anti-müllerian hormone (amh) has been observed to decrease with the development of hemorrhagic anovulatory follicles (hafs) in mares. two studies were conducted to evaluate amh concentration in mares with hafs compared to seasonally anoestrous and cyclic mares, and to elucidate changes of amh with the development of luteinised unruptured follicles (lufs). in study 1, amh and progesterone were e...

This review will focus on the main findings of our experiments that used B-mode and color-Doppler ultrasonography during the preovulatory period to study the morphological and blood flow/perfusion changes of the preovulatory follicle in mares. The topics to be addressed herein will be: ultrasonographic characteristics of the preovulatory follicle; B-mode echotextural changes of the follicle wal...

Recent innovations in ultrasonographic techniques have advanced our knowledge on the effects of seasonality on the changing populations of antral follicles in mares. The seasonal patterns in the monthly incidence of ovulations is at least partly a function of daylength, even at latitudes as low as 10o where the longest day may be less than 13 hours. Follicle dynamics involves a mid-anovulatory ...

Reproductive records of the entire lives of two mares with abnormally high incidence of multiple ovulation and hemorrhagic anovulatory follicles were analyzed retrospectively. Chi-square analysis was used to test statistically the effect of cloprostenol, a prostaglandin F2 analog, on the incidence of multiple ovulations, hemorrhagic anovulatory follicles, and its ultrasonographic appearance. A ...

The effect of pulsatile infusion of gonadotropin-releasing hormone (GnRH) on follicular function was evaluated in nutritionally induced anovulatory beef cows. After 4 (short; n = 12) or 18 wk (long; n = 12) of anovulation, cows were randomly assigned within anovulatory group to either 2 microg of GnRH treatment or saline (control; i.v.) every hour for 5 d. Ovarian structures were monitored by d...

Anti-Müllerian hormone (AMH) has been observed to decrease with the development of hemorrhagic anovulatory follicles (HAFs) in mares. Two studies were conducted to evaluate AMH concentration in mares with HAFs compared to seasonally anoestrous and cyclic mares, and to elucidate changes of AMH with the development of luteinised unruptured follicles (LUFs). In study 1, AMH and progesterone were e...

With the purpose of measuring the duration of the functional life-span (FLS) of the anovulatory follicle in women under continuous low-dose progestogen treatment, the oestradiol curve of Norplant implant users was retrospectively analysed. From all the data collected during the previous 5 years at the Department of Biomedical Research at the Family Planning Clinic of Profamilia, Santo Domingo, ...

Follicle growth and associated changes in circulating hormone concentrations were evaluated after follicle ablation in mares (n = 13) during four 13 day periods beginning at means of -98.5, -61.4, -26.0 and 10 days from the first ovulation and corresponding to mid-anovulatory, early-transitional, late-transitional and ovulatory periods, respectively. During each period, all follicles > 5 mm in ...

The present paper describes LH and FSH secretion, follicle development and ovulation in sows that were subjected to a limited nursing regimen. From Day 14 of lactation, 32 sows were separated from their piglets for 12 h every day (intermittent suckling; IS). Half the sows had boar contact during separation. Nine of 32 sows ovulated spontaneously within 14 days from initiation of IS. The frequen...

Most estrous cycles in cows consist of 2 or 3 waves of follicular activity. Waves of ovarian follicular development comprise the growth of dominant follicles some of which become ovulatory and the others are anovulatory. Ovarian follicular activity in cows during estrous cycle was studied with a special reference to follicular waves and the circulating concentrations of estradiol and progestero...