Nutritional Limitations Associated with the Feeding of Tropical Forages

Ruminants fed tropical forages and byproducts rich in sugars and cell wall constituents and low in protein, exhibit poor appetite and only maintenance or low productivity, even after supplementation with nonprotein N and minerals. In such situations, dietary proteins available for digestion in the small intestine (bypass proteins) are required to support adequate feed intake and production. Moreover, even at ad libitum intake, production may be limited by poor roughage characteristics of the basal diet and the availability of energy nutrients. Providing all other constraints have been removed (i.e., provision of soluble N, minerals, et cetera), the growth of ruminants on many tropical feeds can be markedly influenced by supplying a small amount of good roughage together with both bypass protein (which largely stimulates feed intake) and bypass energy, which apparently increases the efficiency of utilization of available energy and amino acids.