# Quality of Maize Silage After Using Meat Bone Meal as a Phosphorus Fertilizer in a Field Experiment
## 3 Results
### Fermentation Parameters and Feed Value of Maize Silage  
The rate of LA fermentation was similar in all treatments regardless of fertilization and year of the study (Table 4). Significant differences were noted in AA concentration in maize silage, which was significantly higher in the zero-fert treatment than in 1.0 Mg MBM + N\({}_{79}\) and 1.5 Mg MBM + N\({}_{40}\) treatments (\(p\leq 0.01\)). The silages differed also in the concentrations of VFAs, and significant differences were found between the zero-fert treatment and the 1.5 Mg MBM + N\({}_{40}\) treatment (\(p\leq 0.05\)). Fertilization-induced differences in the content of PDIE in maize silage were evaluated according to the INRA system (\(p\leq 0.05\)). The silages  
Figure 1: Interaction effect of fertilization and year of the study on the phosphorus content of maize silage; a, b within a year (\(p\leq 0.05\)). \begin{table}
\begin{tabular}{l c c c c} \hline
**Treatment (t)** & **P** & **K** & **Ca** & **Mg** \\ \hline Total average & 1.85 \(\pm\) 0.05 & 12.2 \(\pm\) 0.68 & 1.18 \(\pm\) 0.09 & 0.97 \(\pm\) 0.011 \\ \hline
1. Zero-fert & 1.90 \(\pm\) 0.07 & 11.2 \(\pm\) 0.89 & 0.86 \({}^{\rm B}\)\(\pm\) 0.14 & 0.90 \({}^{\rm B}\)\(\pm\) 0.12 \\
2. Inorganic NPK & 1.73 \(\pm\) 0.05 & 12.2 \(\pm\) 0.86 & 1.44 \({}^{\rm A}\)\(\pm\) 0.19 & 1.00 \({}^{\rm a}\)\(\pm\) 0.15 \\
3. 1.0 Mg MBM + N79 & 1.83 \(\pm\) 0.09 & 12.0 \(\pm\) 1.21 & 1.02 \({}^{\rm B}\)\(\pm\) 0.17 & 0.91 \({}^{\rm b}\)\(\pm\) 0.12 \\
4. 1.5 Mg MBM + N40 & 1.96 \(\pm\) 0.06 & 12.4 \(\pm\) 1.24 & 1.07 \({}^{\rm B}\)\(\pm\) 0.16 & 0.94 \({}^{\rm ab}\)\(\pm\) 0.13 \\
5. 2.0 Mg MBM & 1.84 \(\pm\) 0.07 & 13.5 \(\pm\) 1.19 & 1.49 \({}^{\rm A}\)\(\pm\) 0.14 & 0.95 \({}^{\rm ab}\)\(\pm\) 0.13 \\ \hline  & 2014 & 2.05 \({}^{\rm a}\)\(\pm\) 0.04 & 8.4 \({}^{\rm C}\)\(\pm\) 0.35 & 1.05 \(\pm\) 0.19 & 1.15 \({}^{\rm A}\)\(\pm\) 0.04 \\ Annual mean (y) & 2019 & 1.78 \({}^{\rm b}\)\(\pm\) 0.05 & 15.3 \({}^{\rm A}\)\(\pm\) 0.59 & 1.14 \(\pm\) 0.13 & 0.95 \({}^{\rm B}\)\(\pm\) 0.05 \\  & 2020 & 1.73 \({}^{\rm b}\)\(\pm\) 0.05 & 13.4 \({}^{\rm B}\)\(\pm\) 0.41 & 1.35 \(\pm\) 0.04 & 0.81 \({}^{\rm B}\)\(\pm\) 0.05 \\ \hline Interaction (t \(\times\) y) & \multicolumn{2}{c}{s \({}^{1}\)} & ns \({}^{2}\) & ns & ns \\ \hline  & & & & \\ \end{tabular}  
* \({}^{1}\) s—significant; \({}^{2}\) ns—not significant. Values marked with the same letters in columns, within factors are not significantly different: a, b at \(p\leq 0.05\); A, B, C at \(p\leq 0.01\).  
\end{table} 
Table 3: Macronutrient content (g-kg\({}^{-1}\) DM) of maize silage (mean \(\pm\) standard error of mean). made in inorganic NPK and 1.0 Mg MBM + N\({}_{79}\) treatments were characterized by higher PDIE content than those made in zero-fert and 2.0 Mg MBM treatments (\(p\leq 0.01\)). Differences in silage acidity were observed between years of the experiment. The silage made in 2019 had a significantly higher pH than those produced in 2014 and 2020 (\(p\leq 0.05\)). The silage made in 2014 had the highest concentrations of AA, BA, and VFAs, and the lowest PA content (\(p\leq 0.05\)). The silage produced in 2019 had the highest concentrations of AA and PA, and significantly lower concentrations of BA and VFAs (\(p\leq 0.05\)). The silage made in 2020 had the lowest concentrations of AA, BA, and VFAs, and the highest PA content (\(p\leq 0.05\)). The energy value of maize silage varied across the years of the study. The values of UFL and UFV were highest in 2014 (\(p\leq 0.01\)). The silage made in 2019 was characterized by the lowest energy value, 0.87 UFL and 0.76 UFV (\(p\leq 0.05\)). The PDIE content and energy value were significantly highest in the silage made in 2014 (\(p\leq 0.01\)). No interaction between the experimental factors was found for the analyzed fermentation parameters or the feed value of silage, determined according to the INRA guidelines.