Interpreting hay analysis results
The laboratory I use and recommend for hay (and other feed) analysis is Equi-Analytical. They allow horse owners as well as veterinarians to submit samples of hay, pasture, and other feed for analysis. On the right is an example of the results they provide, in this case for a sample of timothy hay (a second cutting from 2016).
I'll go through some key components of the report and provide ideal ranges for the average adult horse who is not pregnant or lactating, focusing on the average horse's maintenance needs.
Before we begin, the submission form can be downloaded here. In most cases, you'll need to fill in only the first page. (In fact, I generally don't bother printing the second page.) The analysis package I most often recommend is 601, Equi-Tech (the second option under the heading Hay and Pasture).
(You'll notice that this article is all about grass hays. Except for the first few months of life, grasses should form the bulk of the horse's diet. When pasture grazing is limited for any reason, grass hay, whether from a bale or a bag [hay pellets, cubes, chopped forage, or haylage], should fill the gap.)
Click on the components below for details on interpretation:
Example of a hay analysis report: a second-cutting timothy hay, harvested in 2016. These results are for the Equi-Tech (601) analysis package offered by Equi-Analytical Laboratories.