1. AOAC (1998) Official Methods of Analysis, Association Official Analysis Chemical, 16th ed., Washington, DC.
2. Colombo, D., Crovetto, G. M., Colombini, S., Galassi, G., and Rapetti, L. (2007) Nutritive value of different hybrids of sorghum forage determined in vitro. I. J. Anim. Sci., 6, 289-291.
3. FAO Database (2003).
4. Harfoot, C. G. and Hazlewood, G. P. (1997) The Rumen Microbial Ecosystem, Chapman & Hall, London.
5. Hungate, R. E. (1966) The Rumen and Its Microbes, Blackie Academic and Professional Press, London, pp. 8-90.