Low-input grassland use and pasture management

agriculture extensive aptitud lechera azote conduite des herbages conservation de la nature contenido proteico cycling dairy cows digestibilidad digestibility energy value extensive farming forraje verde fourrage vert gain de poids ganancia de peso grassland management grasslands grazing systems green feed heifers herbage manejo de praderas milk performance nature conservation nitrogen novilla nutritive value pollution by agriculture pollution par l'agriculture praderas protein content sistemas de pastoreo vacas lecheras valeur nutritive valor nutritivo weight gain