Breed differences in canine aggression
Eight breeds common to both datasets (Dachshund, English Springer Spaniel, Golden Retriever, Labrador Retriever, Poodle, Rottweiler, Shetland Sheepdog and Siberian Husky) ranked similarly, rs = 0.723, P < 0.05; rs = 0.929, P < 0.001; rs = 0.592, P = 0.123, for aggression directed toward strangers, dogs and owners, respectively. Some breeds scored higher than average for aggression directed toward both humans and dogs (e.g., Chihuahuas and Dachshunds) while other breeds scored high only for specific targets (e.g., dog-directed aggression among Akitas and Pit Bull Terriers). In general, aggression was most severe when directed toward other dogs followed by unfamiliar people and household members. Breeds with the greatest percentage of dogs exhibiting serious aggression (bites or bite attempts) toward humans included Dachshunds, Chihuahuas and Jack Russell Terriers (toward strangers and owners); Australian Cattle Dogs (toward strangers); and American Cocker Spaniels and Beagles (toward owners). More than 20% of Akitas, Jack Russell Terriers and Pit Bull Terriers were reported as displaying serious aggression toward unfamiliar dogs. Golden Retrievers, Labradors Retrievers, Bernese Mountain Dogs, Brittany Spaniels, Greyhounds and Whippets were the least aggressive toward both humans and dogs. Among English Springer Spaniels, conformation-bred dogs were more aggressive to humans and dogs than field-bred dogs (stranger aggression: Mann–Whitney U test, z = 3.880, P < 0.0001; owner aggression: z = 2.110, P < 0.05; dog-directed aggression: z = 1.93, P = 0.054), suggesting a genetic influence on the behavior. The opposite pattern was observed for owner-directed aggression among Labrador Retrievers, (z = 2.18, P < 0.05) indicating that higher levels of aggression are not attributable to breeding for show per se.
Title: Breed differences in canine aggression
Authors: Deborah L. Duffy, Yuying Hsu and James A. Serpell