Gestational enrichment of commercial breeding dams (Canis familiaris) influences offspring behaviour

The benefits of environmental enrichment for kennelled dog welfare have been widely demonstrated. Research in rodents shows that provision of maternal environmental enrichment during gestation can also influence the behavioural development of the offspring. However, the effects of prenatal enrichment on puppy behavioural development remains to be explored in domestic dogs. The current study investigated the effect of maternal enrichment during gestation on the behaviour of puppies bred at a commercial dog breeding establishment (CBE). During the last four weeks of gestation, mothers were exposed to either baseline management conditions (control: N = 5) or additionally subjected to an enrichment protocol based on positive human interaction (enriched: N = 5). Mother-puppy interactions were recorded throughout the first three weeks postpartum to determine the amount of maternal care provided to each litter. Subsequently, the behavioural responses of puppies (control: N = 29, enriched: N = 30) were assessed in an isolation test, a human greeting test, and a novel object test when puppies were ∼8 weeks old. Results showed that prenatal enrichment affected puppies’ behaviour in a sex-dependent manner. In the isolation test, prenatal enrichment significantly reduced ‘Exploration’ levels in male puppies but not in females and tended to reduce ‘Activity’ levels in male puppies. Furthermore, as mother-puppy interactions increased, vocalisations decreased in male puppies compared to females during the isolation test. In the novel object test, maternal enrichment was linked to higher ‘Confidence’ scores in female puppies but lower in male puppies. Furthermore, ‘Exploration’ levels were significantly reduced in male puppies from enriched mothers but not in females. Moreover, there was a positive relationship between the amount of maternal care provided and puppies’ explorative behaviour. Similarly, in the human greeting test, puppies’ affiliative behaviour towards a person increased with increasing maternal care. This is the first study to provide evidence in dogs that maternal enrichment during gestation influences offspring behaviour. Results suggest that prenatal enrichment may modulate stress coping strategies in a sex-dependent manner. However, other factors such as the amount of maternal care provided, breed and litter size should also be considered.