We have bred farm animals to be remarkably productive, but the body is a connected system, and what goes into milk or muscle is often borrowed from fertility, immunity and longevity. The cost may show up in the most vulnerable moments of an animal's life: e.g. after birth, at weaning, or in the heat of summer. This seminar shows how understanding metabolism lets us find these imbalances and correct them, so that productive animals are also healthy ones.