Une vie de chiot

Why is the dog, man's best friend, so jovial and so loyal to his master? Are these characteristics written in his genes? Although the affectionate personality of these companions seems almost innate, the way in which their life begins has a definite impact on their future behavior. A team attended the first months of several puppies of different breeds, from birth to adoption and the first steps in their new home. How do puppies manage to trust a previously unknown person to the point of forming an indestructible bond with them?