Importance of Forage Quality

By: Karla Hernandez, forages field specialist at SDSU Extension

Livestock production depends largely on the feeding program; and what you should feed your animals will depend on an analysis of the forage quality. So, what is forage quality? It is the potential of forage to produce the desired animal response. It is measured by six main components: (1) palatability, (2) intake, (3) digestibility, (4) nutrient content, (5) anti-quality factors, and (6) animal performance. As procedures for analyzing forages have improved, knowledge of how to use test results to increase animal efficiency and performance has also improved. Despite these advances, many livestock producers do not recognize the full value of forage quality testing as a management tool.

Why should I test forages for quality? Many scientific studies have shown that the quality of forages fed can have a significant impact on net profit. For example, dairy producers who estimate the crude protein content of their haylage to be 3 percent units lower than it is, and the crude protein content of their corn silage 2 percent units lower than it is, end up feeding more supplemental protein than necessary. Knowing the quality of the forages you are selling or buying is economically wise as well and should been taken in consideration.

How do I collect a forage sample for quality testing?
Samples of Baled Hay:

1. Take a separate sample from each field and cutting.
2. Always sample with a bale core, otherwise, it is impossible to get representative samples.
3. Insert the sampler full depth into the end of each bale. This will insure an accurate sample.
4. Take at least 20 samples cored from each lot.
5. Mix the 20 cores in a clean bucket and place in a plastic bag.
6. Label each bag with your name, location, date, address, forage mixture, stage of maturity and date harvested.
7. Send your samples to a laboratory that analyses forage quality.

Samples of Haylage and Silage at Harvest:

1. Take a sample of the silage, collecting from three to five handfuls of silage or haylage from the first load of the day in a plastic bag, and place in refrigerator or freezer immediately.
2. Follow the same procedure for several loads of forage throughout the day and proceed to combine samples by mixing well, until you obtain a representative sample.
3. Repeat this process for each field if more than one field is harvested in one day.
4. Label the plastic bag with your name, address, sample number, forage mixture, stage of maturity, and date of harvested.
5. Send your samples to a laboratory that analyses forage quality.

Preparing and Storing Collected Samples:

1. Keep hay samples in a cool place, and keep the haylage and silage samples frozen. Then proceed to mail them or bring them to a laboratory early in the week, to prevent bacterial decay that might alter the final results.
2. The results will depend on the amount of sample taken as well as if it was collected randomly but with a good representation.

Summary: Proper sampling ensures that the forage analyses accurately reflect the hay, silage, or pasture being sampled. Generally, the better the growing conditions, the higher the forage quality. It is important to follow the steps to obtain a sample of forage in hay or silage, or else inadequate sampling will result in less accurate forage quality data analysis.

View the related publication below for a list of certified laboratories where samples can be sent for forage quality testing.

Related Publication
Feed Testing Laboratories by SDSU Extension