H. Platamadrid et al., ULTRASONOGRAPHIC CHARACTERISTICS OF THE FOLLICULAR AND UTERINE DYNAMICS IN BELGIAN MARES, Journal of equine veterinary science, 14(8), 1994, pp. 421-423
Changes in the follicular development and visualization of endometrial
folds during the estrous cycle were characterized by ultrasonography
in Belgian mares. The secondary follicular wave was observed in only 2
of 7 mares and began in early diestrus (day 1; day 0 = day of ovulati
on). The dominant follicle of the ovulatory primary wave was retrospec
tively detected on 8.1 +/- 3 days after the day of ovulation (day 0 =
day of ovulation). The largest subordinate of the primary follicular w
ave was first detected at day 7.6 +/- 1.6. The endometrial folds were
most prominent 6.6 +/- 1.3 days before ovulation. Regression of the en
dometrial folds was observed to occur 5.5 +/- 1.5 days before ovulatio
n. In conclusion Belgian mares appear to have follicular dynamics simi
lar to those reported for Thoroughbred horses. The cyclic uterine chan
ges observed with ultrasound were more sudden, could only be observed
for a short period of time and were observed earlier in relation to ov
ulation when compared with observations made in other breeds.