Forage Quality Testing

Forage quality testing is laboratory analysis of forage samples for nutrient content. It’s the foundation of accurate ration formulation — without recent forage analysis, every ration calculation is built on assumed values that may not match what’s actually in the bunker.

The standard test panel for corn silage and haylage:

• Dry matter (DM) — moisture content; the basis for everything else.
• Crude protein (CP) — nitrogen × 6.25; total protein.
• Neutral detergent fiber (NDF) — total cell wall content; the structural fiber.
• Acid detergent fiber (ADF) — less digestible fiber; correlates with energy.
• Starch — for corn silage and grains; the energy backbone.
• Sugars / WSC — water-soluble carbohydrates, important for fermentation.
• Mineral panel — Ca, P, K, Mg, S, micros.
• NDF digestibility (NDFd) — how much of the NDF is actually digested in 30 hours; an emerging top-tier metric.

Most operations test post-harvest (to set the opening assumptions for the year) and quarterly thereafter as silage is fed out. Industry references:

• Dairy One — Northeast US, very common.
• Dairyland Labs — Midwest US.
• Cumberland Valley Analytical Services — Mid-Atlantic / national.

Forage quality testing is the input nutritionists need to formulate accurate rations. It pairs naturally with silage inventory measurement — quality data tells you what you have, inventory data tells you how much.