
Hi Annette,
I wrote a long reply to this and my computer did an unmentionable on me, so I'm starting again....
Your bitch should be safe from the risk of reabsorption now - it usually happens early in the pregnancy, when the whelps are very small. It can happen for a number of reasons - overcrowding, genetic conditions etc, because bitches don't often abort. In fact it has only really been since the advent of ultrasound scanning that absorption has been proved, when fewer pups than were actually seen on the scan are born - or even none at all.
From now on you can start replacing some of the carbohydrate of her food with high-quality protein, so that she gets enough nourishment for her and her rapidly-growing whelps without her putting on fat. Soon she will be happier with several small meals rather than one or two larger ones, particularly if she's having a large litter.
Hope this helps. :)