When we had big Dogs,a mix we made up called "Grind" had flax seeds,Olive oil,vegetables,(what ever was in season),organ meat(heart,kidneys,or liver),run through a food processor,and put in containers kept in the freezer. A couple of scoops mixed in with the dry food,and it was consumed eagerly.
Mmmmm!
When I last lived in the US, I bought my food in bulk from a Morehead, KY, organic food coop, and used flax seed extensively.
In my case, though I bought the flax seeds and sprouted them before putting them through a powerful blender.
It looks like compacted Kitty Litter, needs some coloring added.
I never realised you could bake with flax seeds!