Modeling Aggression in Animals: Linking Gut Microbiota and Aggression

From a “microbiota-gut-brain axis” perspective, animal models suggest that gut microbiota affects aggression. Behavioral studies using germ-free mice indicate that maintaining a healthy gut microbiota early in development can subsequently mitigate aggressive behavior in the host. Mice pups, whose gut microbiota was affected by antibiotics from gestation through weaning, exhibited aggression; hamsters whose maternal gut microbiota was disturbed by antibiotics were similarly affected. However, few clinical or animal studies have reported targeting aggression through gut microbiota intervention. Based on animal models, probiotic and prebiotic supplementation and fecal microbiota transplantation are hypothesized as possible therapeutic options to reduce aggression. Therapeutic efficacy may be greatest if intervention occurs early in development. In addition, stabilizing the maternal gut microbiota may prevent or reduce future aggression in offspring. This chapter reviews the effects of the gut microbiota on host aggression, focusing on animal studies.