By Jay Jenkins, UNL Extension Educator
The reason we put up hay is to feed livestock. When we feed animals we are not just feeding "feed." We are supplying nutrients needed for the animal to grow, renew body components, form products such as milk and wool, and furnish energy for all of the processes involved. The major nutrients involved are energy, primarily in the form of carbohydrates, and protein. The animal also needs various vitamins and minerals, as well as water. Necessary vitamins and minerals are easily provided should the main feedstuffs be lacking.
Hay, and grain for that matter, is fed as a primary source of energy and protein. Therefore it makes sense that the value of the hay is relative to the amount of these nutrients that it contains. The more protein and energy that is in the hay, the more valuable the hay is to the feeder. The converse is also true, the lower the nutrient content, the less valuable.
This is true within certain limits, the value differences may be different for different classes of livestock. Under certain circumstances the nutrient content of the hay may be low enough that certain classes of livestock cannot eat enough to get the nutrients required, therefore that feed is actually worthless to that feeder. It may also be possible that under some circumstances a certain level of nutrients is "high enough" and any additional the hay supplies may be of no additional value. But under most circumstances where there is a wide variety of feed uses and feeds available, the statement holds true:
The higher the nutrient content the higher the value and the lower the nutrient content the lower the value.
As you can see it is essential than a nutrient analysis be done. It is impossible to determine relative values between hay without knowing its nutrient content. Nutrient analysis is relatively cheap and easy to obtain. When given a choice of hays, the smart hay buyer always demands an analysis be done. This helps ensure he/she is getting what he/she is paying for. The nutrients we will concern ourselves with for the purpose of this discussion are protein and energy. It is also important to remember that hays differ in their moisture content, this is usually reported as percent Dry Matter (DM). It is important to account for this difference as well. Protein is designated on most analysis as Crude Protein (CP), and the easiest measure of energy to use is Total Digestible Nutrients (TDN), these are both reported as a percent of dry matter.
One concept that helps determine value differences between various lots of hay is to determine the cost per pound of the major nutrients. For example let’s consider two lots of hay.
Lot 1: 89.3% DM, 16% CP, 51.6% TDN, $100/Ton, $.35/lb CP, and $.109/lb TDN
Lot 2: 90.5% DM, 22.8% CP, 71.5% TDN, $145/Ton, $.351/lb CP, and $.112/lb TDN
Comparing hay by the cost per pound of nutrient only tells part of the story. Although the two hays above are priced similarly, which one would be the better choice depends on the circumstances. For a beef producer feeding dry pregnant cows, Lot 1 may be preferred. The cows could get full and not be overfed. But for a dairy producer, Lot 2 would be the logical choice, because it would allow higher levels of milk production than Lot 1.
Cost per pound of nutrient works not only for comparing the value of hay, but it also works when pricing different grains or supplements. Protein supplement is often fed to cows on winter range, and crop aftermath. This concept works great for comparing the value of those as well. For example:
22% Cake: 22% CP, $208/Ton, $.437/1b CP
28% Cake: 28% CP, $233/Ton, $.416/1b CP
Alfalfa Hay: 18% CP, $180/Ton, $.556/1b CP
One underlying premise that we haven't talked about yet is that feed should not only be bought according to nutrient content, but that it should also be fed according to nutrient content. This requires knowing not only the nutrient content of the feed, but also the requirements of the animal. There are published values that will give you a good idea of what your animals need. It is often necessary to mix feeds to most economically match nutrients fed to nutrients required.
The Feed Cost Cow-Q-Lator (http://westcentral.unl.edu/agecon3) makes comparing feed costs easy.
Hay should be analyzed for nutrient content. This allows it to be bought, sold, and fed according to its nutrient content. The more facts you know about the hay the better job you can do comparing prices and determining rations.