Breed-dependent differences in the onset of fear-related avoidance behavior in puppies

Please note: The following is a summary of a research article, referenced at the end of this page, by Mary Morrow, Joseph Ottobre, Ann Ottobre, Peter Neville, Normand St-Pierre, Nancy Dreschel, Joy L. Pate.


Fear can greatly impact the behavior of individuals as the environment around them changes. In fact, there has not been much material previously published on puppy behavior and development, “especially relating to the development of fear” (Morrow, J. Ottobre, A. Ottobre, Neville, St-Pierre, Dreschel, Pate, 2015). This study aimed to determine when “fear-related avoidance behavior” develops in different breeds (Morrow et al., 2015). More specifically, the researchers hoped to “identify, compare, and contrast the onset of fear-related avoidance behavior and concurrent concentrations of salivary cortisol among 3 specific breeds of purebred puppies” (Morrow et al., 2015). A total of 98 purebred dogs--33 Cavalier King Charles spaniels, 32 Yorkshire terriers, and 33 German shepherd dogs--participated in the study (Morrow et al., 2015). These 3 breeds were chosen because they offered enough contrast in their breed characteristics and genetic backgrounds (Morrow et al., 2015). From ages 4 or 5 weeks to 10 weeks, they participated in a series of weekly tests (Morrow et al., 2015). For each subject, the tests were administered in a random order, one after another (Morrow et al., 2015). The control groups, 14 per breed, were put in the same tests but were not exposed to the stimuli (Morrow et al., 2015). Observers noted if the puppies reacted with a fear-related avoidance behavior or retracted into a crouched position (Morrow et al., 2015). Furthermore, saliva was collected from the puppies before and after the tests to test for varying levels of salivary cortisol (Morrow et al., 2015). [Unfortunately, not enough saliva was collected from the Yorkshire terriers for analysis (Morrow et al., 2015).]


The first test, “Novel Item Test” showed the puppies a moving, light-emitting, and noise-producing toy duck for 5 seconds (Morrow et al., 2015). Next, the “Seesaw Test” put the treatment puppy in the center of a balanced fulcrum for 10 seconds (Morrow et al., 2015). Another test was the ‘Step Test,” where researchers observed if the treatment puppies moved around or off of a platform made proportional to their sizes (Morrow et al., 2015). Finally, the “Loud Noise Test” involved an abrupt, intense noise made by dropping the step from the Step Test before the puppy (Morrow et al., 2015). [The puppy could see the process occurring (Morrow et al., 2015).]


The results show that Cavalier King Charles spaniels’ levels of cortisol increased significantly after tests, but the German shepherds’ did not change significantly (Morrow et al., 2015). Also, all puppies behaved similarly until 6 weeks, when the Cavalier King Charles spaniel puppies moved less than the other two breeds on the Seesaw Test (Morrow et al., 2015). At 7 weeks, the same trend continued for the Novel Item, Loud Noise, and Seesaw Test (Morrow et al., 2015). From 8 to 9 weeks, “Yorkshire terriers and Cavalier King Charles were similar in mobility during the Novel Item and Loud Noise test,” while “the Cavalier King Charles spaniel demonstrated the least amount of movement in the Seesaw Test for the duration of the study” (Morrow et al., 2015).


Ultimately, the study maintains that “emotional and behavioral development” and the “onset of fear-related avoidance” changes for different dog breeds (Morrow et al., 2015).


Reviewed by: Sofia Hsu, 11/19/18




M. Morrow, J. Ottobre, A. Ottobre, P. Neville, N. St-Pierre, N. Dreschel, J. Pate Breed-dependent differences in the onset of fear-related avoidance behavior in puppies. J. Vet. Behav: Clin. Appl. Res., 10 (4) (2015), pp. 286-294

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