Abstract
Compounds or ingredients have been added to feeds when stored in an attempt to improve or prevent deterioration of the stored product. An understanding of changes occurring during storage is necessary in order to properly evauate any additive. When high moisture forage is compacted and kept anaerobic, it is then stabilized by microbial production of lactic acid. Addition of fermentable carbohydrate such as molasses, simple sugars or whey produces silage with lower pH, less proteolysis and increased lactic acid formation when compared to control silage. Addition of sufficient amounts of organic acids reduces pH immediately which inhibits fermentation and reduces dry matter loss and proteolysis. Formic acid has been used successfully with direct cut forage. Propionic acid and ammonium isobutyrate added to forage when ensiled has increased remaining fermentable carbohydrate, and has reduced proteolysis, fungal numbers, dry matter loss, heating and formation of indigestible protein. Formaldehyde, formate salts, Na2SO4, Na2S2O5, SO2 and many other chemicals have not met with continued success as silage additives. Addition of antibiotics has not consistently improved silage. Addition of microbial cultures under laboratory conditions may improve silage characteristics, but in field trials there has been no benefit. Growth of undesirable bacteria during ensiling can be prevented by a low pH or increasing dry matter content to above 30%. Wilting the forage after cutting or spraying with dehydrating chemicals before cutting has produced desirable silage. In the U.S. excellent hay-crop silage can be produced by following recommended procedures; the additional use of additives available to date will have little effect on the ensuing silage. Propionic acid and ammonia may be useful mold inhibitors with baled hay. Copyright © 1978. American Society of Animal Science . Copyright 1978 by American Society of Animal Science.