Knowing the nutritional value of forages can help reduce feed costs
Cattle producers are looking at their hay supply for the colder months. For some, that means it’s time to start considering the purchase of hay, but is all hay the same?
The answer is simply, no.
For example, the University of Missouri Extension states that Missouri ranks fairly high in the nation in hay production, but that hay is not always the greatest quality. Missouri excels in cool season grass or fescue hay, but falls around 20th in the say of high-quality hay production, such as alfalfa.
No matter what type of hay a producer buys or feeds, it should be tested.
Why is hay testing important?
Forages furnish essential energy, proteins, vitamins, minerals and fibers in livestock diets.
Factors such as variety, maturity, growing conditions, handling practices and so on affect forage quality prior to the time it is fed, according to Oklahoma State University Extension. Without proper testing, producers can overestimate or underestimate the feed value of forages. The lower the quality, the more supplementation will be needed, resulting in added costs.
Feed costs, according to the MU Extension account for 60 percent of a beef cow enterprise, so knowing the quantity and quality of hay fed to livestock directly affects the bottom line.
What’s in a test?
A typical hay test will analyze for moisture, protein, fiber and various minerals.
Moisture is the amount of water in the sample. Most hay samples run in the 10 to 15 percent moisture range, according to MU Extension.
The hay test report includes a column called “As-is” or “As-fed” and another column called “Dry Matter.”
Dividing the as-fed number by the percentage of dry matter in the sample converts the results to a dry matter basis. Using the dry matter basis results allows for accurate comparison between wetter vs. drier feeds because the water content of the hay or silage is excluded from the reported dry matter nutrient results.
Crude protein, the item most producers seem more concerned about, is estimated by measuring the amount of nitrogen in the sample and multiplying it by 6.25. This factor is used because most forage stem and leaf tissue proteins contain 16-percent nitrogen. Higher crude protein is usually better, but must be considered in the context of plant maturity, species, fertilizer rate and nitrate concentrations.
Another major aspect of a hay test is the fiber analysis.
Information from MU Extension states that forage samples are boiled in either a neutral detergent or acid detergent solution. After boiling, some of the sample disappears (the digestible portions) and some remains (the indigestible portions).
The residues are reported as Acid Detergent Fiber (ADF) and Neutral Detergent Fiber (NDF). NDF provides an estimate of forage intake while ADF is used to calculate estimated energy levels in the forage. These energy estimates are listed as Total Digestible Nutrients (TDN), Net Energy maintenance and Net Energy gain. Since both NDF and ADF results are residues, lower numbers indicate greater intake potential and higher energy levels. The lower the ADF and NDF, the better.
Finally, there’s the mineral analysis. Calcium and phosphorus are typically included in a hay test package from the labs. Some labs also include potassium and magnesium in their hay test packages.
For additional fees, other minerals can be measured. Labs vary in cost and the analysis provided.
For more information about forage testing, contact your local Extension Center.
