If the breeder wants competition and show dogs or has a particular purpose in mind, like breeding working dogs, they've
probably planned this litter thoroughly and taken the necessary steps to ensure the puppies are healthy and well socialized.
Therefore, if you
plan to breed your female, or if you do not
plan to spay her and the situation is such that she may become pregnant later on, you should
probably see that she has at least one
litter between the ages of five and nine months.