But if it's too small, they won't be able to drink it. Once you've made the hole, test it yourself. When you're satisfied with the flow rate, you can feed the babies. Slowly pull up and forward on the bottle so that he will nurse with his head extended and slightly elevated. Make sure that the neck of the bottle remains filled with milk so the kitten isn't sucking air.
Formula spewing out of the kitten's nose means the hole is too big.
If this happens, hold the kitten upside down until he stops coughing. Most kittens have an automatic cut-off valve, and the nipple will usually pop right out of their mouth when they are full. However, as a guide, feed each kitten two tablespoons of formula daily for every four ounces of weight. Very small kittens should eat every four hours. Like human babies, they will let you know when they are hungry.