Manure content, color and consistency are predictors of rumen digestion
Manure consistency is often considered by producers and farm advisers as a predictor of rumen digestion. Different aspects are usually taken into account when observing manure consistency (Hutjens M. F. 2010), (Kononof P., Heinrichs J., and Varga G).
Content
When the presence of large portions of undigested, but processed, grain and/or forage particles are visible in manure, it may be an indication of poor rumen fermentation. Low rumen pH (which impairs rumen microflora activity) coupled with a high passage rate, can lead to a reduction of starch and fiber digestion in the rumen.
The presence of large amounts of undigested grain may be an indication of:
- Improper processing (i.e. hard kernels from corn silage) or
- Poor rumen digestion (even if well-processed). This could be due to inadequate fiber intake, which stimulates rumination and maintains optimal rumen pH.

Manure with visible grain and/or large forage particles
Color and Consistency
An example of non-optimal rumen digestion is when: finely ground grain passes quickly through the rumen, which can appear as a yellow color in dried manure; this grain can ferment in the lower gut inducing a mucus layer on the surface of the manure, which is a sign of chronic inflammation or injury to the gut tissue.
Manure that contains bubbles or foam may indicate acidosis or excessive hindgut fermentation, which causes gas production.

Manure consistency scale
FAQ About Rumen Development
- Low rumen pH (acidosis)
- Inadequate fiber intake
- Poor feed processing
- High passage rate of digesta
- Excessive fermentable carbohydrates in the diet
- Increase effective fiber in the diet
- Ensure proper grain processing
- Maintain consistent feeding schedules
- Monitor and manage rumen pH
- Use manure scoring as part of routine herd health checks