Anhydrous Ammonia Injection Into Polyethylene Silage Bags to Enhance Forage Quality Attributes

Abstract

The injection of anhydrous ammonia (A-NH3) into bagged silage would allow variable applications of N to improve crude protein content of feeds. Trials evaluated the effectiveness of A-NH3 injection into silage for changes in nutrient characteristics and to evaluate animal preference. In Trial 1, A-NH3 was injected into a 30 t polyethylene bag of sorghum silage at 1% DM.  Injection was easily accomplished; the A-NH3 moved some vertically and horizontally, but movement was limited, likely due to excessive moisture in the silage.  In Trial II, polyethylene bags with 10 lb of forage were injected with 0, 1 or 2% A-NH3 on a DM basis and injected either pre-ensiling with or without corn or post-ensiling.  Silage quality was improved with higher levels of A-NH3.  Injection of A-NH3 during pre-ensiling stage of fermentation improved (P<.05) crude protein (CP) and NDF characteristics. Injection of A-NH3 during post-ensiling phase had no effect (P>.05) on characteristics, but A-NH3 volatilization losses occurred during injection. Holstein heifers fed various treated silage combinations showed no refusals, indicating acceptable silages. Treating silages with A-NH3 shows potential as a method of increasing CP of silages and improving diet digestibility, but issues of optimum moisture content in silages and timing should be addressed.