Glossary
Dairy feed measurement, term by term.
Definitions for the metrics and concepts that show up in dairy feed conversations — silage measurement, ration formulation, bunk management, and the cow-health observations that connect them.
Silage
Aerobic Stability
How long silage resists heating and spoilage after exposure to oxygen. A direct predictor of feedout-period shrink.
Bunk Silo
A horizontal, open-faced storage structure for ensiling forage — concrete walls with an exposed feedout face. The dominant silage storage form on US dairies. Often called a 'bunker silo'.
Fermentation Loss
Dry matter lost during the fermentation phase of ensiling, primarily from microbial activity converting sugars to volatile compounds.
Silage Density
Pounds of dry matter per cubic foot of silage. The factor that converts pile volume to tonnage, and a leading indicator of fermentation quality.
Silage Shrink
The percentage of silage dry matter lost between harvest and feedout. Industry averages run 5-20%; top operations stay under 10%.
Feed
Dry Matter (DM)
The portion of feed that remains after all water is removed. The unit dairies use to compare and ration feeds, because moisture content varies widely.
Dry Matter Intake (DMI)
Pounds of dry matter a cow consumes per day. The single largest controllable driver of milk production on a dairy.
Feed Efficiency (FE)
Pounds of fat-corrected milk produced per pound of dry matter consumed. The single best metric for dairy nutrition performance.
Forage Quality Testing
Lab analysis of forage samples for nutrient content (NDF, ADF, CP, starch, sugars). The foundation of accurate ration formulation.
Physically Effective Fiber (peNDF)
The portion of fiber that is long enough to stimulate chewing and rumen function. Measured with the Penn State Particle Separator.
Total Mixed Ration (TMR)
A complete dairy ration where forages, grains, and supplements are blended into one feed before delivery to the bunk.
Feed Bunk
Drones
Drone Dairy
Informal term for a dairy operation that uses drones as part of regular workflow — typically for silage inventory measurement, crop scouting, pasture management, or facility planning.
Ground Control Points (GCPs)
Surveyed reference markers placed on the ground during a drone flight. The single largest factor in drone-based silage volume accuracy.
Photogrammetry
The science of measuring real-world objects from photographs. The technical foundation of drone-based silage volume measurement.