• The primary oocyte turns into a secondary oocyte in mature ovarian follicles. (wikipedia.org)
  • [2] It is developed from the primary oocyte by maturation. (wikipedia.org)
  • This protocol consists of a culture method that can be mainly divided into four periods: primordial germ cell-like cell (PGCLC) derivation, primary oocyte differentiation (in vitro differentiation: IVDi), oocyte growth to germinal vesicle (GV) oocytes (in vitro growth: IVG) and oocyte maturation (in vitro maturation: IVM). (researchsquare.com)
  • The nucleus of such an oocyte is called a germinal vesicle (see picture). (wikipedia.org)
  • Germinal vesicle breakdown (GVBD) occurs during oocyte meiotic maturation, a period when transcriptional processes are virtually inactive. (biomedcentral.com)
  • Following germinal vesicle break down (GVBD) the oocyte is transcriptionally quiescent until fertilization and activation of the embryonic genome, occurring at the four-cell stage of development in the pig [ 9 ]. (biomedcentral.com)
  • For several primary oocytes that complete meiosis I each month, only one or a few functional oocyte, the dominant follicles, completes maturation and undergoes ovulation. (wikipedia.org)
  • These protease-induced decreases in IGFBP-4 and -5 likely cause increased levels of bioavailable (or free) IGFs that stimulate steroidogenesis and mitogenesis in developing dominant follicles, which ultimately prepare the follicle(s) and oocyte(s) for successful ovulation and fertilization. (bioone.org)
  • Ovaries from abattoirs are grouped into four categories: ovaries without corpus luteum and dominant follicles (-CL and -FD), without corpus luteum and with dominant follicles (-CL and + FD), with corpus luteum and without dominant follicle (+ CL and -FD), and with corpus luteum and dominant follicles (+ CL and + FD). (ifory.id)
  • Poor in vitro embryo development is a major obstacle in porcine assisted reproduction. (mdpi.com)
  • In the current study, we utilized modified Spirulina maxima pectin nanoparticles as a supplement to improve porcine in vitro maturation medium. (mdpi.com)
  • Oocytes were collected from aspirated porcine tertiary follicles. (biomedcentral.com)
  • Upon fertilization by sperm, the secondary oocyte continues the second part of meiosis and becomes a zygote. (wikipedia.org)
  • Quality control in human in vitro fertilization. (shengsci.com)
  • The implementation of suitable quality control (QC) is not only required for the accreditation of a human in vitro fertilization (IVF) laboratory, but is also fundamental to its success. (shengsci.com)
  • This study aims to determine the ability of in vitro embryo cleavage of Bali cattle 48 hours after the fertilization process based on different ovarian reproductive status. (ifory.id)
  • After maturation, in vitro fertilization was carried out using TALP media with a final concentration of spermatozoa 1.5 x 106 spermatozoa/ml. (ifory.id)
  • Oocytes 5-6 after fertilization were washed 3 times using CR1aa media then cultured in 5% CO2 incubator, temperature 38.5 °C for 48 hours. (ifory.id)
  • SECM technique may be a valuable tool for accurately assessing the quality of embryos and thereby contribute to improving outcomes associated with assisted reproduction, including human in vitro fertilization. (bioone.org)
  • Assisted reproductive techniques for canines: preservation of genetic material in domestic dogs [3] "Assisted reproductive techniques (ARTs), such as artificial insemination, in vitro fertilization, and cryopreservation of gametes/zygotes, have been developed to improve breeding and reproduction of livestock and for the treatment of human infertility. (edu.au)
  • Despite considerable technological advancements, polyspermy remains a significant challenge in in-vitro fertilization (IVF) procedures in pigs, disrupting normal embryonic development. (e-jarb.org)
  • Mammalian oocytes are maintained in meiotic prophase arrest for a very long time-months in mice, years in humans. (wikipedia.org)
  • Mammalian ovaries are endowed with a huge number of small oocytes (primordial oocytes) in primordial follicles. (go.jp)
  • Maturation of the mammalian oocyte is a complex process involving internal checkpoints and bidirectional communication with the surrounding cumulus cells. (biomedcentral.com)
  • An ovarian follicle is a roughly spheroid cellular aggregation set found in the ovaries. (wikipedia.org)
  • In mammals , the first part of oogenesis starts in the germinal epithelium , which gives rise to the development of ovarian follicles , the functional unit of the ovary . (wikipedia.org)
  • Throughout a female's reproductive lifespan, the ovaries undergo continual structural changes that are crucial for the maturation of ovarian follicles and the production of sex steroid hormones. (mdpi.com)
  • These structures are periodically initiated to grow and develop, culminating in ovulation of usually a single competent oocyte in humans. (wikipedia.org)
  • As follicles grow, they acquire receptors for luteinizing hormone, a pituitary hormone that reinitiates meiosis in the oocyte and causes ovulation of a fertilizable egg. (wikipedia.org)
  • The application of reproductive biotechnology tools such as estrus synchronization (ES), artificial insemination (AI), embryo transfer (ET) through multiple ovulation and in vivo collection of embryos, in-vitro embryo production (IVEP) and cryopreservation, somatic cell nuclear transfer (SCNT) to produce the desired breed and sex of animal, and other reproductive biotechnologies that enhances reproduction potential are important innovations that can address specific needs and purpose for animal reproduction. (ifory.id)
  • Synchronization of estrus followed by induction of ovulation are basic techniques in all embryo transfer programs. (biomedcentral.com)
  • Since the development of in vitro embryo production in cattle, different supplements have been added to culture media to support embryo development, with serum being the most popular. (biomedcentral.com)
  • Analysis of global gene expression in bovine embryos produced under different conditions can provide valuable information to optimize culture media for in vitro embryo production. (biomedcentral.com)
  • We used RNA sequencing to examine the effect of in vitro embryo production, in either serum-containing or serum-free media, on the global gene expression pattern of individual bovine blastocysts. (biomedcentral.com)
  • Since the initial development of in vitro embryo production, the technique has been applied successfully to many species for clinical, commercial, and research purposes. (biomedcentral.com)
  • This study was conducted to evaluate in vivo and in vitro development of in vitro-matured equine oocytes fertilized by intracytoplasmic sperm injection. (bioone.org)
  • In vivo development was assessed after transfer of injected oocytes to the oviducts of recipient mares. (bioone.org)
  • We have recently established a novel culture system in which mouse pluripotent stem cells differentiate to mature oocytes in a manner similar to oogenesis in vivo. (researchsquare.com)
  • The synchronization and ovulatory responses of Sangsari cross bred ewes and metabolism of energy substrates in 8-cell stage embryos to hatched blastocysts stage produced in vitro or in vivo were investigated. (biomedcentral.com)
  • While the pattern of oxidation was similar among in vitro and in vivo derived embryos, a low pyruvate to lactate ratio was the preferred substrate of embryos derived in vitro . (biomedcentral.com)
  • The production of CO2 from glucose by sheep embryos has been determined[ 3 ] and results have indicated that little glucose is utilized by the embryos of sheep and that blastocysts derived from oocytes, matured and fertilized in vitro , oxidized glucose at a lower rate than those developed in vivo . (biomedcentral.com)
  • A small number of primordial oocytes start to grow, while others remain quiescent. (go.jp)
  • In this review, we summarize the results regarding the activation of primordial oocytes in neonatal and adult ovaries of different species and propose a model in which ovaries of neonatal mammals contain a mixed population of both quiescent and activated primordial oocytes, while almost all primordial oocytes are quiescent in adult females. (go.jp)
  • These quiescent primordial oocytes are activated, perhaps by certain mechanisms involving the interaction between stimulatory and inhibitory factors, to enter the growth phase. (go.jp)
  • Oocytes were collected from slaughterhouse-derived ovaries, matured in vitro, and injected with frozen-thawed stallion sperm. (bioone.org)
  • 4 Of note, PGCLCs gave rise to sperm and oocytes by transplantation into neonatal testes and adult ovaries, respectively, 4,5 which means that PGCLCs have the potential to give rise to functional gametes. (researchsquare.com)
  • in-vitro -matured oocytes were co-incubated with sperm according to a modified two-step culture system. (e-jarb.org)
  • In the first experiment, oocytes were briefly co-incubated with sperm, washed in IVF medium, and then moved to fresh IVF medium for 5 or 6 h. (e-jarb.org)
  • In experiment 2, oocytes were inseminated with sperm separated by Pecroll treatment. (e-jarb.org)
  • For in vitro culture of follicles, there are various techniques to optimize the growth of follicles, including the use of defined media, growth factors and three-dimensional extracellular matrix support. (wikipedia.org)
  • After beginning the meiotic process, the oogonia (now called primary oocytes) can no longer replicate. (wikipedia.org)
  • However, as the oocyte grows, these proteins are synthesized, and meiotic arrest becomes dependent on cyclic AMP . (wikipedia.org)
  • Maintenance of meiotic arrest also depends on the presence of a multilayered complex of cells, known as a follicle, that surrounds the oocyte. (wikipedia.org)
  • In the oocyte, cyclic GMP prevents the breakdown of cyclic AMP by the phosphodiesterase PDE3, and thus maintains meiotic arrest. (wikipedia.org)
  • Inhibition of nuclear meiotic maturation via IBMX significantly increased MIR21 and decreased its target, PDCD4. (biomedcentral.com)
  • Our results indicate MIR21 is active and important during meiotic maturation of the oocyte. (biomedcentral.com)
  • The oocyte must maintain arrest at the diplotene stage until meiotic resumption occurs. (biomedcentral.com)
  • Of particular interest is understanding the role of non-coding RNA in regulating meiotic checkpoints in the oocyte, particularly that of microRNA-21 (MIR21). (biomedcentral.com)
  • Little is known about the mechanism regulating the activation of primordial oocytes. (go.jp)
  • We think that primordial oocytes in adult mammals are different from those in neonatal mammals. (go.jp)
  • The dormancy of primordial oocytes may be required to reserve the non-growing oocyte pool for the long reproductive life in mammals. (go.jp)
  • FOXO3 is considered one of the molecules responsible for the dormancy of primordial oocytes in adult ovaries. (go.jp)
  • In this paper, we describe a scanning electrochemical microscopy (SECM) technique that is a non-invasive and sensitive method for measuring oxygen consumption by individual embryos. (bioone.org)
  • Surgical embryo recovery was performed on Days 4 and 6 after onset of estrus (Day 0) and recovered embryos were subjected to comparative metabolism studies with in vitro derived embryos at the same stage of development. (biomedcentral.com)
  • Along with polyspermy, the suboptimal quality of IVF-derived pig embryos poses another challenge that needs to be addressed for in vitro production systems. (e-jarb.org)
  • Importantly, in vitro production in the presence of serum appeared to have a different impact on the embryos according to their sex, with male embryos having three times more genes differentially expressed than their female counterparts (1283 vs. 456). (biomedcentral.com)
  • Male embryos appeared to be most affected by suboptimal in vitro culture, i.e. in the presence of serum. (biomedcentral.com)
  • Each of them contains a single oocyte (immature ovum or egg cell). (wikipedia.org)
  • Once a month, one of the ovaries releases a mature egg (ovum), known as an oocyte. (wikipedia.org)
  • Diagram showing the reduction in number of the chromosomes in the process of maturation of the ovum . (wikipedia.org)
  • oocytogenesis , ootidogenesis , and finally maturation to form an ovum (oogenesis proper). (wikipedia.org)
  • Oogenesis incorporates a unique sequence of differentiation processes, during which biologically significant events such as meiosis and oocyte growth are orchestrated with communication to surrounding somatic cells. (researchsquare.com)
  • In plants, polytene chromosomes have been observed in only a few species, and seemed to be restricted to ovary and immature seed tissues, e.g., in Phaseolus coccineus and P. vulgaris (Nagl, 1981), until relatively recently, when they were observed in the cells of the anther tapetum of Vigna unguiculata (Guerra and Carvalheira, 1994) and of some Phaseolus species (Carvalheira and Guerra, 1994). (scielo.br)
  • Oogenesis starts with the process of developing primary oocytes, which occurs via the transformation of oogonia into primary oocytes , a process called oocytogenesis . (wikipedia.org)
  • If trade-offs exist between somatic growth and reproduction for this species, a reduction in the physiological condition of swamp fish should be accompanied by reduced development of reproductive tissue (gonad mass), as found in other fish (Wu et al. (researchgate.net)
  • To characterize the effect of artificially increasing MIR21 on oocyte competence without inhibiting GVBD, a MIR21 mimic, scrambled microRNA negative control, or nuclease free water was micro-injected into denuded oocytes at 21 h of IVM. (biomedcentral.com)
  • Oocyte meiosis, important to all animal life cycles yet unlike all other instances of animal cell division, occurs completely without the aid of spindle -coordinating centrosomes . (wikipedia.org)
  • Removal of the oocyte from the follicle causes meiosis to progress in the oocyte. (wikipedia.org)
  • Through somatic cell nuclear transfer, we finally obtain transgenic cattle with increased resistance to tuberculosis. (biomedcentral.com)
  • Biomechanical forces and signals operating in the ovary during folliculogenesis and their dysregulation: implications for fertility. (ivi-rmainnovation.com)
  • In experiment 3, fertilized oocytes were cultured in 25 μL microdroplets (10 gametes/drop) or 500 μL (100 gametes/well) of culture medium in 4-well plates. (e-jarb.org)
  • PMPCB encodes the catalytic subunit of the essential mitochondrial processing protease (MPP), which is required for maturation of the majority of mitochondrial precursor proteins. (regenerativemedicine.net)
  • Reproductive outcomes of oocyte donation in patients with uterine Müllerian anomalies. (ivi-rmainnovation.com)
  • Whether the hormonal control of PAPP-A production/activity by the ovary differs between monotocous and polytocous animals will require further study. (bioone.org)
  • The pathways affected by in vitro production differed depending on the type of supplementation. (biomedcentral.com)
  • Here, we established a culture system in which the entire process of oogenesis is reconstituted in a dish, yielding in vitro-generated oocytes that are capable of full-term development to healthy pups. (researchsquare.com)
  • Once gametogonia enter the gonadal ridge, however, they attempt to associate with these somatic cells. (wikipedia.org)
  • Endometrial Cells Acutely Exposed to Phthalates In Vitro Do Not Phenocopy Endometriosis. (ivi-rmainnovation.com)
  • Oocyte arrest at the diplotene stage is maintained in part through the activity of phosphodiesterase enzymes that catalyze the hydrolysis of cyclic adenosine monophosphate (cAMP) into AMP [ 1 , 2 ]. (biomedcentral.com)
  • The large volume of medium significantly reduced the number of dead oocytes and increased the rate of blastocyst formation compared to the small volume. (e-jarb.org)
  • The inability to transcribe mRNA during this stage of development and the probable necessity for post-transcriptional gene regulation (PTGR) suggests an important role for non-coding RNA in the maturing oocyte. (biomedcentral.com)
  • this reduction may be due to an increase in testosterone levels and testosterone to estradiol ratio, which will affect gonad maturation (Friesen et al. (researchgate.net)
  • Injection of a MIR21 mimic increased oocyte maturation rate. (biomedcentral.com)
  • Percoll treatment increased the rate of oocyte penetration and blastocyst formation compared to the control. (e-jarb.org)
  • Relative abundance of mature MIR21 was quantified at 0, 8, 16, 24, 32, and 42 h of in vitro (IVM) with or without treatment with 3-isobutyl-1-methylxanthine (IBMX). (biomedcentral.com)
  • The adenylyl cyclase is kept active by a constitutively active G-protein-coupled receptor known as GPR3 and a G-protein, Gs, also present in the oocyte membrane. (wikipedia.org)
  • In vitro effects of PCBs and OH-PCBs on the basal and dexamethasone-modified thyroid hormone metabolism in chicken liver. (krakow.pl)
  • The ovaries are responsible for regulating reproduction and endocrine function. (mdpi.com)
  • In humans, oocytes are established in the ovary before birth and may lie dormant awaiting initiation for up to 50 years. (wikipedia.org)