Prediction of Energy Content of Tropical Forages and Tree Leaves Using NRC-2001 (a TDN-based Model) in Ruminants

An experiment was conducted to predict the TDN content of various tropical forages and tree leaves by the equations of NRC (2001) as given by the summative approach and compare it with the estimated values obtained after digestion trials. Twenty four feedstuffs (8 each of cultivated grasses, leguminous forages and fodder tree leaves) were analysed for their proximate principles, detergent fiber components, ADIN, NDIN and the TDN was then calculated. Gliricidia, Andhra Pradesh Bajra Napier-1 (APBN-1) and groundnut haulms were evaluated as sole feed for total tract digestibility of nutrients and nutritive value using four growing male goats. The TDN (%) obtained by the equations of NRC (2001) for gliricidia (55.4), APBN-1 (60.3) and groundnut haulms (53.3) were in conformity with that of TDN obtained by in vivo studies (53.5, 61.8 and 55.4), respectively. It was concluded that the summative approach provides a rapid, inexpensive and accurate means to calculate the energy density (TDN) of tropical forages and tree leaves.