Neonatal kittens (under four weeks of age) cannot eat solid food (not canned, not dry) and cannot urinate or defecate on their own, so you must bottle-feed them around-the-clock and stimulate their genitals after every feeding so they can eliminate. For example, if you have kittens less than one week old, they will need to be fed and stimulated every three hours. That means you will be caring for them eight times a day — for example, at midnight, 3:00 a.m, 6:00 a.m, etc. If the kittens are unusually small or sickly, they might need to be fed every two hours.
Skipping feedings or overfeeding can cause diarrhea, which results in dehydration, a condition that can be fatal for small kittens (not to mention a hassle for you to clean up after). Diarrhea requires a visit to the veterinarian.
As the kittens age, the number of feedings they need per day goes down. You can start weaning at four weeks of age.
Powdered kitten milk replacement formula is better for kittens than the canned liquid formula. We recommend that you use only powdered kitten milk replacement formula from the start — or as soon as possible — to prevent diarrhea. Two major brands of formula are available: PetAg KMR® Powder and Breeder’s Edge® Foster Care Feline Milk Replacer. Both brands can be purchased at pet food stores, veterinarians’ offices, or online.
Make sure that the powdered formula you are using is fresh by opening the pop-top and smelling it. It should smell slightly sweet, like powdered milk. If it has a sharp smell like bad cooking oil, cheese, or chemicals, it is rancid, and dangerous to give to the kittens. Do not use any type of formula past the expiration date.
Once opened, kitten milk replacement formula (canned or powdered) must be refrigerated promptly and stored in the refrigerator. You cannot keep opened kitten milk replacement formula out of the refrigerator for very long before it spoils. Think of it as fresh milk.