Healthy newborn puppies are the picture of contentment, sleeping much of the time and awakening only to eat.
For the first 48 hours, puppies sleep with their heads curled under their chests. While sleeping, they jerk, kick, and sometimes whimper. This is called activated sleep. It is the puppy’s only way to exercise and helps develop muscle tone. A good mother instinctively keeps her nest and puppies clean. By licking the belly and rectum of each puppy, she stimulates the elimination reflex.
Puppies can raise their heads at birth, but are unable to maintain an upright posture. By 5 days of age they can support their body weight with their front legs. Their eyes and ears are open at 10 to 14 days. By 2 weeks of age they should be actively crawling and may be able to stand a bit. At approximately 3 weeks of age, puppies can sit and are walking normally. They can also eat from a bowl.
Puppies are fully oriented to sight and sound by 25 days. The heart of a newborn puppy beats at 160 to 200 beats per minute. The puppy takes 15 to 35 breaths per minute and has an internal temperature ranging from 94°F (34.4°C) to 97°F (36°C). By 2 weeks of age, the normal heart rate is above 200 beats per minute and the respiratory rate 15 to 30 breaths per minute. The temperature gradually increases to 100°F (37.8°C) by 4 weeks of age.
It is best not to disturb newborn puppies (or as little as possible) – at least until they are a few weeks old. Some dams get anxious when their puppies are handled. There is a theory that too much handling interferes with the process by which puppies learn to identify and relate to their mothers and littermates. These interactions are important in establishing normal canine behavior. When these early imprints do not proceed as they should, a puppy could develop problems with shyness or aggression at a later date.
Early neurological stimulation may build up a pup’s resistance to stress – the goal being a dog who handles stress well.
After 6 weeks of age, positive interactions with humans and exposure to new and nonthreatening situations are important for the development of a happy, well-adjusted pet.