Biological additives improved qualities, in vitro gas production kinetics, digestibility, and rumen fermentation characteristics of different varieties of rice straw silage

Context. The amelioration of low-quality cheap feed for livestock production has become a huge challenge faced by the livestock producers coupled with the illicit disposal of the straw, which causes global environmental nuisance through burning and health impairment. Aims. The purpose of this study is to examine the efficacy of biological additives on nutrient profiles, silage quality, in vitro rumen fermentation in different varieties of rice straw silage; ML4, ML10, ML21, ML24, MR219 and Putra-1 were ensiled with water (control), enzyme (E) and a combination of bacteria and enzyme (BE) in a complete randomised design (CRD) experiment. Methodology. The rice straw varieties, obtained from the paddy research farm were chopped to similar to 2-3 cm, treated according to the above treatments to attain 70% moisture content and compressed in a 1 L jar and ensiled for 30 days. Key results. Crude protein (CP) in the treated rice straw silage was higher than in the control. The treatment with BE had a lower neutral detergent fibre (42.31%) and a lower acid detergent fibre (21.08%) concentration for Putra-1 than did other treatments (E and control) and varieties. For the silage extract, the lowest pH, NH3, butyric acid and propionic acid were obtained in the BE treatment in most of the rice straw varieties. In addition, straw treated with BE had the highest lactic acid content, in vitro gas production kinetics, digestibility, and rumen fermentation, compared with the E and control treatments. Conclusion. This study showed that a BE treatment effectively improved the quality of rice straw silage, with the Putra-1 variety giving the most outstanding result.