The puppy’s nervous development is not complete at birth. He is born deaf, blind, endowed with a very poor sense of smell and a poorly myelinized nervous system, and is therefore unable to quickly convey sensory impulses, and consequently motions. The mother pushes her puppies towards her teats so that they may suckle the colostrum. This first milk is essential for them to be immunized. Besides his nutritive virtues–it has a much higher protein content than milk–it supplies them with 95% of the antibodies necessary for their protection from infections. The mother thus passes on passively her “immunological memory” to her puppies for a period of five to seven weeks, waiting for the moment when they’ll be in turn able to defend themselves actively against infectious aggressions.
Lactation lasts six weeks on average after giving birth, with a maximum peak of production around three weeks of age. During that period, it is important to feed the mother with a highly palatable food whose high energy density will enable her to cover her energy requirements, while not representing too large a volume of food. The quantity of milk produced by a bitch may be estimated by regularly weighing the puppies before and after their feeds. It can thus be estimated that a 32-kg Labrador bitch feeding eight puppies will produce 2.4 times her own weight in milk to raise her litter!
During the following weeks, the declining lacteal production prompts the mother to regurgitate foods so as to supplement the puppies’ feeds as they’re beginning spontaneously to become interested in their mother’s bowl. This period marks the beginning of progressive weaning that will end between the sixth and the eighth week of age with the switch to a growth food. Like any dietary transition, weaning must be a gradual operation which enables switching slowly from the lacteal diet to a diet suited to the growth stage. The puppies’ nutritional requirements at weaning are qualitatively comparable to their mother’s at the end of lactation (i.e. during the period where she builds up again her reserves), what facilitates the breeder’s task considerably. So, he can put at the puppies’ disposal the same food, designed for the mother’s lactation and the puppies’ growth, mixed with lukewarm water or formula milk. Later on, this food formulated to offer perfect coverage of requirements will be less and less rehydrated, so as to be served as such at the end of weaning before switching next to a post-weaning growth food.