An in vitro nutritive evaluation and rumen fermentation kinetics of Sesbania aculeate as affected by harvest time and cutting regimen

Abstract

The nutritive value of Sesbania aculeate harvested after 60 and 120 days of planting and subjected to two cutting regimen (15 or 30 cm length) was evaluated by determination of the crude protein (CP), crude fibre (CF), buffer soluble nitrogen (BS-N), buffer soluble non-protein nitrogen (BS-NPN) and cell wall constituents (neutral-detergent fibre; NDF, acid-detergent fibre; ADF and lignin). In vitro digestible organic matter (IVDOM), metabolizable energy (ME), microbial nitrogen (MN) and biomass (MBM) production were also estimated in the experimental plant samples after their incubation with rumen fluid for 96 h in the absence or presence of polyethylene glycol (PEG, 6000) at a ratio of 2:1 PEG:substrate. Fermentation characteristics (initial gas production; a, gas production during incubation; b, potential gas production; a+b, fractional rate of gas production; c) were assessed using an in vitro incubation technique with rumen fluid. There was a significant (P < 0.05) effect of harvest time on all studied nutritive parameters and fermentation characteristics. The early harvest plant samples (after 60 days of planting) gave significantly higher values of IVOMD, ME, CP, BS-N, BS-NPN, MN, MBM and fractional rate of gas production and lower values of CF and cell wall constituents than the late harvest. Crude protein, BS-N, BS-NBN, IVOMD and ME were negatively correlated with CF and cell wall constituents. Metabolisable energy and IVOMD were positively correlated with CP, BS-N and BS-NPN. Cutting treatments significantly affected the CP, CF, BS-N, BS-NPN, NDF, ADF, IVDOM, ME, potential gas production and b values. There was no significant (P > 0.05) effect of added PEG on IVDOM, ME, MN, MBM, fermentation characteristics and gas production over 96 h. The greatest proportion of gas production occurred between 6 and 24 h of incubation. The fractional rate of gas production from 100 mg substrate was higher (0.046 mL/h) for the plant samples harvested at early stage and cut at 30 cm length than harvested at late stage (0.018 mL/h). C values were negatively correlated with lignin concentrations. The amount of MN and MBM produced from 100 mg substrate amounted to 1.29 mg and 14.95 mg at early maturity stage and 0.68 mg and 7.89 mg at late stage, respectively. Microbial nitrogen and MBM production were negatively correlated with CF, cell wall constituents and gas production but positively correlated with CP, BS-N and BS-NPN.

Annual Biomass Production, Chemical Composition and In- sacco Degradability of Different Cultivars of Moringa oleifera

“…The CP content of even Moringa stem of different cultivars was higher than that of Napier or Guinea grass (109.0 g kg -1 DM and 91.7 g kg -1 DM, respectively; [27,28]. The CP contents of Moringa tops reported in this study are within the range of 193.0 to 264.0 g kg -1 DM, reported earlier [25,29,30,31,32,33,34,35]. The CP of Moringa tops containing leaf to stem ratio of 0.53:1 of the present study was 22.4% (Table 3).…”

“…The CP of Moringa tops containing leaf to stem ratio of 0.53:1 of the present study was 22.4% (Table 3). When it was compared with other feed sources ( [32] and AlMashri [25]. However, different stem to leaf ratio of a harvest affected the level of different cell wall components in different cultivars of Moringa.…”

Evaluation of optimum roughage to concentrate ratio in maize stover based complete rations for efficient microbial biomass production using in vitro gas production technique

“…Significantly (p<0.01) highest and lowest gas production was recorded at 30R:70C and 100R:0C, respectively ( Table-3 ). This increase in gas production with increased concentrate proportion in the inoculum, might be due to increase in the nutrient availability from concentrate [ 19 ] or might be due to lowered cell wall and lignin content in the inoculum as reduction in roughage proportion in the inoculum, which negatively affect the microbial attachment to the feed particles [ 20 , 21 ]. Similar to our results, previous researchers [ 22 - 24 ] also observed an increase in gas volume as a proportion of roughage was replaced by concentrate in the complete ration.…”

“…Similar to gas production, IVOMD, TDOM, and ME values were increased linearly as the concentrate proportion increased from 0% to 70% ( Table-3 ). The increased values might be due to gradual reduction in hemicellulose, cellulose, and lignin content in inoculum from 100R:0C to 30R:70C which act as limiting factors to lower the digestibility at excess amount [ 20 , 21 ] or increased nutrient availability to microorganisms from increased proportion of concentrate in the ration [ 19 ]. Similarly, Polyorach et al .…”

In vitro Gas Production, Methane Emission and Rumen Fermentation Characteristics with Increasing Roughage to Concentrate Ratios

“…Others (Reddy et al, 2016) reported that in vitro OMD and TDOM increased linearly with the increase of concentrate proportion in the diet. They attributed such increase to gradual decrease in cellulose and lignin in their diets, which act as a limiting factor to lowering digestibility (Al-Masri, 2009 andKumari et al, 2012). The increase of in-vitro OMD in rations I, II, III and IV containing 100, 80, 60 and 40% concentrate, respectively (Table 3) might be due to the increase of readily available energy and protein contents of these rations which might have improved microbial growth and fermentation (Chatterjee et al, 2006).…”