According to Worldometer, the human population is 7.8 billion at the end of 2020 and this population is projected to 7 billion in the next 200 years. This massive human growth is followed by a surge in food demands; particularly the need for animal protein sources and more livestock will be required to meet this demand. This tendency has an inverse relation to the land available to grow animal feed because the rise in population escalates the amount of land used for settlements. So, the need of forage for livestock is persistently increasing.
Forage is a plant material includes grass, legumes, and agricultural wastes eaten by grazing livestock and it as a source of fiber for ruminants. Elephant grass and native grasses are the fresh forage that can be stored as silage when its surplus and use when forage is limited. Some alternative source derived from the agriculture waste also served as forage includes rice straw and corn straw.
Crude fiber is the part of animal feed composed of lignin cellulose components that includes complex carbohydrates. These crude fiber and low protein content of agricultural wastes are difficult to digest for livestock and limiting factors for their use as animal feed. An effective technique that can be used to make these wastes usable for animals is fermentation or silage technology. Silage is the most viable technology for animal forage because it is a fresh preservative containing nearly 60% water content. Silage is a feed material preserved by acidification produced by fermentation that can be stored for a long time without significantly reducing the nutrient value of the materials. Among the non-grain grasses, the elephant grass (Pennisetum purpureum) stands out as forage with excellent potential for dry matter production. This grass is extensively used in silage production having a high amount of soluble carbohydrates.
Available literature confirms the longtime stability of nutrient value in silage. Hidayat (2014) found that 28 days old silage did not decrease or increase the physical appearance of king grass silage. Despal et al. (2011) informed that carbohydrate absorbability is measured by the absorption surface area and the presence of coatings such as fats and fibers, which can decrease the water absorption of materials. Pakistan Journal of Nutrition presented novel research in order to investigate the nutritional and physical characteristics and in vitro digestibility of silage from different sources of fiber. The researchers claimed that the Silage with corn straw as the fiber source tends to provide the best results in terms of physical and nutritional characteristics and in vitro digestibility.