Orphaned Kittens

Question
I have, for the past 36 hours, been mothering young kittens that were abandoned by their mother when her owner moved from a fire damaged home, leaving the kittens behind to fend for themselves. Other than the care of "normal" cats I have no experiance. I atempted to reach a vet but was unsuccessfull due to the holiday weekend. Upon researching I purchased bottles and replacement formula and am currently feeding the kittens on demand about every four hours. One (of the four) has succesfully learned to lap the formula from a saucer but still nurses a bit before being through. I have to this point fed them in "shifts" allowing them to decide when they have had enough. All seems to be going well and the litter pan is wet with each changing (following each feeding) however I have yet to see a BM. I am using a towel wrapped finger moistened in warm water to emulate there mothers baths after feeding including paying special attenetion to rubbing their little tummys and anal areas. Am I missing something? Should the lack of BMs be worrying me to the maddening point that I am asking strangers questions at 3 am? LOL
HELP!!!!!!!!   

New mommy to four of the cutest kittens you have ever seen,
Brittany Cahill

Answer
Hi Brittany.  Thank you so much for stepping in to save these kittens' lives!!!

Indeed, this can be worrisome.  It's the worst part of hand-raising kittens for me, to be sure.  Many kittens are constipated by the time I get them, because they have gone some time without care from mama and are often dehydrated from lack of nourishment.  And I have a real problem with formula causing constipation.  Several of the kittens I've nursed have had to see the vet for enemas, be fed lubricants, and even have enemas at home.  I usually wean problem kittens very early.  They can start at about 3 weeks if entirely necessary, with a food available from a vet called Hill's a/d, mixed with formula and fed with a syringe.

Usually 48 hours without a bowel movement is when I start to get concerned and schedule a vet appointment.  By the time 72 hours rolls around, you could be dealing with some very constipated kittens.  A vet can tell pretty easily if a kitten's bowels need to be evacuated with an enema.  He can feel how full the bowels are and if the stool is too hard to pass.  If an enema is needed, the vet will generally do that in the office and then send me home with instructions to watch over them carefully and call if they do not begin producing regular bowel movements (preferably every 24 hours, but some kitens go 48 hours).  If they become constipated again, I usually keep the kittens on a lubricant as instructed by the vet, and begin weaning them as early as possible.  If the kittens are lapping formula at this point, they are old enough to begin weaning IF the formula causes chronic constipation.

Just an FYI, it can take up to five minutes of rubbing their genital area to result in a bowel movement.  And I find that holding the kittens on their side while sort of holding their back legs forward with the same hand seems to be the most comfortable for them (if you watch a mother stimulate a bowel movement, this is generally how the kittens are positioned).