Alteration of social interactions especially prosocial behaviors – an important aspect of development – is one of the
characteristics of autistic disorders. Numerous strategies or therapies are used to improve communication skills or at least to
reduce social impairments. Animal-assisted therapies are used widely but their relevant benefits have never been
scientifically evaluated. In the present study, we evaluated the association between the presence or the arrival of pets in
families with an individual with autism and the changes in his or her prosocial behaviors. Of 260 individuals with autism - on
the basis of presence or absence of pets - two groups of 12 individuals and two groups of 8 individuals were assigned to:
study 1 (pet arrival after age of 5 versus no pet) and study 2 (pet versus no pet), respectively. Evaluation of social impairment
was assessed at two time periods using the 36-items ADI-R algorithm and a parental questionnaire about their child-pet
relationships. The results showed that 2 of the 36 items changed positively between the age of 4 to 5 (t0) and time of
assessment (t1) in the pet arrival group (study 1): ‘‘offering to share’’ and ‘‘offering comfort’’. Interestingly, these two items
reflect prosocial behaviors. There seemed to be no significant changes in any item for the three other groups. The
interactions between individuals with autism and their pets were more – qualitatively and quantitatively - reported in the
situation of pet arrival than pet presence since birth. These findings open further lines of research on the impact of pet’s
presence or arrival in families with an individual with autism. Given the potential ability of individuals with autism to
develop prosocial behaviors, related studies are needed to better understand the mechanisms involved in the development
of such child-pet relationship.