The biological silage additive, Safe-Sile, is a commercial product prepared by Microferm Ltd. and the objective of the experiment was to appraise its efficacy in the conservation of silage and its subsequent feeding value.

Safe-sile contains lactic acid bacteria (2.5 x 109 cfu/g consisting of proportionately 0.75 Lactobacillus plantarum and 0.25 Pediococcus acidilactici) together with enzymes (hemicellulase, amyloglucosidase and cellulase) and a mixture of bacteriophages (2.5 x 109 pfu/g). These active ingredients are carried in dextrose together with mineral salts, trace elements and vitamins.

Two silages were made in September 1988 from third-cut wilted grass, one silage receiving no additive (control treatment) and the other receiving Safe-Sile at the rate of 1 kg per 15 tonnes of grass approximately. The fields harvested for this experiment were perennial ryegrass/white clover swards and the silages were made after a field wilting period of 24 hours under good silage-making conditions.