Before use make a hole in the nipple using one of the following methods: Cross cut nipple with a razor blade. Using a strong needle or cuticle scissors, enter and exit the tip of the nipple as though you were making a very small stich or snip, pull the needle out removing a small piece of the nipple. Check flow with water. A steady drip or thin stream should be achieved when a slight pressure is applied to the nipple. If one or more of the animals is ill use a different bottle or feed ill animal last. Wash bottle, cap and nipple with hot soapy water and rinse thoroughly after each feeding session. If animal is too small or weak to nurse, consult your veterinarian.