Representative Sampling of Horse Hay for Analysis

In an attempt to find a low-carbohydrate hay to feed their overweight horses, many owners consider having their hay analyzed by a commercial laboratory. To do so, they may stuff a few handfuls of hay into a plastic bag, send off the sample to a lab, and get some results back. However, obtaining a true representative sample of a batch of hay is the first and most critical step of the analysis process. Unfortunately, it is often the most overlooked.

A laboratory can only analyze what it receives, and it will analyze a good sample in the same way as a poor sample. In the latter case, the horse owner will wind up with a good analysis of a bad sample. Thus, it is the responsibility of the horse owner to obtain a representative sample.

Nutrient values will vary from bale to bale within a load of hay, so submitting one sample from a single bale may not give an accurate representation of an entire batch of hay. A better idea is to collect samples from a number of bales and combine them for analysis. This practice will give a better picture of the quality of a particular supply of hay.

In practice, it is not uncommon for people to sample one to three bales. If, by chance, the poorest bale is selected, ration recommendations would result in overfeeding. In contrast, selection of a superior bale would give different numbers, leading to underfeeding. Both situations will have nutritional and economic consequences, as feed cost is typically one of the largest expenses on any livestock operation. Thus, if you are willing to invest the time, effort, and dollars in forage analysis to better formulate rations, it is in everyone’s best interest to do the best job possible of obtaining a representative sample.

The greater the number of subsamples, the better the analysis will be in representing the nutrient profile for that batch of hay. In reality, sampling 10 to 12 bales should provide a good representative sample.