Submitted to: Corn Silage Production Management and Feeding
Publication Type: Experiment Station
Publication Acceptance Date: 5/26/1995
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: A wide variety of silage additives are being marketed to improve corn silage. The principal additives are bacterial inoculants, nonprotein nitrogen sources such as anhydrous ammonia and urea, enzymes, and organic acids such as propionic acid. The most common silage additive is the bacterial inoculant. Inoculants contain lactic acid bacteria and supplement the natural lactic acid bacteria on the crop to guarantee a fas and efficient fermentation in the silo. Inoculants are inexpensive, and so small gains in dry matter recovery from the silo and small improvements in animal performance can easily provide the financial incentive for their use. However, these products are not always successful in corn silage because of high natural levels of lactic acid bacteria on the crop. Anhydrous ammonia has been used commonly in making corn silage in some regions of the U.S. An alternative to ammonia is urea, which is more expensive. The primary reasons for using these additives are to increase the crude protein content of the silage and increase silage bunk life. Urea is better for raising crude protein content because of its more consistent, positive effect on animal performance. Anhydrous ammonia is more effective at improving bunk life. Enzymes are one of the newest classes of silage additives. These additives usually contain a variety of cell-wall and carbohydrate degrading enzymes: cellulases, hemicellulases, pectinases and amylases. However, there is insufficient evidence to indicate their effectiveness in corn silage. Propionic acid and mixtures of propionic acid and other acids such as acetic are used to reduce spoilage and increase bunk life. These products are effective when used at the recommended rates but are more expensive than many other additives.