Effect of preservatives in moist hay

Field-dried hay must be sufficiently dry at harvest for problem-free storage. Alternatively, preservatives that prevent heating and spoilage may be added to the hay. In a trial, the efficacy of various microorganisms (lactic acid bacteria, yeasts and enzymes) as well as of a product containing various acids was tested in moist hay with a DM content of 75 % on a laboratory scale. The positive control with propionic acid was the only one preventing the heating and deterioration of the hay. The variants with different microorganisms or a chemical product were not effective: the forage heated, and was highly mouldy at the end of the test.