In the present study the use of abdominal color Doppler ultrasonography in dogs and cats is reported. This technique allows a better differentiation from hypoechoic structures (e.g. vessels, cysts, dilated biliary ducts, ureters) and facilitates the positioning of the conventional Doppler-sample volume for more detailed measuring. In addition the distinction from masses in the region of the urinary bladder wall that could be tumors or adherent inflammatory clots, the evaluation of the renal hilar area and differentiation from renal vessels and ureter, the scanning and assessment of the gravid or inflamed uterus, the examination of inflamed or twisted testicles, the early diagnosis of splenic torsion or splenic vein thrombosis or the detection of an aortic thrombus is possible by color Doppler ultrasonography.