This experiment was conducted to study the effect of molasses on the fermentation characteristics of mixed silage ensiled rice straw and vegetable by-products with alfalfa.Mixture（202 g kg^-1 dry matter（DM））consis...This experiment was conducted to study the effect of molasses on the fermentation characteristics of mixed silage ensiled rice straw and vegetable by-products with alfalfa.Mixture（202 g kg^-1 dry matter（DM））consisting of rice straw,broccoli residue and alfalfa at the ratio of 5：4：1 was ensiled with three experimental treatments：（1）no additives（control）;（2）molasses at 2.5%（M1）;（3）molasses at 5%（M2）on a fresh matter basis of mixture,respectively.All treatments were packed into laboratory-scale silos,and three silos per treatment were sampled on days 1,3,5,14 and 30.The result showed that the p H value of all mixed silages decreased gradually with the time of ensiling except for the control silage,in which a significant increase（P〈0.05）on day 30 occurred.The lactic acid content increased gradually with the time of ensiling and reached the highest value on day 14,and a marked decrease（P〈0.05）was found in the control silage on day 30.The changes of acetic acid content showed similar pattern with lactic acid content.A trace amount of propionic and butyric acid contents were found in the three mixed silages during the fermentation period.Comparing to the control,M1 and M2 treatments improved the fermentation quality of mixed silages as indicated by higher（P〈0.05）lactic acid contents and lower（P〈0.05）p H and ammonia-N contents.The Flieg points also showed that M1 and M2 silages were well preserved,whereas the control silage had a bad quality.Overall,the findings of this study suggested that adding molasses could improve fermentation quality of mixed silage,and M1 was more suitable for practical application.展开更多
This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aer- obic stability and in vitro gas production kinetics and digestibility of whole-crop corn bas...This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aer- obic stability and in vitro gas production kinetics and digestibility of whole-crop corn based totalmixed ration （TMR） silage. Total mixed ration was ensiled with four treatments： （1） no additives （control）; （2） an inoculant （Lactobacillus plantarum） （L）; （3） propionicacid （P）; （4） propionic acid＋lactic acid bacteria （PL）. All treatments were ensiled in laboratory-scale silos for 45 days, and then subjected to an aerobic stability test for12 days. Further, four TMR silages were incubated in vitro with buffered rumen fluid to study in vitro gas production kinetics and digestibility. The results indicated that all TMR silages had good fermentation characteristics with low pH （〈3.80） and ammonia nitrogen （NH3-N） contents, and high lactic acid contents as well as Flieg points. Addition of L further improved TMR silage quality with more lactic acid production. Addition of P and PL decreased lactic acid and NH3-N contents of TMR silage compared to the control （P〈0.05）. After 12 days aerobic exposure, P and PL silages remained stable, but L and the control silages deteriorated as indicated by a reduction in lactic acid and an increase in pH, and numbers of yeast. Compared to the control, addition of L had no effects on TMR silage in terms of 72 h cumulative gas production, in vitro dry matter digestibility, metabolizable energy, net energy for lactation and short chain fatty acids, whereas addition of PL significantly （P〈0.05） increased them. L silage had higher （P〈0.05） in vitro neutral detergent fiber digestibility than the control silage. The results of our study suggested that TMR silage prepared with whole-crop corn can be well preserved with or without additives. Furthermore, the findings of this study suggested that propionic acid is compatible with lactic acid bacteria inoculants, and when used together, although they reduced lactic acid production of TMR silage, they improved aerobic stability and in vitro nutrients digestibility of TMR silage.展开更多
基金supported by the project of Jiangsu Independent Innovation, China (CX(15)1003-3)the Key Technologies R&D Program of China during the 13th Five Year Plan period (2016YFC0502005)the special project of grass of Tibetan Autonomous Region for the “13th FiveYear” Plan, China
文摘This experiment was conducted to study the effect of molasses on the fermentation characteristics of mixed silage ensiled rice straw and vegetable by-products with alfalfa.Mixture（202 g kg^-1 dry matter（DM））consisting of rice straw,broccoli residue and alfalfa at the ratio of 5：4：1 was ensiled with three experimental treatments：（1）no additives（control）;（2）molasses at 2.5%（M1）;（3）molasses at 5%（M2）on a fresh matter basis of mixture,respectively.All treatments were packed into laboratory-scale silos,and three silos per treatment were sampled on days 1,3,5,14 and 30.The result showed that the p H value of all mixed silages decreased gradually with the time of ensiling except for the control silage,in which a significant increase（P〈0.05）on day 30 occurred.The lactic acid content increased gradually with the time of ensiling and reached the highest value on day 14,and a marked decrease（P〈0.05）was found in the control silage on day 30.The changes of acetic acid content showed similar pattern with lactic acid content.A trace amount of propionic and butyric acid contents were found in the three mixed silages during the fermentation period.Comparing to the control,M1 and M2 treatments improved the fermentation quality of mixed silages as indicated by higher（P〈0.05）lactic acid contents and lower（P〈0.05）p H and ammonia-N contents.The Flieg points also showed that M1 and M2 silages were well preserved,whereas the control silage had a bad quality.Overall,the findings of this study suggested that adding molasses could improve fermentation quality of mixed silage,and M1 was more suitable for practical application.
基金supported by the project of Jiangsu Independent Innovation,China(CX(15)1003-3)the Key Technologies R&D Program of China during the 13th Five-Year Plan period(2016YFC0502005)the Special Project of Grass of Tibet Autonomous Region for the 13th Five-Year Plan,China
文摘This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aer- obic stability and in vitro gas production kinetics and digestibility of whole-crop corn based totalmixed ration （TMR） silage. Total mixed ration was ensiled with four treatments： （1） no additives （control）; （2） an inoculant （Lactobacillus plantarum） （L）; （3） propionicacid （P）; （4） propionic acid＋lactic acid bacteria （PL）. All treatments were ensiled in laboratory-scale silos for 45 days, and then subjected to an aerobic stability test for12 days. Further, four TMR silages were incubated in vitro with buffered rumen fluid to study in vitro gas production kinetics and digestibility. The results indicated that all TMR silages had good fermentation characteristics with low pH （〈3.80） and ammonia nitrogen （NH3-N） contents, and high lactic acid contents as well as Flieg points. Addition of L further improved TMR silage quality with more lactic acid production. Addition of P and PL decreased lactic acid and NH3-N contents of TMR silage compared to the control （P〈0.05）. After 12 days aerobic exposure, P and PL silages remained stable, but L and the control silages deteriorated as indicated by a reduction in lactic acid and an increase in pH, and numbers of yeast. Compared to the control, addition of L had no effects on TMR silage in terms of 72 h cumulative gas production, in vitro dry matter digestibility, metabolizable energy, net energy for lactation and short chain fatty acids, whereas addition of PL significantly （P〈0.05） increased them. L silage had higher （P〈0.05） in vitro neutral detergent fiber digestibility than the control silage. The results of our study suggested that TMR silage prepared with whole-crop corn can be well preserved with or without additives. Furthermore, the findings of this study suggested that propionic acid is compatible with lactic acid bacteria inoculants, and when used together, although they reduced lactic acid production of TMR silage, they improved aerobic stability and in vitro nutrients digestibility of TMR silage.
