Do dog breeds differ in pain sensitivity? Veterinarians and the public believe they do

Abstract

Humans do not respond to the pain of all humans equally; physical appearance and associated group identity affect how people respond to the pain of others. Here we ask if a similar differential response occurs when humans evaluate different individuals of another species. Beliefs about pain in pet dogs (Canis familiaris) provide a powerful test, since dogs vary so much in size, shape, and color, and are often associated with behavioral stereotypes. Using an on-line survey, we asked both the general public and veterinarians to rate pain sensitivity in 28 different dog breeds, identified only by their pictures. We found that both the general public and veterinarians rated smaller dogs (i.e. based on height and weight) as being more sensitive to pain; the general public respondents rated breeds associated with breed specific legislation as having lower pain sensitivity. While there is currently no known physiological basis for such breed-level differences, over 90% of respondents from both groups indicated belief in differences in pain sensitivity among dog breeds. We discuss how these results inform theories of human social discrimination and suggest that the perception of breed-level differences in pain sensitivity may affect the recognition and management of painful conditions in dogs.

Fig 1. Average pain sensitivity ratings for each dog breed, shown separately for the general public and veterinarian respondents.

The scale ranged from 0 = not at all sensitive to 100 = most sensitive imaginable. Median pain sensitivity ratings between the veterinarians and general public were compared using two-sample t-tests. p-values are *** = 0.001, * = 0.05.

Fig 2. Box-and-whisker plot (median, interquartile range, and 1.5 interquartile range) of individual standard deviations across ratings of dog breeds for each level of response to the question regarding extent of belief in a difference in sensitivity for dog breeds.

Standard deviations were significantly different for each group (corrected p < 0.05 for each comparison). This figure shows aggregate responses across the two groups; number of individuals in each group were: A great deal (n = 708), A moderate amount (n = 1007), A little (n = 335), and Not at all (n = 81).