Improving the nutritive value of rice straw by ensiling with different additives

Ensiling effect on post harvest rice straw using conventional and unconventional additives was investigated. The emphasis was on nutrient content and nutrient digestibility. Field cured rice straw was ensiled with combinations of molasses, urea, cassava starch and caged poultry dropping. The fermentation was done in an ensiling pit measuring 2.44m x 1.22m, lined with polythene sheets and lasted 20 days, the fermented samples of rice straw and the hay were analyzed. In a 5 x 5 latin square experiment, 5 male West African dwarf goats were involved in a digestibility study of the rice straw silages. The control was the hay of rice straw. The digestibilities of the nutrients were estimated. The dry matter, organic matter and, lignin reduced and crude protein, ash, nitrogen free extracts, hemicellulose and cellulose increased. The silage with additives of poultry dropping had high ash contents. The molasses and urea combination affected higher contents of organic matter, neutral detergent fibre and lignin. The silages had pH<6 and temperature of (<degrees>C) 36.7-41.2. Molasses and urea combination was poor in the digestibility estimate of ether extract. All the silages exhibited reduced digestibilities of crude protein in the order of molasses and urea> starch and urea> molasses and poultry manure>starch and poultry manure. Compared with the control, the starch and poultry manure combination was poor in the digestibility of all the nutrients. The 3 other combinations improved the digestibilities of dry matter, crude fibre and organic matter and ether extract. Starch and poultry manure would do well as fermentation additives only in combination with molasses and urea. The combination of starch and poultry manure did not prove suitable and may require a low level of protein supplementation.