An electrocardiography device and method that is able to obtain the electrocardiogram of a freely moving animal. The device and method utilizes at least two catheters to obtain the electrical signals from the heart of the animal being tested. The catheters are filled with an electrically-conductive, physiological solution and are used in combination with at least two test leads that are able to transfer the electrical signals from the animal to an ECG monitoring device. The device and method also allows for fluids to flow through the catheters to other devices such as a blood sampler controller and/or an infusion pump.