More than 5 million new puppies are born in the United States every year, and many of these dogs will have multiple litters of their own puppies.
Puppies grow a lot during their first few weeks of life. In fact, to promote growth, a newborn puppy spends 90% of its first week sleeping and 10% of its first week eating.
Another reason for spaying or neutering: a male and female dog and their puppies could potentially produce more than 66,000 dogs over the course of six years. That equals 11,000 dogs per year or well over 900 per month.
Unlike humans, who carry babies for 40 weeks, female dogs carry their young for only 60 days. The puppies develop rapidly inside the mother during this time.
Puppies develop their permanent teeth more quickly than human children do, as their teeth are important to their survival. Puppies generally have a mouth full of them between 4 and 6 months of age.
When puppies are born, they are deaf, blind, and toothless. Therefore, they depend on their mother to care for them. Additionally, puppies do not develop their sense of smell until three weeks of age.