Worms are an inevitable part of puppies’ life, so knowing what to look for and how to treat them is important. Most puppies are born with worms, because intestinal worms pass from the bitch to the puppies in utero. Therefore, it is very important to worm the bitch also. It is best to worm breeding bitches prior to mating, 10 days before whelping, and at 2 and 4 weeks after whelping. Puppies need to be wormed at 2, 4, 8 and 12 weeks of age, and then every 4 weeks until 6 months of age.