Don't jump the gun when feeding your new-crop corn silage. Feeding a crop that hasn't properly fermented can lower dry matter intake (DMI), decrease milk production, and cause digestive upsets. Allowing time for adequate fermentation creates a more palatable and digestible feed for optimum DMI and milk production.
Traditionally, nutritionists have recommended allowing silage to ferment for three to four weeks before feeding, although recent research from Cumberland Valley Analytical Services Inc. (CVAS) indicates waiting longer may increase silage digestibility. The CVAS study showed that corn silage continued to ferment for four months after ensiling.
"The common misconception is that silage is stable after four weeks," said Kathy Emery, veterinarian and Mycogen Seeds dairy nutritionist. Actually, starch and fiber digestibility continue to improve for up to four months."
Emery provides these reminders when preparing to feed a new silage crop:
• Oxygen is the enemy of quality silage. During feedout, prevent the penetration of air into the silage. Ensure the face is smooth-shaven to minimize the surface area exposed to air.
• Allow silage to ferment a minimum of four weeks before feeding; wait longer if possible.
• If you anticipate that you may have to feed the new crop sooner, consider using a bacterial inoculant to help drop the pH of the silage rapidly and improve the overall fermentation. An optimum fermentation will lower dry matter losses and preserve nutrients in the silage. Follow label directions for dilution and application and do not allow liquid inoculants to heat in the sun.
• Plan ahead to ensure you aren't forced to feed silage that hasn't properly fermented. Manage your inventory and, if possible, have carryover feed available.