Introduction

Having hay analyzed is the only way to determine the actual nutrient content of it. It is important to know this so that you can be sure your horse is consuming an adequate diet. There may or may not be a need to feed grain depending on the quality of the hay.  The better the quality of the hay, the less grain you will need to feed, which can be a significant savings. Analyzing will allow you to feed the horse more effectively and efficiently. 

Types of Analysis

Two types of analyses can be performed; visual and chemical. If you have already purchased hay, then you have probably performed a visual analysis. Chemical analysis is when the hay is sampled and the nutrient content of the hay is determined by a laboratory.  

In visual analysis, there are several factors that should be considered. These include:  

• Maturity of hay 

• The more mature, or older, a hay is, the more fiber it contains, and the more stemmy or unpalatable it will become  

Table 1.  Example of stages of maturity of alfalfa hay (NRC 1989)  

• Leafiness of the hay 

• • The more leaves a hay has, the more nutrients it is likely to contain since nutrients are concentrated in the leaves (where photosynthesis occurs)  

• Color of the hay; generally the greener, the better, see Table 1. 

• Odor and condition of the hay 

• • look for hay that is not musty, dusty, or moldy; throw out any hay that is  

• Presence of foreign materials in the hay  

• • can be injurious (poisonous plants, wire) or non-injurious (weeds), but either decreases the overall quality of the hay.   

In order to have hay analyzed chemically, you will need to provide a hay sample. Use a core sampler and try to sample from at least 20-25 different bales. Be sure to penetrate into the center of the bale with the core sampler.  

Visit the local county extension office for information on how to use the core sampler (or to borrow one) if you do not have experience in hay sampling. Mix the samples together and then put them in a tight, clean, plastic bag, or the bags that the forage testing lab provides. Mail it to the forage testing lab as soon as possible, in order to have it analyzed by the laboratory.  

Interpreting the results in the hay analysis report may not be the easiest part of this process. If you cannot determine what the results mean, you may want to consult an extension specialist in forage crops or agronomy at the local county extension center, an animal scientist, or a county extension agent.   

Some of the main things to focus on when you see the analysis reports are:  

• Dry Matter (DM) – This tells you how much of the sample is left after water is removed, it is the moisture or dry matter content of the sample.  Hay will generally be about 89% dry matter or greater.  

• Digestible energy (DE) – This is a measure of the digestible energy in the hay. For a light working horse, DE should be 20.5 Mcal/day.  Hay may have .76 to .94 Mcal/lb or higher of DE.  

• Total Digestible Nutrients (TDN) – This is a measure of the total digestible nutrients in the hay or its energy value (may be used in place of DE or offered in addition to DE), which may range from 40 to 55 percent.  

• Crude Protein (CP) – This is a measure of the protein concentration of the hay and can range from six to eight percent in native grass hays to about 15% or higher in high quality legume hays.  

• Neutral Detergent Fiber (NDF) – This is a measure of the plant’s cell wall content, shown as a percent.  The higher this is, the less the horse will eat of the hay.  

• Acid Detergent Fiber (ADF) – This is a measure of the fiber concentration of the hay, shown as a percent. As ADF increases, digestibility and nutrient availability decreases.  

• Non Structural Carbohydrates (NSC) – This is a measure of the non-structural carbohydrates in the feed. If your horse has Cushing’s disease or is prone to colic or laminitis, select hay with a lower NSC value. Timothy and alfalfa hay may have a 15% or 20% NSC value, respectively. If you want this analysis done, check to see if the lab offers it, as it is not a common analysis at this time.  

• Starch and Sugar – This is a measure of sugars and starches in the feed. You should feed no more than 15% of total daily calories from starch and sugar to horses with EPSM (equine polysaccharide storage myopathy) and PSSM  (polysaccharide storage myopathy).  

EPSM is a muscle disease found in over 100 draft breeds that may cause severe weakness and muscle wasting in horses of all ages, poor performance, abnormal hind limb gaits, and shivers (in which the muscles keep twitching). PSSM is a muscle disease found in horses with Quarter Horse in their breeding such as American Quarter Horses, Paints, and Appaloosas, with signs including reluctance to move, muscle stiffness, sweating, shifting lameness, and tremors in the flank area.  

Below is what analysis of good hay should resemble:  

Resources

National Research Council.  Nutrient Requirements of Horses. (1989). National Academy Press, Washington, D.C.  

Vough, Lester R. Evaluating hay quality (2000). Online fact sheet, FS-644, University of  

Maryland.  Available online at: http://www.agnr.umd.edu/MCE/Publications/Publication.cfm?ID=110  

Wright, Bob W. Hay, haylage and treated hay for horses. (Sept. 2004) Online fact sheet. Ontario Ministry of Agriculture and Food.  

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