グリーンパニック

The effect of addition of different carbohydrate sources on the quality of high-moisture green panic (Panicum maximum var. trichoglume) silages was studied. Second cut herbage at heading stage was chopped (about 2 cm). The material was treated with glucose (2, 4 and 8% wet wt), glucose and starch together (glucose+ starch: 2+2.1 and 4+4.2%), starch (4.2 and 8.4%) and ground corn (11%), respectively. The materials including control (without additive) were ensiled in 2-liter polyethylene silos attached with Bunsen's bulbs. Silage samples with two replications (silos) were taken out at 55 days after ensiling. Values of pH and organic acids, ammoniac nitrogen (NH_3-N) and total nitrogen (T-N) contents of silage samples were determined. And T-N, TNC, starch, total sugars (TS) and dry matter (DM) contents of plant materials and silage samples were determined. The material without additive (control), which contained ca. 4% of TNC and ca. 25% of DM, did not produce well-preserved silage. Addition of starch or glucose+starch increased total nonstructural carbohydrates (TNC) content in the material ensiled up to almost the same levels of equivalent glucose additions (4 and 8%). Addition of ground corn increased TNC level in the material ensiled and the level showed between the glucose addition of 4 and 8%. When TNC contents of the materials ensiled were increased up to ca. 11, 17 and 27% of DM by additions of 2, 4 and 8% glucose, respectively, the additions of glucose markedly improved silage quality, having low pH and NH_3-N and high lactic acid and no butyric acid. The increase in glucose added to the materials increased amount of lactic acid in the silages, but additions of glucose decreased efficiencies of total organic acids production to consumed TNC during storage. When the amount of additives adujusted to almost the same level of equivalent TNC in the materials, the additions of glucose+starch were less effective than those of glucose and were more effective than those of starch alone. The effect of the addition of 11% ground corn on lactic acid fermentation was almost equivalent to that of the 4% glucose addition. The starch consumption during storage was ca. 50% of the original in three treatments with starch addition and TS consumption ranged ca. 60-100% of the original in all silages.