Start from what cats evolved to eat and not from what can be made from the leftovers from human food production. (feline-nutrition.org)
If American pets were not fed byproducts of human food production, they would need the equivalent of food for 42 million people. (foodpolitics.com)
After the fly eggs hatch, the larvae feast on waste: leftovers from human food production like juice pulp, and slaughterhouse scraps like pork blood. (discovermagazine.com)