In Vitro Assessment of Tropical Tree Leaves as Modulators of Rumen Fermentation

Twenty tree leaves, Ficus benghalensis, F. religiosa, F. infectoria, F. glomerata and Moringa oleifera from both North-East Hilly (NEH) region and Upper Gangetic Plains (UGP) of north India and Spondias mangifera wild, Litchi chinensis, Hymenodictyon excelsum, Elaeocarpus floribundus, Dillenia indica, Mangifera indica, Terminalia chebula, T. arjuna, A. nilotica and Averrhoa carambola from Northeast hilly region were evaluated by in vitro gas production system for their potency to inhibit the methane production. The leaves varied widely in their chemical composition with highest crude protein, ether extract and lowest neutral detergent fibre, acid detergent fibre with moderate tannins and saponins contents in M. oleifera leaves, categorizing it as high nutritive value foliage. Total gas production was significantly reduced only by inclusion of L. chinensis leaves. Out of twenty leaves only nine, inhibited (P<0.001) methane production and the per cent reduction in methane was 32.2, 27.7, 23.7, 21.1, 19.3, 18.6, 17.9 17.8 and 17.4 with T. chebula, M. indica, T. arjuna, F. benghalensis, M. oleifera, F. Infectoria (UGP), M. oleifera (UGP), A. Nilotica and F. glomerata, respectively. In vitro true digestibility of feed was lower (P<0.01) with the addition of leaves of L. chinensis, A. nilotica, E. Floribundu, S. mangifera, T. Chebula, F. benghalensis and H. excelsum, whereas, it was significantly improved with M. oleifera leaves as compared to control. There was no effect on volatile fatty acids and NH₃-N production by the inclusion of any of the leaves. Out of 20 leaves tested, the leaves of nine trees have shown potential to inhibit methane production and can be explored further for animal trials.