EWO you mentioned Field Trial dog food and another was Jim Dandy. Back then those local dog food companies used a lot of whole Horse and Cows etc. in the mix. Would just grind up the whole animal. Then mix it all up some way. You could see the hair parts and bone meal in the meat pellet part of the feed.

Dogs seemed to do well on that older feed. Had laetrile in the vitamin mix. Never saw dogs with Cancer back then. Later after the Laetrile was removed. The newer super dupper type dog foods hit the market. Started seeing cancer and many other ailments cropping up. After several years of feeding that Diamond dog food. My older dogs started falling apart.

Today the Vets are treating dogs with Human disease like conditions. Never heard of such way back when. Our main problem was heart worms and fleas. Later the Fire ants showed up. Cheers