Evaluation of young and adult dogs' reactivity

Many authors have tested puppies' behavior early to detect adult behavioral disorders. Our pilot study aims to investigate puppies' reactivity toward tolerance of new situations and the consistency of behavior between puppy and adult dog. Seven tests (tunnel, direct looking, sudden noise, retrieving buster-ball, problem solving, bowl removal, and approaching) were used to evaluate the reactivity of 32 German shepherd dogs at 5, 7, and 9 months of age. Among these dogs, 17 were chosen by physical and behavioral traits to continue the training program up to adulthood (choice group) and administered the same tests at the age of 2 years. Through the observation of behaviors, the tests aim to assess sociality, exploratory and retrieving tendency, learning ability, playing aptitude, and tendency toward offensive aggression. The behaviors were ranked by degree of reactivity, and ranks were used as scores. The effects of gender and group on the 5- to 9-month reactivity profiles of all the puppies were estimated with a repeated-measures model. In the choice group, the behavior changes from 9 to 24 months and their dependence on gender were estimated with an analogous model. All puppies became more self-confident between 5 and 9 months. At 9 months, behavior was slightly better in males and in the choice group. Between 9 and 24 months, self-confidence, attentiveness, and ability to solve problems and retrieve objects improved, whereas playfulness decrease. Behaviors at 9 and 24 months showed very low variability, which indicated their very high similarity