-
Research in Veterinary Science Dec 2022Artificial insemination (AI) is the most important biotechnology in pig reproduction. To achieve the best possible fertility results, appropriate timing of the...
Artificial insemination (AI) is the most important biotechnology in pig reproduction. To achieve the best possible fertility results, appropriate timing of the insemination is essential. The optimal time for AI is 12 h before to 4 h after ovulation. This time-frame, unlike in estrus, is not recognizable through external indicators. It would, therefore, be beneficial to find simple and economical methods that support manual estrus checks and are able to determine the time of ovulation more accurately. On this basis, starting 80 h after weaning, 14 DanBred sows (parity: 5.2 ± 2.4) were checked for ovulation via ultrasound scans every 8 h over a period of 72 h. Additionally, rectal fecal samples were taken and analyzed for their estrogen concentration to assess possible relations to ovulation time. On average, sows ovulated 121 ± 10 h after weaning and 16 ± 9 h after onset of heat. There was a prominent drop in fecal estrogen levels 4 h before ovulation when compared to almost all other points in time (before ovulation: 20 h (P = 0.056), 12 h (P = 0.006); after ovulation: 4 h and 12 h (P < 0.001)). There are, however, significant differences in the sow-individual fecal estrogen concentrations for which several influencing factors must be considered.
Topics: Animals; Estrogens; Estrus; Female; Insemination, Artificial; Ovulation; Pregnancy; Reproduction; Swine; Weaning
PubMed: 35777284
DOI: 10.1016/j.rvsc.2022.05.005 -
Biological Reviews of the Cambridge... Jun 2021The ovule and its developmental successor, the seed, together represent a highly characteristic feature of seed plants that has strongly enhanced the reproductive and... (Review)
Review
The ovule and its developmental successor, the seed, together represent a highly characteristic feature of seed plants that has strongly enhanced the reproductive and dispersal potential of this diverse group of taxa. Ovules encompass multiple tissues that perform various roles within a highly constrained space, requiring a complex cascade of genes that generate localized cell proliferation and programmed cell death during different developmental stages. Many heritable morphological differences among lineages reflect relative displacement of these tissues, but others, such as the second (outer) integuments of angiosperms and Gnetales, represent novel and apparently profound and independent innovations. Recent studies, mostly on model taxa, have considerably enhanced our understanding of gene expression in the ovule. However, understanding its evolutionary history requires a comparative and phylogenetic approach that is problematic when comparing extant angiosperms not only with phylogenetically distant extant gymnosperms but also with taxa known only from fossils. This paper reviews ovule characters across a phylogenetically broad range of seed plants in a dynamic developmental context. It discusses both well-established and recent theories of ovule and seed evolution and highlights potential gaps in comparative data that will usefully enhance our understanding of evolutionary transitions and developmental mechanisms.
Topics: Fossils; Magnoliopsida; Ovule; Phylogeny; Seeds
PubMed: 33432779
DOI: 10.1111/brv.12684 -
Methods in Molecular Biology (Clifton,... 2021Doubled haploid (DH) technology is very advantageous in plant breeding. This technique is beneficial for reducing the time required to obtain pure lines and contributes...
Doubled haploid (DH) technology is very advantageous in plant breeding. This technique is beneficial for reducing the time required to obtain pure lines and contributes to the selection efficiency. Using this technique, 100% homozygosity can be achieved in a single generation, while the development of stable lines using the traditional self-pollination method takes from 6 to 8 years. It has long been used in diverse crops including cucurbits. DHs can be obtained via parthenogenesis (pollination mostly with irradiated pollen), gynogenesis (in vitro culture of ovules and ovaries), and androgenesis (in vitro culture of microspores and anthers). All these methods have been used for over 30 years to develop haploid and DH lines in cucurbit crops. Nowadays, many researchers benefit from these techniques routinely. However, there are still many limits for using DH technology in watermelon breeding programmes. The number of developed DH lines is still very low.In this chapter, we present a protocol based on the different studies on haploids and DHs induced in watermelon through irradiated pollen technique, unfertilized ovule/ovary culture and anther/microspore culture. According to the results of all these studies, it is crucial to develop an efficient protocol for haploid embryo induction to enhance the frequency of obtaining haploid embryos in watermelon.
Topics: Citrullus; Crops, Agricultural; Haploidy; Ovule; Parthenogenesis; Plant Breeding; Pollen; Pollination
PubMed: 34270065
DOI: 10.1007/978-1-0716-1331-3_6 -
Medicina (Kaunas, Lithuania) Aug 2023: The Quantum Menstrual Health Monitoring Study will measure four key reproductive hormones in the urine (follicle-stimulating hormone, FSH; estrone-3-glucuronide, E3G;...
: The Quantum Menstrual Health Monitoring Study will measure four key reproductive hormones in the urine (follicle-stimulating hormone, FSH; estrone-3-glucuronide, E3G; luteinizing hormone, LH; and pregnanediol glucuronide, PDG) to characterize patterns that predict and confirm ovulation, referenced to serum hormones and the gold standard of the ultrasound day of ovulation in participants with regular cycles. These normal cycles will provide a reference for comparison to irregular cycles in subjects with polycystic ovarian syndrome (PCOS) and athletes. : Participants will track their menstrual cycles for 3 months and be provided with an at-home urine hormone monitor (Mira monitor) to predict ovulation. The day of ovulation will be confirmed with serial ultrasounds completed in a community clinic. Urine results will be compared to serum hormone values. Other markers of menstrual health, such as bleeding patterns and temperature changes, will be determined using a customized app. Three groups will be recruited. Group 1 will include those with consistent regular cycle lengths (between 24-38 days), and will be compared to two groups with irregular cycle lengths (with increased cycle length variability and longer cycles). Group 2 will include those with polycystic ovarian syndrome (PCOS) with irregular cycles and Group 3 will include individuals participating in high levels of exercise with irregular cycles. : The Mira monitor quantitative urine hormone pattern will accurately correlate with serum hormonal levels and will predict (with LH) and confirm (with PDG) the ultrasound day of ovulation in those with regular cycles as well as those with irregular cycles. : Once the ultrasound validation is complete, tools like the Mira monitor with a customized app may become a new standard for at-home and remote clinical monitoring of the menstrual cycle without having to use labor-intensive follicular-tracking ultrasound or follow serum hormone changes. : Precision monitoring of the menstrual cycle is expected to impact individuals who want to increase their menstrual health literacy and guide decisions about fertility.
Topics: Female; Humans; Polycystic Ovary Syndrome; Menstrual Cycle; Luteinizing Hormone; Ovulation; Follicle Stimulating Hormone
PubMed: 37763632
DOI: 10.3390/medicina59091513 -
Contraception Jun 2022To investigate the effect of different oral dosages of levonorgestrel (LNG) on ovarian activity and to identify the lowest dosage at which no ovulation occurred....
OBJECTIVES
To investigate the effect of different oral dosages of levonorgestrel (LNG) on ovarian activity and to identify the lowest dosage at which no ovulation occurred. Secondary objectives were to assess return of ovulation after stopping treatment, bleeding pattern, pharmacokinetic (PK) parameters and safety and tolerability.
STUDY DESIGN
A parallel-group study with adaptive design was performed in 90 healthy women with proven ovulatory cycles. Investigated dosages were LNG 0.095, 0.115 and 0.135 mg per day. Measurements of follicular growth and estradiol (E) and progesterone concentrations were performed every 3 (±1) days during a 56-day treatment and a post-treatment period. Follicle-stimulating hormone and luteinizing hormone concentrations and multiple-dose PK parameters were determined during treatment.
RESULTS
Two normal ovulations occurred in the LNG 0.095 mg group, none in the higher dose groups. Most subjects had active follicle-like structures without ovulation (Hoogland-Skouby scores 4). Ovarian activity was more suppressed in the highest dose group than in the other groups. Mean E concentrations were 241, 219 and 180 pmol/L during treatment with 0.095, 0.115 and 0.135 mg per day, respectively. PK results showed dose-proportionality. Most subjects ovulated during the post-treatment period.
CONCLUSION
LNG 0.115 mg per day was the lowest effective dosage for consistent ovulation inhibition. All investigated dosages were safe and well-tolerated, and mean E concentrations were sufficient for prevention of hypoestrogenic side effects.
IMPLICATIONS
Marketed progestogen-only pills (POP) containing 0.03 mg LNG do not consistently inhibit ovulation. Increasing the dosage to 0.115 mg or 0.135 mg per day, resulting in consistent ovulation inhibition, may improve the contraceptive efficacy of the LNG-POP.
Topics: Estradiol; Female; Follicle Stimulating Hormone; Humans; Levonorgestrel; Luteinizing Hormone; Ovary; Ovulation; Ovulation Inhibition; Progesterone
PubMed: 35123981
DOI: 10.1016/j.contraception.2022.01.018 -
Plant Science : An International... Oct 2023Ovules are precursors of seeds and contain sporophytic integuments and gametophytic embryo sac. In Arabidopsis, embryo sac development requires highly synchronized... (Review)
Review
Ovules are precursors of seeds and contain sporophytic integuments and gametophytic embryo sac. In Arabidopsis, embryo sac development requires highly synchronized morphogenesis of integument such that defects in integument growth often accompanies with a block in megagametogenesis, indicating that integument instructs the development of female gametophytes. In this mini review, we discuss signaling pathways through which integument cells mediate embryo sac development. We also propose ways to identify key signaling factors for the communication between integument and developing female gametophyte.
Topics: Ovule; Signal Transduction; Arabidopsis; Seeds; Arabidopsis Proteins
PubMed: 37574141
DOI: 10.1016/j.plantsci.2023.111829 -
Nutrients Mar 2024The role of minerals in female fertility, particularly in relation to the menstrual cycle, presents a complex area of study that underscores the interplay between... (Review)
Review
The role of minerals in female fertility, particularly in relation to the menstrual cycle, presents a complex area of study that underscores the interplay between nutrition and reproductive health. This narrative review aims to elucidate the impacts of minerals on key aspects of the reproductive system: hormonal regulation, ovarian function and ovulation, endometrial health, and oxidative stress. Despite the attention given to specific micronutrients in relation to reproductive disorders, there is a noticeable absence of a comprehensive review focusing on the impact of minerals throughout the menstrual cycle on female fertility. This narrative review aims to address this gap by examining the influence of minerals on reproductive health. Each mineral's contribution is explored in detail to provide a clearer picture of its importance in supporting female fertility. This comprehensive analysis not only enhances our knowledge of reproductive health but also offers clinicians valuable insights into potential therapeutic strategies and the recommended intake of minerals to promote female reproductive well-being, considering the menstrual cycle. This review stands as the first to offer such a detailed examination of minerals in the context of the menstrual cycle, aiming to elevate the understanding of their critical role in female fertility and reproductive health.
Topics: Female; Humans; Menstrual Cycle; Ovulation; Reproduction; Minerals; Knowledge
PubMed: 38613041
DOI: 10.3390/nu16071008 -
Journal of Assisted Reproduction and... Apr 2022In mammalian species an optimal fertilization window during which successful fertilization occurs. In the majority of mammals estrus marks ovulation time and coincident... (Review)
Review
In mammalian species an optimal fertilization window during which successful fertilization occurs. In the majority of mammals estrus marks ovulation time and coincident with mating, thereby allowing the synchronized meeting in the fallopian tubes, between freshly ejaculated sperm and freshly ovulated oocytes. Conversely, women do not show natural visual signs of ovulation such that fertilization can occur hours later involving an aged oocyte and freshly ejaculated spermatozoa. During this time, the oocyte undergoes a rapid degradation known as "postovulatory aging" (POA). POA may become particularly important in the human-assisted reproductive technologies, as the fertilization of retrieved mature oocytes can be delayed due to increased laboratory workload or because of unforeseeable circumstances, like the delayed availability of semen samples. This paper is an updated review of the consequences of POA, either in vivo or in vitro, on oocyte quality with particular attention to modifications caused by POA on oocyte nuclear, cytoplasmic, genomic, and epigenetic maturation, and embryo development.
Topics: Aged; Aging; Animals; Cellular Senescence; Embryonic Development; Female; Humans; Male; Mammals; Oocytes; Ovulation
PubMed: 35312936
DOI: 10.1007/s10815-022-02418-y -
Journal of Integrative Plant Biology Aug 2022Seed is the offspring of angiosperms. Plants produce large numbers of seeds to ensure effective reproduction and survival in varying environments. Ovule is a... (Review)
Review
Seed is the offspring of angiosperms. Plants produce large numbers of seeds to ensure effective reproduction and survival in varying environments. Ovule is a fundamentally important organ and is the precursor of the seed. In Arabidopsis and other plants characterized by multi-ovulate ovaries, ovule initiation determines the maximal ovule number, thus greatly affecting seed number per fruit and seed yield. Investigating the regulatory mechanism of ovule initiation has both scientific and economic significance. However, the genetic and molecular basis underlying ovule initiation remains unclear due to technological limitations. Very recently, rules governing the multiple ovules initiation from one placenta have been identified, the individual functions and crosstalk of phytohormones in regulating ovule initiation have been further characterized, and new regulators of ovule boundary are reported, therefore expanding the understanding of this field. In this review, we present an overview of current knowledge in ovule initiation and summarize the significance of ovule initiation in regulating the number of plant offspring, as well as raise insights for the future study in this field that provide potential routes for the improvement of crop yield.
Topics: Arabidopsis; Arabidopsis Proteins; Ovule; Plant Growth Regulators; Seeds
PubMed: 35713236
DOI: 10.1111/jipb.13314 -
International Journal of Molecular... Mar 2021Angiosperm reproduction relies on the precise growth of the pollen tube through different pistil tissues carrying two sperm cells into the ovules' embryo sac, where they... (Review)
Review
Angiosperm reproduction relies on the precise growth of the pollen tube through different pistil tissues carrying two sperm cells into the ovules' embryo sac, where they fuse with the egg and the central cell to accomplish double fertilization and ultimately initiate seed development. A network of intrinsic and tightly regulated communication and signaling cascades, which mediate continuous interactions between the pollen tube and the sporophytic and gametophytic female tissues, ensures the fast and meticulous growth of pollen tubes along the pistil, until it reaches the ovule embryo sac. Most of the pollen tube growth occurs in a specialized tissue-the transmitting tract-connecting the stigma, the style, and the ovary. This tissue is composed of highly secretory cells responsible for producing an extensive extracellular matrix. This multifaceted matrix is proposed to support and provide nutrition and adhesion for pollen tube growth and guidance. Insights pertaining to the mechanisms that underlie these processes remain sparse due to the difficulty of accessing and manipulating the female sporophytic tissues enclosed in the pistil. Here, we summarize the current knowledge on this key step of reproduction in flowering plants with special emphasis on the female transmitting tract tissue.
Topics: Extracellular Matrix; Fertilization; Flowers; Magnoliopsida; Ovule; Plant Proteins; Pollen Tube; Seeds; Signal Transduction
PubMed: 33807566
DOI: 10.3390/ijms22052603