Effect Of Adding Citric Acid Residue On Fermentation Quality And Aerobic Stability Of Rice Straw Silage

The Jiangsu region is rich in by-product resources such as rice straw and citric acid residue,but these resources have not been rationally utilized for a long time.Rice straw is characterized by low nutritional value and poor palatability.Direct feeding of livestock is difficult to meet the nutritional needs of livestock production;by-products such as citric acid residue have high nutritional value and moisture content,and difficult to be Long-term preservation.Mixing rice straw and citric acid residue into high-quality silage with soft texture,good palatability and high nutritional value can make up for the shortcomings of both,it is also an effective measure to realize the feed utilization of by-product resources such as rice straw and citric acid residue.1.Effects of different proportions of citric acid residue on fermentation quality and aerobic stability of rice straw silageThe purpose of this experiment was to investigate the effects of different proportions of citric acid residue on the fermentation quality and aerobic stability of rice straw silage.The test was conducted with control group(Sck),1.2%citric acid residue group(Scl),2.4%citric acid residue group(Sc2),and 3.6%citric acid residue group(Sc3).Samples were analyzed for fermentation quality and aerobic stability after 3,6,9,15,30 and 45 days during ensiling.The results showed that compared with the control group,the pH value and ammonia nitrogen/total nitrogen value of the treatment group were lower(P<0.05),and the lactic acid content was higher,and the difference between the treatment groups was not significant(P>0.05).There were no significant differences in dry matter,neutral detergent fiber and acid detergent fiber content between the groups at the end of ensiling stage(P>0.05).Among them,the pH value of the Sc2 treatment group decreased the fastest,the ammonia nitrogen/total nitrogen value was lower,the lactic acid accumulation was the fastest,and the fermentation quality was the best.After 2 days of aerobic exposure,the pH and ammonia nitrogen of each group continued to rise,and the lactic acid and water-soluble carbohydrates continued to decrease.Compared with the other groups,the temperature of the Sc2 group increased by 2℃ for the longest time.Considering the fermentation quality and aerobic stability,the addition of 2.4%citric acid residue is most suitable.2.Effects of different proportions of citric acid residue and molasses on fermentation quality and aerobic stability of rice straw silageThe purpose of this experiment was to investigate the effects of different proportions of citric acid residue and molasses on the fermentation quality and aerobic stability of rice straw silage.The test consisted of control group(Sck),molasses group(SM),1.2%citric acid residue and molasses group(Scl+M),2.4%citric acid residue and molasses group(Sc2+M),3.6%citric acid residue and molasses group.(Sc3+M).Samples were analyzed for fermentation quality and aerobic stability after 3,6,9,15,30 and 45 days during ensiling.The results showed that compared with the control group,the treatment group had lower pH value(P<0.05),higher lactic acid content(P<0.05),and lower ammonia nitrogen/total nitrogen value(P<0.05),but there was no significant difference between the treatment groups(P>0.05),and there were more water-soluble carbohydrates remaining at the end of ensiling stage.Among them,the Sc3+M group had the lowest pH value,the highest lactic acid content,and the ammonia nitrogen/total nitrogen value was lower,and the fermentation quality was the best.After 2 days of aerobic exposure,the pH and ammonia nitrogen of each group continued to rise,and lactic acid and water-soluble carbohydrates continued to decrease.Compared with other groups,the temperature of Sc3+M group increased by 2 ℃ for the longest time.Considering the fermentation quality and aerobic stability,3.6%citric acid residue and molasses are added in the most suitable combination.3.Effects of different proportions of citric acid residue and lactic acid bacteria on fermentation quality and aerobic stability of rice straw silageThe purpose of this experiment was to investigate the effects of different ratios of citric acid residue and lactic acid bacteria on the fermentation quality and aerobic stability of rice straw silage.The test consisted of control group(Sck),lactic acid bacteria group(SL),1.2%citric acid residue and lactic acid bacteria group(Scl+L),2.4%citric acid residue and lactic acid bacteria group(Sc2+L),and 3.6%citric acid residue and lactic acid bacteria group.(Sc3+L).Samples were analyzed for fermentation quality and aerobic stability after 3,6,9,15,30 and 45 days during ensiling.The results showed that compared with the control group,the pH value of the treatment group was below 4.2(P<0.05),and the lactic acid content was higher(P<0.05).The addition of lactic acid bacteria could reduce the ammonia nitrogen/total nitrogen value in the early stage of silage fermentation.(P<0.05).Among them,the Sc3+L treatment group contained higher lactic acid content and lower ammonia nitrogen,and the fermentation quality was the best.After 2 days of aerobic exposure,the pH value and ammonia nitrogen of each group continued to rise,and the lactic acid and water-soluble carbohydrates continued to decrease.Compared with the other groups,the temperature of the Sc3+L group increased by 2℃ for the longest time.Considering the fermentation quality and aerobic stability,3.6%citric acid residue and lactic acid bacteria are the most suitable combination.4.Effects of citric acid residue and organic acid additives on fermentation quality and aerobic stability of rice straw silageThe purpose of this experiment was to study the effects of citric acid residue and organic acid additives on the fermentation quality and aerobic stability of rice straw silage.The effects of adding citric acid residue and four organic acids(sorbic acid,acetic acid,propionic acid,formic acid)on the fermentation quality and aerobic stability of rice straw silage were discussed.The test consisted of control group(Sck),2.4%citric acid residue group(Sc2),0.1%sorbic acid group(SS),0.4%acetic acid group(SA),0.3%propionic acid group(SP),and 0.4%formic acid group(SF),after 45 days of fermentation,samples were analyzed for fermentation quality and aerobic stability.The results showed that the four organic acids(sorbic acid,acetic acid,propionic acid,formic acid)treatment group,the pH value was higher than that of the citric acid residue group(P<0.05),and the lactic acid content was lower than that of the citric acid residue treatment group(P<0.05).The ammonia nitrogen/total nitrogen value was lower than that of the citric acid residue group(P<0.05).There was no significant difference between other indexes(P>0.05),indicating that the four organic acids have certain improvement effects on the fermentation quality of rice straw,among which formic acid has the best effect,followed by acetic acid and propionic acid,but the effect is not as good as citric acid residue.The pH value and ammonia nitrogen/total nitrogen value of the organic acid group did not change much during the whole aerobic exposure.The consumption rate of lactic acid and water-soluble carbohydrates was lower than that of the citric acid residue group,and the time required for the temperature of the organic acid group to rise by 2℃ is much longer than that of the control group and the citric acid residue group,indicating that the four organic acids are superior to the citric aeid residue in improving the aerobic stability of the rice straw silage,the sorbic acid and acetic acid are the best,the formic acid is the second.