Effect of different sources and levels of nitrogen on in situ degradability of sugarcane tops (Saccharum officinarum) in cattle

The research was carried out in Mexico, the objective was determined the amount of nitrogen (N) needed to maximize the M degradability in steers consuming sugarcane tops (SCT) (Saccharum officinarum). Four Zebu steers fitted with rumen cannulae were allocated in 4 experiments fed SCT as basal forage. The N sources were Taiwan grass (TG) (Pennisetum purpureum) at 0, 10, 20, and 30%; Poultry manure (PM) 0, 10, 20 and 30%; Urea 0, 0.8, 1.6 and 2.4% and high N/energy supplement (HNES) 0.0, 0.5, 1.0 and 1.5 kg fresh matter/animal/d. Ruminal ammonia concentration (NH3) was similar to TG treatments, fractional degradation rate and total intake increase with addition of TG, however, SCT intake decrease. VFA and Microbial nitrogen production (MNP) (g/d) were not affected (P3 concentrations, MNP, fractional degradation rate (P3 VFA concentrations and MNP (P3 concentration forage intake (P3/l. These trials confirmed that SCT are a potential source of forage for cattle, but as sole food were deficient in N, however it is possible to supply this N by 10% PM, 0.8 % urea or 0.5 kg HNES to satisfy the needs of rumen microorganisms for fermentable N in SCT diets.EThOS - Electronic Theses Online ServiceGBUnited Kingdo