
They cant regulate their heat for three weeks at which point their temperature finally reaches adult levels.
http://motherandpuppies.royalcanin.co.uk/from-nursing-to-weaning/week-by-week-from-birth-to-weaning"Don't forget, the puppy is incapable of regulating his own temperature!
Hence, the importance of ensuring that the whelping area is placed in a warm room.
A temperature of at least 30° C within the environment of the puppies is necessary during the first week.
The easiest way of checking the temperature is to place a thermometer in the whelping box.
Temperature can then be progressively brought down to 25° C during the fourth week. "
Mine is a thick coated Nordic breed (even the newborns have thick coats) and I never keep it that warm, but they do have an den like whelping area.