86% of the global livestock feed intake in dry matter consists of feed materials that are not currently edible for humans
But it also makes an important contribution to food security through the provision of high-quality protein and a variety of micronutrients – e.g. vitamin A, vitamin B-12, riboflavin, calcium, iron and zinc – that can be locally difficult to obtain in adequate quantities from plant-source foods alone
https://www.sciencedirect.com/science/article/abs/pii/S2211912416300013