You can be the difference in A Kitten's life!
The umbilical cord may be wet. These kittens have no fat to regulate warmth or energy. Use a hot water bottle, heating disc or heating pad to warm the kitten. After warming up (which can take a few hours) the kitten needs to eat. If the kitten is lethargic and won't eat you may need to put honey or karo syrup in its mouth. If the kitten does not improve in the next 30 minutes, you need to contact someone from your rescue, an experienced bottle feeder, or seek medical attention. If the kitten has fleas (ONLY AFTER its stable) give it a bath with dawn dish soap (only once). If you have flea prevention that is safe for 0-5 lbs use that right away instead of the bath.
Never feed a cold kitten. Always warm the formula and test it on your wrist to make sure it's not too hot before giving it to the kitten. A kitten has no gag reflex so aspiration is a hazard and important to avoid. Never squirt formula into a kittens mouth. Hold your finger under its chin and you will be able to feel the kitten swallow. Weigh the kitten before feeding and keep a simple log to ensure it is progressing. Use a syringe with a miracle nipple in order to determine if the kitten is eating the appropriate amount for their age. If milk comes out of the kitten's nose or the kitten chokes turn the kitten head down and pat on it's back and side. If sneezing, coughing, fever, or trouble breathing occur, even days later, seek medical attention right away. The kitten could have aspirated which can lead to aspiration pneumonia. This can be fatal.
Kittens should be in the natural position to nurse, on their belly. Some times it helps to have a stuffed animal for them to nuzzle on and prop it's self up. If a kitten is recently born always check the roof of the mouth for a cleft palate (hole in roof of mouth). Older kittens may have a difficult time adjusting to a nipple and formula. Sometimes it takes 8 hours after intake for a kitten to eat. If you do not have a miracle nipple use a syringe, they may nurse from it. You can get these from pharmacies in an emergency. Some kittens are difficult to feed. At times it may be necessary to burrito wrap them to help them feel secure. Kittens often have eye infections or upper respiratory infections, for this seek medical attention. Kittens that can't breathe or smell are not going to eat well.
Warming the bottle or syringe: Personally I have a coffee mug that I warm in the microwave, (I have adjusted the time needed based on mug size, water amount, and microwave) typically I heat a single mug, filled 3/4 full, for one minute and then add the bottle or syringe to the warmed water, let it sit for 5 minutes. Always check the temperature of the formula before feeding the kitten.
Formula is mixed 1 part formula to 2 parts warm water (or as directed by the manufacturer). Be sure to mix well (Blender bottle). Different types of powdered medication can be added to the formula. Consult a veterinarian before giving any medications. Formula type: I personally like Breeders Edge formula but KMR is also a good choice. After the formula is mixed it should remain refrigerated, and then discard after 24 hours. Never use formula that has been left out of the refrigerator more than 30 minutes. In my experience, some off brand formulas may cause diarrhea.
Taking the temperature is important for many reason. If the kitten is too cool, it will not want to nurse. Never feed a cold kitten. You need to make sure the kitten is warm enough. You may also need to check for a fever if the kittens health is in question. This is done rectally, be sure to use a lubricant.
It is your preference if you potty the kitten before or after a meal. My personal choice is before. Rub their genitals with a warm wipe or tissue. This will help them to urinate and defecate. The mother would do this by licking. If a kitten does not have a bowel movement in 2-3 feedings, use a paper towel instead of wipe, massage their belly under their ribs with your thumb or give it a warm bath.
Some kittens may be very dirty and/or covered in fleas when you receive (or find) them. They may also have diarrhea. After they are warm and stable a bath may be needed. For fleas use dawn dish soap. This will not keep fleas off the kitten but it will kill the ones on it. Use water the same temperature as the kitten or slightly warmer. Never get their little face wet. Rinse and towel dry, and use a hair dyer on cool/warm setting. Never over heat the kitten. Make sure their bed is clean, dry and warm before placing them back. If the kitten's bottom or legs are raw from diarrhea use Neosporin or A+D ointment. Never use a zinc product.
Sibling suckling is when one or more kittens nurses on the genital's of other kittens. Sibling suckling is a serious issue. It is damaging to the victim and bad for the suckler. This can result from hunger but it is also a comfort-seeking action. This will eventually stop but the suckler needs to be separated from the other kittens for a while. This can be sad if there are only two kittens but it is very much needed. Sibling suckling can result in serious infections for all the kittens involved.