Which device is used to determine the specific gravity of urine?

The refractometer is the correct device for determining the specific gravity of urine. This instrument measures the degree to which the light is bent, or refracted, as it passes through a liquid. By analyzing the refractive index, the refractometer can provide precise insights into the concentration of solutes in the urine, which is reflected in its specific gravity.

Understanding the specific gravity of urine is crucial in veterinary medicine as it helps assess the kidney's ability to concentrate or dilute urine, providing valuable diagnostic information about an animal's hydration status and overall kidney function.

Other devices listed serve different purposes: a thermometer is used for measuring temperature, ultrasound is utilized for imaging internal structures, and an electrolyte analyzer measures specific ions and compounds in fluids. These devices do not provide information about the concentration of urine solutes or specific gravity.