Partitioning of nutrient and trace elements in feed among milk, faeces and urine by lactating dairy cows

agua potable cow milk dairy cows drinking water eau potable ensilado ensilage (produit) excretion faeces feces foin hay heces heno lait de vache leche de vaca nutrientes nutrients nutrition physiology orina physiologie de la nutrition silage substance nutritive urine vacas lecheras