At the heart of a dog's veterinary experience: Heart rate responses in dogs vary across a standard physical examination

Abstract

Regular veterinary care is integral to companion dog health and welfare, but fearful patients can inhibit provision of care and pose a risk of injury to veterinary staff. This study aimed to identify the physiological and behavioral responses of a sample of 30 dogs of various age and breed, to a standardized physical examination in a simulated veterinary setting. Fear was measured using heart rate (HR; beats per minute (bpm)) and continuous behavioral observations during each stage of the consult. Average HR increased significantly from waiting room (97.7 ± 19.6 bpm) to consult room (123.5 ± 21.2 bpm; P < 0.001). Approximately one third of the dogs (11/30) had heart rates peak over 180 bpm at some point during their physical examination while they were at rest, with the maximum heart rate recorded at 230 bpm. HR differed significantly between female (n = 21; 129.0 ± 26.5 bpm) and male dogs (n = 9, 110.0 ±21.2 bpm; P = 0.015); and between individual steps of the physical examination (P < 0.001). The first step, being patted by the examiner (138.0 ± 25.2 bpm), and the last step, a simulated vaccination (133.8 ± 28.7 bpm) elicited the highest HR responses, while the teeth examination had the lowest (109.6 ± 28.7 bpm). The proportion of time a dog spent with their tail tucked between hindlegs (n = 29, r = 0.392, P = 0.032) and ears positioned backwards (n = 29, r = 0.453, P = 0.012) were moderately correlated with increasing HR. The results suggest that undergoing a simulated physical examination, even in a mock veterinary setting, can be a stressful experience for dogs, and importantly varies according to the individual dog and the stage of the examination. Veterinarians should be aware how much heart rate can vary during a physical examination and a single point measure can be misleading, and that behavioral signs such as tail tucked and ears back may suggest fear related to different steps of the physical examination.