title: Problems in the determination of the trace element requirements of animals.
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D003035:Cobalt / Q000378:metabolism; D003300:Copper / Q000378:metabolism; D004032:Diet; D005243:Feces / Q000032:analysis; D007408:Intestinal Absorption; D008099:Liver / Q000378:metabolism; D009751:Nutritional Requirements; D012756:Sheep; D013552:Swine; D014131:Trace Elements / Q000378:metabolism; D015032:Zinc / Q000378:metabolism
chemical_list: D014131:Trace Elements; D003035:Cobalt; D003300:Copper; D015032:Zinc