## 4 Discussion
### Effects of KF and LP on Silage Quality  
pH is an important parameter to evaluate the extent of silage fermentation [29]. A lower pH reduces undesirable fermentation and ensures better aerobic stability. In the present study, the pH value of forage rape silage without additives was 4.84, much higher than the benchmark pH of 4.20 for well-fermented silage [10]. This is a common problem with the natural ensiling of high-moisture silage. According to the current study, the pH value of the additive-treated groups was close to or below 4.20, indicating good preservation  
Figure 3: Comparison of bacteria variations using LÉSe analysis. CK: the control; KF: konjac flour; LP: _Lactiplantiobacillus plantarum_; KFLP: konjac flour + _Lactiplantiobacillus plantarum_.  
of high-moisture forage rape. The decreased silage pH contributes to the inhibition of undesirable microbes, thus helping to preserve the forage mass [30]. This is consistent with the reduced abundance of enterobacteria and clostridia according to the 16 s rRNA gene sequencing. Lactic acid is the dominant fermentation product in silage, which is another important evaluation index of fermentation quality. In this study, the additive-treated groups promoted the production of lactic acid, which was the main reason for pH reduction.  
LAB inoculants, including LP, are widely used to produce high-quality silage [8; 16]. Similar to the present study the LP inoculation was found to decrease the pH value and accelerate the fermentation of lactic acid in high-moisture alfalfa and Napier grass silage, according to [PERSON] et al. [18] and [PERSON] et al. [31]. However, little is known about the effectiveness of KF as a silage additive. KF is a water-soluble dietary fiber that displays very high water-holding capacity, good swelling, thickening, and gelation-property [14; 32]. Consequently, KF is increasingly used as a stabilizer and emulsifier for processed foods, beverages, and cosmetic products [14; 32]. Based on the present study, KF helps improve the fermentation quality of high-moisture forage rape, possibly by inhibiting water activity. Furthermore, the contents of isobutyric acid and butyric acid were decreased in additive-treated groups. Isobutyric acid is an oxidation product of amino acids [33]. Butyric acid is undesirable in silage as its generation is an energy-waste metabolism [10]. When butyric acid exceeds 5 g/kg DM, it indicates substantial clostridial activity and will impair livestock feed intake [10]. In this study, the content of butyric acid in the treated silages was decreased to a very low level, which might be due to the inhibition of clostridial fermentation caused by KF and LP.  
The addition of KF, either alone or in combination with LP, decreased the CP content in forage rape silages. This could be explained by the lower CP content of KF compared with forage rape (80 g/kg vs. 144.5 g/kg). In addition, the alteration of microbial activities might result in a difference in nutrient preservation. According to the current study, the NDF content in LP inoculated silages was lower than that in KF treated silages. Similarly, [PERSON] et al. reported that during the 60-d ensiling process, both NDF and ADF contents were decreased in high-moisture alfalfa treated with a commercial LAB [8]. In addition, in the silage of wilted perennial ryegrass, an inoculant containing LP, _L. buchneri_ and _L. casei_ also reduced the NDF content after ensiling for 60 days and 150 days [34]. It may be due to the fact that LP promotes microbial degradation, which converts plant cell walls into complex sugars during ensiling [35].