Abstract: This research evaluated fermentation quality of silage made from Broussonetia papyrifera and rice straw mixed in various proportions, with or without additives. B. papyrifera and rice straw were mixed in ratios by fresh weight of 10∶0 (Group A), 9∶1 (Group B), 8∶2 (Group C), and 7∶3 (Group D). The fermentation quality and nutritional quality were analyzed after 60 days fermentation with no additive (CK), or addition of molasses (T), lactobacillus (GLP5), or molasses and lactobacillus (T+GLP5). Compared with the CK silages, the pH value and ammonia nitrogen∶total nitrogen ratio of the T and, T+GLP5 silages were significantly decreased (P<0.05), and the lactic acid content was significantly increased (P<0.05). The GLP5 treatment significantly lowered (P<0.05) the pH and ammonia nitrogen∶total nitrogen ratio compared to CK, but less so than the T treatments. As expected, neutral and acid detergent fiber and cellulose and hemicellulose concentrations increased and crude protein fell with increasing proportion of rice straw. In general, for a given proportion of rice straw, additive treatments ranked CK>GLP5>T>T+GLP5 for fiber and cellulose levels and the opposite for crude protein, although some interactions between mixture proportion and additive occurred. In summary, the T and T+GLP5 silages with added molasses and a 9∶1 mixing ratio of B. papyrifera and rice straw are optimal for silage making with these materials.

Key words: Broussonetia papyrifera, rice straw, molasses, lactic acid bacteria