Reported behaviour problems in pet dogs in Denmark: Age distribution and influence of breed and gender

In the period 1987-1991 the consultant service established by the Danish Animal Welfare Society and the Danish Civil Dog Training Association reported 3975 problems in relation to pet dogs in Denmark. With nine categories of problem behaviour a total of 2719 problems were recorded in 2238 dogs. The data were analysed for the influence of breed, gender and age on the risk of developing behaviour problems. The analysis was designed as a case-control study using two control groups: (1) dogs registered by Danish Kennel Club in a 5-year period and (2) dogs treated at The Royal Veterinary and Agricultural University, Copenhagen, Denmark in a 4-month period. Thirteen breeds or breed groups including mixed breeds were compared with a reference group consisting of Labrador Retrievers. Compared with the reference group, Alsatians seemed to have higher risks of aggression towards other dogs, aggression towards strangers and general anxiety. For Cocker Spaniels higher risks of aggression towards the owner, agression towards strangers and indoor urination/defecation were found. Collies seemed to have higher risks of aggression towards strangers, indoor urination/defecation and general anxiety. Furthermore, a higher risk of general anxiety was found in Poodles and Fox Terriers. Generally, Dachshunds, a group consisting of all terriers excluding Fox Terriers and mixed breeds, seemed to have a low risk of behaviour problems. Compared with females, males seemed to have a lower risk of general anxiety and a higher risk of problems related to lack of training and all kinds of aggression. About 80% of the behaviour problems were reported within the first 3 years of life. Only 5.5% of the dogs were suggested to be or were in fact euthanized.