EFFECTS OF A BACTERIAL HAY PRESERVATIVE (PEDIOCOCCUS-PENTOSACEUS) ON HAY UNDER EXPERIMENTAL STORAGE-CONDITIONS

The abundant growth of molds and thermophilic actinomycetes in stored hay decreases its quality and can be hazardous for the producer who in hales these contaminants when the moldy hay is fed in closed barns, Th ese microbes are responsible for a respiratory disease called farmer's lung, Products, including bacterial cultures that can be inoculated i n hav, are available to prevent hay deterioration by molds and bacteri a, The aim of this study was to verify the effectiveness of Pediococcu s pentosaceus (a bacterial inoculant) in preventing hay deterioration at different humidity levels in a laboratory experiment. Mixtures of g rasses (mostly alfalfa, timothy, and clover) placed in plastic bags we re treated with the commercially available product (live culture of P. pentosaceus) at 500,000 and 5,000,000 CFU/g of hay and humidified at different levels (20, 25, 30, and 35%), Control batches of hay (untrea ted) were prepared at the same humidity levels. The growth of inoculat ed bacteria in hay, pH level, and hay deterioration were evaluated, Un der these experimental conditions, the growth of P. pentosaceus was ab undant only when it was inoculated in very moist hay (35% moisture), r esulting in bacterium levels of 6.3 x 10(8) CFU/g after 30 days, This abundant growth did not prevent the pH from increasing (final pH of ab out 9.0), nor did it prevent molding, rit lower humidity levels (20, 2 5, and 30%), the bacterial inoculant used did not grow and did not pre vent hay deterioration.