Improving cow performance while consuming low-quality forage
Published on Jan. 18, 2020
“The last few years have been challenging in regards to hay quality, forage growth and animal management,” states Dr. Travis Mulliniks, University of Nebraska-Lincoln (UNL) beef cow nutritionist, during the Nov. 8 episode of UNL’s BeefWatch podcast. “This year was a really wet year. A lot of hay didn’t get put up, and most of the hay that was put up was pretty low quality on average.”
Because of this, Mulliniks emphasizes how important it is for producers to get their forage quality tested and to assess their cattle’s body condition score (BCS) as they move through the winter and into calving season.
“Those two things really help producers strategically decide what to supplement to have the best impact and decrease cost while moving through the winter and preparing the cows for calving in the spring,” he says.
Protein versus energy supplementation
The two main things producers need to pay attention to in regards to forage quality are protein and energy content, according to Mulliniks.
He explains during late gestation energy requirements increase with increased fetal growth. Because of this, cattle may be lacking in energy versus protein, even though it is more common for them to be protein deficient.
Mulliniks points out this is especially the case when cows are a little thinner than normal.
“As we move through the winter and closer to calving, maintaining cows’ BCS is imperative during this critical time,” he says. “Producers don’t want to get behind the ball when the weather starts getting really cold and wet because cows can lose BCS very rapidly. They don’t want to get into a situation where their cattle are sacrificing body reserves.”
He continues, “If this is the case, they need to intervene with an energy supplement, primarily a fiber energy supplement because maintaining BCS is crucial to get those cows ready for calving.”
Mulliniks suggests distiller’s grains as an effective fiber energy supplement. He also notes cottonseed meal and alfalfa hay are decent options as well.
“A starch or corn-based supplement needs to be fed daily,” Mulliniks says. “Distiller’s grains, on the other hand, can be fed more infrequently and still have the same outcome as feeding it every day.”
“When it comes to protein supplementation, anything less than seven percent crude protein is considered a low-quality forage,” explains Mulliniks. “At seven percent or below, crude protein starts limiting the rumen microbe population so they need additional protein to help break down and utilize energy from forages.”
“Forage with a crude protein content of nine to 12 percent is high quality and is adequate for mature cows to meet their requirements for late gestation,” he continues.
“A good rule of thumb for mature cows is to feed them three percent of the protein source. So if we have a supplement with 30 percent crude protein, we feed one pound a day to meet their daily requirements of protein,” Mulliniks states.
He further explains for younger females, first and second calvers, this should be increased to five or six percent.
Sources of protein
According to Mulliniks, there are few different sources of protein to consider when supplementing cattle – rumen degradable protein, rumen un-degradable protein and urea.
“The degradable protein will be broken down by rumen microbes and alter the amino acids,” he explains. “The un-degradable version, on the other hand, will bypass rumen microbe degradation, and then we have urea, which is non-protein nitrogen.”
Mulliniks says the problem with urea is that when it is fed, cattle will undergo a quick spike in utilization.
“Some forages may stay in the rumen up to 72 hours, especially in low-quality forage situations,” he explains. “If we have a quick spike in microbe activity, the cow isn’t going to be able to utilize the urea correctly to help break down the forage. It really is a wasted energy source for those cows.”
Mulliniks stresses a supplement higher in urea may cause issues because cattle can’t utilize it correctly.
“What we have found from our data at UNL, is supplements higher in rumen un-degradable protein are the most effective in increasing forage digestibility and intake, and therefore, maintaining BCS,” Mulliniks states.
Calculating costs
The last thing Mulliniks discusses is considering cost per pound of protein.
“Producers need to think about what the cheapest form of protein to meet their cattle’s daily requirements is in their area,” he says.
He notes the same is true for energy.
“Producers need to look at it from a cost per pound of energy perspective versus cost per ton of feed,” Mulliniks explains. “Cost per ton is deceiving because a producer may be buying something that is cheaper but they have to feed more of it to meet the requirements for their cattle. If they buy their protein source on a cost per pound of energy basis, they might have to pay more per ton but they don’t have to feed as much.”
Hannah Bugas is the assistant editor for the Wyoming Livestock Roundup. Send comments on this article to roundup@wylr.net.