Evaluation of plasma cortisol levels and behavior in dogs wearing bark control collars

Abstract

On wk −1, 24 healthy mixed breed kennel dogs were screened by physical examination, complete blood count, serum biochemistry, and plasma cortisol measurement. Dogs were tested to ensure they barked at an unfamiliar dog. Dogs were randomly assigned to control, electronic bark collar or lemon spray bark collar groups ( n = 8 per group). On wk 0 (acclimation baseline), dogs wore inactivated collars 30 min/day for 3 consecutive days. On wks 1 and 2, dogs wore an activated collar 30 min/day for 3 consecutive days. Controls wore an inactivated collar. The bark stimulus was an unfamiliar dog walked in front of the run, three times, 30 s per presentation. Plasma cortisol was measured wk −1, wk 0 d 3, wk 1 d 1, wk 1 d 3 and wk 2 d 3. ACTH was measured wk 0 d 3 and wk 1 d 1. Barking and activity were measured each session. Results Dogs wearing electronic or lemon spray collars barked less than controls ( P < 0.05) by the 2nd day wearing an activated collar, with no significant difference in barking between collars. Mean numbers of collar corrections per dog on the 1st day wearing an activated collar were 4.0 (electronic) and 2.0 (lemon spray); the values decreased to 0 for both collars on the 3rd day. ACTH levels did not differ among groups ( P > 0.05). Mean plasma cortisol levels were within the reference range for all groups throughout the study. Overall, there was a significant time effect ( P < 0.05) but no significant difference in plasma cortisol between the control, lemon spray and electronic collar groups ( P > 0.05). Activity did not change significantly over time ( P > 0.05). Conclusion Electronic and lemon spray bark collars significantly reduced barking, with no significant difference between collar types. Dogs with either type of bark collar had an increase in plasma cortisol the 1st day wearing the activated collar, but this was not statistically significant ( P > 0.05). There was no statistically significant difference in plasma cortisol levels between dogs wearing control, lemon spray or electronic collars.