Two-dimensional, m-mode and doppler-derived echocardiographic parameters in standing healthy dorper sheep

Sheep are widely used in cardiovascular system research with emphasis in translational research for the echocardiographic diagnosis of heart diseases. Several studies have proposed reference values for the various echocardiographic parameters in healthy sheep. It is known that breed, age, sex and the technique used can contribute to changes in echocardiographic parameters, the reason for investigations in Dorper sheep echocardiography. The aim of study was to establish reference two-dimensional, m-mode and Doppler-derived echocardiographic parameters in standing Dorper sheep and to determine whether there is an influence of sex on echocardiographic parameters. Sixty-five pure Dorper lambs with 3-5 months of age, weighing 29.47 +/- 3.1 kg were used. The Doppler echocardiographic was conducted in a standing position through right parasternal windows for the long axis of the left ventricular outflow tract, short axis at the level of the papillary muscles, mitral valve, aortic valve, and left atrium; and left parasternal for the cranial long axis of the right ventricular outflow tract. Significant differences between males and females were noted in left ventricular free wall (LVFW) measurements during diastole (P = 0.03) and systole (P = 0.04), as well as in output by pulmonary artery flow (DCPA) values (P = 0.03). This study successfully established Doppler echocardiographic reference values for cardiac dimensions, left ventricular systolic function, and pulmonary artery flow in healthy lamb Dorper in a standing position.