Their scream is often louder and more forlorn. In addition, they will often begin to dehydrate. By becoming familiar with the feel of the skin of healthy pup, you will develop a feel for recognizing a dehydrated pup. You can easily feel the ribs and their skin feels like cardboard. It looses its elasticity and becomes stiff.
Dehydration kills pups in a hurry.
They can do downhill and die in 24 hours. Dehydration is often caused from loose stools. If the mother is cleaning her pups, this can be hard to spot. The hair will look slicked down, and stuck together to give a wet look. If you see this you need to step in and help this pup.