We do the very best we can by carefully selecting breeding partners so that we get the best genetic mix possible in the puppies. But once a dog is bred, their genes are fixed. That can’t be changed. But genes can express themselves in a very wide variety of ways. The same gene or set of genes that can cause desired behaviors (such as playing catch or fetching) can also cause undesired behaviors (such as chasing cats or small children). Studies have also shown that the prenatal care a dam gets can affect the health and personalities of her pups. This is true for both prenatal health support and prenatal emotional support.
Puppies have specific developmental stages, and these stages correspond to behavioral markers. A good breeder also needs to understand puppy development, be able to identify these stages, and be able to understand how to properly address these stages. What is highly beneficial in one stage, can be severely detrimental in another, and properly identifying and handling behavioral stages is absolutely critical to producing strong, emotionally sound puppies.
We use Puppy Culture and Avidog Transformational Puppy Rearing principles to work with your puppy according to its individual developmental needs. We do a huge amount in the time they are with us, and we get a lot done. But that's only the beginning, and it's important for you to follow through with continuing and reinforcing that work once your puppy goes home. Maintenance of impulse control, continuation of socialization, and continuation of training are important keys for your puppy's continued success.