Skip to Content

The Weekly News Source for Wyoming's Ranchers, Farmers and AgriBusiness Community

Feeding rates: Feed analysis helps avoid over- or under-feeding livestock

by Wyoming Livestock Roundup

With abundant forage supplies expected this year, producers can afford to be more selective purchasing their winter feedstuffs. Despite cheaper prices for hay, livestock ranchers should still have a forage analysis conducted so they can get the most bang for their buck.

Hay producers may also want to consider having a hay analysis completed to use as a marketing tool in a buyer’s market.

According to Rick Rasby, Extension beef specialist with the University of Nebraska, producers would be surprised how much forages can vary in nutritional value.

Samples taken

Rasby discussed samples he had taken at a stack yard on alfalfa and native grass hay.

“We sampled a stack yard of alfalfa, and it ranged from 13 percent to 23 percent crude protein. The native hay ranged from four percent to ten percent crude protein,” he explained.

The National Research Council (NRC) requirements suggest alfalfa averages 15 percent crude protein and 56 percent total digestible nutrients (TDN), and native hay typically averages six percent crude protein and 52 percent TDN.

If a forage has 52 percent TDN, it will be difficult for that forage to meet the cow’s nutritional requirements after calving by feeding it alone.

“As we move closer to 56 percent TDN, the forage may be able to meet the cow’s nutrient requirements prior to calving, but we may need to add a little energy after calving to meet her nutritional requirements because they will be higher,” he explained.

“What is important to note from all of this, is not all forages are average,” Rasby continued. “That is why it is important to get our forage analyzed and why it is important to collect a good sample.”

Taking the sample

Producers can access videos through the University of Nebraska’s YouTube channel, NU Beef, to learn how to sample hay. These videos show samples being taken from a big round bale, and from a pile of ground hay. They also give step-by-step instructions for the sampling process.

“It is very important when sampling hay to get a representative sample,” Rasby explained. “Don’t take grab samples on forages.”

“Producers will need to use a hay probe, which can usually be borrowed from their local county Extension office,” he explained.

Representative sampling

Rasby said if a producer has 20 to 25 big round bales of hay, 10 to 12 of those should be sampled to get a good, representative sample. When sampling hay, never sample first, second, third and fourth cuttings of hay together.

“All of those should be separate samples,” he said. “Early cut and late cut hay should also be sampled separately, as well as different varieties like sorghum-sudan grass hay and millet hay.”

After the samples are taken, it is important to identify the sample properly, so the lab analyzing the sample has a good understanding of what is in the bag.

“The forage analysis will only be as good as the sample we have taken,” he said.

Typically, most forages are analyzed in the lab using near-infrared spectroscopy (NIR), which is a quick and accurate way to identify the nutrients in the forage.

Results can typically be received within two to three days of sending a sample in, if producers send it at the first of the week.

Gayle Smith is a correspondent for the Wyoming Livestock Roundup. Send comments on this article to

Back to top