Normal M-mode, Pulsed Wave and Tissue Doppler Echocardiographic Studies in Healthy Working Police Dogs

Background: Physical activity alters the cardiovascular system of dogs depending on the exercise characteristics and the animal’s physical conditioning. Little is known about the cardiovascular changes in working police dogs. This study evaluated the cardiovascular responses of working Labradors to regular exercise and various workload. Methods: Twelve working Labradors of Tamil Nadu police department that were regularly trained and exercised 30 minutes morning and evening and twelve normal household pet Labradors brought for regular checkup to Madras Veterinary College Teaching hospital were taken for the study. All the animals were subjected to physical, clinical, hematobiochemical, electrocardiographic examinations and cardiac auscultation before performing echocardiography. Those animals which showed normal recordings in all the above tests were further subjected to M-mode, Pulsed wave and Tissue Doppler echocardiography. In this study, the resting heart rate values of working groups were lesser than that of normal pet dogs. Result: The results of echocardiography showed significant increase in Interventricular septal diameter during diastole, left atrial diameter, aortic artery diameter and the left atrium to aortic diameter ratio without impairing systolic and diastolic cardiac functions in working dogs. The present study indicated that there were few changes in the echocardiographic parameters which might be a response to physiological adaptation and regular exercise.