Early detection and assessment: How to prevent microbial spoilage in your TMR

When Total Mixed Ration (TMR) begins to heat or spoil, it's already impacting your bottom line. Microbial activity - primarily from yeasts and molds—can silently reduce feed quality, lower dry matter intake, and compromise herd health and productivity. But by identifying the warning signs early, you can act fast to protect your ration.

Why early detection matters

Microbial spoilage often starts in silage and continues once mixed into the TMR. Early intervention allows you to:

  • Maintain feed intake and milk yields
  • Reduce waste and heating at the feed bunk
  • Avoid the knock-on effects of mold and yeast growth on herd health

Key indicators of spoilage risk

Keep an eye out for:

  • Unexpected heating of both silage and TMR (check both surface and internal temperatures)
  • Sweet, alcoholic, or sour odors
  • Visible mold or discoloration in the silage or TMR
  • Elevated pH or temperature differences within the feed 

Simple assessment steps

  • Visual and sensory check: Use smell, touch, and appearance to spot early signs of instability.
  • Temperature testing: A >5°C difference between surface and core in the TMR can indicate active microbial growth.
  • Infrared cameras or probe thermometers: Quickly pinpoint hotspots and monitor stability over time.
  • For more precise analysis, laboratory testing provides detailed insights

For a complete guide on testing methods to evaluate spoilage risk of your silages and TMR, check out our latest technical brochure.

Don’t wait for waste

Testing your feed—even just with basic tools—can reveal hidden risks and help avoid costly spoilage. Combine that with the right preservative strategies to get the most out of your TMR every day.