How Puppies Develop
Puppies are born about two months after conception – 58 to 63 days on average – and are quite helpless little beings that do not look much like a dog. Because the gestation period is so short, many of their critical organs, including the brain, are not fully formed and need more time to develop. That is why puppies are born functionally blind (their eyelids are tightly closed) and deaf (their ear canals are closed).
In the wild, the mommy dog has to look after her helpless pups but must also survive by hunting. Nature solved this problem by making it possible for them, while in that very vulnerable condition, to remain quietly and safely stored in the den while mom is away. During the first two weeks they sleep nearly 90 percent of time.
Between hunts she is able to care for her toothless little babies that are unable to regulate body temperature, urinate or defecate on their own. Puppies depend on their mother and littermates for warmth and can quickly die from the cold. Cold, lonely puppies cry to alert Mom of the problem.
Puppies first experience the sensation of being petted when washed by the mother’s tongue. She does this to stimulate them in order to defecate and urinate as well as to keep the nest clean. The first milk the mother produces is rich in antibodies that help protect them from disease. They exercise by crawling over each other and their mother.
The closely shut eyes protect their immature optical system from foreign objects such as dirt or grit and possibly also from bright light that may cause damage. Most puppies begin to open their eyes after about two weeks of age. It will take several more weeks before their eyesight begins to approach normal.
Dogs are not colour blind but see things in various shades of blue and yellow apart from black, white and grey. Purple and blue are both seen as shades of blue. Orange, yellow and green are seen as shades of yellow as is the grass. If you want to give your puppy a toy to play with on the lawn then you should choose blue toys.
The ear canals begin to open about the same time as the eyes open. Silence is important for the developing ears. If a pup’s ears are forced to respond to sound before its auditory system is fully developed it could cause great damage to his hearing as an adult.
Within a week or so the puppy’s hearing will be fully useable and quite acute. They can hear about 4 times the distance of normal human hearing. That is why they are at the gate waiting because they heard your car coming when it was still far away. They can hear other dogs announce the arrival of the postman when he is still three blocks away. Puppies can also hear higher pitched sounds that we cannot hear. Dogs have 18 or more muscles in their ears making it possible to turn them in the direction of the sound for better hearing.
We do not always realise that dogs sense the world in a very different way than we do. Dogs use their noses in a similar way we use our eyes. They literally “see” with it. Things are not what they look like to dogs until they get to smell it first. That is also the reason why a blind or deaf dog can get along fine under certain circumstances. Humans have about 5 million olfactory or scent detecting receptors. Dogs on the other hand have between 125 million to 300 million (depending on the breed). “To our dogs we are our scent.” says Alexandra Horowitz. Perhaps stinky but it is your ID for your dog.
During the period when puppies cannot see and hear, which is until they are about 21 days old, they rely solely on scent to interpret their world. They are able to use their sense of smell and touch to find their way about the nest and to get to their mother’s scent-marked nipples. Puppies have heat sensors in their noses to help find their mother during the time their eyes and ears are closed. These sensors disappear by the time they reach adulthood.
Dog’s noses are wet. The mucus on it captures scent particles and actually helps it smell. They can move their nostrils independently so they can tell from which direction a smell is coming. Dogs can both sniff and breathe. Breathing is for air, but when they sniff they retain some scent that does not get exhaled.
New-borns aren’t able to support their weight and crawl about with the movement of their front legs. They are usually able to stand by day 15 and take their first steps by day 21. Their rapid physical and sensory growth enables them to move from total dependence on Mom to begin to play with their littermates and explore their environment. Baby teeth begin to appear and are all in place by about five or six weeks. They can now begin to sample other foods as they move about.
From the third week of life onwards puppies enters their socialising period. It is during this time that interactions with other puppies are formed that will be remembered for life. During this time and particularly at age six to eight weeks old, puppies learn to accept others as part of the family. Some are active, bossy and strong and others are withdrawn and shy.
Around four weeks of age the mother’s milk production begins to slow down just as their energy needs increase. The mother slowly begins to wean her babies and they begin to sample solid foods. Weaning should be complete by week eight.
As their physical world changes and they find themselves exploring objects with curiosity they also now begin to react with fearfulness. This is a normal part of development and the pup learns to be more cautious. Their brains are not fully programmed and anything that really frightens them may have a lasting effect. The breeder has a very important job to supervise and counter fear reaction.
Older is better
Once they are eating well on their own puppies may be placed in new homes. However, the longer they stay with Mom and interact with their littermates the better their adjustment and the better pets they tend to become. They still need to learn to become a dog, to react to canine communication and find their place in doggy society. While playing in the litter they begin to learn bite inhibition when their siblings yelp when a bite hurts. Eight weeks old puppies tend to make the adjustment to their new homes better.
Dogs communicate by smelling, seeing and lastly hearing. So in our training we should also follow a nose, eyes and then ears approach.