Dry‐matter losses and changes in nutrient concentrations in grass and maize silages stored in bunker silos

Abstract

To reduce losses and improve forage use efficiency in dairy farming systems, mass and nutrient flows during silage production have to be measured from the field to feed bunk. However, data on these losses at the farm scale are scarce. Thus, we examined dry‐matter (DM) losses and changes in nutrient concentrations (proximate constituents, nitrogen [N], phosphorus [P]) and energy values (net energy for lactation [NEL]) of silages on three experimental farms from ensiling to feed‐out. The investigated material included forages from permanent grassland and whole‐crop maize that were stored in 64 side‐walled bunker silos. To determine DM losses, the total‐in versus total‐out method was applied. Additionally, the changes in the nutrient concentrations were measured by comparing the concentrations before and after ensiling. Data analyses were carried out by using ANOVA, and the means across groups were compared via multiple contrast tests. On average, the farms had good silage production management. Average values showed a trend towards higher DM losses during the ensiling process with grass (9%) than maize (7%). The N and P concentrations of the silages remained mainly unchanged during the ensiling process, suggesting that the total losses of N and P were also low (<10%). Regarding the fibre fractions, ensiling resulted in a significant reduction in the concentration of amylase‐treated ash‐excluded neutral detergent fibre (aNDFom) for grass (11%) and maize (15%), while ash‐excluded acid detergent fibre (ADFom) was not affected by the ensiling process. These changes resulted in slightly improved energy values in the silages.

Investigation of co-ensiling for the storage of grain stillage and Jerusalem artichoke residue from inulin extraction

“…There was a slight increase in the overall compositions of NDF, ADF, ADL, CL, and HC. Stable ADL and decreased fiber compositions, i.e., NDF, ADF, CL, and HC, were reported by Köhler et al (2019) and Dong et al (2020), who co-ensiled grass with maize and Broussonetia papyrifera with perennial ryegrass, respectively. The ADF content in this study was found to gradually decrease in the M5, M6, and M7 samples.…”

“…The WSC content for all substrates decreased considerably in the first 10 d of ensiling due to microbial degradation. Afterwards, it fluctuated slightly until the end of the ensiling process, which could be due to the decomposition of starch and/or structural carbohydrates, i.e., hemicellulose and cellulose, by microbes and/or acids produced additional soluble carbohydrates to compensate for the consumed WSC (Köhler et al 2019).…”

Ensiling Techniques for Whole-Plant Sunflowers (Helianthus annuus) and their Nutritive Values for Ruminants in Vietnam

“…How-ever, Nguyen et al (2005) reported no difference in dry matter content of Orchard grass before and after ensiling. Similarly, Gerlach et al (2018) and Köhler et al (2019) also reported no difference in DM content of corn and grass silages. In the initial aerobic exchange stage, aerobic microorganisms continue to work with the remaining oxygen in the incubator.…”

“…Data in Table 8 shows that, NDF of CTL treatment was significant (P<0.05) difference between day 0 and day 21, whereas significant (P>0.05) differences were not showed in other treatments The result of NDF value was consistent with the hemicellulose content (by calculated the NDF-ADF content) of sunflower at 1.8% (Table 2). Some studies have reported that the silage often reduced the NDF content (Gerlach et al, 2018;Köhler et al, 2019), the result of the structural carbohydrates being hydrolysed by enzymes in the ensilage. However, Köhler et al (2019) showed that the decrease in NDF content was due to the reduction of hemicellulose, meaning that the ADF content did not decrease after incubation.…”

“…Some studies have reported that the silage often reduced the NDF content (Gerlach et al, 2018;Köhler et al, 2019), the result of the structural carbohydrates being hydrolysed by enzymes in the ensilage. However, Köhler et al (2019) showed that the decrease in NDF content was due to the reduction of hemicellulose, meaning that the ADF content did not decrease after incubation. This could be due to the chemical structure of the sunflower, the time of harvest as well as the microbial activity of the silage.…”