The role of livestock on the land is that of a tool (Salatin quote). Their job is to efficiently harvest available forage, turn it into a healthful protein, and then finish the nutrient cycle to reduce and eventually eliminate the need for outsourced fertilizers. Without livestock this cycle is broken and the natural balance is upset. Nothing has so profound an impact on the fertility and vitality of land than properly managed livestock.
The role of livestock and our health is one of nourishment; both mentally and physically. They convert the abundance of the land into a wholesome, nutrient-dense protein that nourishes our bodies. Their presence on the land is a source of pleasure and enjoyment for any observer. They bring life and completeness to a landscape.