6 week old runt kitten

Question
I have a 6 week old runt kitten. She is 5.1 ounces, as of yesterday. She has 4 other litter mate, 2 males and 2 other females. She has always been the smallest one. She isn't having trouble nursing, but her mother is more interested now in weaning her and her siblings. We have been bottle feeding her for the last week, with the KMR, but I feel that the kitten nipple is too large for her. Her temperature has been low. We have been using a heat lamp, a hot towel in a bag wrapped in another towel, and a stuffed animal to keep her warm. Any ideas on how to feed her the proper amount? Any ideas on how to keep her warm without the aid of us always with her? Her other siblings are thriving very well and are actually quite large.

Answer
Hi Lindsey.  To keep my little ones warm, I keep them in a large cat carrier with a heating pad, set on low setting, with a thick towel over the heating pad.  There is an area in the carrier large enough for the kittens to move off of the heating pad if they feel too warm.  

If you feel the nipple of the bottle is too large, I have a feeling you may have a Pet Ag bottle?  This is the brand name, the same company that makes KMR.  Most kittens will eventually adjust, but I do feel the tips of these nipples are a little on the large side.  If you do have a Pet Ag bottle, you may have better luck with a Four Paws bottle.  The nipples are tapered.  You can find them in a lot of pet stores, or if not, online (amazon.com for one).  Typically, my kittens of this weight will be eating between 20 and 30 cc's (ml's) every four hours.  

The normal body temperature of newborn kittens is a couple degrees below that of adult cats because of their tiny size and lack of fat, which holds in body heat.  Your little one is about the size of a two-week-old kitten, so I'm not entirely surprised that her temperature is still low.  But if she hasn't seen a vet, I would get her in for an exam.  A low body temperature will also make them more susceptible to infection, and if she's happened to pick anything up, this could be a reason why she's been so slow to put on weight.  If anything seems amiss, an antibiotic might be warranted, or one may even be given to protect her, just in case.