Glossary · Silage
Silage Shrink
The percentage of silage dry matter lost between harvest and feedout. Industry averages run 5-20%; top operations stay under 10%.
Silage shrink is any loss between dry matter put up at harvest and dry matter actually fed to cows. It’s the gap between what you measured at the chopper and what reaches the bunk.
Industry estimates put typical shrink between 5% and 20%, with some operations exceeding 30%. Top-quartile operations run under 10%.
Shrink happens at every stage:
- Harvest — moisture, length of cut, inoculant choice all affect how the pile will ferment.
- Ensiling — packing density, cover quality, filling speed determine how much oxygen the pile sees during fermentation.
- Feedout — defacing technique, surface spoilage, feeder accuracy all subtract from what cows get.
The economics are large. Every percentage point of feed-system shrink reduction recovers exactly 1% of the annual feed bill. On a 2,500-cow dairy carrying ~$6M of feed cost, dropping shrink from 15% to 10% is $300,000 of recovered margin every year — without buying an acre or selling a pound of milk. On a 1,500-cow dairy with ~$3.8M of feed cost, the same 5-point cut is ~$190,000.
The first step is measurement. See: The Importance of Measuring Silage Shrink and the silage shrink calculator.