Preheat oven to 350°F. Line a baking sheet with a silicone mat or parchment paper if not using a non-stick one.
In a small bowl, mix together eggs and peanut butter using a whisk or hand mixer.
In a medium bowl, combine flour and oats.
Add the peanut butter and egg mixture to the flour and oat mixture.
Add half of the water.
Using your hands or a large spoon, combine the ingredients. The dough will begin to form. Continue until the dough is well combined and adding more water as needed.
Add the dried blueberries and gently work them into the dough.
Place the dough on a work surface.
Use a rolling pin to roll out the dough to about ¼ to ½-inch thickness, to your preference.
Use a cookie cutter to cut out the dog treats.
Place the cutouts on the baking sheet.
Bake for 20 to 25 minutes.
Transfer the baked treats to a wire rack to cool.