07/13/2026
🐄🥣 Finding the “Goldilocks” Chop Length for Dairy Cows
Just like Goldilocks searched for what was “just right,” dairy producers should aim for the ideal forage particle size in their lactating cow rations — not too coarse, not too fine.
Research examining swallowed feed particles during eating shows that the ideal particle size closely matches the material retained on the 8-mm sieve of the Penn State Particle Separator. To optimize cow performance, aim for:
✔️ 50%–60% of ration particles retained on the 8-mm sieve
Studies have shown that corn silage particles retained on the 8-mm sieve can increase:
• Chewing time
• Milk fat production
• Energy-corrected milk
Long particles on the top sieve should be kept to a minimum because cows can sort them out or take longer to consume them. Target:
✔️ 3%–5% of particles on the top sieve
To help prevent sorting, forage pieces should be no longer than 3 inches.
For the 4-mm sieve, recommendations suggest:
✔️ 10%–20% retained
Maintaining the proper balance helps support rumen health and feed efficiency.
Achieving the “Goldilocks” chop length requires attention throughout the harvest season. Consider:
🌽 Are your chopper settings producing the desired particle size?
🌽 Do settings need adjusted as moisture and forage fiber change?
🌽 Is your feeding equipment functioning consistently?
Paying attention to these details can help create the forage profile that Goldilocks—and your cows—would approve of.
For more information, check out Rick Grant’s article, “Precision Chewing Management: A Dynamic Approach to Forage Particle Size,” from the Miner Agricultural Research Institute.
Adapted from Hoards Dairyman Intel By Rick Grant Published 12/22/25
