Nonetheless, as dismal as the quality of most commercial petfood is, it is worth noting that *most* animals eating it do pretty reasonably ok. This may say as much for the resiliance of animal physiology as for the petfood manufacturers, but, still, it's where the rubber meets the road
And I mean, really. What do dogs not-infrequently eat ON THEIR OWN INITIATIVE? Rotting roadkilled groundhogs, things out of muddy stenchy drainage ditches, childrens' toys, Cheetohs, chicken manure, hoof trimmings, etc.