Erin Katribe, DVM, MS, Medical Director at Best Friends Animal Society, told Bored Panda that prior to weaning (when puppies transition from milk to solid food), the little rascals obtain all of their nutrition from their mother's milk. "Weaning naturally begins around 4-6 weeks of age when puppies begin to show interest in food," Dr. Katribe said. "This early, however, they should still have access to their mom to be able to nurse as their transition to solid food is gradual."

The weaning process is very important to pups; they learn behaviors from both their mother and littermates. The important benchmarks needed for puppies' separate life should be met in a naturally progressing order. Otherwise, problems can arise as the puppies mature into adulthood.

"The social interaction of the mother with puppies is critical until at least 7 weeks of age, and ideally longer. They learn how to interact with one another – how to 'speak' dog," Dr. Katribe said.

"For example, through biting and mouthing during play, mom and littermates will signal to a puppy when things get too rough and will end the play – this is how a puppy learns bite inhibition, that mouthing or biting too hard is not OK. This is an important skill for later in life. Puppies also learn about different body postures and types of vocalization, key components of canine communication."

Katribe stressed that puppies should remain with their birth family until at least 7 weeks of age to gain the full psychological development they can reach through interaction with their mom and siblings. "The ones that are separated from their mother and litter earlier are more prone to behavior disorders, including separation anxiety and increased fear responses," the doctor explained. "Puppies that remain with their mother and litter longer, particularly if they're being exposed to new experiences, tend to respond better to novel experiences later in life and become better-adjusted pets."

On the other hand, puppies that are bred specifically to purchase at pet stores, for example, are separated very young and then housed only in a kennel with limited exposure to new sights, sounds, and experiences, and so their socialization suffers.

"In the shelter setting, if moms and puppies are physically housed at the shelter, we have to balance the benefits of keeping them together with the risks of infectious disease that are higher in that setting; ideally, mothers and litters are housed in foster homes, and not on-site, as this reduces disease risk and provides a much better environment for important socialization for the puppies through exposure to new experiences and to people," Katribe explained.

"If moms and puppies must be housed on-site at the shelter, starting the weaning process and separating puppies from mom earlier will allow them to be adopted earlier; then they can experience socialization in their adoptive home. Even when puppies are housed in foster homes, sometimes it makes sense to wean and separate toward the earlier end of the ideal range – if we move them through faster to adoption, then that foster home is now available to save the lives of other mothers and puppies, dogs that might not have a chance without that foster home."

As cute as these pictures look and as rewarding as it is, we need to remember that caring for puppies or moms and litters is a lot of work. "Fostering a mom and puppies or fostering an older puppy (until it is old enough for spay/neuter and adoption) for your local shelter can be a great way to get a small taste of what that’s like, without making a longer commitment," Katribe highlighted. 

"Fostering also saves lives for shelters that are otherwise stretched for housing space or resources."

Plus, sometimes we can't control when a puppy is separated. Just think of all the orphans out there. But there are steps that we can take to try to socialize orphaned puppies as much as possible. "In those situations, it's important to seek advice from an experienced trainer or veterinary behaviorist to have the best chance at achieving social development," Katribe said.

Best Friends Animal Society's mission is to lead the nation to end the killing of pets in America's shelters by 2025. Because only 5.8K out of 16K communities in the United States are no-kill, each year, there are still hundreds of thousands of pets in need of homes.

This is a good opportunity to mention that a significant percentage of the dogs in shelters are purebreds. There are also intentionally bred "designer" dogs whose owners' life changes prevented them from keeping their commitment to their pets. For this reason, spaying and neutering pets is very important to the overall goal of keeping pets out of shelters and saving lives.

"Mother dogs can be spayed as little as a few days or weeks after their puppies are weaned, or sometimes even while they are still nursing – consult with your veterinarian to determine what’s best for the individual dog. Ideally, pets should be spayed/neutered before the age of four months, and before they have (or father) even one litter," Best Friends said.