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Ovulatory Cycle (ovulatory + cycle)
Selected AbstractsReproductive ecology of the reef manta ray Manta alfredi in southern MozambiqueJOURNAL OF FISH BIOLOGY, Issue 1 2010A. D. Marshall The application of a photographic identification methodology using the unique ventral surface markings (natural spot patterns) of an observed population in southern Mozambique enabled many aspects of the reproductive ecology of reef manta rays Manta alfredi to be examined. The region encompassing the study site was identified as a mating ground for M. alfredi based on observations of mating events and fresh mating scars on females. The distribution of these pectoral fin scars was highly biased and indicated a strong lateralized behavioural trait, with 99% of these scars occurring only on the left pectoral fin. No other elasmobranch has been reported to display behavioural lateralization. The study region also acts as a birthing ground, with individuals typically giving birth in the austral summer period after a gestation of c. 1 year. Reproductive periodicity in M. alfredi was most commonly biennial, but a few individuals were pregnant in consecutive years, confirming an annual ovulatory cycle. The production of a single pup appears to be the normal situation, although observations in the wild as well as during opportunistic dissections of individuals killed by fisheries revealed that two pups are conceived on occasion. Many aspects of the study have contributed to the limited baseline data currently available for this species and have highlighted the potential need for more conservative conservation strategies. [source] Regulation of prostaglandin synthesis in ovaries of sexually-mature zebrafish (Danio rerio)MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 11 2009Andrea L. Lister This study investigates the regulation of prostaglandin (PG) synthesis in the ovaries of sexually-mature zebrafish (Danio rerio). We examined the ovarian expression of genes within the arachidonic acid (AA) pathway, and the ovarian levels of 17,,20,-dihydroxy-4-pregnen-3-one (17,,20,-P), 17,-estradiol (E2), and PGF2, in spawning and nonspawning fish during the ovulatory cycle. Real-time RT-PCR analysis revealed that the expression levels of cytosolic phospholipase A2 (cpla2) and cyclooxygenases (COX)-2 (ptgs2) in ovarian fragments and in isolated full-grown follicles of spawning fish were highest at 6:00 when ovulation was expected to occur. In nonspawning fish, cpla2 expression levels declined over time while ptgs2 expression displayed the same temporal pattern as in spawning fish. Elevated levels of 17,,20,-P in the spawning fish occurred at 3:30, but there were no changes in the nonspawning fish. In other studies conducted to investigate the hormonal regulation of AA pathway genes, fish exposed via the water for 24 or 96,hr to 17,,20,-P or E2 exhibited reduced ovarian expression levels of COX-1 (ptgs1) and PG E synthase-2 (ptgsl), and E2 reduced the expression of cpla2. Injection of human chorionic gonadotropin (hCG) (100,IU) led to increased expression levels of cpla2 and ptgs2 at 2 and 18,hr post-treatment, but consistently reduced ptgs1 and ptgsl expression. In these fish, ovarian levels of 17,,20,-P were elevated at all time points and PGF2, levels in the hCG-treated group were significantly higher than the control fish at 18,hr. Collectively, these in vivo results suggest that gonadotropins and steroids are involved in the regulation of the AA pathway in ovarian follicles of zebrafish. Mol. Reprod. Dev. 76: 1064,1075, 2009. © 2009 Wiley-Liss, Inc. [source] Investigation of Cervical Patency and Uterine Appearance in Domestic Cats by Fluoroscopy and ScintigraphyREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2002K Chatdarong Contents The cervical patency of six domestic female cats was monitored under sedation by infusion of contrast medium (Omnipaque) into the cranial vagina during early oestrus, mid-oestrus, late oestrus and interoestrus or a radiopharmaceutical (99mTc-HSA) during mid- and interoestrus in a non-ovulatory oestrous cycle. The transport of the contrast medium or the radiopharmaceutical through the cervix and within the uterine horns was observed under fluoroscopy and with the aid of scintigraphy. In three of the queens, transcervical transport of contrast medium was demonstrated in all stages of oestrus, in one queen during mid-oestrus, late oestrus and 1 day after oestrus, and in two queens only during late oestrus. The relations between the cervical patency to the contrast medium and the oestrous behaviour, cornification of the vaginal cells and the serum oestradiol-17, concentration were evaluated, and a relationship was found between the cervical patency and the degree of vaginal cornification. Transcervical transport of the radiopharmaceutical was observed in three queens during mid-oestrus. When the cervix was open, hysterography under a fluoroscope and hysteroscintigraphy were performed. The fluoroscopic and scintigraphic recordings revealed the patterns of the uterine contractions during oestrus in both ascending and descending directions, and the movement of the uterine contents back and forth between the uterine horns. The hysterograms were classified according to the shape of the uterine horns and the appearance of the endometrial lining. Spiral-shaped uterine horns with a smooth inner contour were observed in two queens, and a corkscrew appearance with irregular filling defects in the uterine lumen was shown in two queens that had developed subclinical cystic endometrial hyperplasia. These findings demonstrated that fluids or particles deposited in the cranial vagina of the cat can be transported into the uterus during some stages of the oestrous cycle. The fluoroscopic and scintigraphic techniques developed in this study may be further modified to permit more detailed studies of uterine contractile patterns and sperm transport in the feline female reproductive tract. Hysterography proved useful to diagnose uterine disease. The information on cervical patency is of value also for the development of techniques for artificial insemination in this species, and should be studied also in the ovulatory cycle. [source] Measurement of urinary and fecal steroid metabolites during the ovarian cycle in captive and wild Japanese macaques, Macaca fuscataAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2001Shiho Fujita Abstract We measured the concentration of steroid hormones from urine, feces, and blood samples of two captive Japanese macaques, Macaca fuscata, during nonconceptive ovarian cycles to compare the patterns of the excreted steroids with those of circulating steroids. Urine and feces were analyzed for estrone conjugates (E1C) and pregnanediol-3-glucronide (PdG) using enzyme immunoassays (EIAs), while plasma was analyzed for estradiol-17,(E2), progesterone (P), and luteinizing hormone (LH) using radioimmunoassays (RIAs). Urinary and fecal E1C and PdG levels were approximately parallel to plasma E2 and P levels, respectively. The E1C profiles of daily urinary and fecal samples revealed a midcycle peak, followed by a sustained PdG increase lasting up to two weeks from the E1C peak. A fecal E1C peak was one day later than the urinary E1C peak. One of the captive females exhibited a discrete plasma LH peak, one indicator that ovulation has occurred, on the day following the urinary E1C peak, i.e., the same day of fecal E1C peak. We measured excreted steroids in nine wild females and determined the timing of ovulation by comparing fecal steroid profiles to those obtained in captive monkeys. Data from wild females indicated that eight of nine females conceived during their first ovulatory cycle of the sampling period, whereas the remaining female failed to conceive during the sampling period even though she ovulated. In the eight females that conceived, E1C increased again following the detected or estimated E1C peak, with levels comparable to the preovulatory peak levels, and sustained elevations of PdG for over 40 days. These data illustrate that the urinary and fecal profiles of ovarian steroid excretion obtained through the application of these noninvasive techniques provide an accurate approach for monitoring conceptive and nonconceptive ovarian cycle in captive and free-living Japanese macaques. Am. J. Primatol. 53:167,176, 2001. © 2001 Wiley-Liss, Inc. [source] What Females Tell Males About Their Reproductive Status: Are Morphological and Behavioural Cues Reliable Signals of Ovulation in Bonobos (Pan paniscus)?ETHOLOGY, Issue 7 2002Karin E. Reichert In many Old World primate species, female attractivity increases during the tumescent phase of the sexual swelling for a period that lasts considerably longer than oestrus-related attractivity in other mammals. We examined the reliability of the swelling as an indicator of ovulation in captive bonobos, a species with a long and variable phase of maximum tumescence. Using a combined approach of (1) observations of sexual behaviour, (2) visual scoring of the sexual swelling and (3) analysis of faecal progestin to assess the timing of ovulation during 23 ovulatory cycles of eight adult females, we found that in 30% of these cycles the presumed day of ovulation did not fall within the period of maximum tumescence. When ovulation did occur during maximum swelling, it was more closely related to the end rather than the onset of the maximum swelling period. However, the pattern of sexual swelling was not a reliable indicator of ovulation. In addition, sexual behaviour of both sexes increased in frequency with the degree of the swelling but not around the time of ovulation. We conclude that swellings in bonobos provide honest information on the probability of ovulation, but not its exact timing, and that therefore the `obvious ovulation'-hypothesis cannot explain the function of sexual swellings in bonobos. [source] The impact of developmental conditions on adult salivary estradiol levels: Why this differs from progesterone?AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2008Alejandra Núñez-De La Mora Women living in energetically stressful conditions have significantly lower baseline salivary steroid levels compared to those in affluent environments. Developmental hypotheses suggest that interpopulation variation in ovarian function results from contrasting environments experienced during growth. We use a migrant study of Bangladeshi women to test this hypothesis. We compared middle-class women (19,39 years) who migrated to London, UK, at different life-stages (pre and postmenarche), with Bangladeshi sedentees, second-generation British-Bangladeshis, and white British women living in similar London neighborhoods (total n = 227). We analyzed levels of salivary estradiol for one menstrual cycle, together with data on anthropometry, diet, lifestyle, and migration and reproductive histories. Results from multiple linear regression models, controlling for anthropometric and reproductive variables, show no significant differences in baseline estradiol levels between groups whether all cycles or just ovulatory cycles are analyzed. We also found no correlation between age at migration or time since migration on estradiol levels, nor between adult estradiol levels and age at menarche. Our results differ from previous reports of significantly lower salivary estradiol levels in populations living in more extreme ecological settings. They also contrast with our previous findings of significant intergroup differences in baseline levels of salivary progesterone. However, women who spent their childhood in Sylhet have a lower proportion of ovulatory cycles compared to women who developed in Britain. These group differences in ovulation frequency indicate more qualitative effects of contrasting developmental environments. We discuss possible explanations for differences in response between progesterone and estradiol, as well as broader implications of our findings. Am. J. Hum. Biol., 2008. © 2007 Wiley-Liss, Inc. [source] Influence of the mother's reproductive state on the hormonal status of daughters in marmosets (Callithrix kuhlii)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 1 2004Alyssa M. Puffer Abstract Behavioral and endocrine suppression of reproduction in subordinate females produces the high reproductive skew that characterizes callitrichid primate mating systems. Snowdon et al. [American Journal of Primatology 31:11,21, 1993] reported that the eldest daughters in tamarin families exhibit further endocrinological suppression immediately following the birth of siblings, and suggested that dominant females exert greater control over subordinate endocrinology during this energetically challenging phase of reproduction. We monitored the endocrine status of five Wied's black tufted-ear marmoset daughters before and after their mother delivered infants by measuring concentrations of urinary estradiol (E2), pregnanediol glucuronide (PdG), testosterone (T), and cortisol (CORT). Samples were collected from marmoset daughters 4 weeks prior to and 9 weeks following three consecutive sibling-litter births when the daughters were prepubertal (M=6.1 months of age), peripubertal (M=11.9 months), and postpubertal (M=17.6 months). The birth of infants was associated with reduced ovarian steroid excretion only in the prepubertal daughters. In contrast, ovarian steroid levels tended to increase in the postpubertal daughters. Urinary E2 and T levels in the postpubertal daughters were 73.8% and 37.6% higher, respectively, in the 3 weeks following the birth of infants, relative to prepartum levels. In addition, peak urinary PdG concentrations in peri- and postpubertal daughters were equivalent to luteal phase concentrations in nonpregnant, breeding adult females, and all of the peri- and postpubertal daughters showed clear ovulatory cycles. Cortisol excretion did not change in response to the reproductive status of the mother, nor did the concentrations change across age. Our data suggest that marmoset daughters of potential breeding age are not hormonally suppressed during the mother's peripartum period or her return to fertility. These findings provide an additional example of species diversity in the social regulation of reproduction in callitrichid primates. Am. J. Primatol. 64:29,37, 2004. © 2004 Wiley-Liss, Inc. [source] | ||||||||||