Influence of Dill (Anethum sowa roxb.) straw powder inclusion on in-vitro gas production and wheat straw fermentation by mixed rumen micro-organism

Abstract

Present experiment assessed the effect of Dill (Anethum sowa roxb.) straw inclusion on the fermentation of wheat straw in in-vitro gas production. Dill straw contained 95.4, 3.1, 74.1, 53.3, 47.5 and 8.5% of OM, CP, NDF, ADF, cellulose and lignin, respectively with 9.95% total phenol and 0.27 g/kg condensed tannins. The metabolizable energy (ME) content was 5.65 MJ/ kg DM. The inclusion of graded levels of Dill straw powder (0, 5, 10, 15, 20 and 25%) significantly improved in-vitro fermentation gas production (P=0.003). Gas production (mmol gas/ g DM) shown a linear increasing trend (P=0.103) with increasing levels of Dill straw. Though gas production increased still fermentation efficiency shown a decline trend (P=0.144). A linear improvement in truly degradable DM and OM (g/ kg; P= <0.001) and ME content (P = 0.003) was with increasing levels of Dill straw. Microbial biomass production, partitioning factor and NDF degradability coefficient were not affected by Dill straw inclusion levels. The gas production (mmol/g DM) increased by 1.54 mmol accounting 10.6 % increase, with an improvement of 41.31 g/kg accounting to 8.9% of truly degradable OM (TDOM) with 25 % Dill straw. The increase in gas production corresponded with improved TDOM resulted in increased ME of substrate by 11.4%. Inclusion of 25% Dill straw powder seems promising to manipulate rumen fermentation favourably upon poor quality feeding.