Some female dogs can absorb a puppy and it has been said that they can absorb an entire litter. Below are pictures of a pregnant dam confirmed by ultrasound on day 23.
The ultrasound shows three live pups and one that is reabsorbing. The ultrasound didn't come through all that clear but on the bottom left is the reabsorbed pup. It looks like an eye without an eyeball. Reabsorbing a pup, or puppies, is sort of like a human miscarriage. When the fetus dies, the mom miscarries it. However, when there is an entire litter it isn't safe for mom to abort a single dead puppy, so instead if a fetus dies the dam’s body absorbs it.
Courtesy of MistyTrails Havanese
Although this section is based on a whelping of an English Mastiff, it also contains good general whelping information on large-breed dogs. You can find more whelping information in the links above. The links below tell the story of Sassy, an English Mastiff. Sassy has a wonderful temperament. She loves humans and adores children. An all-around mild mannered, wonderful Mastiff, Sassy, however, is not the best mother toward her puppies. She is not rejecting them; she will nurse them when a human places them on her to feed, however she will not clean the pups or pay any attention to them. It is as if they are not her puppies. This litter is getting mom’s milk with major human interaction, manually giving each and every pup what they need. In return, the pups will be super socialized and will make remarkable pets, however the work involved is astounding. It takes one dedicated breeder to keep this situation healthy. Thankfully this litter has just that. Read the links below to get the full story. The pages within include a wealth of information that everyone can appreciate and benefit from.