Ultrasonic instruments are used in sheep management for several important measurements and assessments, including:

1. Pregnancy Diagnosis: Ultrasound can accurately determine if a ewe is pregnant, how many fetuses she is carrying, and the stage of gestation. This is crucial for managing breeding and planning for lambing.

2. Fetal Health Assessment: By using ultrasound, veterinarians can assess the health and development of the fetuses, identifying potential issues early in the pregnancy.

3. Reproductive Health: Ultrasound can evaluate the reproductive organs of ewes, helping to identify conditions such as ovarian cysts or uterine infections that may affect fertility.

4. Body Condition Scoring: Some ultrasound devices can measure fat thickness and muscle depth, providing insights into the body condition of the sheep and their overall health.

5. Internal Organ Evaluation: Ultrasound can visualize internal organs, such as the liver and kidneys, to help diagnose diseases or conditions affecting these organs.

6. Lameness Assessment: Ultrasound can be used to evaluate soft tissues, tendons, and ligaments in the legs, helping to diagnose lameness and related issues.

Overall, ultrasonic instruments are valuable tools for improving sheep health management, optimizing breeding programs, and enhancing flock productivity.