## 3 Results and Analysis
### Effects of Additives and Their Proportions on the Nutritional Quality of Corn Stover
#### 3.1.3 Effects of Different Treatments on the Fermentation Quality of Corn Straw Silage  
The fermentation quality of corn straw silage after 30 and 60 days of treatment with different additives is shown in Table 3. The interaction between different additives and silage duration significantly affected the pH, NH\({}_{3}\)-N, lactic acid (LA), and propionic acid (PA) contents (\(p<0.05\)). Silage duration significantly influenced the pH, LA, NH\({}_{3}\)-N, and PA (\(p<0.05\)), and different additives significantly affected the pH, NH\({}_{3}\)-N, LA, acetic acid \begin{table}
\begin{tabular}{l c c c c c c c c c c} \hline \hline  & **Time** & **CK** & **LP** & **LPCE1** & **LPXE1** & **LPCE2** & **LPXE2** & **SEM** & **T** & **D** & \(\mathbf{T\times D}\) \\ \hline DM\%FM & 30 d & 41.78 \({}^{\mathrm{A}}\) & 40.39 \({}^{\mathrm{A}}\)b & 40.22 \({}^{\mathrm{A}}\)b & 41.41 \({}^{\mathrm{A}}\)b & 40.67 \({}^{\mathrm{A}}\)b & 40.43 \({}^{\mathrm{A}}\)b & & \\  & 60 d & 41.37 \({}^{\mathrm{A}}\) & 39.84 \({}^{\mathrm{A}}\)b & 40.10 \({}^{\mathrm{A}}\)b & 40.82 \({}^{\mathrm{A}}\)b & 40.16 \({}^{\mathrm{A}}\)b & 39.06 \({}^{\mathrm{B}}\)c & 0.1624 & \(<\)0.0001 & 0.0349 & 0.8293 \\  & 30 d & 2.56 \({}^{\mathrm{A}}\)c & 3.31 \({}^{\mathrm{A}}\)b & 3.10 \({}^{\mathrm{A}}\)b & 3.00 \({}^{\mathrm{A}}\)b & 2.83 \({}^{\mathrm{B}}\)c & 3.42 \({}^{\mathrm{A}}\)b & & \\  & 60 d & 2.64 \({}^{\mathrm{A}}\)b & 3.22 \({}^{\mathrm{A}}\)a & 3.34 \({}^{\mathrm{A}}\)b & 3.38 \({}^{\mathrm{A}}\)a & 3.33 \({}^{\mathrm{A}}\)a & 3.42 \({}^{\mathrm{A}}\)b & & \\  & 30 d & 48.2 \({}^{\mathrm{A}}\)a & 47.76 \({}^{\mathrm{A}}\)a & 44.21 \({}^{\mathrm{A}}\)b & 45.02 \({}^{\mathrm{A}}\)b & 41.17 \({}^{\mathrm{A}}\)c & 43.84 \({}^{\mathrm{A}}\)b & & \\  & 60 d & 48.01 \({}^{\mathrm{A}}\)a & 47.64 \({}^{\mathrm{A}}\)a & 43.37 \({}^{\mathrm{A}}\)b & 42.97 \({}^{\mathrm{B}}\)b & 41.39 \({}^{\mathrm{A}}\)c & 43.31 \({}^{\mathrm{A}}\)b & & \\  & 30 d & 70.43 \({}^{\mathrm{A}}\)a & 70.31 \({}^{\mathrm{A}}\)a & 68.36 \({}^{\mathrm{A}}\)b & 65.84 \({}^{\mathrm{A}}\)c & 70.44 \({}^{\mathrm{A}}\)a & 64.82 \({}^{\mathrm{A}}\)c & \\  & 60 d & 69.26 \({}^{\mathrm{A}}\)b & 68.36 \({}^{\mathrm{B}}\)b & 67.62 \({}^{\mathrm{A}}\)b & 65.85 \({}^{\mathrm{A}}\)c & 69.57 \({}^{\mathrm{A}}\)c & 65.21 \({}^{\mathrm{A}}\)c & \\  & 30 d & 3.11 \({}^{\mathrm{A}}\)c & 4.14 \({}^{\mathrm{A}}\)c & 4.94 \({}^{\mathrm{A}}\)c & 5.50 \({}^{\mathrm{A}}\)c & 6.37 \({}^{\mathrm{A}}\)b & 7.01 \({}^{\mathrm{A}}\)a & & \\  & 60 d & 2.73 \({}^{\mathrm{A}}\)c & 1.96 \({}^{\mathrm{B}}\)c & 4.98 \({}^{\mathrm{A}}\)b & 5.35 \({}^{\mathrm{A}}\)b & 5.87 \({}^{\mathrm{A}}\)b & 7.17 \({}^{\mathrm{A}}\)a & 0.2534 \(<\)0.0001 & \(<\)0.0001 & 0.1011 \\ \hline \end{tabular} Note: (1) DM, dry matter; WSC, water-soluble carbohydrate; ADF, acid detergent fiber; NDF, neutral detergent fiber; CP, crude protein; FM, fresh material; CK, no additive; LP, materials. (2) Different lowercase letters within the same row show significant differences (\(p<0.05\)) between different treatments at the same ensiling duration; different capitalized letters within the same column show significant differences (\(p<0.05\)) between different ensiling lengths under the same treatment, whereas the same capitalized letters show no significant difference between treatments. T: different additive treatments; D: different ensiling lengths; T \(\times\) D: interaction between additive treatments and ensiling lengths; SEM: standard error of mean.  
\end{table} 
Table 2: Impacts of diverse added substances on the dietary quality of corn straw silage. (AA), and PA of corn straw silage (\(p<0.05\)). After 60 days of ensiling with additives, the NH\({}_{3}\)-N content was significantly lower than in the CK group (\(p<0.05\)). Compared with the CK group, the pH, LA, PA, and AA contents of the corn straw silage with additives were significantly lower after 60 days of ensiling (\(p<0.05\)). Additionally, butyric acid (BA) was not detected in any of the treatment groups.