Urea and crude glycerin as additive in sugar cane silage

The aim of this study was to evaluate the inclusion of urea and crude glycerin as an additive in ensiling of sugar cane, in chemical composition, pH, ammonia-N (N-NH3) and in vitro digestibility (IVD). The treatments were four doses of urea 0, 10, 20 and 30 g per kg of sugar cane ensiling and five doses of crude glycerin 0, 10, 20, 30 and 40g per kg of crude glycerin sugar cane ensiling. The silages were stored for 180 days. Treatment with urea affected most variables related to nutritional value, increasing the concentrations of dry matter (DM) and protein (CP) (2.58, 7.76, 18.70 and 19.31%) and reduced levels of neutral detergent fiber (NDF) and improved IVDDM (42.61, 48.53, 50.69 and 51.18%) and NDF (38.81, 39.23, 41.06 and 43.46%) and fermentation characteristics of silage, with pH values of 3.49, 3.86, 4.18 and 3.93 and NH3 1.72, 3.80, 7.88 and 9.00 for the dose of 0, 10, 20 and 30 g, respectively. The crude glycerin increased in DM and ether extract (1.45, 3.03, 3.62, 3.41 and 4.38%), improved IVDDM with values of 49.61, 52.24, 53 28; 55.60 and 56.09% and reduced gas losses during the fermentation process with mean of 6.69, 5.97, 5.89, 5.51 and 5.48% of DM for the doses 0, 10, 20, 30 and 40g, respectively. Urea and crude glycerin can be used as an additive in ensiling of sugar cane.