This pic does not say if it's talking about the total or the total per unit consumed, nor does it give a measure of what the total is. The chart is unfortunately not especially helpful in a vacuum. Which is not to say you're interpreting it wrong, I just cannot tell if your conclusion there is actually valid. Or if it's post-consumer (i.e. table scraps) or industrial (i.e. animal feed that goes bad) which dramatically changes the interpretation if animal production and cereal grain waste are correlated.

This doesn't really make sense, though. You have to grow grain in order to raise livestock. Without seeing how these numbers were calculated, it's hard to say exactly what this graph is showing.