Preheat oven to 400 degrees. Line 2 baking sheets with parchment. Combine flour, wheat germ, brewer's yeast, and salt in a large bowl. Place canola oil in a large bowl. Add flour mixture to oil in 3 additions, alternating with 1 cup stock; mix until combined.
Knead dough on a lightly floured surface for 2 minutes (dough will be sticky). Roll out dough to 1/4-inch thickness. Cut out rounds using a 2-inch fluted cutter (bakedeco.com). Transfer to baking sheets. Make an indentation toward the bottom of 1 circle using your thumb, then press dough to make an arch of 4 small circles on top of the thumbprint using the tip of your pinky. Repeat with remaining rounds. Freeze for 15 minutes. Bake for 20 minutes, rotating sheets and lightly brushing with remaining 1/2 cup chicken stock halfway through. Turn oven off, and let stand in oven for 40 minutes.
Dog treats can be stored at room temperature for up to 1 month.