Physiological effects of human/companion animal bonding.

Blood pressure, heart rate, and respiratory rate were recorded in 24 subjects during 3 9-minute measurement sessions in which they petted an unknown dog, petted a dog with whom a companion bond had been established, or read quietly. Based on the findings of this study, several conclusions were drawn: (1) There is a significant difference in changes over time in both systolic and diastolic blood pressure between petting a dog with whom a companion bond has been established and petting a dog with whom no bond exists; (2) the decreases in both systolic and diastolic blood pressure that occur during petting a dog with whom a companion bond has been established parallel the relaxation effect of quiet reading; and (3) there is a " greeting response" to the entry of a dog with whom a companion bond has been established, which results in significantly higher systolic and diastolic pressures than the response either to an unknown dog or to reading.