As I understand it per comment from Diamond Pet Foods that it is common practice for manufacturers to sell salvaged pet foods as feed for livestock.
I know that I don't know much about the industry but it just does not sound good. For most pet food, the ingredients are pet grade (below human grade). those pet foods that are salvaged then become foods for livestock that we human would eat. So, do we really eat human grade food?
I know I think too much. It must be the wheat gluten in Chef Boyardee Ravioli that I ate last night.