VFA And Ammonia-Nitrogen Analysis

880 Words4 Pages
Short chain volatile fatty acids and ammonia-nitrogen analysis
From each incubation bottle, 5 mL of supernatant was collected and stored for analysis of VFA and ammonia-nitrogen. For VFA analysis, samples were centrifuged in Sorvall Centrifuge (SL-50 T, 8×50 ml) at 25,000g for 15 min at 4° C and a part of the supernatant was transferred to a micro-centrifuge tube (capacity 1.5 mL) containing meta-phosphoric acid (250 g/L), (5 g/L) as internal standard. The standard VFA mixture consisted of acetic, propionic, butyric, isobutyric, valeric and isovaleric acids and was treated in the same manner as that for the sample. The VFA’s in test sample were analyzed by the gas chromotaphore (GC) with FID analyzer and it was calibrated against the standard.
…show more content…
The values are presented in the Table1. Eragrostis trichopophora has a low CP concentration while its NDF component is relatively high. The chemical composition of the browse species
Table 1: Chemical composition of Eragrostis trichopophora (g kg-1 DM)
Ash OM CP EE NDF ADF ADL NDIN Cellulose
33.1 919.7 34.3 9.5 794.9 477.7 67.9 21.0 409.8

OM = organic matter CP = crud protein EE = ether extract NDF = neutral detergent fiber ADF = acid detergent fiber ADL = acid detergent lignin NDIN- neutral detergent insoluble nitrogen, Cellulose calculated as (ADF-ADL)

In vitro enteric methane production
In the current study, the in vitro methane production as shown in Table 2 indicates that after 24 h of incubation, there was significant differences (p<0.001) lower in substrates without PEG compared to the browse grass-substrates with PEG. The lower ratios for CH4: GP24, CH4: VFA and CH4: IVOMD that were observed for A. luederitzii is partly due to A. luederitzii having higher fermentation properties compared to the other browse grass-substrates, but is also related to the tannin concentrations that reduced CH4

More about VFA And Ammonia-Nitrogen Analysis

Open Document