Plasma follicle-stimulating hormone (FSH) was evaluated in gilts from two studies in which ovulation rate was increased through direct selection for number of corpora lutea (CL) to determine whether selection for ovulation rate affected FSH secretion during prepubertal development. In the first study, 76 control and 110 selected gilts of University of Nebraska gene pool lines were bled twice du...

BACKGROUND The likelihood of conception is increased if intercourse is timed to coincide with the fertile period (5 days up to ovulation). However, to be effective, this requires good awareness of the day of ovulation. The aim of this study was to examine the accuracy of women's perceived ovulation day, compared with actual fertile days, in a cohort of women trying to conceive. MAIN OUTCOME M...

A method for monitoring oviductal isthmic motility in sows incorporating a computer programme (Polyview) was developed. This method was found to be reliable and easy for recording and analysing data. Isthmic motility patterns were monitored from 11 h prior to and up to 36 h after ovulation in 13 unrestrained multiparous sows during their second oestrus after weaning. The amplitudes and frequenc...

A single injection of PMS induces ovulation in immature rats on the third day morning after the treatment. The second estrus occurred 9 days after the first ovulation. Follicles of the succeeding cycle developed the capacity to ovulate 3 days after the first ovulation in 3 out of 5 rats, but could not be maintained in an ovulable state during the next 24 hr. When supplementary PMS was given jus...

The present study investigated whether kisspeptin-G protein-coupled receptor 54 (GPR54) signaling plays a role in mediating mating-induced ovulation in the musk shrew (Suncus murinus), a reflex ovulator. For this purpose, we cloned suncus Kiss1 and Gpr54 cDNA from the hypothalamus and found that suncus kisspeptin (sKp) consists of 29 amino acid residues (sKp-29). Injection of exogenous sKp-29 m...

The present study was undertaken to determine changes in circulating levels of immunoreactive (ir)-inhibin, FSH, LH, estradiol-17beta, progesterone, and testosterone during the ovulatory cycle of Shao ducks. Serial blood samples were taken from two groups of laying ducks for measurement of ir-inhibin, gonadotropins, and steroid hormones at 2 h intervals for 24 h. Plasma concentrations of ir-inh...

Ovulation in camelids is induced by an unidentified protein in the seminal plasma of the male termed 'ovulation-inducing factor'. This protein has been reported to be a 14-kDa protein under reducing conditions, which, when purified from seminal plasma, induces ovulation in llamas. The identification of this protein and investigation of its potential to induce ovulation in camelids may aid the d...

this study investigated the effect of gnrh analogues on inducing ovulation of dominant follicle (df)and subsequent corpus luteum (cl) lifespan in the presence of norgestomet implant in holstein heifers. onday 6 to 8 of the estrous cycle (day 0 of the experiment), all heifers (n=15) received norgestomet implantfollowed by prostaglandin injection on days 0 and 1. on day 4, group 1 (n=4) and 2 (n=...

Administration of gonadotropin-releasing hormone (GnRH) induces a surge of luteinizing hormone and ovulation in a variety of species, including human beings. Our objectives were to determine the effect of follicle size at the time of ovulation on corpus luteum function and establishment and maintenance of pregnancy in cows in which ovulation was either spontaneous or induced with GnRH. GnRH-ind...

BACKGROUND The purpose of this study was to assess the accuracy of ovulation detection by the DuoFertility(®) monitor compared with transvaginal ultrasound in infertile women with regular menstrual cycles. METHODS Eight infertile patients, aged 27-40 years, with a body mass index of 19-29, regular menses, normal ovaries on pelvic ultrasound scan, and normal early follicular luteinizing hormon...