Influence of transrectal and transabdominal ultrasound examination on salivary cortisol, heart rate, and heart rate variability in mares.

Pregnancy diagnostics in equine reproduction are routinely performed using transrectal ultrasonography, although it is also possible to visualize the fetus by transabdominal ultrasound examinations from the 90th day of gestation onward. We hypothesized that ultrasound examinations may stress the mare and that the gestational stage status and lactation may influence the mare's stress reaction. To investigate the stress reaction, 25 thoroughbred mares of different age, pregnancy and lactational status underwent a transrectal examination.

Effects of age, parity, and pregnancy abnormalities on foal birth weight and uterine blood flow in the mare.

Color Doppler sonography has become routine for the evaluation of high-risk pregnancies in human medicine. Previous studies documenting uterine blood flow parameters in the pregnant mare have found a decrease in peripheral blood flow resistance in the first pregnancy weeks and an increase in uterine blood flow, especially in the last trimester of pregnancy. However, these studies involved only a small number of mares.

Evaluation of pregnancy and foaling rates after reduction of twin pregnancy via transvaginal ultrasound-guided aspiration in mares.

Objective: To assess pregnancy and live foaling rates after reduction of twin pregnancy via transvaginal ultrasound-guided aspiration (TUA) in mares and evaluate effects of gestational period, localization of conceptuses, fluid aspiration volume, and combination of TUA with embryonic or fetal puncture on these outcomes.

Design: Clinical trial.

Animals: 44 mares pregnant with twins (25 to 62 days of gestation).

Iodixanol density gradient centrifugation for selecting stallion sperm for cold storage and cryopreservation.

Density gradient centrifugation can be used for selection of sperm of superior quality and removal of seminal plasma for use in artificial insemination. In this study, the use of two-layer iodixanol density gradient centrifugation was evaluated for processing of stallion semen. The protocol includes centrifugation through a 16% iodixanol top layer of 1.