If you are not familiar with animal ultrasound, the image may look like a rotating gray tone on the screen. Explanation requires an understanding of anatomy and physiology, as well as knowledge of the functions of veterinary ultrasound technology.

Consider the sonar produced by bats in flight. Bats emit high-frequency sounds, then bounce back from nearby objects and return to the bat. Animals use the intensity, direction, and time of the returning sound to determine the location of these objects and avoid collisions.

The transducer (probe) of the animal ultrasound system emits high-frequency sound waves, which propagate to the tissues below the surface of the body and reflect structures along the way. Dense or rigid structures do not allow sound waves to pass through, so most of them reflect back to the sensor. This structure will generate strong echoes and appear bright white on the screen. In contrast, fluids propagate sound waves perfectly; No return signal means that the fluid appears black on the screen.

Of course, most organizations fall somewhere in between, presenting some gray color. Fluid with highly fragmented cells may appear black with floating gray or white spots (snowflake effect). The liver or spleen parenchyma will be medium gray, while the surface of fetal bones or bladder stones will be almost white.

The time required for the animal to return the required signal using B-ultrasound describes how far the structure of the probe is from the surface of the probe. For example, if there is a long delay from signal transmission to its return, ultrasound interprets it as a structure located below the surface, so it will appear lower on the screen in the generated image.

In this pregnancy image, it will be found that the fluid inside the uterus is black, the feces and uterine tissue have different gray shadows, and the fetal bones are white. The top of the image corresponds to the surface of the transducer, while the bottom is the deepest part of the imaged tissue.

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