Effect of level and degradability of rapeseed meal in rations for dairy cows, 2: Diet digestibility, dietary nitrogen partition and urinary purine derivatives excretion

alimentation des animaux amino acids animal feeding aptitud lechera dairy cows degradation digestibilidad digestibility digestible nitrogen excretion grasa de la leche harina de colza lactosa lactose milk fat milk performance milk protein orina purinas purine purines raciones rapeseed meal ration rations tourteau de colza urine vacas lecheras