Ultrasonography of the bovine female genital tract.

The objective of this article is to help interested readers learn to use ultrasound for female bovine reproductive tract examinations. The first section discusses practical issues for using ultrasound in the field, such as animal restraint and preparation, type of ultrasound units available, and scanning technique. The second section reviews ultrasound diagnosis of various ovarian structures. The third section explores uterine changes during the estrous cycle, in addition to uterine pathologic conditions. The fourth section covers early pregnancy, twinning, embryonic and fetal viability, and fetal anomalies. The final section considers the use of ultrasound with advanced techniques, such as embryo transfer, in vitro fertilization, and color Doppler technology, and as a complement tool in reproduction synchronization protocols for dairy cattle.