Rinse liver and cut into 1-inch chunks. Put in a 1½- to 2-quart pan with 1 cup water. Bring to a boil on high heat; cover, reduce heat, and simmer gently until liver is no longer pink in center of thickest piece (cut to test), about 5 minutes. Drain liquid into a 1-cup measure; if needed add more water to make 1 cup.
Put liver in a food processor; break in eggs, including shells. Whirl to puree, adding reserved liquid as needed to keep mixture moving; scrape sides of container often. Scrape mixture into a bowl; add remaining cooking liquid, cottage cheese, wheat germ, and 3 cups flour. Stir until evenly moistened.
Scrape dough onto a well-floured laminate counter or large plastic cutting board; knead until dough no longer feels sticky, adding more flour as required.
Shape dough into a ball and set aside. Scrape counter clean and coat lightly with more flour. Set dough on flour, dust ball with flour, then roll out until ½ inch thick. Cut with a floured bone-shaped cookie cutter.
Bake in a 300 degree oven until bones are tinged darker brown and feel firm to touch, about 1 hour. Transfer to racks to cool. (Once cool, bones should be hard when pressed; if not, return to 300 degree oven and bake 10 minutes longer; cool.) To store, package airtight in refrigerator or freezer. Makes about 4½ dozen 3 ½-inch-long bones.