The Effect of Varying Mixing Ratios and Levels of Compression on the Fermentation Quality and Chemical Composition of Turf-type Ryegrass and Corn Silage

The objective of this study was to determine the influence of mixing a turf-type ryegrass (Lolium perenne) and corn (Zea mays) forage and applying different levels of compression on silage quality and chemical composition. Treatments were arranged as 5 x3 factorial following a completely randomi7ed design of experiment. Factors include the different mixing ratios of the two silage materials viz. ryegrass and corn at 100:0, 75:25, 50:50, 25:75, or 0:100, which were ensiled in quadruplicate in plastic drums (60L capacity) at varying compression levels (viz. 10, 20 or 30 bars). After 60 days of ensiling, nutrient composition and fermentation end products were evaluated. Regardless of compression level, silage from pure 100% ryegrass achieved the highest pH (4.90) and lowest concentration of lactic acid (0.64% DM). Mixing at least 25% corn with ryegrass lowered pH, increased lactic and acetic acid of the resulting silage than pure ryegrass alone. An interaction effect between mixing ratio and compression levels was observed only for pH and DM. Increasing compression level consequently resulted to silage with lower pH especially as more corn was added to ryegrass. Our findings show that the addition of corn (minimum of 25%) in ryegrass produced silage with better quality than pure ryegrass, and that increasing the compression level packed more DM in the silo and enhanced fermentation through lowered pH.