Identification of fear behaviors shown by puppies in response to nonsocial stimuli
Publication Type: |
Journal Article |
Year of Publication: |
2018 |
Authors: |
Hannah E. Flint, Jason B. Coe, James A. Serpell, David L. Pearl, Lee Niel |
Publication/Journal: |
Journal of Veterinary Behavior |
Keywords: |
canine behavior, development, fear, puppy |
ISBN: |
1558-7878 |
Abstract:
Understanding fear behavior in puppies is important for dog welfare, prevention of behavioral issues, and ensuring research assessments are accurate. Further research is necessary to determine which specific behaviors puppies show when they are fearful and whether these behaviors are similar to those seen in older dogs. We assessed which puppy behaviors are associated with mild- to- moderate fear in the presence of social and nonsocial stimuli. However, no puppies showed fear responses toward social stimuli, so only results for nonsocial stimuli are presented. Puppies (<6 months; n = 25) were introduced into a 3.7- m long run and trained to approach the far end to obtain a food reward. After training, each puppy completed 4 trials with noisy or unpredictable novel objects (nonsocial stimuli), 2 trials with strangers (social stimuli), and 6 control trials with no stimuli. All sessions were video-recorded, and frequencies and durations of behaviors performed during each nonsocial stimuli trial, and the immediately preceding blank control trial, were recorded (n = 193). For each trial, the puppy's behavioral response was categorized as “fearful” if the latency to approach was greater than the mean + 2 standard deviations of the blank control trials. Linear, logistic, and Poisson mixed models, with puppy as a random effect, were used to model behavior durations, presence of behavior (yes/no), and counts of how many times the puppy performed the behavior in a given trial, respectively. The following behaviors occurred more in trials with a “fearful” response in comparison to blank control trials: lowered posture (P < 0.001), lowered tail (P = 0.001), freezing (P < 0.001), retreating (P < 0.001), flinching (P < 0.001), paw lift (P = 0.006), and barking (P = 0.002). Sniffing (P < 0.001), locomotion (P < 0.001), and panting (P < 0.001) occurred less in trials with a “fearful” response. No significant difference was found for ear position, lip licking, and tail wagging. Yawning, shaking, elimination, whining, and growling occurred too infrequently for analysis. These results indicate that postural, retreating, and barking behaviors are the most reliable indicators of mild- to- moderate fear in puppies in situations where they are able to control their approach to nonsocial stimuli intended to elicit fear.