If you happened to see kittens without their mother, identify if they are truly being abandoned. Read tips here on how to identify them.

If the kittens are indeed being abandoned, and you are not prepared to take on the responsibilities of motherhood, feel free to call your local rescues. You may be instructed to bring the kittens to the nearest vet to be inspected, the vet will also able to help you decide on their current condition & needs.

If the kittens are only about a few weeks old (less then a month) they may not be able to eat soft of solid food and will need to be bottled fed.
Fosterers for bottle babies (kittens without mommas that cannot eat solid food yet) are always in short supply because they are a lot of work.
But even if the rescuers or fosterers can’t take in your litter they may have tips and tricks to make your go at being a momma cat much easier.

First Steps

  1. If you feel you must take the kittens in, wrap the carrier or container you will transport them in in a towel for warmth, but make sure you leave air holes uncovered so the kittens won’t suffocate.

  2. Check to see if the kittens are warm. This is more important than feeding. You can tell a kitten is cold if the pads of his feet and/or ears feel cool or cold. Put your finger in the kitten’s mouth. If it feels cold, then the kitten’s temperature is too low. This is life-threatening and must be dealt with immediately. Warm up the kitten slowly over 20 minutes by wrapping him in a towel or baby blanket, holding him close to your body, and continually rubbing him with your warm hands.

  3. Determine the age of the kittens by bringing them to the vet or comparing them to the photos and descriptions on the How Old Is That Kitten? Kitten Progression: At-a-Glance page on the Alley Cat Allies website.

  4. If the kitten need to be bottle fed, prepare for bottle-feeding, kitten replacement milk (KRM), nesting box, towels, heating pad or hot water bottle.

              

Caring for newborn kittens requires patience and diligence. Here’s some tips on how to take care of bottle babies.

  1. During the first few weeks of life, a kitten’s primary concerns are feeding, keeping warm, developing social skills and learning how to excrete on his own.  Do not offer regular cow’s milk to cats of any age. It is not easily digestible and can cause diarrhea.

  2. It is essential that you keep the young one warm. A heating pad or a hot water bottle wrapped in a towel works well. The heat source should be positioned so that the kitten can move away from it at will.How to prepare the feeding bottle: The nipples are usually unpierced. With a sterile pair of scissors, make a small slit. Start very small and enlarge as necessary. To avoid choking the kitten, fluid should freely dribble from the nipple only when you apply pressure on the bottle. The milk replacement is sometimes called “kitten milk replacement” or simply “kitten formula.”

  3. Newborn kittens may nurse about every 1-2 hours. Make sure the milk are warm before feeding the kitten. You may test the warmth level on hand first. Never feed a cold kitten! If the kittens are cold, you will need to warm them up slowly. At about three to four weeks old, they can be offered milk replacer from a bowl and then small amounts of moistened kitten food four to six times a day.How to feed: Position the kitten on his belly on a soft surface, such as a towel or blanket, in the palm of your hand or on your inner forearm, facing away from you. If the kitten cannot hold up his head on his own, gently cradle the head in your fingers. Place the nipple of the bottle to the kitten’s mouth and tilt it slightly so that the milk replacement fills the nipple. The kitten should automatically start sucking on the nipple. If he doesn’t, gently tease the nipple back and forth to encourage him to latch on: A reluctant kitten will often grab the nipple as it’s retreating. After the kitten has had enough, burp him gently.

  4. After feeding, a mother cat will groom her babies, paying special attention to the anal area. This stimulates excretion, which kittens can’t do on their own until their second or third week. If your kitten is no longer with her mother, dip a soft washcloth or a piece of gauze in warm water and gently massage the anal and urinary regions. The warmth, texture and movement mimic a mother cat’s tongue. When the kittens are four weeks old, you can teach them to use a litter box by placing them in the box after their meals. Cutting one side down will make it easier for the kittens to go in and out.

Start the weaning process at approximately 4 weeks old. Place milk replacement in a flat saucer or dinner plate and place your finger in it and touch it to the kittens’ noses. Once they are intrigued by the taste or smell on your finger, let them follow your finger to the saucer.

Mix canned kitten food into the milk replacement a few days after the kittens begin lapping the formula on their own. Allow the kitten food to become thoroughly soggy before feeding.

Decrease the milk replacement in the canned kitten food mixture daily until the kittens eagerly and readily accept the canned kitten food.

Reference and source:
https://pets.webmd.com/cats/guide/newborn-kitten-care#2
https://pets.thenest.com/care-premature-newborn-kittens-4811.html

What to Do (and NOT Do) If You Find a Newborn Kitten