Homemade kitten milk replacer, or formula, is essential for kittens that won't suck, or when there is no lactating mother cat available for the kitten. Kitten supplement formula—sometimes referred to as "kitty glop" among breeders, or as "cat milk substitute"—is often used with orphaned kittens but can also be used with hungry newborn kittens.

Under normal circumstances, kittens are cared for and fed by their mothers. Their mother's milk provides them with all the nutrition they need for the first month of their lives, but difficulties may arise that make a mother cat's milk unavailable.

Here's how to make kitten milk replacer and give it to a kitten.

How Do You Make Your Own Kitten Formula?

A variety of recipes for homemade kitten formula exist, but if you can purchase a kitten milk replacement from the pet store to use, that is ideal. For times when store-bought milk replacement is not an option, find a recipe for which you have all the ingredients, until you can get some milk replacement formula. 

A homemade kitten replacement formula should not be used beyond 24 hours (as long as it is out of the refrigerator).

The following formulas are from The Cornell Book of Cats by the Cornell School of Veterinary Medicine:

Kitten Replacement Formula #1

• 1 quart whole goat’s milk
• 1 teaspoon light Karo syrup
• 1 tablespoon nonfat plain yogurt (made with goat’s milk preferably)
• 1 egg yolk
• Unflavored gelatin
• Newborn to 1 week — 1 package gelatin
• 2nd week — 1-1/2 to 2 packages gelatin
• 3rd week — 2-1/2 to 3 packages gelatin
• 4th week — 4 packages gelatin

Put the goat’s milk in a saucepan and add the proper amount of gelatin based on the kitten's age. Heat the mixture just until the gelatin is dissolved and then remove it from the heat. Mix in the remaining ingredients and refrigerate. It will keep up to one week in the refrigerator.

Kitten Replacement Formula #2

• 8 ounces homogenized whole milk
• 2 egg yolks
• 1 teaspoon salad oil
• 1 drop liquid pediatric vitamins (optional)

Mix well and keep refrigerated.

Kitten Replacement Formula #3

• 1 part boiled water to 5 parts evaporated milk
• 1/2 teaspoon bone meal per 16 ounces fluid

Mix well and keep refrigerated.

Kitten Replacement Formula #4

• 1 can evaporated milk
• 1 egg yolk
• 2 tablespoons corn syrup
• 1 drop liquid human pediatric vitamins (optional)

Mix the milk, egg yolk, and syrup well and store it in a tightly sealed jar in the refrigerator. At feeding time, mix half of the estimated feeding amount with an equal amount of boiling water. Once a day, mix one drop of the human infant liquid vitamins in each kitten's formula portion. 

How Do You Feed a Newborn Kitten?

If you need to bottle feed a kitten, you'll need to use special baby bottles. Tiny baby bottles with tiny nipples for kittens can be purchased online or in pet stores. These bottles typically hold small amounts of formula, so they are easy to handle while also holding a small kitten.

If you can't find a tiny baby bottle, you can also try using a syringe without the needle, especially if the kitten won't take the bottle readily. Oral syringes can usually be purchased from a pharmacy and used for this purpose.

Heat your homemade or store-bought formula until it is warm, and test a few drops of milk on your wrist first. It should feel just a little warm or even cool, not too warm or hot. It is not recommended to use a microwave.

Most people put the formula in the bottle or syringe and then place the bottle or syringe into a bowl of hot water to heat it up. Once the formula passes the skin temperature test, you are ready to feed the kitten.

Keep the kitten in a natural feeding position on their belly and offer warm formula every three to four hours until the kitten begins to wean to solid food.

Kittens should eat about 8 mL of formula per ounce of body weight a day. This means that if the kitten weighs 4 ounces, they should eat about 32 mL of formula in total within a day, so you can give 8 mL of formula every 4 hours.

If constipation occurs, add one drop of vegetable oil to each kitten's formula, no more than once daily, until the problem is resolved.