on the high-silage finishing diet and $27 per head for cattle fed the typical background/finishing diet,” Laborie notes. “Even with the additional days on feed, feeding 45 percent silage throughout the entire finishing period can be a profitable option for cattle feeders.”

As corn prices rise, take advantage of the accessible, cost effective feed resource corn silage provides when fed at elevated levels. “Feeding elevated levels of corn silage in finishing diets provides an opportunity for farmer feeders to take advantage of an accessible, cost-effective feed resource, especially when produced on their own acres,” Laborie concludes.

Michaela King

Michaela King served as the 2019 Hay & Forage Grower summer editorial intern. She currently attends the University of Minnesota-Twin Cities and is majoring in professional journalism and photography. King grew up on a beef farm in Big Bend, Wis., where her 4-H experiences included showing both beef and dairy cattle.