| In order to improve the fermentation quality and aerobic stability of Italian Ryegrass, after 7,14,21,30,60 days anaerobic fermentation and aerobic fermentation for 3 and 7 days,the effects of moisture contents(75% and 65%) and different additives(formic acid(LA),Lactobacillus plantment(LP),Lactobacillus buchneri(LB))on the fermentation quality and aerobic stability of Italian ryegrass were investigated. At the same time, the PCR-DGGE technology was used to detect the microbial population of 60 days and 7 days of aerobic.The results are as follows:1. During the 60 days conventional fermentation.formic acid group can quickly reduce the value of pH in the early stage of silage, and WSC decreased and ammonia nitrogen/total nitrogen(NH3-N/TN) increased a little, but because of inhibition of microbial activity,so lactic cid and acetic acid produced less during fermentation;Lactobacillus plantarum treatment,in the early Italian ryegrass silage (0-7 days),the consumption of WSC produces large amounts of lactic acid, and pH value is reduced to less than 4, then the pH decreased slightly, and the low values of pH inhibited the activity of protein enzyme,so the increase of NH3-N/TN is samll than the control group and Lactobacillus buchneri group; Lactobacillu buchneri group in the conventional silage process (0-60 days), PH has been higher than that of formic acid and Lactobacillus plantarum group, WSC decreased and NH3-N/TN rise is also rapid, especially in 21-60 days.Lactobacillus buchneri group not only produces lactic acid, also produced a certain amount of acetic acid, which will play a certain role in aerobic stability. For dynamic effects of water on the fermentation quality of Italian ryegrass silage, two moisture content of 75% and 65% both had no exudate,and even in the control group,it still can made good silage.Compared to the factor of additive, water contents(75% and 65%) on fermentation quality of Italian ryegrass silages impact smaller.2. During the aerobic period, each treatments had a very different effect on the aerobic stability, especially the different additives. Aerobic fermentation for 3 days, in two moisture conditions. pH value of formic acid and Lactobacillus buchneri group rise less than Lactobacillus plantarum and control group. Aerobic fermentation for 7 days.only Lactobacillus buchneri group, pH values remained below 5, and aerobic stability is much higher than other groups (more than 150h). To sum up. the aerobic stability of the ryegrass silage, Lactobacillus buchneri group> formic acid group> control group> Lactobacillus plantarum group.3. This experiment selects different treatments of Italian ryegrass silage for 60 days and 7 days of aerobic spoilage materials to extract the total DNA and analyzed the microbial population by using DGGE technology.The results showed that silage for 60 days,Lactobacillus buchneri is in the fermentation dominant position.Lactobacillus buchneri was detected in all the treatment group while the other groups detected the Bacillus. Aerobic fermentation for 7 days,each treatment were detected Enterobacteriaceae,but Lactobacillus buchneri in Lactobacillus buchneri treatment group still accounts for a dominant position.To sum up, in this experiment, two water contents(75% and 65%)can be made of high quality silage, but due to the long drying time will make forage nutrient loss more and the low water content is not conducive to the compaction problem.so controling the ryegrass water content in about 75% is suitable.And take the climate conditions in southern China and the actual production into count,water content 75% + formic acid and water content 75% + Lactobacillus buchneri are both effective ways to make high quality Italian ryegrass silage and keep aerobic stability. |
PDF Full Text Request