Biomass Yield, Chemical Composition, In-Vitro Organic Matter Digestibility and Gas Production of Morphological Fractions of Mulberry ( Morus alba ) Plant Harvested at three Cutting Stages

摘要

Bio-mass yield (BMY), chemical composition, in-vitro organic matter digestibility(IVOMD) and gasproduction (GP), metabolizable energy (ME), methane and short chain fatty acid (SCFA) productions ofMulberry (Morus alba.) plant fractions (leaf, stem edible branch and whole plant) harvested at three cuttingstages were evaluated. The plants were harvested at 6,8 and 10 months after planting which was denoted asstage 1,2 and 3 respectively. Among morphological fractions the highest (p<0.05) dry matter yield was for stemwhile the lowest (p<0.05) was for edible branch. The DM yield increased (p<0.001) with increasing stage ofmaturity for all fractions. The CP content decreased (p<0.001) with increasing stage of maturity for leaf andedible branch. The neutral detergent fiber (NDF) content for stage 1 and 2 was lower than stage 3 for leaf, ediblebranch and whole plant. The acid detergent fiber (ADF) for stage 1 in leaf was lower than that of stage 2 and3. The IVOMD of leaf and whole plant was similar for stage 1 and 2 which was significantly higher than the thirdcutting stage. For edible branch and stem IVOMD decreased (p<0.001) with increasing stage of maturity. Thehighest (p<0.05) gas production was from leaf while the lowest was for stem. Gas production from immediatelysoluble fraction (a) showed lower and negative value among plant fraction except whole plant. Gas productionfrom insoluble but degradable fraction and the potential gas production (a+b) was highest (p<0.05) for ediblebranch while the lowest (p<0.05) was for stem. The IVOMD, ME and SCFA decreased (p<0.05) with increasingstage of maturity. Methane production from leaf decreased with increasing stage of maturity at 24 hours ofincubation. The highest amount of methane production was from leaf and whole plant at first and second stageof cutting. High CP and IVOMD and low fiber content for Mulberry leaf indicate that it could serve as proteinsupplement and the other fractions of mulberry is also use as alternative feed resources for low quality forages.First cutting stage is recommended as the right stage to obtain optimum protein content and digestibility. Onthe other hand to obtain optimum bio-mass yield, the third cutting stage is a good stage for harvesting. Furtherfeeding trial is recommended by authors to verify the quality of the leaf on local Arsi-Bale sheep breed.