Forage analysis of hay provides the nutrient content of the hay that you are feeding to your animals. Forage nutrient content varies between seasons, locations, cuttings, and storage conditions. By knowing the nutrient content of the hay, you can better manage the nutrition of your animals for better health and productivity.
Why Should I Perform a Hay Forage Analysis? Nutrient requirements of livestock vary with age, use, season and production status. Forages generally make up the primary feed of most livestock. Knowing the energy and protein content of forages is important to provide optimum nutrition for your animals. Forage analysis can also determine mineral levels in the forages. Different areas of the country have different availability of minerals in the soil and thus result in forages that may or may not meet the requirements of the animal for specific minerals. Knowing the nutrient content of your forages allows you to better tailor additional supplements to meet the needs of your animals.
How Do I Collect Hay Samples for Forage Analysis? The most important aspect of collecting a hay sample for forage analysis is obtaining a representative sample of the entire lot of hay. This means randomly sampling several bales and obtaining a representative sample from several bales. This often results in a composite sample that is not representative of the hay because of the over representing stems versus leaves. This is particularly true with alfalfa or alfalfa-mix hays.
Obtaining a Quality Sample of Hay for Forage Analysis
- Sample each "lot" or cutting of hay separately.
- Obtain core samples from at least 20 bales selected at random throughout the entire lot. If there are less than 20 bales, take multiple cores from all of the bales until you have 20 core samples
- Collect core samples from the side of the bale that is most resistant to puncture. For square bales, sample from the small ends. For round bales, sample from the side.
- Drive the entire probe into each bale.
- Empty the core chamber into the collection canister (multi-bore probes) or into your collection bag (single-bore probes) between each bale.
- Send the sample to the lab the same day or as soon as possible.
- Hart Forage Sampler: Harge Machine Company, Madras, OR 541-475-3107
What do the forage results mean? The most basic forage nutrient analysis evaluation factors help estimate intake, digestibility, available energy and available protein in the forage. This is critical for proper feeding to support maintenance needs, growth, and production in the animal. The results are generally reported on a dry matter basis so that forages can be appropriately compared independent of their moisture content. Additional tests can also be performed to determine mineral content and sometimes vitamin content of the forage.
- Moisture: The percent of the forage that is water. For hay, this generally runs between 5-15%. Moisture dilutes out the nutrient value of the forage on an as fed basis.
- Dry Matter (DM): The percent of the forage that is not water. For hay, this is typically around 87-95%. Feeds with lower DM require higher as fed intake to deliver the same amount of nutrients.
- Acid Detergent Fiber (ADF): A measure of the cellulose and lignin and leaves out the more digestible hemicelluloses. ADF is a predictor of digestibility of the hay. As ADF increases, digestibility decreases. A normal range in hay is 25 to 45% on a DM basis. Ideally for alpacas, this number has a value less than 30%.
- Calcium (Ca)
- Potassium (K)
- Manganese (Mn)
If your hay has a protein or TDN value below the recommendation for the production group, then you will want to either use different hay for that group of animals or consider supplementing those animals with another high TDN or protein supplement, or both. Feeding the proper hay to specific production groups to meet their dietary needs will help prevent both low and high body condition. It can also save you in feed costs so that you know what animals specifically need additional supplementation rather than always feeding these supplements to all animals.
Also remember that energy needs increase during times of higher physical activity or cold temperatures (winter). So, hay that may be doing just fine during the summer months may not provide sufficient nutrition for an animal in the winter.
Camelid TDN and Protein requirements for different sates of production based on 1.5-2.0% BW dry matter intake per day.