Effect of Condensed Tannins Supplementation from Tanniferous Tree leaves on In vitro Nitrogen and Substrate Degradation

This study was carried out to assess the effect of strategic use of condensed tannins (CT) from tanniferous tree leaves on the in vitro nitrogen and substrate degradation. Tanniferous tree leaves of Psidium guajava, Ficus bengalensis, and Ficus infectoria were selected as a potential CT sources and used at graded levels (0, 1.0, 2.0 and 3.0%) to protect the nitrogen degradation of mustard oil cake (MOC). Supplementation of CT @ 1–3 percent significantly (P<0.01) reduced the in vitro nitrogen degradation (0.87–0.51) irrespective of CT sources, however, nitrogen protection in the rumen was highest (P<0.01) at 3.0 percent CT inclusion followed by 2 and 1 percent CT levels. CT inclusion from all the three tropical tree leaves exerted similar effect on in vitro nitrogen degradability of MOC and reduced 39% in vitro nitrogen degradation of MOC. Gas volume produced in 24 h (ml/200 mg) and partioning factor were reduced significantly (P<0.01) with CT supplementation from 1 to 3% levels, though, efficiency of microbial-biomass production increased significantly (P<0.01). Truly degradable organic matter in rumen did not differ significantly (P>0.05) up to 2% CT inclusion. It may be concluded that condensed tannins from tanniferous tree leaves can be used effectively to protect the nitrogen degradation of mustard cake without any adverse effect on substrate degradation.