Designer breed dogs (canis lupus familiaris) with aggression and hyperactivity

Abstract We describe two cases of designer breed dogs presented for behavioural issues to the Animal Behavioural Clinic of Utrecht University. A 1.5‐year‐old, entire cockapoo male was presented for aggression towards people, hyperactivity and separation‐related behaviour. A 1‐year‐old entire labradoodle male was presented for aggression while walking the dog, aggression towards owners and ‘overarousal’ (generally high alertness and frequent state of arousal). Both dogs have a medical history that started at a young age and included gastrointestinal issues, for one dog serious repetitive otitis complaints and the other repetitive orthopaedic complaints. While medical and behavioural therapy was partly successful with the labradoodle, the cockapoo was euthanased due to recurring otitis and severe fearful behaviour. The prognosis and treatment outcome of these cases highlights how breeding with a focus on both health and behavioural soundness is crucial to animal welfare and dog owner‐contentedness.