Reduced cardiac functional capacity as a consequence of the double-muscled conformation selection in the Belgian White and Blue breed

Abstract

In this hemodynamic study (conducted in 2 parts), cardiac function has been compared in double-muscled calves and in calves with conventional conformation. Simultaneous measurements of cardiac output, cardiovascular pressures and ventricular volumes showed that in the bovine species, the double-muscled conformation selection induces a significant reduction of the cardiac output and the stroke volume. This reduction in global cardiac performance is not due to a lower heart rate, a lower ventricular preload or an higher after load, but was rather associated with a reduced myocardial contractility and a lower indexed volumetric capacity.