In recent years, people have made a series of improvements in veterinary B-ultrasound examination methods: (1) Selection and adjustment of veterinary B-ultrasound instruments. Different instruments and probes of different frequencies are required for examination of different parts. Due to the close cooperation between science, engineering and medicine in recent years, many high-end instruments have been equipped with variable frequency probes, wide-band probes and ultrasonic CT software, making the images clearer and more realistic, and more widely used in clinical practice. (2) Improvement of traditional examination methods. For example, Zhang Wu from Beijing proposed that prostate examination through the perineum is significantly better than lower abdominal examination. There are many reports on the proposal of new sections to make up for the shortcomings of traditional routine sections. Especially in the past two years, the application of three-dimensional technology and veterinary B-ultrasound has pushed ultrasound diagnosis technology to a new level. (3) Focus on the identification of artifacts. Many doctors have summarized many methods for identifying artifacts based on their own experience, avoiding false positives, which is of great benefit to improving the diagnosis rate. The basic principle of veterinary B-ultrasound diagnosis technology is that different media have different echoes of ultrasound, and the images formed on the display are also different. The images displayed by veterinary B-ultrasound are tomographic images of organ tissues. Due to different acoustic impedances, the various tissues of the body reflect ultrasound with varying strengths. The tissue structure with strong echoes appears as bright dot-like or sheet-like areas on the image, indicating that the tissue structure is uneven or very different from the surrounding tissue structure; while the low-echo area on the image indicates that the reflected ultrasound is weak and most of the ultrasound can pass through, indicating that the tissue structure is uniform; when ultrasound passes through liquid, there is no echo, that is, the phenomenon of no echo light spots under normal sensitivity conditions, which appears as a liquid dark area on the sonogram. The uterus of a normal, non-pregnant female dog is generally not imaged. When using a high-resolution probe, the cervix appears as an oval low-echo mass. Sometimes the tubular structure of the uterine horn can be seen on the dorsal side of the bladder and the ventral side of the colon.