Environment and reproductive performance in Norwegian dairy cows. Studies of reproduction management, artificial lighting, and nutrition.

artificial light atalaje attache basal metabolism body conformation cetose cetosis ciclo estral composition globale conformation animale control ambiental cycle oestral dairy cows energy balance environmental control fertilization fotoperiodismo hatos herds ketosis livestock management luz artificial manejo del ganado metabolismo basal milk yield noruega norway oestrous cycle performance de reproduction photoperiodicity progesterona progesterone proximate composition rendement laitier rendimiento lechero reproductive performance reproductividad tethers troupeau vacas lecheras