Nutritive value of morphological fractions of Sesbania sesban and Desmodium intortum

Abstract

Nutritive value of morphological fractions of Sesbania sesban [15019] and Desmodium intortum was determined based on their chemical composition, in sacco dry matter (DM) degradability, in vitro gas production and in vitro organic matter digestibility (IVOMD). In sesbania, neutral detergent fiber (NDFom) and acid detergent fiber (ADFom) contents were higher in twigs and green pods (P<0.05) than in whole forage and leaves, whereas the acid detergent lignin (ADLsa) content showed the following ranking order (P<0.05): green pods > twigs > whole forage > leaves. The soluble tannins (STs) content was higher (P<0.05) in green pods and leaves than in twigs whereas the content of condensed tannins (CTs) was higher (P<0.05) in leaves and whole forage than in the twigs and green pods. All fractions had sufficient levels of macro and micro minerals, except sodium. Sesbania leaves and whole forage had higher (P<0.05) potential degradability (A+B) and IVOMD values than other fractions. In sacco DM degradability ranked sesbania fractions in the following decreasing order: leaves ≥ whole forage > twigs > green pods.
In the case of desmodium, the twigs had lower CP contents and leaves had lower NDFom, ADFom and ADLsa contents than the other fractions. The STs concentration was highest in leaves and lowest in green pods whereas the CTs concentration was higher in whole forage than in twigs. The washing loss (A) was higher in twigs than the other fractions, while the slowly degradable fraction (B) was higher in green pods than in twigs. In the view of the optimal nutrient contents, supplementation with whole or fractionated forage parts of both sesbania and desmodium can improve the nutritional status of ruminants fed low quality roughages.