Demographic and aggressive characteristics of dogs in a general veterinary caseload

To best understand this article in the context of the literature on growling, snarling, snapping, and biting behavior (incidence and correlates), please see National Canine Research Council’s complete analysis here.

Article Citation:

Guy, N. C., Luescher, U. A., Dohoo, S. E., Spangler, E., Miller, J. B., Dohoo, I. R., & Bate, L. A., (2001a). Demographic and aggressive characteristics of dogs in a general veterinary caseload. Applied Animal Behaviour Science, 74, 15-28.

National Canine Research Council Summary and Analysis:

This, and the other two papers produced by the same study (Guy et al., 2001b; 2001c), is included because it probably represents the least sample bias of any large scale survey of dogs and owners. This was the initial study of the three-part series, and it focused on demographic and behavioral correlates relating to growling, resource guarding (described as “possessive aggression” by the authors) and biting behavior among dogs in Maritime Canada. The authors published two follow-up studies in the same journal issue which focused more specifically on risk factors for biting dogs and characteristics of dogs, households, and humans involved in bite incidents. This study focused on canine demographics and differences between biting and non-biting dogs.

The study subjects were clients arriving with a dog at any of 20 veterinary clinics in New Brunswick, Nova Scotia, and Prince Edward Island, Canada over a period of 3 months. A large proportion of the clients (81.4%) agreed to fill out the one-page surveys. This very high response rate yielded 3,226 surveys for analysis. Because of the high response rate and substantial sample size, this series of studies represents the best possibility of a representative sample of pet dogs in the literature on dog bites and aggression. From this initial population, two comparison groups were created. Dogs were categorized as either biters (if they were at least 1 year of age and owners reported they had bitten a household member, even if the owner thought this had happened in play), or as “non-aggressive” (if the owner reported that they had never growled, guarded resources, or bitten, again, even if the owner thought it might have been accident or happened in play). 15.6% of respondents indicated that their dog had bitten a member of the household; these dogs comprised the first comparison group.

Conflict behaviors were reported for a substantial number of canines in this population. Owners reported that 41% had growled at household members. Predictably, these trends showed that as the severity of conflict behavior increased, their frequency decreased, although it’s important to note that the authors did not specify how many of the biting dogs actually fell within the growling dog group.

Demographically, young dogs (<1 year old) bit at the highest frequency (24.6%) of any demographic grouping. This is unsurprising as many of these bites may have been in play. Intact females >1 year old bit at the lowest frequency. Neutered males were more than 3 times more likely to have bitten someone than intact females. When weight was accounted for, larger dogs were associated with reduced odds of biting, though it should be noted that more than 1/3 of participants failed to report their dog’s weight. There was also a large proportion of young dogs in this sample (>18% under 1 year old); the authors speculated this had to do with the fact that puppies typically require more veterinary care for vaccinations and neutering procedures. Some weak but statistically significant correlations were found between some breeds and incidence of growling, snarling, and biting. However, these must be weighed against the very broad question asked of pet owners with regard to these behaviors, particularly since these correlations were not seen  when the behaviors were more rigorously defined in the two follow-up studies (Guy et al., 2001b; 2001c), which eliminated dogs who had simply engaged in “harmless mouthing.”

Abstract and Link to Purchase Full Text of Original Article: