My youngest dog, Coby, is about 7 months old. Lately, he has been sniffing his poop or the poop of his brothers. There have also been times, given the chance, that he has eaten poop. Of course, I think this is disgusting, so I wanted to find out why puppies eat poop.
One of the reasons puppies eat poop is they learn so from their mothers. To keep their cage or den area clean, the mommy will eat the poop of her young. The puppies see this happening, so they pick up on the habit.
To stop this habit, it is suggested that puppies are either on a leash outside so they can be kept away from poop or any poop should be cleaned up right away. Cleaning up the poop is the best solution as poop can carry unwanted diseases or parasites.
To learn more about why puppies (or older dogs) eat poop, see the attached article.