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Interpreting hay analysis results

% Moisture and % Dry Matter

When deciding whether to buy a batch of hay, its moisture content is perhaps the single most important number. In fact, it can be a make-or-break number, as hay with too high a moisture content does not store well and is prone to mold. That's important not only for horses with heaves (commonly known as COPD, more appropriately called asthma), but for every horse. Moldy hay increases the risk for problems involving the respiratory, digestive, reproductive, and immune systems, and the eyes. It also increases wastage, as moldy hay is not as palatable as 'clean' hay.

When selecting a hay, choose one with a moisture content of 10% or less. Another way of saying the same thing is that the dry matter content should be 90% or more. (% Moisture + % Dry Matter = 100%.)

% Moisture and % Dry Matter

Digestible Energy (DE)

Crude Protein and Estimated Lysine

Fiber - Lignin, ADF, and NDF

Carbohydrates - WSC, ESC, Starch, and NFC

Major minerals - Calcium, Phosphorus, Magnesium, etc.

Trace minerals - Iron, Zinc, Copper, etc.


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