What to do now? How women with breast cancer make fertility preservation decisions.

PubMed

Snyder, Karrie Ann; Tate, Alexandra Lee

2013-07-01

There has been increased attention paid to cancer-related infertility and fertility preservation. However, how cancer patients decide whether or not to pursue fertility preservation has not been fully examined. The data come from 34 interviews with women in the USA diagnosed with breast cancer prior to 40 years of age who contemplated fertility preservation prior to cancer treatment. Fully transcribed interviews were coded through a three-staged inductive process. Three sets of factors that shaped the decision-making process of the respondents regarding fertility preservation treatment options were identified: perceived benefits (e.g. ability to use 'younger' eggs in the future), inhibiting concerns (e.g. success rates) and influential relationships (e.g. physicians, parents and partners). Respondents saw their main fertility preservation decision as choosing whether or not to pursue egg/embryo banking. The decision-making process was complicated and included both health-related and personal considerations, with many respondents reporting a lack of support services for fertility issues. Findings suggest that greater attention needs to be placed on presenting patients with a wider range of options. Those who counsel patients regarding fertility preservation decisions should be aware of the influence of relationship dynamics, broader health care concerns, and fertility histories on these decisions. KEY MESSAGE POINTS: While fertility preservation has garnered greater attention, less is known about how cancer patients make fertility preservation decisions. Despite the range of choices for fertility preservation, respondents identified egg/embryo banking as their primary option. Many factors outside of cancer concerns inhibit and facilitate fertility preservation decisions including fertility history and family relationship dynamics.

Zinc sparks induce physiochemical changes in the egg zona pellucida that prevent polyspermy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Que, Emily L.; Duncan, Francesca E.; Bayer, Amanda R.

During fertilization or chemically-induced egg activation, the mouse egg releases billions of zinc atoms in brief bursts known as ‘zinc sparks.’ The zona pellucida (ZP), a glycoprotein matrix surrounding the egg, is the first structure zinc ions encounter as they diffuse away from the plasma membrane. Following fertilization, the ZP undergoes changes described as ‘hardening’, which prevent multiple sperm from fertilizing the egg and thereby establish a block to polyspermy. A major event in zona hardening is cleavage of ZP2 proteins by ovastacin; however, the overall physiochemical changes contributing to zona hardening are not well understood. Using x-ray fluorescence microscopy,more » transmission and scanning electron microscopy, and biological function assays, we tested the hypothesis that zinc release contributes to ZP hardening. We found that the zinc content in the ZP increases by 300% following activation and that zinc exposure modulates the architecture of the ZP matrix. Importantly, zinc-induced structural changes of the ZP have a direct biological consequence; namely, they reduce the ability of sperm to bind to the ZP. These results provide a paradigm-shifting model in which fertilization-induced zinc sparks contribute to the polyspermy block by altering conformations of the ZP matrix. Finally, this adds a previously unrecognized factor, namely zinc, to the process of ZP hardening.« less

Zinc sparks induce physiochemical changes in the egg zona pellucida that prevent polyspermy

DOE PAGES

Que, Emily L.; Duncan, Francesca E.; Bayer, Amanda R.; ...

2017-01-19

During fertilization or chemically-induced egg activation, the mouse egg releases billions of zinc atoms in brief bursts known as ‘zinc sparks.’ The zona pellucida (ZP), a glycoprotein matrix surrounding the egg, is the first structure zinc ions encounter as they diffuse away from the plasma membrane. Following fertilization, the ZP undergoes changes described as ‘hardening’, which prevent multiple sperm from fertilizing the egg and thereby establish a block to polyspermy. A major event in zona hardening is cleavage of ZP2 proteins by ovastacin; however, the overall physiochemical changes contributing to zona hardening are not well understood. Using x-ray fluorescence microscopy,more » transmission and scanning electron microscopy, and biological function assays, we tested the hypothesis that zinc release contributes to ZP hardening. We found that the zinc content in the ZP increases by 300% following activation and that zinc exposure modulates the architecture of the ZP matrix. Importantly, zinc-induced structural changes of the ZP have a direct biological consequence; namely, they reduce the ability of sperm to bind to the ZP. These results provide a paradigm-shifting model in which fertilization-induced zinc sparks contribute to the polyspermy block by altering conformations of the ZP matrix. Finally, this adds a previously unrecognized factor, namely zinc, to the process of ZP hardening.« less

Hydrodynamic context for considering turbulence impacts on external fertilization.

PubMed

Gaylord, Brian

2008-06-01

Wave-swept shores in the marine environment are characterized by turbulent water motion. This turbulence influences external fertilization in benthic organisms by diluting gametes and producing hydrodynamic shear that is believed to have the capacity to disrupt egg-sperm interaction. However, although turbulence levels associated with decreases in fertilization due to this latter process (shear) have been identified in the laboratory, estimates of the intensities of turbulence in intertidal habitats have been based primarily on scaling arguments of limited precision and unknown accuracy. In the present study, values of energy dissipation rate (a standard measure of the strength of turbulence) were determined for three locations in the surf zone of a rocky shore. These measurements suggest a potential correspondence between threshold levels of turbulence that impair the ability of sperm to fertilize eggs, and actual intensities of turbulence arising in nature.

9 CFR 93.905 - Declaration and other documents for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2010 CFR

2010-01-01

... live fish, fertilized eggs, and gametes. 93.905 Section 93.905 Animals and Animal Products ANIMAL AND... for live fish, fertilized eggs, and gametes. (a) For all live fish, fertilized eggs, and gametes... fish, fertilized eggs, or gametes, the number, species, and the purpose of the importation, the name of...

9 CFR 93.905 - Declaration and other documents for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2011 CFR

2011-01-01

... live fish, fertilized eggs, and gametes. 93.905 Section 93.905 Animals and Animal Products ANIMAL AND... for live fish, fertilized eggs, and gametes. (a) For all live fish, fertilized eggs, and gametes... fish, fertilized eggs, or gametes, the number, species, and the purpose of the importation, the name of...

Ovum donation: examining the new Israeli law.

PubMed

Gruenbaum, Benjamin F; Pinchover, Zachary S; Lunenfeld, Eitan; Jotkowitz, Alan

2011-11-01

Ovum donation affords countless couples that under natural circumstances would not be able to produce offspring the ability to carry out natural pregnancies. With advancements in biotechnology including egg collection and in vitro fertilization (IVF), physicians can now successfully implant fertilized embryos. Due to Israel's tremendous involvement in IVF for its own citizens, the national laws that govern egg donation are of great importance. On September 5th 2010, the Israeli Parliament (Knesset) passed a law that allows young women between the ages of 21 and 35 to donate their eggs for paid financial compensation. The new law allows infertile women between the ages of 18 and 54 to request egg donation and IVF, which will partially be covered under state insurance plans. This article provides a description of the new Israeli law regulating ovum donation and the practical, moral and ethical debate surrounding the new system. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

DNA repair efficiency in germ cells and early mouse embryos and consequences for radiation-induced transgenerational genomic damage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marchetti, Francesco; Wyrobek, Andrew J.

Exposure to ionizing radiation and other environmental agents can affect the genomic integrity of germ cells and induce adverse health effects in the progeny. Efficient DNA repair during gametogenesis and the early embryonic cycles after fertilization is critical for preventing transmission of DNA damage to the progeny and relies on maternal factors stored in the egg before fertilization. The ability of the maternal repair machinery to repair DNA damage in both parental genomes in the fertilizing egg is especially crucial for the fertilizing male genome that has not experienced a DNA repair-competent cellular environment for several weeks prior to fertilization.more » During the DNA repair-deficient period of spermatogenesis, DNA lesions may accumulate in sperm and be carried into the egg where, if not properly repaired, could result in the formation of heritable chromosomal aberrations or mutations and associated birth defects. Studies with female mice deficient in specific DNA repair genes have shown that: (i) cell cycle checkpoints are activated in the fertilized egg by DNA damage carried by the sperm; and (ii) the maternal genotype plays a major role in determining the efficiency of repairing genomic lesions in the fertilizing sperm and directly affect the risk for abnormal reproductive outcomes. There is also growing evidence that implicates DNA damage carried by the fertilizing gamete as a mediator of postfertilization processes that contribute to genomic instability in subsequent generations. Transgenerational genomic instability most likely involves epigenetic mechanisms or error-prone DNA repair processes in the early embryo. Maternal and embryonic DNA repair processes during the early phases of mammalian embryonic development can have far reaching consequences for the genomic integrity and health of subsequent generations.« less

9 CFR 93.904 - Health certificate for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2011 CFR

2011-01-01

..., fertilized eggs, and gametes. 93.904 Section 93.904 Animals and Animal Products ANIMAL AND PLANT HEALTH... eggs, and gametes. (a) General. All live fish, fertilized eggs, and gametes of SVC-susceptible species... from the date of issuance. The health certificate for the live fish, fertilized eggs, or gametes must...

Cryopreservation of mouse spermatozoa. I. Effect of seeding on fertilizing ability of cryopreserved spermatozoa.

PubMed

Songsasen, N; Leibo, S P

1997-11-01

To examine the effect of seeding to induce ice formation during cryopreservation on their survival, spermatozoa from B6D2F1 mice were cooled to and held at -4 degrees C for 30 min in phosphate-buffered saline (PBS) alone, in egg yolk-supplemented PBS, or in PBS with raffinose + glycerol as cryoprotective additives (CPAs). Seeding and holding spermatozoa at -4 degrees C did not affect their viability as judged by vital staining. Egg yolk protected spermatozoa against chilling injury, as cooling them to -4 degrees C in the presence of egg yolk yielded higher survivals than those cooled without egg yolk (34.4 +/- 3.4 v 9.0 +/- 1.3% in three replicates of >400 spermatozoa/replicate). To study effects of seeding on their fertilizing ability, spermatozoa in the raffinose-glycerol-egg yolk solution were frozen to -196 degrees C either without seeding or after seeding at -4 degrees C. Development of 222 oocytes into two-cell embryos after in vitro fertilization (IVF) with spermatozoa frozen without seeding was 43%; development rates of 186, 186, and 207 oocytes after IVF with spermatozoa frozen after seeding and being held at -4 degrees C for 5, 10, or 30 min were 46, 44, and 9%, respectively. In a direct comparison, after IVF with seeded or unseeded spermatozoa the respective cleavage rates into two-cell embryos were 83% of 275 oocytes and 69% of 304 oocytes, a difference that was small but significant by chi2 analysis. An additional 925 oocytes were fertilized with spermatozoa after being seeded and frozen to -196 degrees C in four separate batches of CPA solutions. Overall, after IVF with frozen sperm, 68% of those oocytes cleaved into two-cell embryos and 59% developed into 544 blastocysts. Based on these results, we concluded that embryo production by IVF seemed to be improved using spermatozoa frozen after being seeded. Mouse spermatozoa cryopreserved by the method described here are capable of fertilizing oocytes at a rather high rate. Copyright 1997 Academic Press.

In vitro fertilization experiments using sockeye salmon reveal that bigger eggs are more fertilizable under sperm limitation

PubMed Central

Macfarlane, Christopher P.; Hoysak, Drew J.; Liley, N. Robin; Gage, Matthew J.G.

2009-01-01

Although theory and widespread evidence show that the evolution of egg size is driven primarily by offspring and maternal fitness demands, an additional explanation invokes sperm limitation as a selective force that could also influence egg size optima. Levitan proposed that constraints from gamete encounter in external fertilization environments could select for enlargement of ova to increase the physical size of the fertilization target. We test this theory using in vitro fertilization experiments in an externally fertilizing fish. Sockeye salmon (Onchorhyncus nerka) females show considerable between-individual variation in ovum size, and we explored the consequences of this natural variation for the fertilization success of individual eggs under conditions of sperm limitation. By engineering consistent conditions where in vitro fertilization rate was always intermediate, we were able to compare the sizes of fertilized and unfertilized eggs across 20 fertilization replicates. After controlling for any changes in volume through incubation, results showed that successfully fertilized eggs were significantly larger than the eggs that failed to achieve fertilization. Under conditions without sperm limitation, fertility was unaffected by egg size. Our findings therefore support Levitan's theory, demonstrating empirically that some element of egg size variation could be selected by fertilization demands under sperm limitation. However, further research on sperm limitation in natural spawnings is required to assess the selective importance of these results. PMID:19364734

In vitro fertilization experiments using sockeye salmon reveal that bigger eggs are more fertilizable under sperm limitation.

PubMed

Macfarlane, Christopher P; Hoysak, Drew J; Liley, N Robin; Gage, Matthew J G

2009-07-07

Although theory and widespread evidence show that the evolution of egg size is driven primarily by offspring and maternal fitness demands, an additional explanation invokes sperm limitation as a selective force that could also influence egg size optima. Levitan proposed that constraints from gamete encounter in external fertilization environments could select for enlargement of ova to increase the physical size of the fertilization target. We test this theory using in vitro fertilization experiments in an externally fertilizing fish. Sockeye salmon (Onchorhyncus nerka) females show considerable between-individual variation in ovum size, and we explored the consequences of this natural variation for the fertilization success of individual eggs under conditions of sperm limitation. By engineering consistent conditions where in vitro fertilization rate was always intermediate, we were able to compare the sizes of fertilized and unfertilized eggs across 20 fertilization replicates. After controlling for any changes in volume through incubation, results showed that successfully fertilized eggs were significantly larger than the eggs that failed to achieve fertilization. Under conditions without sperm limitation, fertility was unaffected by egg size. Our findings therefore support Levitan's theory, demonstrating empirically that some element of egg size variation could be selected by fertilization demands under sperm limitation. However, further research on sperm limitation in natural spawnings is required to assess the selective importance of these results.

Intragenomic conflict in populations infected by Parthenogenesis Inducing Wolbachia ends with irreversible loss of sexual reproduction

PubMed Central

2010-01-01

Background The maternally inherited, bacterial symbiont, parthenogenesis inducing (PI) Wolbachia, causes females in some haplodiploid insects to produce daughters from both fertilized and unfertilized eggs. The symbionts, with their maternal inheritance, benefit from inducing the production of exclusively daughters, however the optimal sex ratio for the nuclear genome is more male-biased. Here we examine through models how an infection with PI-Wolbachia in a previously uninfected population leads to a genomic conflict between PI-Wolbachia and the nuclear genome. In most natural populations infected with PI-Wolbachia the infection has gone to fixation and sexual reproduction is impossible, specifically because the females have lost their ability to fertilize eggs, even when mated with functional males. Results The PI Wolbachia infection by itself does not interfere with the fertilization process in infected eggs, fertilized infected eggs develop into biparental infected females. Because of the increasingly female-biased sex ratio in the population during a spreading PI-Wolbachia infection, sex allocation alleles in the host that cause the production of more sons are rapidly selected. In haplodiploid species a reduced fertilization rate leads to the production of more sons. Selection for the reduced fertilization rate leads to a spread of these alleles through both the infected and uninfected population, eventually resulting in the population becoming fixed for both the PI-Wolbachia infection and the reduced fertilization rate. Fertilization rate alleles that completely interfere with fertilization ("virginity alleles") will be selected over alleles that still allow for some fertilization. This drives the final resolution of the conflict: the irreversible loss of sexual reproduction and the complete dependence of the host on its symbiont. Conclusions This study shows that dependence among organisms can evolve rapidly due to the resolution of the conflicts between cytoplasmic and nuclear genes, and without requiring a mutualism between the partners. PMID:20667099

Fertilization selection on egg and jelly-coat size in the sand dollar Dendraster excentricus.

PubMed

Levitan, D R; Irvine, S D

2001-12-01

Organisms with external fertilization are often sperm limited, and in echinoids, larger eggs have a higher probability of fertilization than smaller eggs. This difference is thought to be a result of the more frequent sperm-egg collisions experienced by larger targets. Here we report how two components of egg target size, the egg cell and jelly coat, contributed to fertilization success in a selection experiment. We used a cross-sectional analysis of correlated characters to estimate the selection gradients on egg and jelly-coat size in five replicate male pairs of the sand dollar Dendraster excentricus. Results indicated that eggs with larger cells and jelly coats were preferentially fertilized under sperm limitation in the laboratory. The selection gradients were an average of 922% steeper for egg than for jelly-coat size. The standardized selection gradients for egg and jelly-coat size were similar. Our results suggest that fertilization selection can act on both egg-cell and jelly-coat size but that an increase in egg-cell volume is much more likely to increase fertilization success than an equal change in jelly-coat volume. The strengths of the selection gradients were inversely related to the correlation of egg traits across replicate egg clutches. This result suggests the importance of replication in studies of selection of correlated characters.

CRISP1 as a novel CatSper regulator that modulates sperm motility and orientation during fertilization

PubMed Central

Ernesto, Juan I.; Weigel Muñoz, Mariana; Battistone, María A.; Vasen, Gustavo; Martínez-López, Pablo; Orta, Gerardo; Figueiras-Fierro, Dulce; De la Vega-Beltran, José L.; Moreno, Ignacio A.; Guidobaldi, Héctor A.; Giojalas, Laura; Darszon, Alberto; Cohen, Débora J.

2015-01-01

Ca2+-dependent mechanisms are critical for successful completion of fertilization. Here, we demonstrate that CRISP1, a sperm protein involved in mammalian fertilization, is also present in the female gamete and capable of modulating key sperm Ca2+ channels. Specifically, we show that CRISP1 is expressed by the cumulus cells that surround the egg and that fertilization of cumulus–oocyte complexes from CRISP1 knockout females is impaired because of a failure of sperm to penetrate the cumulus. We provide evidence that CRISP1 stimulates sperm orientation by modulating sperm hyperactivation, a vigorous motility required for penetration of the egg vestments. Moreover, patch clamping of sperm revealed that CRISP1 has the ability to regulate CatSper, the principal sperm Ca2+ channel involved in hyperactivation and essential for fertility. Given the critical role of Ca2+ for sperm motility, we propose a novel CRISP1-mediated fine-tuning mechanism to regulate sperm hyperactivation and orientation for successful penetration of the cumulus during fertilization. PMID:26416967

Parthenogenesis in mated Chinese Painted quail (Coturnix chinensis) hens decreases sperm-egg penetration and alters albumen characteristics.

PubMed

Santa Rosa, P; Parker, H M; Kiess, A S; McDaniel, C D

2016-10-15

Parthenogenesis, embryonic development without fertilization, resembles very early embryonic mortality in fertilized eggs. Also, parthenogenesis alters egg albumen characteristics in virgin Chinese Painted quail hens genetically selected for parthenogenesis (PV). When these PV hens are mated (PM), hatchability is reduced versus control mated (CM) hens that were not genetically selected for parthenogenesis. However, it is unclear if parthenogenesis, which occurs in PM hens, reduces hatchability due to infertility and altered albumen characteristics. Sperm-egg penetration (SEP) holes are indicative of true fertilization and may be useful in identifying if eggs from PM hens exhibit a decrease in fertility versus CM hens. Therefore, the objectives of this study were to determine if parthenogenesis in PM hens (1) decreases SEP, (2) alters albumen characteristics similar to parthenogenesis in eggs from PV hens, and (3) yields albumen characteristics similar to fertilized eggs containing early mortality. Daily, PV and PM eggs were collected, labeled, and incubated for 10 days, then broken out to determine the incidence of parthenogenesis and albumen characteristics. Also daily, fresh PM and CM quail eggs were macroscopically examined to determine if an egg was infertile with no embryonic development, parthenogenetic, or fertile. Each of these eggs was then microscopically examined for SEP. For both PV and PM incubated eggs, parthenogenesis decreased albumen pH, O2, and protein concentrations yet increased Ca(2+) and CO2 concentrations versus eggs with no development. For incubated PM eggs, albumen pH and O2 were lower, yet CO2 was higher for eggs containing parthenogens or early dead embryos versus infertile eggs. For SEP, fresh eggs classified as infertile or parthenogenetic from PM and CM hens had similar SEP holes but only one sixth as many SEP holes as eggs classified as fertilized. Eggs from CM hens had 3.5 times as many SEP holes as PM eggs. In conclusion, parthenogenesis that occurs in mated quail hens inhibits fertility and alters albumen characteristics similarly to parthenogenesis in unfertilized eggs and early embryonic mortality in fertilized eggs. Copyright © 2016 Elsevier Inc. All rights reserved.

9 CFR 93.903 - Import permits for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., fertilized eggs, and gametes. 93.903 Section 93.903 Animals and Animal Products ANIMAL AND PLANT HEALTH... General Provisions for Svc-Regulated Fish Species § 93.903 Import permits for live fish, fertilized eggs, and gametes. (a) Live fish, fertilized eggs, or gametes of SVC-susceptible species imported into the...

9 CFR 93.903 - Import permits for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2011 CFR

2011-01-01

..., fertilized eggs, and gametes. 93.903 Section 93.903 Animals and Animal Products ANIMAL AND PLANT HEALTH... General Provisions for Svc-Regulated Fish Species § 93.903 Import permits for live fish, fertilized eggs, and gametes. (a) Live fish, fertilized eggs, or gametes of SVC-susceptible species imported into the...

9 CFR 93.902 - Ports designated for the importation of live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2010 CFR

2010-01-01

... of live fish, fertilized eggs, and gametes. 93.902 Section 93.902 Animals and Animal Products ANIMAL... importation of live fish, fertilized eggs, and gametes. (a) The following ports are designated as ports of entry for live fish, fertilized eggs, and gametes of SVC-susceptible species imported under this subpart...

9 CFR 93.902 - Ports designated for the importation of live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2011 CFR

2011-01-01

... of live fish, fertilized eggs, and gametes. 93.902 Section 93.902 Animals and Animal Products ANIMAL... importation of live fish, fertilized eggs, and gametes. (a) The following ports are designated as ports of entry for live fish, fertilized eggs, and gametes of SVC-susceptible species imported under this subpart...

Factors controlling sperm migration through the oviduct revealed by gene-modified mouse models

PubMed Central

Fujihara, Yoshitaka; Miyata, Haruhiko; Ikawa, Masahito

2018-01-01

Mammalian fertilization is comprised of many steps including sperm survival in the uterus, sperm migration in the female reproductive tract, physiological and morphological changes to the spermatozoa, and sperm-egg interaction in the oviduct. In vitro studies have revealed essential factors for these fertilization steps for over half a century. However, the molecular mechanism of fertilization has recently been revised by the emergence of genetically modified animals. Here, we focus on essential factors for sperm fertilizing ability and describe recent advances in our knowledge of the mechanisms of mammalian fertilization, especially of sperm migration from the uterus into the oviduct. PMID:29353867

Epididymal protein CRISP1 plays different roles during the fertilization process.

PubMed

Cohen, Débora J; Maldera, Julieta A; Vasen, Gustavo; Ernesto, Juan I; Muñoz, Mariana Weigel; Battistone, María A; Cuasnicú, Patricia S

2011-01-01

Rat epididymal CRISP1, the first described member of the evolutionarily conserved Cysteine-RIch Secretory Protein (CRISP) family, is expressed in the proximal regions of the epididymis and associates with the sperm during epididymal transit. Evidence indicates the existence of 2 populations of CRISP1 in spermatozoa: a major one, loosely bound, which is released during capacitation and, therefore, proposed as a decapacitating factor; and a minor one, strongly associated with spermatozoa that remains on the cells after capacitation and is proposed to participate in gamete interaction. Originally localized to the dorsal region of capacitated sperm, CRISP1 migrates to the equatorial segment with capacitation and acrosome reaction. Consistent with these localizations, in vitro fertilization experiments support the involvement of CRISP1 in the first step of sperm-zona pellucida (ZP) interaction and subsequent gamete fusion through its interaction with egg-complementary sites. The potential roles of CRISP1 in capacitation and fertilization have been further supported by the finding that capacitated spermatozoa from CRISP1 "knockout" animals exhibit low levels of protein tyrosine phosphorylation and have an impaired ability to fertilize zona-intact and zona-free eggs in vitro. Moreover, recent evidence from mutant spermatozoa reveals that CRISP1 mediates the stage of sperm binding to the ZP. Altogether, these observations support the view that CRISP1 is a multifunctional protein playing different roles during fertilization through its different associations with and localizations on spermatozoa. We believe these results contribute to a better understanding of the molecular mechanisms involved in both the fertilization process and the acquisition of sperm-fertilizing ability that occurs during epididymal maturation.

Modification of fecundity and fertility during oogenesis by. gamma. radiation and/or ozone with a cytological analysis in the ectoparasitic wasp, Habrobracon juglandis (Ashmead)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ofuoku, E.E.

1984-01-01

In Experiment I, adult female wasps were exposed to ozone for 0, 2, 4, 6, 8, 10, 12, 16, 24, and 27 h. The results indicated that the 27 h of ozone exposure produced 100% lethality on the first day. Exposures below 27 h progressively decreased life span with increasing length of exposure. In Experiment II A, adult virgin Habrobracon females were exposed to ozone for 0, 2, 4, 6, 8, 10, 12, 16, and 24 h to determine the effects of ozone on fecundity (egg laying ability) and fertility (egg hatching ability). The results showed that ozone significantly decreasedmore » fecundity and fertility in all meiotic stages except metaphase I. In Experiment II B, adult virgin Habrobracon females were exposed to Co-60 ..gamma.. radiation. All treated wasps showed significant progressive decreases in fecundity and fertility with increases in radiation dose. In Experiment II C, adult virgin Habrobracon females were exposed to Co-60 ..gamma.. radiation, to ozone, or to combinations thereof to determine the effects of these insults on fecundity and fertility. Together or singly ozone and radiation reduced fecundity and fertility. In Experiment III, adult virgin Habrobracon females were exposed to the conditions of Experiment II C to correlate by cytological examination of the ovarioles the effects of ionizing radiation and/or ozone on the germ cells at specific meiotic stages. Results obtained from the cytological study explain the fecundity and fertility observations.« less

The "soluble" adenylyl cyclase in sperm mediates multiple signaling events required for fertilization.

PubMed

Hess, Kenneth C; Jones, Brian H; Marquez, Becky; Chen, Yanqiu; Ord, Teri S; Kamenetsky, Margarita; Miyamoto, Catarina; Zippin, Jonathan H; Kopf, Gregory S; Suarez, Susan S; Levin, Lonny R; Williams, Carmen J; Buck, Jochen; Moss, Stuart B

2005-08-01

Mammalian fertilization is dependent upon a series of bicarbonate-induced, cAMP-dependent processes sperm undergo as they "capacitate," i.e., acquire the ability to fertilize eggs. Male mice lacking the bicarbonate- and calcium-responsive soluble adenylyl cyclase (sAC), the predominant source of cAMP in male germ cells, are infertile, as the sperm are immotile. Membrane-permeable cAMP analogs are reported to rescue the motility defect, but we now show that these "rescued" null sperm were not hyperactive, displayed flagellar angulation, and remained unable to fertilize eggs in vitro. These deficits uncover a requirement for sAC during spermatogenesis and/or epididymal maturation and reveal limitations inherent in studying sAC function using knockout mice. To circumvent this restriction, we identified a specific sAC inhibitor that allowed temporal control over sAC activity. This inhibitor revealed that capacitation is defined by separable events: induction of protein tyrosine phosphorylation and motility are sAC dependent while acrosomal exocytosis is not dependent on sAC.

Eggs, ethics and exploitation? Investigating women's experiences of an egg sharing scheme

PubMed Central

Haimes, Erica; Taylor, Ken; Turkmendag, Ilke

2012-01-01

Abstract There is a growing global demand for human eggs for the treatment of sub-fertile women and for stem cell-related research. This demand provokes concerns for the women providing the eggs, including their possible exploitation, whether they should be paid, whether they can give properly informed consent and whether their eggs and bodies are becoming commodified. However, few of the debates have benefitted from insights from the women themselves. We address this gap in knowledge by reporting on a study investigating women’s views and experiences of a scheme in which they can volunteer, in their capacity as fertility patients, to ‘share’ their eggs with researchers and receive a reduction in in vitro fertilisation fees. We focus our discussion on the question of exploitation, a concept central to many sociological and ethical interests. In brief, our analysis suggests that while interviewees acknowledge the potential of this scheme to be exploitative, they argue that this is not the case, emphasising their ability to act autonomously in deciding to volunteer. Nonetheless, these freely made decisions do not necessarily take place under circumstances of their choosing. We discuss the implications of this for egg provision in general and for understandings of exploitation. PMID:22443419

Effects of pre-incubation of eggs in fresh water and varying sperm concentration on fertilization rate in sterlet sturgeon, Acipenser ruthenus.

PubMed

Siddique, Mohammad Abdul Momin; Butts, Ian Anthony Ernest; Psenicka, Martin; Linhart, Otomar

2015-08-01

Standardization of fertilization protocols for sterlet Acipenser ruthenus is crucial for improving reproductive techniques and for conservation purposes. Our objectives were to determine the number of sperm (tested 430,000:1, 43,000:1, 4300:1, 430:1 sperm to egg) required to fertilize eggs and explore how pre-incubation of eggs in freshwater for 0min, 0.5min, 1min, and 10min interacts with different sperm ratios. Fertilization success ranged from 29.7% at 430:1 to 84.2% at 430,000:1. Pre-incubation time had no effect on fertilization success at 430,000:1 and 43,000:1 sperm to egg ratios, while it was significant at the 4300:1 and 430:1 ratios. The use of adequate experimental suboptimal sperm to egg ratio revealed a positive effect of pre-incubation time, such that at the 430:1 ratio, 0.5min pre-incubation increased the fertilization rate than 10min. At 0min pre-incubation the proportion of fertilized eggs increased at the 430,000:1 ratio, while at 1min fertilization increased at the 4300:1 ratio. At the 10min pre-incubation time, fertilization increased at the 43,000:1 ratio. Moreover, at the 0.5min pre-incubation time, the 43,000:1 ratio increased the fertilization rate than the 430:1 ratio. Generally, for 430:1 ratio, the fertilization rate is lower than in control. Transmission electron microscopy showed that pre-incubation of eggs in water for <10min does not trigger a cortical reaction or the formation of a perivitelline space. Results suggest that with a low sperm to egg ratio 0.5 to 1min pre-incubation of eggs in freshwater prior to fertilization can enhance fertilization rate of sterlet. Copyright © 2015 Elsevier B.V. All rights reserved.

Cortical mechanics and myosin-II abnormalities associated with post-ovulatory aging: implications for functional defects in aged eggs

PubMed Central

Mackenzie, Amelia C.L.; Kyle, Diane D.; McGinnis, Lauren A.; Lee, Hyo J.; Aldana, Nathalia; Robinson, Douglas N.; Evans, Janice P.

2016-01-01

STUDY HYPOTHESIS Cellular aging of the egg following ovulation, also known as post-ovulatory aging, is associated with aberrant cortical mechanics and actomyosin cytoskeleton functions. STUDY FINDING Post-ovulatory aging is associated with dysfunction of non-muscle myosin-II, and pharmacologically induced myosin-II dysfunction produces some of the same deficiencies observed in aged eggs. WHAT IS KNOWN ALREADY Reproductive success is reduced with delayed fertilization and when copulation or insemination occurs at increased times after ovulation. Post-ovulatory aged eggs have several abnormalities in the plasma membrane and cortex, including reduced egg membrane receptivity to sperm, aberrant sperm-induced cortical remodeling and formation of fertilization cones at the site of sperm entry, and reduced ability to establish a membrane block to prevent polyspermic fertilization. STUDY DESIGN, SAMPLES/MATERIALS, METHODS Ovulated mouse eggs were collected at 21–22 h post-human chorionic gonadotrophin (hCG) (aged eggs) or at 13–14 h post-hCG (young eggs), or young eggs were treated with the myosin light chain kinase (MLCK) inhibitor ML-7, to test the hypothesis that disruption of myosin-II function could mimic some of the effects of post-ovulatory aging. Eggs were subjected to various analyses. Cytoskeletal proteins in eggs and parthenogenesis were assessed using fluorescence microscopy, with further analysis of cytoskeletal proteins in immunoblotting experiments. Cortical tension was measured through micropipette aspiration assays. Egg membrane receptivity to sperm was assessed in in vitro fertilization (IVF) assays. Membrane topography was examined by low-vacuum scanning electron microscopy (SEM). MAIN RESULTS AND THE ROLE OF CHANCE Aged eggs have decreased levels and abnormal localizations of phosphorylated myosin-II regulatory light chain (pMRLC; P = 0.0062). Cortical tension, which is mediated in part by myosin-II, is reduced in aged mouse eggs when compared with young eggs, by ∼40% in the cortical region where the metaphase II spindle is sequestered and by ∼50% in the domain to which sperm bind and fuse (P < 0.0001). Aging-associated parthenogenesis is partly rescued by treating eggs with a zinc ionophore (P = 0.003), as is parthenogenesis induced by inhibition of mitogen-activated kinase (MAPK) 3/1 [also known as extracellular signal-regulated kinase (ERK)1/2] or MLCK. Inhibition of MLCK with ML-7 also results in effects that mimic those of post-ovulatory aging: fertilized ML-7-treated eggs show both impaired fertilization and increased extents of polyspermy, and ML-7-treated young eggs have several membrane abnormalities that are shared by post-ovulatory aged eggs. LIMITATIONS, REASONS FOR CAUTION These studies were done with mouse oocytes, and it remains to be fully determined how these findings from mouse oocytes would compare with other species. For studies using methods not amenable to analysis of large sample sizes and data are limited to what images one can capture (e.g. SEM), data should be interpreted conservatively. WIDER IMPLICATIONS OF THE FINDINGS These data provide insights into causes of reproductive failures at later post-copulatory times. LARGE SCALE DATA Not applicable. STUDY FUNDING AND COMPETING INTEREST(S) This project was supported by R01 HD037696 and R01 HD045671 from the NIH to J.P.E. Cortical tension studies were supported by R01 GM66817 to D.N.R. The authors declare there are no financial conflicts of interest. PMID:26921397

Does egg competition occur in marine broadcast-spawners?

PubMed

Marshall, D J; Evans, J P

2005-09-01

When the availability of sperm limits female reproductive success, competition for sperm, may be an important broker of sexual selection. This is because sperm limitation can increase the variance in female reproductive success, resulting in strong selection on females to compete for limited fertilization opportunities. Sperm limitation is probably common in broadcast-spawning marine invertebrates, making these excellent candidates for investigating scramble competition between broods of eggs and its consequences for female reproductive success. Here, we report our findings from a series of experiments that investigate egg competition in the sessile, broadcast-spawning polychaete Galeolaria caespitosa. We initially tested whether the order in which eggs encounter sperm affects their fertilization success at two ecologically relevant current regimes. We used a split-clutch-split--ejaculate technique to compare the fertilization success of eggs from individual females that had either first access (competition-free treatment) or second access (egg competition treatment) to a batch of sperm. We found that fertilization success depended on the order in which eggs accessed sperm; eggs that were assigned to the competition-free treatment exhibited significantly higher fertilization rates than those assigned to the egg competition treatment at both current speeds. In subsequent experiments we found that prior exposure of sperm to eggs significantly reduced both the quantity and quality of sperm available to fertilize a second clutch of eggs, resulting in reductions in fertilization success at high and low sperm concentrations. These findings suggest that female traits that increase the likelihood of sperm-egg interactions (e.g. egg size) will respond to selection imposed by egg competition.

Hit or Miss: Fertilization Outcomes of Natural Inseminations by Japanese Quail

PubMed Central

Adkins-Regan, Elizabeth

2015-01-01

Variation in fertilization success underlies sexual selection, yet mating does not guarantee fertilization. The relationship between natural inseminations and fertilization success is essential for understanding sexual selection, yet that relationship and its underlying mechanisms are poorly understood in sperm-storing vertebrates such as birds. Here the relationship is analyzed in mating trials using Japanese quail (Coturnix japonica), which show striking variation in the fertilizing success of inseminations. Failures of males’ inseminations to fertilize eggs were mainly due to failures prior to sperm-egg contact. Fertilization probabilities on any given day were unrelated to whether the female had laid an egg the previous day, arguing against stimulation of sperm release from sperm storage tubules by the events of the daily egg-laying cycle. Instead, an unfertilized egg laid between two fertilized eggs predicted a longer sperm storage interval. Both sexes gained similar numbers of fertilized eggs by mating with a second partner the next day, but males, unlike females in a previous study, did not gain by having two females to mate with at the same time. Instead, they were both behaviorally and sperm limited, whereas females gain by mating twice in quick succession. Even double inseminations often failed to fertilize any eggs, and multiple matings would be needed for an entire clutch to be fertilized with high certainty. Paradoxically, this low and probabilistic fertilization success co-occurs with other notable characteristics of male quail suggestive of past sexual selection for increased success, including vigorous copulatory behavior, forced copulations, foamy secretion aiding in sperm competition, large testes and unusual sperm morphology. PMID:26222780

Effects of calcium and magnesium hardness on the fertilization and hatching success of hybrid catfish eggs

USDA-ARS?s Scientific Manuscript database

Hybrid catfish are exclusively produced by strip spawning of channel catfish females, fertilizing stripped eggs with blue catfish sperm, and hatching the fertilized eggs. As egg development takes outside the fish’s body, water hardness is one abioitic parameter, suggested to have a major effect on ...

Calcium and actin in the saga of awakening oocytes.

PubMed

Santella, Luigia; Limatola, Nunzia; Chun, Jong T

2015-04-24

The interaction of the spermatozoon with the egg at fertilization remains one of the most fascinating mysteries of life. Much of our scientific knowledge on fertilization comes from studies on sea urchin and starfish, which provide plenty of gametes. Large and transparent, these eggs have served as excellent model systems for studying egg activation and embryo development in seawater, a plain natural medium. Starfish oocytes allow the study of the cortical, cytoplasmic and nuclear changes during the meiotic maturation process, which can also be triggered in vitro by hormonal stimulation. These morphological and biochemical changes ensure successful fertilization of the eggs at the first metaphase. On the other hand, sea urchin eggs are fertilized after the completion of meiosis, and are particularly suitable for the study of sperm-egg interaction, early events of egg activation, and embryonic development, as a large number of mature eggs can be fertilized synchronously. Starfish and sea urchin eggs undergo abrupt changes in the cytoskeleton and ion fluxes in response to the fertilizing spermatozoon. The plasma membrane and cortex of an egg thus represent "excitable media" that quickly respond to the stimulus with the Ca(2+) swings and structural changes. In this article, we review some of the key findings on the rapid dynamic rearrangements of the actin cytoskeleton in the oocyte/egg cortex upon hormonal or sperm stimulation and their roles in the modulation of the Ca(2+) signals and in the control of monospermic fertilization. Copyright © 2015 Elsevier Inc. All rights reserved.

Egg Cannibalism and its Life History Consequences Vary with Life Stage, Sex, and Reproductive Status in Hippodamia convergens (Coleoptera: Coccinellidae).

PubMed

Bayoumy, Mohamed H; Michaud, J P

2015-08-01

Egg cannibalism is common in Coccinellidae, but its biological consequences have not been fully explored. We examined egg cannibalism by neonates, fourth instars, and adults of Hippodamia convergens Guerin-Meneville for effects on development, reproduction, and progeny fitness. We also tested female adults for ability to avoid cannibalizing their own eggs and first-instar larvae, and both sexes for changes in cannibalism propensity following mating, all in the presence of ad libitum food [larvae: eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), adults: Schizaphis graminum (Rondani)]. Cannibalism by neonates reduced developmental time and increased male body size. Cannibalism in the fourth instar accelerated pupation and led to the production of eggs that hatched faster, regardless of which parent cannibalized. However, egg fertility was improved only by maternal cannibalism in the fourth instar. Females recognized their own egg clusters, sometimes added eggs to them, and preferentially cannibalized nonfilial clusters. Most gravid females cannibalized a first-instar larva within 30 min, whether filial or not. Adult egg cannibalism was similar for virgin males and females, but declined after mating in males, and increased in females, although it had no effect on fecundity or fertility. Daughters of cannibal pairs were heavier than those of other mating combinations, but offspring of noncannibal parents had the fastest development. Reproductive females appeared to use egg cannibalism to reduce risk for their own eggs, increasing the number cannibalized with the number laid. Thus, egg cannibalism in coccinellids varies with life stage, sex, and reproductive condition, independent of food availability, and benefits are life stage specific. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Santella, Luigia, E-mail: santella@szn.it; Limatola, Nunzia; Chun, Jong T.

The interaction of the spermatozoon with the egg at fertilization remains one of the most fascinating mysteries of life. Much of our scientific knowledge on fertilization comes from studies on sea urchin and starfish, which provide plenty of gametes. Large and transparent, these eggs have served as excellent model systems for studying egg activation and embryo development in seawater, a plain natural medium. Starfish oocytes allow the study of the cortical, cytoplasmic and nuclear changes during the meiotic maturation process, which can also be triggered in vitro by hormonal stimulation. These morphological and biochemical changes ensure successful fertilization of the eggsmore » at the first metaphase. On the other hand, sea urchin eggs are fertilized after the completion of meiosis, and are particularly suitable for the study of sperm–egg interaction, early events of egg activation, and embryonic development, as a large number of mature eggs can be fertilized synchronously. Starfish and sea urchin eggs undergo abrupt changes in the cytoskeleton and ion fluxes in response to the fertilizing spermatozoon. The plasma membrane and cortex of an egg thus represent “excitable media” that quickly respond to the stimulus with the Ca{sup 2+} swings and structural changes. In this article, we review some of the key findings on the rapid dynamic rearrangements of the actin cytoskeleton in the oocyte/egg cortex upon hormonal or sperm stimulation and their roles in the modulation of the Ca{sup 2+} signals and in the control of monospermic fertilization. - Highlights: • Besides microtubules, microfilaments may anchor the nucleus to oocyte surface. • The cortical Ca{sup 2+} flash and wave at fertilization mirror electrical membrane change. • Artificial egg activation lacks microvilli extension in the perivitelline space. • Calcium is necessary but not sufficient for cortical granules exocytosis. • Actin cytoskeleton modulates Ca{sup 2+} release at oocyte maturation and fertilization.« less

Effects of triploidy induction on antioxidant defense status in rainbow trout (Oncorhynchus mykiss) during early development.

PubMed

Taghipoor, Kaveh; Keyvanshokooh, Saeed; Salati, Amir Parviz; Pasha-Zanoosi, Hossein; Babaheydari, Samad Bahrami

2016-08-01

The objective of the present study was to examine the antioxidant status of rainbow trout (Oncorhynchus mykiss) during the early stages of development (fertilized egg, eyed egg, alevin and fry) as an effect of triploidy induction. Eggs and milt were taken from eight females and six males. After insemination, the eggs were incubated at 10°C for 10min. Half of the fertilized eggs were then subjected to heat-shock for 10min submerged in a 28°C water bath to induce triploidy. The remainder were incubated normally and used as diploid controls. Three batches of eggs were randomly selected from each group (control and heat-shocked) and were incubated at 10-11°C under the same environmental conditions in hatchery troughs until the fry stage. Triplicate samples of fertilized eggs from each experimental group were randomly selected 1.5h post-fertilization and at the eyed egg stage of development (18 days post-fertilization, dpf). At 27 dpf, triplicate samples of alevins were chosen from each group. Based on ploidy determination experiment performed on both groups, nine diploid and nine triploid fry (76 dpf) were also selected. The triploidy induction success rate was 87.1%. Vitamin C was in lesser concentrations in fertilized eggs and eyed eggs of the heat-shock treatment group as compared with eggs of the diploid group. Alevins of the heat-shock treatment group had a lower superoxide dismutase (SOD) activity than alevins of the diploid group. Glutathione peroxidase (GPx) level was greater in fertilized eggs and alevins of the heat-shock treatment group as compared to diploids. Catalse (CAT) activity was greater in fertilized eggs, alevins and fry of the heat-shock treatment group than those of the diploid group. Malondialdehyde (MDA), as an index of lipid peroxidation, was in greater concentration in fertilized eggs of the group that was heat-shocked, but it was lesser in alevins and fry of the group in which the eggs were heat-shocked as compared to diploid counterparts. The results demonstrate that heat-shock treatment leads to changes in the values of antioxidant enzymes such as SOD, CAT and GPx, and low molecular weight free-radical scavengers such as vitamin C, as well as level of lipid peroxidation. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantification of egg proteome changes during fertilization in sterlet Acipenser ruthenus.

PubMed

Niksirat, Hamid; Andersson, Liselotte; Golpour, Amin; Chupani, Latifeh; James, Peter

2017-08-19

Eggs of sterlet are discharged outside into ambient aquatic environment where egg activation and fertilization occur. Effects of different activation media including freshwater and clay suspension on protein abundances of egg were quantified in sterlet Acipenser ruthenus. In-gel digestion and high resolution mass spectrometry were used for label-free protein quantification in the eggs of five females. No significant (p > 0.05) difference was found between protein abundances in eggs activated with different media. However, results showed significant (p < 0.05, fold change ≥2) reduction in the abundances of nine proteins including six glycoproteins, enolase and heat shock protein in activated groups compared to freshly ovulated eggs as control. The fact that abundance of proteasome subunit alpha significantly reduced only in eggs which were activated by clay suspension suggests that activation medium can somehow intervene with protein regulation during fertilization. In conclusion, external fertilization in sturgeon egg is accompanied by huge release of proteins into the external environment that may participate in the construction of a transient microenvironment around egg for attraction and protection of spermatozoa to ensure ensuing fertilization. Data are available via ProteomeXchange with identifier PXD006232. Copyright © 2017 Elsevier Inc. All rights reserved.

New technique for fertilizing eggs of burbot, asp and ide under hatchery conditions.

PubMed

Kucharczyk, Dariusz; Nowosad, Joanna; Łuczyński, Marek J; Targońska, Katarzyna

2016-09-01

The development of a new protocol for egg fertilization may increase embryo survival and benefit the aquaculture process. In the present study, a new technique of partially adding sperm to activated eggs in the artificial fertilization of burbot (Lota lota), ide (Leuciscus idus) and asp (Aspius aspius) eggs was evaluated. If the same volume of sperm was divided into two or three parts and added to eggs in 30-60s intervals, it significantly improved embryo survival at the eyed-egg-stage of development. In the present study, the periodic addition of spermatozoa to eggs affected fertilization (ide and asp) and embryo survival rates (ide, asp and burbot) and might be successfully applied under hatchery conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Handling of boar spermatozoa during and after flow cytometric sex-sorting process to improve their in vitro fertilizing ability.

PubMed

del Olmo, D; Parrilla, I; Gil, M A; Maside, C; Tarantini, T; Angel, M A; Roca, J; Martinez, E A; Vazquez, J M

2013-09-01

The objective of this study was to develop an adequate sperm handling protocol in order to obtain a sex-sorted sperm population with an optimal fertilizing ability. For this purpose, different aspects of the sorting procedure were examined. The effects of the high dilution rates (experiment 1), type of collection medium used (experiment 2), and sheath fluid composition (experiment 3) on sorted boar sperm quality and function were evaluated. Sperm quality was assessed by motility and viability tests, whereas sperm function was evaluated by an in vitro fertilization assay which determined the penetration and polyspermy rates as well as the mean number of sperm penetrating each oocyte. In experiment 1, the results obtained indicated that the high dilution rates did not cause a decrease either in the sperm quality parameters evaluated or the in vitro fertilization ability of spermatozoa. In experiment 2, although sperm quality was not affected, fertilizing ability was compromised after sorting, regardless of the collection medium that was used. In the experiment 3, all groups displayed adequate sperm quality values, but higher in vitro fertility parameters were obtained for spermatozoa sorted in presence of EDTA in the sheath fluid and egg yolk (EY) in the collection media when compared with those sorted in absence of these protective agents. No differences in penetration rates between unsorted highly diluted (control) and sorted sperm in the presence of EDTA and EY were observed. In conclusion, fertilizing ability was compromised in sex-sorted sperm. The addition of EDTA to sheath fluid and EY to collection medium improved boar sperm fertilizing ability, and both agents should be included as essential media components in future studies. Copyright © 2013 Elsevier Inc. All rights reserved.

Calcium-responsive contractility during fertilization in sea urchin eggs.

PubMed

Stack, Christianna; Lucero, Amy J; Shuster, Charles B

2006-04-01

Fertilization triggers a reorganization of oocyte cytoskeleton, and in sea urchins, there is a dramatic increase in cortical F-actin. However, the role that myosin II plays during fertilization remains largely unexplored. Myosin II is localized to the cortical cytoskeleton both before and after fertilization and to examine myosin II contractility in living cells, Lytechinus pictus eggs were observed by time-lapse microscopy. Upon sperm binding, a cell surface deflection traversed the egg that was followed by and dependent on the calcium wave. The calcium-dependence of surface contractility could be reproduced in unfertilized eggs, where mobilization of intracellular calcium in unfertilized eggs under compression resulted in a marked contractile response. Lastly, inhibition of myosin II delayed absorption of the fertilization cone, suggesting that myosin II not only responds to the same signals that activate eggs but also participates in the remodeling of the cortical actomyosin cytoskeleton during the first zygotic cell cycle. (c) 2006 Wiley-Liss, Inc.

Calcium-Responsive Contractility During Fertilization in Sea Urchin Eggs

PubMed Central

Stack, Christianna; Lucero, Amy J.; Shuster, Charles B.

2008-01-01

Fertilization triggers a reorganization of oocyte cytoskeleton, and in sea urchins there is a dramatic increase in cortical F-actin. However, the role that myosin II plays during fertilization remains largely unexplored. Myosin II is localized to the cortical cytoskeleton both prior to- and following fertilization, and to examine myosin II contractility in living cells, Lytechinus pictus eggs were observed by time-lapse microscopy. Upon sperm binding, a cell surface deflection traversed the egg that was followed- and dependent on the calcium wave. The calcium-dependence of surface contractility could be reproduced in unfertilized eggs, where mobilization of intracellular calcium in unfertilized eggs under compression resulted in a marked contractile response. Lastly, inhibition of myosin II delayed absorption of the fertilization cone, suggesting that myosin II not only responds to the same signals that activate eggs, but also participates in the remodeling of the cortical actomyosin cytoskeleton during the first zygotic cell cycle. PMID:16470603

Effects of Cancer Treatment on Fertility (For Parents)

MedlinePlus

... reproductive organs to remove the cancer. Sperm and Egg Preservation Options If your child's treatment carries a ... vitro fertilization (sperm are used to fertilize an egg outside of the uterus, then the fertilized embryo ...

Scanning electron microscope studies of sea urchin fertilization. I. Eggs with vitelline layers.

PubMed

Tegner, M J; Epel, D

1976-07-01

The surface coats of sea urchin eggs and the events of fertilization which take place on these surfaces were examined with the scanning electron microscope (SEM). Gametes of Stronglyocentrotus purpuratus and Lytechinus pictus were considered in detail; eggs of seven other echinoids were examined for comparative purposes. Jelly coats, preserved by varying the pH of fixation, were found to vary in morphology and solubility properties between species. The vitelline layers of the nine echinoids are characterized by arrays of projections which are impressions of cytoplasmic microvilli in the vitelline layer. After sperm bind to the egg surface via the acrosomal process, fine filaments, apparently an egg response to insemination, further connect some sperm heads and tails to the egg. The cortical reactions spread out as a wave from where the fertilizing sperm fused with the egg; separation of the vitelline layer proceeds as a smooth wave from S. purpuratus eggs and as a series of localized separations in L. pictus eggs. The fertilization membranes of S. purpuratus and Allocentrotus fragilis zygotes are expanded replicas of their respective vitelline layers, suggesting that fertilization membranes are formed by an unfolding of the vitelline layer.

Artificial activation of mature unfertilized eggs in the malaria vector mosquito, Anopheles stephensi (Diptera, Culicidae).

PubMed

Yamamoto, Daisuke S; Hatakeyama, Masatsugu; Matsuoka, Hiroyuki

2013-08-01

In the past decade, many transgenic lines of mosquitoes have been generated and analyzed, whereas the maintenance of a large number of transgenic lines requires a great deal of effort and cost. In vitro fertilization by an injection of cryopreserved sperm into eggs has been proven to be effective for the maintenance of strains in mammals. The technique of artificial egg activation is a prerequisite for the establishment of in vitro fertilization by sperm injection. We demonstrated that artificial egg activation is feasible in the malaria vector mosquito, Anopheles stephensi (Diptera, Culicidae). Nearly 100% of eggs dissected from virgin females immersed in distilled water darkened, similar to normally oviposited fertilized eggs. It was revealed by the cytological examination of chromosomes that meiotic arrest was relieved in these eggs approximately 20 min after incubation in water. Biochemical examinations revealed that MAPK (mitogen-activated protein kinase)/ERK (extracellular signal-regulated protein kinase) and MEK (MAPK/ERK kinase) were dephosphorylated similar to that in fertilized eggs. These results indicate that dissected unfertilized eggs were activated in distilled water and started development. Injection of distilled water into body cavity of the virgin blood-fed females also induced activation of a portion of eggs in the ovaries. The technique of artificial egg activation is expected to contribute to the success of in vitro fertilization in A. stephensi.

Effects of phalloidin microinjection and localization of fluorescein-labeled phalloidin in living sand dollar eggs.

PubMed

Hamaguchi, Y; Mabuchi, I

1982-01-01

Effects of microinjection of phalloidin on fertilization and cleavage of sand dollar (Clypeaster japonicus and Scaphechinus mirabilis) eggs were studied. The drug, previously injected into unfertilized eggs, showed no effect on the elevation of the fertilization membrane upon insemination up to an intracellular concentration of 50 microM. However, the movement of the egg pronucleus to the sperm pronucleus was inhibited and the fusion of pronuclei did not occur. The subsequent development no longer took place. When phalloidin was injected into fertilized eggs, the thickness of the cortical layer increased and the microvilli became conspicuous. Both nuclear division and cleavage were inhibited at the intracellular concentration of more than 20 microM, though the latter seemed to be more sensitive to phalloidin than the former. Fluorescein-labeled phalloidin (FL-phalloidin) was injected into eggs in order to investigate F-actin localization by fluorescence microscopy. In both unfertilized and fertilized eggs, FL-phalloidin was localized in the cortical layer within 1 min after injection. It was also localized in the cortical layer as radially oriented rod-like structures when injected into fertilized eggs before the disappearance of the nuclear membrane. No distinct fluorescence was detected in the mitotic apparatus or in the cleavage furrow. FL-phalloidin redistributed gradually into egg cytoplasm. In unfertilized eggs, fluorescent rods were found especially in the egg pronucleus 30 min after injection.

Understanding the effects of low salinity on fertilization success and early development in the sand dollar Echinarachnius parma.

PubMed

Allen, Jonathan D; Pechenik, Jan A

2010-04-01

Free-spawning marine invertebrates that live near shore or in estuaries may experience reduced fertilization success during low-salinity events. Although several studies have documented reproductive failure at reduced salinity in estuarine animals, few have looked at whether developmental failure is due to a failure of fertilization or to a failure of fertilized eggs to cleave. In this study, we examined the effects of salinities ranging from 18 to 32 psu on fertilization success and early development in the sand dollar Echinarachnius parma. In addition to decoupling the effects of low salinity on fertilization from its effects on early cleavage, we also assessed whether eggs or sperm were the weak link in accounting for reproductive failure. We found that both fertilization and cleavage failed at salinities below about 22 psu but that development could be partially rescued by returning zygotes to full-strength seawater. We also found that sperm remained active and capable of fertilizing eggs even after being exposed to low salinities for 30 min.. Taken together, these results suggest that reproductive failure at low salinities in E. parma is due more to an inability of the fertilized eggs to cleave than to an inability of sperm to fertilize eggs.

β1 Integrin is an Adhesion Protein for Sperm Binding to Eggs

PubMed Central

Baessler, Keith A.; Lee, Younjoo; Sampson, Nicole S.

2009-01-01

We investigated the role of β1 integrin in mammalian fertilization and the mode of inhibition of fertilinβ-derived polymers. We determined that polymers displaying the Glu-Cys-Asp peptide from the fertilinβ disintegrin domain mediate inhibition of mammalian fertilization through a β1 integrin receptor on the egg surface. Inhibition of fertilization is a consequence of competition with sperm binding to the cell surface, not activation of an egg-signaling pathway. The presence of the β1 integrin on the egg surface increases the rate of sperm attachment, but does not alter the total number of sperm that can attach or fuse to the egg. We conclude that the presence of β1 integrin enhances the initial adhesion of sperm to the egg plasma membrane and that subsequent attachment and fusion are mediated by additional egg and sperm proteins present in the β1 integrin complex. Therefore, the mechanisms by which sperm fertilize wild-type and β1 knockout eggs are different. PMID:19338281

78 FR 13301 - Notice of Request for Extension of Approval of an Information Collection; Spring Viremia of Carp...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-27

... Restrictions on Certain Live Fish, Fertilized Eggs, and Gametes AGENCY: Animal and Plant Health Inspection... with the regulations for the importation of live fish, fertilized eggs, and gametes to prevent the... for the importation of live fish, fertilized eggs, and gametes, contact Dr. Christa Speekmann, Import...

[Fish ovarian fluid contains protease inhibitors].

PubMed

Minin, A A; Ozerova, S G

2015-01-01

Studies of the conditions under which fish egg is activated spontaneously without the sperm showed that the egg retains the ability for fertilization in the ovarian (coelomic) fluid, which surrounds it in the gonad cavity after ovulation. Earlier, we showed that, in artificial media, the spontaneous activation is suppressed by protease inhibitors. In this study, we investigated the presence of natural protease inhibitors in the ovarian fluid and showed that the ovarian fluid of zebrafish and loach contains protease inhibitors, in particular, type I serpin a, a protein inhibitor of trypsin proteases.

The cooling time of fertile chicken eggs at different stages of incubation.

PubMed

Mortola, Jacopo P; Gaonac'h-Lovejoy, Vanda

2016-01-01

We asked whether or not the thermal characteristics of fertile avian eggs changed throughout incubation. The cooling and warming times, expressed by the time constant τ of the egg temperature response to a rapid change in ambient temperature, were measured in fertile chicken eggs at early (E7), intermediate (E11) and late (E20) stages of embryonic development. Same measurements were conducted on eggs emptied of their content and refilled with water by various amounts. The results indicated that (1) the τ of a freshly laid egg was ~50 min; (2) τ decreased linearly with the drop in egg water volume; (3) the dry eggshell had almost no thermal resistance but its wet inner membrane contributed about one-third to the stability of egg temperature; (4) the egg constituents (yolk, albumen and embryonic tissues) and the chorioallantoic circulation had no measurable effect on τ; (5) the presence of an air pocket equivalent in volume to the air cell of fertile eggs reduced τ by about 3 min (E7), 5 min (E11) and 11 min (E20). Hence, in response to warming the egg τ at E20 was slightly shorter than at E7. In response to cooling, the egg τ at E20 was similar to, or longer than, E7 because embryonic thermogenesis (evaluated by measurements of oxygen consumption during cold) offset the reduction in τ introduced by the air cell. In conclusion, until the onset of thermogenesis the thermal behavior of a fertile egg is closely approximated by that of a water-filled egg with an air volume equivalent to the air cell. It is possible to estimate the cooling τ of avian eggs of different species from their weight and incubation time. Copyright © 2015 Elsevier Ltd. All rights reserved.

Semen collection and fertility in naturally fertile sandhill cranes

USGS Publications Warehouse

Chen, G.; Gee, G.F.; Nicolich, Jane M.; Taylor, J.A.; Urbanek, R.P.; Stahlecker, D.W.

1997-01-01

Aviculturists often ask if semen collection will interfere with fertility in naturally fertile pairs of cranes. We used 12 naturally fertile Florida sandhill crane (Grus canadensis pratensis) pairs for this study, 6 control and 6 experimental. All pairs had produced fertile eggs in previous years and were in out-of-doors pens scattered throughout different pen complexes, within auditory range but physically isolated. Semen was collected on Tuesday mornings and Friday afternoons from 26 February 1993 to 4 June 1993. We used standard artificial insemination methods to collect and to evaluate the semen and spermatozoa. Semen collection did not affect semen quality or quantity. Semen volume, sperm density, sperm motility, sperm morphology, sperm live, sperm number per collection, and male response to semen collection exhibited significant daily variation (P < 0.05). Although semen collection began 13 days before the first egg in the experimental group, we observed no differences in the date of first egg laid or in fertility between experimental and control groups. Also, we observed no differences in the interval between clutches or in the percentage of broken eggs between experimental and control groups. Sires consistently producing better semen samples produced fewer fertile eggs than sires producing poorer semen samples (r = 0.60).

Effects of salinity and sea salt type on egg activation, fertilization, buoyancy and early embryology of European eel, Anguilla anguilla.

PubMed

Sørensen, Sune Riis; Butts, Ian Anthony Ernest; Munk, Peter; Tomkiewicz, Jonna

2016-02-01

Improper activation and swelling of in vitro produced eggs of European eel, Anguilla anguilla, has been shown to negatively affect embryonic development and hatching. We investigated this phenomenon by examining the effects of salinity and sea salt type on egg dimensions, cell cleavage patterns and egg buoyancy. Egg diameter after activation, using natural seawater adjusted to different salinities, varied among female eels, but no consistent pattern emerged. Activation salinities between 30-40 practical salinity unit (psu) produced higher quality eggs and generally larger egg diameters. Chorion diameters reached maximal values of 1642 ± 8 μm at 35 psu. A positive relationship was found between egg neutral buoyancy and activation salinity. Nine salt types were investigated as activation and incubation media. Five of these types induced a substantial perivitelline space (PVS), leading to large egg sizes, while the remaining four salt types resulted in smaller eggs. All salt types except NaCl treatments led to high fertilization rates and had no effect on fertilization success as well as egg neutral buoyancies at 7 h post-fertilization. The study points to the importance of considering ionic composition of the media when rearing fish eggs and further studies are encouraged.

Analysis of signal transduction in cell-free extracts and rafts of Xenopus eggs.

PubMed

Tokmakov, Alexander A; Iwasaki, Tetsushi; Sato, Ken-Ichi; Fukami, Yasuo

2010-05-01

Intracellular signaling during egg activation/fertilization has been extensively studied using intact eggs, which can be manipulated by microinjection of different mRNAs, proteins, or chemical drugs. Furthermore, egg extracts, which retain high CSF activity (CSF-arrested extracts), were developed for studying fertilization/activation signal transduction, which have significant advantages as a model system. The addition of calcium to CSF-arrested extracts initiates a plethora of signaling events that take place during egg activation. Hence, the signaling downstream of calcium mobilization has been successfully studied in the egg extracts. Moreover, despite disruption of membrane-associated signaling compartments and ordered compartmentalization during extract preparation, CSF-arrested extracts can be successfully used to study early signaling events, which occur upstream of calcium release during egg activation/fertilization. In combination with the CSF-arrested extracts, activated egg rafts can reproduce some events of egg activation, including PLCgamma activation, IP3 production, transient calcium release, MAPK inactivation, and meiotic exit. This becomes possible due to complementation of the sperm-induced egg activation signaling machinery present in the rafts with the components of signal transduction system localized in the extracts. Herein, we describe protocols for studying molecular mechanisms of egg fertilization/activation using cell-free extracts and membrane rafts prepared from metaphase-arrested Xenopus eggs.

Exposure to bisphenol A in young adult mice does not alter ovulation but does alter the fertilization ability of oocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore-Ambriz, Teresita Rocio; Acuña-Hernández, Deyanira Guadalupe; Ramos-Robles, Brenda

Follicle growth culminates in ovulation, which allows for the expulsion of fertilizable oocytes and the formation of corpora lutea. Bisphenol A (BPA) is present in many consumer products, and it has been suggested that BPA impairs ovulation; however, the underlying mechanisms are unknown. Therefore, this study first evaluated whether BPA alters ovulation by affecting folliculogenesis, the number of corpora lutea or eggs shed to the oviduct, ovarian gonadotropin responsiveness, hormone levels, and estrous cyclicity. Because it has been suggested (but not directly confirmed) that BPA exerts toxic effects on the fertilization ability of oocytes, a second aim was to evaluatemore » whether BPA impacts the oocyte fertilization rate using an in vitro fertilization assay and mating. The possible effects on early zygote development were also examined. Young adult female C57BL/6J mice (39 days old) were orally dosed with corn oil (vehicle) or 50 μg/kg bw/day BPA for a period encompassing the first three reproductive cycles (12–15 days). BPA exposure did not alter any parameters related to ovulation. Moreover, BPA exposure reduced the percentage of fertilized oocytes after either in vitro fertilization or mating, but it did not alter the zygotic stages. The data indicate that exposure to the reference dose of BPA does not impact ovulation but that it does influence the oocyte quality in terms of its fertilization ability. - Highlights: • Bisphenol A targets the fertilization ability of oocytes. • Bisphenol A does not alter ovulation. • Young adult females may be susceptible to the effects of bisphenol A on fertilization.« less

Metabolic similarities between fertilization and phagocytosis. Conservation of a peroxidatic mechanism

PubMed Central

1979-01-01

At the time of fertilization, sea urchin eggs release a peroxidase which, together with H2O2 generated by a respiratory burst, is responsible for hardening of the fertilization membrane. We demonstrate here that the ovoperoxidase of unfertilized eggs is located in cortical granules and, after fertilization, is concentrated in the fertilization membrane. Fertilization of sea urchin eggs or their parthenogenetic activation with the ionophor A23187 also results in (a) the conversion of iodide to a trichloroacetic acid-precipitable form (iodination), (b) the deiodination of eggs exogenously labeled with myeloperoxidase and H2O2, (c) the degradation of thyroxine as measured by the recovery of the released radioiodine at the origin and in the inorganic iodide spot on paper chromatography, and (d) the conversion of estradiol to an alcohol-precipitable form (estrogen binding). The iodination reaction and the binding of estradio occurs predominantly in the fertilization membrane where the ovoperoxidase is concentrated. From the estimation of the kinetics of incorporation of iodine, we determine that the peroxidative system is active for 30 min after fertilization, long after hardening of the fertilization membrane is complete. Most of the bound iodine is lost during the hatching process. Iodination of albumin is catalyzed by the material released from the egg during fertilization, when combined with H2O2 and iodide. Iodination, thyroxine degradation, and estradiol binding are inhibited by azide, cyanide, aminotriazole, methimazole, ascorbic acid and ergothioneine, all of which can inhibit peroxidase-catalyzed reactions. These responses of the sea urchin egg to fertilization are strikingly similar to the changes induced in polymorphonuclear leukocytes by phagocytosis and, in both instances, a peroxidative mechanism may be involved. PMID:372484

Distinct roles for multiple Src family kinases at fertilization.

PubMed

O'Neill, Forest J; Gillett, Jessica; Foltz, Kathy R

2004-12-01

Egg activation at fertilization requires the release of Ca2+ from the endoplasmic reticulum of the egg. Recent evidence indicates that Src family kinases (SFKs) function in the signaling pathway that initiates this Ca2+ release in the eggs of many deuterostomes. We have identified three SFKs expressed in starfish (Asterina miniata) eggs, designated AmSFK1, AmSFK2 and AmSFK3. Antibodies made against the unique domains of each AmSFK protein revealed that all three are expressed in eggs and localized primarily to the membrane fraction. Both AmSFK1 and AmSFK3 (but not AmSFK2) are necessary for egg activation, as determined by injection of starfish oocytes with dominant-interfering Src homology 2 (SH2) domains, which specifically delay and reduce the initial release of Ca2+ at fertilization. AmSFK3 exhibits a very rapid and transient kinase activity in response to fertilization, peaking at 30 seconds post sperm addition. AmSFK1 kinase activity also increases transiently at fertilization, but peaks later, at 2 minutes. These results indicate that there are multiple SFKs present in starfish eggs with distinct, perhaps sequential, signaling roles.

Egg embryo development detection with hyperspectral imaging

NASA Astrophysics Data System (ADS)

Lawrence, Kurt C.; Smith, Douglas P.; Windham, William R.; Heitschmidt, Gerald W.; Park, Bosoon

2006-10-01

In the U. S. egg industry, anywhere from 130 million to over one billion infertile eggs are incubated each year. Some of these infertile eggs explode in the hatching cabinet and can potentially spread molds or bacteria to all the eggs in the cabinet. A method to detect the embryo development of incubated eggs was developed. Twelve brown-shell hatching eggs from two replicates (n=24) were incubated and imaged to identify embryo development. A hyperspectral imaging system was used to collect transmission images from 420 to 840 nm of brown-shell eggs positioned with the air cell vertical and normal to the camera lens. Raw transmission images from about 400 to 900 nm were collected for every egg on days 0, 1, 2, and 3 of incubation. A total of 96 images were collected and eggs were broken out on day 6 to determine fertility. After breakout, all eggs were found to be fertile. Therefore, this paper presents results for egg embryo development, not fertility. The original hyperspectral data and spectral means for each egg were both used to create embryo development models. With the hyperspectral data range reduced to about 500 to 700 nm, a minimum noise fraction transformation was used, along with a Mahalanobis Distance classification model, to predict development. Days 2 and 3 were all correctly classified (100%), while day 0 and day 1 were classified at 95.8% and 91.7%, respectively. Alternatively, the mean spectra from each egg were used to develop a partial least squares regression (PLSR) model. First, a PLSR model was developed with all eggs and all days. The data were multiplicative scatter corrected, spectrally smoothed, and the wavelength range was reduced to 539 - 770 nm. With a one-out cross validation, all eggs for all days were correctly classified (100%). Second, a PLSR model was developed with data from day 0 and day 3, and the model was validated with data from day 1 and 2. For day 1, 22 of 24 eggs were correctly classified (91.7%) and for day 2, all eggs were correctly classified (100%). Although the results are based on relatively small sample sizes, they are encouraging. However, larger sample sizes, from multiple flocks, will be needed to fully validate and verify these models. Additionally, future experiments must also include non-fertile eggs so the fertile / non-fertile effect can be determined.

Intracellular pH change does not accompany egg activation in the mouse.

PubMed

Phillips, K P; Baltz, J M

1996-09-01

In the sea urchin, some other marine invertebrates, and the frog, Xenopus, egg activation at fertilization is accompanied by an increase in intracellular pH (pHi). We measured pHi in germinal vesicle (GV)-intact mouse oocytes, ovulated eggs, and in vivo fertilized zygotes using the pH indicator dye, SNARF-1. The mean pH, was 6.96 +/- 0.004 (+/- SEM) in GV-intact oocytes, 7.00 +/- 0.01 in ovulated, unfertilized eggs, and 7.02 +/- 0.01 in fertilized zygotes, indicating no sustained changes in pHi after germinal vesicle breakdown (GVBD) or fertilization. To examine whether transient changes in pHi occur shortly after egg activation, mouse eggs were parthenogenetically activated by 7% ethanol in phosphate buffered saline (PBS); no significant change in pHi followed ethanol activation. Since increased Na+/H+ antiporter activity is responsible for pHi increase in the sea urchin, pHi was measured in the absence of added bicarbonate or CO2 (a condition under which the antiporter would be the only major pHi regulatory mechanism able to operate, since the others were bicarbonate-dependent) in GV-intact oocytes, ovulated eggs, and in vivo fertilized zygotes to determine whether a Na+/H+ antiporter was activated. There was no physiologically significant difference in pHi after GVBD or fertilization, when pHi was measured in bicarbonate-free medium, nor any change upon parthenogenetic activation. Thus, a change in pHi is not a feature of egg activation in the mouse.

Egg Water from the Amphibian Bufo arenarum Modulates the Ability of Homologous Sperm to Undergo the Acrosome Reaction in the Presence of the Vitelline Envelope1

PubMed Central

Krapf, Darío; O'Brien, Emma D.; Cabada, Marcelo O.; Visconti, Pablo E.; Arranz, Silvia E.

2008-01-01

Sperm from the toad Bufo arenarum must penetrate the egg jelly before reaching the vitelline envelope (VE), where the acrosome reaction is triggered. When the jelly coat is removed, sperm still bind to the VE, but acrosomal exocytosis is not promoted. Our previous work demonstrated that diffusible substances of the jelly coat, termed “egg water” (EW), triggered capacitation-like changes in B. arenarum sperm, promoting the acquisition of a transient fertilizing capacity. In the present work, we correlated this fertilizing capacity with the ability of the sperm to undergo the acrosome reaction, further substantiating the role of the jelly coat in fertilization. When sperm were exposed to the VE, only those preincubated in EW for 5 or 8 min underwent an increase in the intracellular Ca2+ concentration ([Ca2+]i), which led to acrosomal exocytosis. Responsiveness to the VE was not acquired on preincubation in EW for 2 or 15 min or in Ringer solution regardless of the preincubation time. In contrast, depletion of intracellular Ca2+ stores (induced by thapsigargin) promoted [Ca2+]i rise and the acrosome reaction even in sperm that were not exposed to EW. Acrosomal exocytosis was blocked by the presence of Ca2+ chelators independent of whether a physiological or pharmacological stimulus was used. However, Ni2+ and mibefradil prevented [Ca2+]i rise and the acrosome reaction of sperm exposed to the VE but not of sperm exposed to thapsigargin. These data suggest that the acrosomal responsiveness of B. arenarum sperm, present during a narrow period, is acquired during EW incubation and involves the modulation of a voltage-dependent Ca2+ channel. PMID:18923159

Egg water from the amphibian Bufo arenarum modulates the ability of homologous sperm to undergo the acrosome reaction in the presence of the vitelline envelope.

PubMed

Krapf, Darío; O'Brien, Emma D; Cabada, Marcelo O; Visconti, Pablo E; Arranz, Silvia E

2009-02-01

Sperm from the toad Bufo arenarum must penetrate the egg jelly before reaching the vitelline envelope (VE), where the acrosome reaction is triggered. When the jelly coat is removed, sperm still bind to the VE, but acrosomal exocytosis is not promoted. Our previous work demonstrated that diffusible substances of the jelly coat, termed "egg water" (EW), triggered capacitation-like changes in B. arenarum sperm, promoting the acquisition of a transient fertilizing capacity. In the present work, we correlated this fertilizing capacity with the ability of the sperm to undergo the acrosome reaction, further substantiating the role of the jelly coat in fertilization. When sperm were exposed to the VE, only those preincubated in EW for 5 or 8 min underwent an increase in the intracellular Ca(2+) concentration ([Ca(2+)](i)), which led to acrosomal exocytosis. Responsiveness to the VE was not acquired on preincubation in EW for 2 or 15 min or in Ringer solution regardless of the preincubation time. In contrast, depletion of intracellular Ca(2+) stores (induced by thapsigargin) promoted [Ca(2+)](i) rise and the acrosome reaction even in sperm that were not exposed to EW. Acrosomal exocytosis was blocked by the presence of Ca(2+) chelators independent of whether a physiological or pharmacological stimulus was used. However, Ni(2+) and mibefradil prevented [Ca(2+)](i) rise and the acrosome reaction of sperm exposed to the VE but not of sperm exposed to thapsigargin. These data suggest that the acrosomal responsiveness of B. arenarum sperm, present during a narrow period, is acquired during EW incubation and involves the modulation of a voltage-dependent Ca(2+) channel.

The effects of semen collection on fertility in captive, naturally fertile, sandhill cranes

USGS Publications Warehouse

Chen, G.; Gee, G.F.; Nicolich, Jane M.; Taylor, J.A.

2001-01-01

We tested to see if semen collection interferes with fertility in naturally fertile pairs of cranes. We used 12 naturally fertile, Florida sandhill crane (Grus canadensis pratensis) pairs for this study, 6 control and 6 experimental. All pairs had previously produced fertile eggs. Semen was collected on Tuesday mornings and Friday afternoons from 26 February 1993 to 4 June 1993. We used standard artificial insemination methods to collect and to evaluate the semen and spermatozoa. Semen collection had minimal effect on semen quality and semen quantity. Semen volume, sperm density, sperm motility, sperm morphology, sperm viability, sperm number per collection, and male response to semen collection exhibited significant daily variation. Although semen collection began 13 days before the first egg in the experimental group, we did not observe differences in the date of first egg laid or in fertility between experimental and control groups. Also, we observed no statistically significant differences in the interval between clutches or in the percentage of broken eggs between experimental and control groups. However, 4 eggs were broken by adults during the disturbance associated with capturing birds for semen collection. We found that females with mates from which we consistently gathered better semen samples produced fewer fertile eggs than females with sires producing poorer semen samples (r = 0.60). We interpret these results to mean that males that were successfully breeding with their mates had little left at the time of our collection.

Calcium Signaling and Meiotic Exit at Fertilization in Xenopus Egg

PubMed Central

Tokmakov, Alexander A.; Stefanov, Vasily E.; Iwasaki, Tetsushi; Sato, Ken-Ichi; Fukami, Yasuo

2014-01-01

Calcium is a universal messenger that mediates egg activation at fertilization in all sexually reproducing species studied. However, signaling pathways leading to calcium generation and the mechanisms of calcium-induced exit from meiotic arrest vary substantially among species. Here, we review the pathways of calcium signaling and the mechanisms of meiotic exit at fertilization in the eggs of the established developmental model, African clawed frog, Xenopus laevis. We also discuss calcium involvement in the early fertilization-induced events in Xenopus egg, such as membrane depolarization, the increase in intracellular pH, cortical granule exocytosis, cortical contraction, contraction wave, cortical rotation, reformation of the nuclear envelope, sperm chromatin decondensation and sister chromatid segregation. PMID:25322156

Voltage-clamp study of the activation currents and fast block to polyspermy in the egg of Xenopus laevis.

PubMed

Glahn, David; Nuccitelli, Richard

2003-04-01

Voltage-clamped mature, jelly-intact Xenopus eggs were used to carefully examine the ionic currents crossing the plasma membrane before, during, and after fertilization. The bulk of the fertilization current was transient, of large amplitude, and reversed at the predicted Cl- reversal potential. However, the large amplitude fertilization current was preceded by a small, step-like increase in holding current. This small increase in holding current is referred to in this paper as Ion to acknowledge its qualitative similarity to the Ion current previously described in the sea urchin. It was observed in both fertilized and artificially activated eggs, and was found to be unaffected by 10 mm tetra-ethyl ammonium (TEA), a concentration found to block K+ currents in Rana pipiens. Current-voltage relationships are presented for the large fertilization potential, and show that the fertilization currents have a marked outward rectification and are voltage sensitive. These properties are in contrast to the total lack of rectification and slight voltage sensitivity seen before or after the fertilization currents. The time required for sperm to fertilize the egg was found to be voltage dependent with a relatively more depolarized voltage requiring a longer time for fertilization to occur. The percentage of eggs blocked with varying potential levels was determined and this information was fitted to a modified Boltzmann equation having a midpoint of -9 mV.

Evaluation of four bed bug traps for surveillances of brown dog ticks (Acari: Ixodidae)

USDA-ARS?s Scientific Manuscript database

The brown dog tick can be a serious residential pest due to its unique ability, among ticks, to complete its lifecycle indoors. A single engorged and fertilized female tick can oviposit around 4,000 eggs, allowing indoor establishment to be rapid and easy to miss in early-stage infestations. Acari...

The Effect of Photobiomodulation on the Sea Urchin Paracentrotus lividus (Echinodermata) Using Higher-Fluence on Fertilization, Embryogenesis, and Larval Development: An In Vitro Study.

PubMed

Amaroli, Andrea; Gambardella, Chiara; Ferrando, Sara; Hanna, Reem; Benedicenti, Alberico; Gallus, Lorenzo; Faimali, Marco; Benedicenti, Stefano

2017-03-01

The aim of this study was to investigate the photobiomodulation (PBM) effect of the 808 nm diode laser irradiation on spermatozoa, eggs, fertilized eggs, embryos, and larvae of Paracentrotus lividus, using two different power settings. Studies have shown the possible use of PBM in artificial insemination. These have shown the potential effect of low-power laser irradiation on spermatozoa, while there are few studies on the effect of laser photonic energy on oocytes and almost no reports on the influence of lasers in embryogenesis. P. lividus gametes, zygotes, embryos, and larvae were irradiated using the 808 nm diode laser (fluence 64 J/cm 2 using 1 W or 192 J/cm 2 with 3 W) with a flat-top hand-piece delivery, compared to a control without laser irradiation (0 J/cm 2 -0 W). The fertilization rate and the early developmental stages were investigated. The fertilization ability was not affected by the sperm/egg irradiation. At the gastrula stage, no significant differences were observed compared with the control samples. In the late pluteus stage, there were no differences in the developmental percentage observed between the control and the treated samples (1 W), with the exception of larvae from gastrulae and larvae, which were irradiated at 3 W. This study has demonstrated that both the 64 J/cm 2 -1 W and the 192 J/cm 2 -3 W do not induce morphological damage on the irradiated P. lividus gametes whose zygotes generate normal embryos and larvae. Our data therefore support the assumption to use higher fluence in preliminary studies on in vitro fertilization.

Revisiting "The fertilization fairytale:" an analysis of gendered language used to describe fertilization in science textbooks from middle school to medical school

NASA Astrophysics Data System (ADS)

Campo-Engelstein, Lisa; Johnson, Nadia L.

2014-03-01

Emily Martin's (Signs J Women Cult Soc 16(31):485-501, 1991) article, "The Egg and the Sperm: How Science Has Constructed a Romance Based on Stereotypical Male-Female Roles," was published in Signs over 20 years ago. In this groundbreaking article, she discusses how gender roles are often projected onto reproductive biology, leading to the portrayal of eggs as passive and sperm as active. We were interested in seeing if many of her findings are still relevant today. We analyzed science textbooks from the middle school to the medical school level to determine if fertilization in human reproduction is described in gender-biased language regarding the sentence structure, amount of information provided for female and male processes/parts, and neutrality in describing female and male processes/parts. Although there has been much improvement, there is still a long way to go. Sexist language in scientific textbooks is troubling because it negatively affects both female and male students and undermines teachers' ability to teach in an accurate and gender-neutral way.

Impaired fertility in T-stock female mice after superovulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wyrobek, A J; Bishop, J B; Marchetti, F

2003-12-05

Superovulation of female mice with exogenous gonadotrophins is routinely used for increasing the number of eggs ovulated by each female in reproductive and developmental studies. We report an unusual effect of superovulation on fertilization in mice. In vivo matings of superovulated T-stock females with B6C3F1 males resulted in a 2-fold reduction (P<0.001) in the frequencies of fertilized eggs compared to control B6C3F1 matings. In addition, {approx}22 hr after mating only 15% of fertilized eggs recovered in T-stock females had reached the metaphase stage of the first cleavage division versus 87% in B6C3F1 females (P < 0.0001). Matings with T-stock malesmore » did not improve the reproductive performance of T-stock females. To investigate the possible cause(s) for the impaired fertilization and zygotic development, the experiments were repeated using in vitro fertilization. Under these conditions, the frequencies of fertilized eggs were not different in superovulated T-stock and B6C3F1 females (51.7% {+-} 6.0 and 64.5% {+-}3.8, P=0.10). There was a 7-fold increase in the frequencies of fertilized T-stock eggs that completed the first cell cycle of development after in vitro versus in vivo fertilization. These results rule out an intrinsic deficiency of the T-stock oocyte as the main reason for the impaired fertility after in vivo matings and suggest that superovulation of T-stock females induces a hostile oviductal and uterine environment with dramatic effects on fertilization and zygotic development.« less

Near-Infrared Spectroscopy and Imaging Studies of Fertilized Fish Eggs: In Vivo Monitoring of Egg Growth at the Molecular Level

NASA Astrophysics Data System (ADS)

Ishigaki, Mika; Kawasaki, Shoya; Ishikawa, Daitaro; Ozaki, Yukihiro

2016-01-01

In this work, the growth of fertilized Japanese medaka (Oryzias latipes) eggs was monitored in vivo at the molecular level using near-infrared (NIR) spectroscopy and NIR imaging. NIR spectra were recorded noninvasively for three major parts of a fertilized medaka egg, the embryonic body, the oil droplets, and the yolk, from the first day after fertilization to the day before hatching. Principal component analysis (PCA) revealed that water, protein, and lipid contents in the egg yolk and oil droplets changed significantly just before hatching. The ratio of the characteristic peaks due to proteins and lipids in the second derivative spectra suggested that the relative concentration of proteins to lipids was constant in the egg yolk, while it dramatically increased just before hatching in the oil droplets. Furthermore, linear discriminant analysis (LDA) predicted the hatching possibility on the next day with 100% and 99.3% accuracy for yolk and oil droplets data, respectively. Two types of NIR images were developed in situ using the band intensities of the lipids and proteins in the second derivative spectra. The egg’s protein and lipid content was successfully visualized noninvasively. This technique should enable noninvasive quality testing of fertilized eggs in the future.

Unfertilized frog eggs die by apoptosis following meiotic exit

PubMed Central

2011-01-01

Background A characteristic feature of frog reproduction is external fertilization accomplished outside the female's body. Mature fertilization-competent frog eggs are arrested at the meiotic metaphase II with high activity of the key meiotic regulators, maturation promoting factor (MPF) and cytostatic factor (CSF), awaiting fertilization. If the eggs are not fertilized within several hours of ovulation, they deteriorate and ultimately die by as yet unknown mechanism. Results Here, we report that the vast majority of naturally laid unfertilized eggs of the African clawed frog Xenopus laevis spontaneously exit metaphase arrest under various environmental conditions and degrade by a well-defined apoptotic process within 48 hours after ovulation. The main features of this process include cytochrome c release, caspase activation, ATP depletion, increase of ADP/ATP ratio, apoptotic nuclear morphology, progressive intracellular acidification, and egg swelling. Meiotic exit seems to be a prerequisite for execution of the apoptotic program, since (i) it precedes apoptosis, (ii) apoptotic events cannot be observed in the eggs maintaining high activity of MPF and CSF, and (iii) apoptosis in unfertilized frog eggs is accelerated upon early meiotic exit. The apoptotic features cannot be observed in the immature prophase-arrested oocytes, however, the maturation-inducing hormone progesterone renders oocytes susceptible to apoptosis. Conclusions The study reveals that naturally laid intact frog eggs die by apoptosis if they are not fertilized. A maternal apoptotic program is evoked in frog oocytes upon maturation and executed after meiotic exit in unfertilized eggs. The meiotic exit is required for execution of the apoptotic program in eggs. The emerging anti-apoptotic role of meiotic metaphase arrest needs further investigation. PMID:22195698

Cryoprotective and contraceptive properties of egg yolk as an additive in rooster sperm diluents.

PubMed

Santiago-Moreno, Julián; Castaño, Cristina; Toledano-Díaz, Adolfo; Coloma, Miguel A; López-Sebastián, Antonio; Prieto, María T; Campo, Jose L

2012-12-01

The addition of chicken egg yolk to semen extenders is thought to reduce the fertilizing potential of rooster spermatozoa--but not (or at least not as much) that of other avian species. The aim of the present study was to determine whether quail egg yolk, a novel extender additive, provides advantages over chicken egg yolk in the cryopreservation of rooster spermatozoa. Experiments were also performed to determine whether the harmful effect of egg yolk occurs during cryopreservation or during fertilization after artificial insemination. Heterospermic rooster semen samples were divided into aliquots and cooled in a polyvinylpyrrolidone-based medium containing 15% chicken egg yolk, 15% quail egg yolk or no egg yolk at all. The viability of spermatozoa of cooled samples (5 °C) without egg yolk were less viable (P<0.01) than those of samples containing either type of egg yolk. The same aliquots were then cryopreserved for 15 days. Thawed spermatozoa preserved without egg yolk showed lower motility (P<0.001) and viability (P<0.001) than those in samples diluted with either type of egg yolk extender. No eggs were fertilized when hens were inseminated with semen that had been diluted with chicken egg yolk. The fertilization rate was only slightly higher when sperm diluted with quail egg yolk was used (1.5%). The best results were obtained when no egg yolk was used (13.8%). These results show that the addition of egg yolk of either type protects rooster sperm cells against cold shock and during freezing and thawing, but exerts a contraceptive effect in the genital tract of the hen. Copyright © 2012 Elsevier Inc. All rights reserved.

The effects of ingested petroleum on oviposition and some aspects of reproduction in experimental colonies of mallard ducks (Anas platyrhynchos)

USGS Publications Warehouse

Holmes, W.N.; Cavanaugh, K.P.; Cronshaw, J.

1978-01-01

Compared to unmated mallard ducks fed an uncontaminated diet, unmated birds given food contaminated with 3 ml South Louisiana crude oil per 100 g dry weight showed an 84% decline in the daily rate of oviposition, a 33% decrease in egg-shell thickness and at autopsy more than 82% of the ovarian mass consisted of atretic follicles. Similar studies on groups of mated females showed that although the addition of 1 ml South Louisiana crude oil/100 g dry food had no effect on the daily rate of oviposition, none of the eggs had been fertilized while a concentration of 3 ml South Louisiana crude oil/100 g dry food suppressed the daily rate of oviposition significantly. Less than 25% of these eggs had been fertilized and only 40% of the fertilized eggs yielded viable ducklings. In both of these groups of mated birds, normal patterns of oviposition, fertilization and hatchability were restored after removal of petroleum from the diet. The addition of 1 ml Kuwait crude oil/100 g dry food had no effect on the rate of oviposition, the incidence of fertility or the hatchability of the fertilized eggs. The addition of 3 ml oil/100 g dry food completely abolished oviposition, but a normal rate of oviposition was restored when the concentration of the crude oil was reduced from 3 to 1 ml/100 g dry food. However, the incidence of fertilization remained low and none of the fertilized eggs gave rise to viable ducklings. Kuwait crude oil had no effect on shell thickness.

Nutrient Status and Contamination Risks from Digested Pig Slurry Applied on a Vegetable Crops Field

PubMed Central

Zhang, Shaohui; Hua, Yumei; Deng, Liangwei

2016-01-01

The effects of applied digested pig slurry on a vegetable crops field were studied. The study included a 3-year investigation on nutrient characteristics, heavy metals contamination and hygienic risks of a vegetable crops field in Wuhan, China. The results showed that, after anaerobic digestion, abundant N, P and K remained in the digested pig slurry while fecal coliforms, ascaris eggs, schistosoma eggs and hookworm eggs were highly reduced. High Cr, Zn and Cu contents in the digested pig slurry were found in spring. Digested pig slurry application to the vegetable crops field led to improved soil fertility. Plant-available P in the fertilized soils increased due to considerable increase in total P content and decrease in low-availability P fraction. The As content in the fertilized soils increased slightly but significantly (p = 0.003) compared with control. The Hg, Zn, Cr, Cd, Pb, and Cu contents in the fertilized soils did not exceed the maximum permissible contents for vegetable crops soils in China. However, high Zn accumulation should be of concern due to repeated applications of digested pig slurry. No fecal coliforms, ascaris eggs, schistosoma eggs or hookworm eggs were detected in the fertilized soils. PMID:27058548

The Sperm-surface glycoprotein, SGP, is necessary for fertilization in the frog, Xenopus laevis.

PubMed

Nagai, Keita; Ishida, Takuya; Hashimoto, Takafumi; Harada, Yuichirou; Ueno, Shuichi; Ueda, Yasushi; Kubo, Hideo; Iwao, Yasuhiro

2009-06-01

To identify a molecule involved in sperm-egg plasma membrane binding at fertilization, a monoclonal antibody against a sperm-surface glycoprotein (SGP) was obtained by immunizing mice with a sperm membrane fraction of the frog, Xenopus laevis, followed by screening of the culture supernatants based on their inhibitory activity against fertilization. The fertilization of both jellied and denuded eggs was effectively inhibited by pretreatment of sperm with intact anti-SGP antibody as well as its Fab fragment, indicating that the antibody recognizes a molecule on the sperm's surface that is necessary for fertilization. On Western blots, the anti-SGP antibody recognized large molecules, with molecular masses of 65-150 kDa and minor smaller molecules with masses of 20-28 kDa in the sperm membrane vesicles. SGP was distributed over nearly the entire surface of the sperm, probably as an integral membrane protein in close association with microfilaments. More membrane vesicles containing SGP bound to the surface were found in the animal hemisphere compared with the vegetal hemisphere in unfertilized eggs, but the vesicle-binding was not observed in fertilized eggs. These results indicate that SGP mediates sperm-egg membrane binding and is responsible for the establishment of fertilization in Xenopus.

Influence of clinostat rotation on fertilized amphibian egg pattern specification

NASA Technical Reports Server (NTRS)

Neff, A. W.; Smith, R. C.; Malacinski, G. M.; Chung, H.-M.

1984-01-01

Pattern specification in fertile Xenopus eggs rotated on horizontal clinostats was monitored with respect to primary embryonic axis formation, subsequent morphogenesis, and compartmentalization of the cytoplasm. At the speeds of 1 to 24 rpm (which are believed to simulate microgravity) a large percentage of eggs developed normal axial structures. Eggs clinostated at 12 rpm showed a randomization of dorsal/ventral polarity. The cytoplasmic compartments showed some clinostat effects but no abnormal mixing, disruption or dislocation of compartments. It is predicted that Xenopus eggs fertilized and allowed to develop in space will retain normal cytoplasmic density compartments, establish primary axes and undergo normal morphogenesis in space. Their dorsal/ventral polarity may not, however, be determined by the sperm entrance site (as is the case for 1 g eggs).

Organic and inorganic selenium in Aseel chicken diets: Effect on hatching traits.

PubMed

Khan, M T; Mahmud, A; Zahoor, I; Javed, K

2017-05-01

A study was conducted to evaluate the effect of dietary selenium (Se) sources (organic and inorganic Se at 0.30 ppm and basal diet at 0 ppm level of supplemented Se) on hatching traits in four varieties of Aseel chicken, Lakha, Mushki, Peshawari, and Mianwali. In total, 84 adult molted hens (50 wk old), 21 from each variety, were randomly assigned to 12 treatment groups in a 3 (Se diets) × 4 (Aseel varieties) factorial arrangement under a randomized complete block design. Each treatment was replicated 7 times with individual hens in each. Settable egg, fertility, hatch of fertile eggs, hatchability, A-grade chick, and embryonic mortality parameters were evaluated. The results indicated that the birds fed an organic Se supplemented diet had greater (P < 0.05) settable eggs, fertility, hatch of fertile eggs, hatchability, and A-grade chicks and reduced embryonic mortality than those fed inorganic or no Se. Among varieties, Mushki had lower (P < 0.05) fertility, hatch of fertile eggs, hatchability, and A-grade chicks than rest of three varieties. Interaction of Se sources and varieties indicated that dietary organic Se supplementation improved (P < 0.05) hatch of fertile eggs in Peshawari and Mianwali, whereas hatchability only in Peshawari variety and reduced embryonic mortality in Mianwali. It was concluded that dietary supplementation of organic Se could be used to improve hatching traits as well as reduce embryonic mortality in native Aseel chicken. © 2016 Poultry Science Association Inc.

Albumin is synthesized in epididymis and aggregates in a high molecular mass glycoprotein complex involved in sperm-egg fertilization.

PubMed

Arroteia, Kélen Fabíola; Barbieri, Mainara Ferreira; Souza, Gustavo Henrique Martins Ferreira; Tanaka, Hiromitsu; Eberlin, Marcos Nogueira; Hyslop, Stephen; Alvares, Lúcia Elvira; Pereira, Luís Antonio Violin Dias

2014-01-01

The epididymis has an important role in the maturation of sperm for fertilization, but little is known about the epididymal molecules involved in sperm modifications during this process. We have previously described the expression pattern for an antigen in epididymal epithelial cells that reacts with the monoclonal antibody (mAb) TRA 54. Immunohistochemical and immunoblotting analyses suggest that the epitope of the epididymal antigen probably involves a sugar moiety that is released into the epididymal lumen in an androgen-dependent manner and subsequently binds to luminal sperm. Using column chromatography, SDS-PAGE with in situ digestion and mass spectrometry, we have identified the protein recognized by mAb TRA 54 in mouse epididymal epithelial cells. The ∼65 kDa protein is part of a high molecular mass complex (∼260 kDa) that is also present in the sperm acrosomal vesicle and is completely released after the acrosomal reaction. The amino acid sequence of the protein corresponded to that of albumin. Immunoprecipitates with anti-albumin antibody contained the antigen recognized by mAb TRA 54, indicating that the epididymal molecule recognized by mAb TRA 54 is albumin. RT-PCR detected albumin mRNA in the epididymis and fertilization assays in vitro showed that the glycoprotein complex containing albumin was involved in the ability of sperm to recognize and penetrate the egg zona pellucida. Together, these results indicate that epididymal-derived albumin participates in the formation of a high molecular mass glycoprotein complex that has an important role in egg fertilization.

Long term storage of bee semen – A six month assessment of cryopreserved semen quality using motility as an index

USDA-ARS?s Scientific Manuscript database

Bee (Apis mellifera Linn.) spermatozoa is known for its ability to remain viable for at the least two years within the spermatheca as attested to by the queens’ continued laying of fertile eggs without remating over two to three (Woyke 1960; Winston 1987). However, the semen collected from the dron...

The first report of gynandromorphy in termites (Isoptera; Kalotermitidae; Neotermes koshunensis).

PubMed

Miyaguni, Yasushi; Nozaki, Tomonari; Yashiro, Toshihisa

2017-08-01

This is the first report of gynandromorphy in Isoptera. An Asian dry-wood termite, Neotermes koshunensis (Shiraki) [Kalotermitidae], possessing both male and female phenotypic characteristics, was found on Okinawa Island, Japan. This deformed individual showed morphological and anatomical hermaphroditism in the abdomen. The right side of the seventh sternite was the female form and contained an ovary, while the left side was the male form and contained a testis. Genotypic analysis revealed that this individual was a genotypic bilateral chimera. These results suggested that the termite was a bilateral gynandromorph with a male left side and a female right side. As reported previously in other insects, double fertilization (by two sperms, one with an X and one with a Y chromosome) of a binucleate egg is the most likely mechanism that generated this genotypic bilateral chimera. N. koshunensis has the ability to reproduce through parthenogenesis, in which the secondary polar body is likely to be used for nuclear phase recovery. If the second polar body in this mechanism has high fertility and healthy embryogenic potential, like an egg nucleus, some of gynandromorphs might be produced by a side effect of parthenogenetic ability.

The first report of gynandromorphy in termites (Isoptera; Kalotermitidae; Neotermes koshunensis)

NASA Astrophysics Data System (ADS)

Miyaguni, Yasushi; Nozaki, Tomonari; Yashiro, Toshihisa

2017-08-01

This is the first report of gynandromorphy in Isoptera. An Asian dry-wood termite, Neotermes koshunensis (Shiraki) [Kalotermitidae], possessing both male and female phenotypic characteristics, was found on Okinawa Island, Japan. This deformed individual showed morphological and anatomical hermaphroditism in the abdomen. The right side of the seventh sternite was the female form and contained an ovary, while the left side was the male form and contained a testis. Genotypic analysis revealed that this individual was a genotypic bilateral chimera. These results suggested that the termite was a bilateral gynandromorph with a male left side and a female right side. As reported previously in other insects, double fertilization (by two sperms, one with an X and one with a Y chromosome) of a binucleate egg is the most likely mechanism that generated this genotypic bilateral chimera. N. koshunensis has the ability to reproduce through parthenogenesis, in which the secondary polar body is likely to be used for nuclear phase recovery. If the second polar body in this mechanism has high fertility and healthy embryogenic potential, like an egg nucleus, some of gynandromorphs might be produced by a side effect of parthenogenetic ability.

The influence of ph and waterborne metals on egg fertilization of the blue mussel (Mytilus edulis), the oyster (Crassostrea gigas) and the sea urchin (Paracentrotus lividus).

PubMed

Riba, Inmaculada; Gabrielyan, Bardukh; Khosrovyan, Alla; Luque, Angel; Del Valls, T Angel

2016-07-01

This study evaluated the combined effect of pH and metals on the egg fertilization process of two estuarine species, the blue mussel (Mytilus edulis), the oyster (Crassostrea gigas) and a marine species, the sea urchin (Paracentrotus lividus). The success of egg fertilization was examined after exposure of gametes to sediment extracts of various degrees of contamination at pH 6.0, 6.5, 7.0, 7.5 and 8.0. At the pH levels from 6.5 to 8.0, the egg fertilization of the different species demonstrated different sensitivity to metal and/or acidic exposure. In all species, the results revealed that egg fertilization was almost completely inhibited at pH 6.0. The egg fertilization of the blue mussel M. edulis was the least sensitive to the exposure while that of the sea urchin P. lividus demonstrated a concentration-dependent response to the pH levels from 6.5 to 8.0. The results of this study revealed that acidity increased the concentration of several metal ions (Cr, Ni, Cu, Zn, Cd, and Pb) but reduced its availability to the organisms, probably related to the reactivity of the ions with most non-metals or to the competition among metals and other waterborne constituents.

Natural fertility in whooping cranes and Mississippi sandhill cranes at Patuxent Wildlife Research Center

USGS Publications Warehouse

Nicolich, Jane M.; Gee, G.F.; Ellis, D.H.; Hereford, Scott G.

2001-01-01

The first fertile whooping crane (Grus americana; WC) egg produced through natural breeding at Patuxent Wildlife Research Center (Patuxent) was laid in 1991. Prior to that time, all fertile whooping crane eggs were the result of artificial insemination. Since 1991, eight different whooping crane pairs at Patuxent have produced fertile eggs through natural breeding. Mean fertility averages over years for each pair range from 40% to 93%. Fertility rates for each pair also vary greatly between years, from 0% to 100% but the causes of the variance are unknown. Experiences with natural fertility in Mississippi sandhill cranes (G. canadensis pulla; MSC) have been similar. Annual natural fertility rates averaged from 21% to 89% and fertility averages for each of 7 pairs also varied greatly between years. Rearing methods have not determined success in natural breeding for either species. Both hand-reared and parent-reared pairs have been fertile. Wing condition, however, has been an important factor affecting natural fertility. Becausce artificial insemination (AI) generally results in higher fertility rates than natural breeding, Al should continue for some pairs.

An intact acrosome is required for the chemotactic response to progesterone in mouse spermatozoa.

PubMed

Guidobaldi, Hector A; Hirohashi, Noritaka; Cubilla, Marisa; Buffone, Mariano G; Giojalas, Laura C

2017-04-01

Mammalian sperm become fertilization-competent in the oviduct, during a process known as capacitation that involves the acquisition of the ability to exocytose the acrosome but also the chemotactic responses-both of which contribute to successful fertilization. Chemotaxis is used by spermatozoa to orient and to locate the egg; the acrosome reaction facilitates sperm binding to and fusing with the egg membrane. Mammalian spermatozoa are able to sense picomolar concentrations of progesterone, which drives chemotactic behavior. The state of the acrosome during the chemotactic response, however, is unknown. Genetically modified mouse spermatozoa were employed in a chemotaxis assay under fluorescence microscopy to evaluate their acrosome status while swimming, allowing us to elucidate the acrosome integrity of sperm responding to progesterone-induced chemotaxis. We first showed that wild-type mouse spermatozoa chemotactically respond to a gradient of progesterone, and that the genetic modifications employed do not affect the chemotactic behavior of sperm to progesterone. Next, we found that acrosome-intact, but not acrosome-reacted, spermatozoa orient and respond to picomolar concentrations of progesterone and that chemotaxis normally occurs prior to the acrosome reaction. Our results suggest that premature commitment to acrosome exocytosis leads to navigation failure, so proper control and timing of the acrosome reaction is required for fertilization success and male fertility. © 2017 Wiley Periodicals, Inc.

Fertilization capacity with rainbow trout DNA-damaged sperm and embryo developmental success.

PubMed

Pérez-Cerezales, S; Martínez-Páramo, S; Beirão, J; Herráez, M P

2010-06-01

Mammalian spermatozoa undergo a strong selection process along the female tract to guarantee fertilization by good quality cells, but risks of fertilization with DNA-damaged spermatozoa have been reported. In contrast, most external fertilizers such as fish seem to have weaker selection procedures. This fact, together with their high prolificacy and external embryo development, indicates that fish could be useful for the study of the effects of sperm DNA damage on embryo development. We cryopreserved sperm from rainbow trout using egg yolk and low-density lipoprotein as additives to promote different rates of DNA damage. DNA fragmentation and oxidization were analyzed using comet assay with and without digestion with restriction enzymes, and fertilization trials were performed. Some embryo batches were treated with 3-aminobenzamide (3AB) to inhibit DNA repair by the poly (ADP-ribose) polymerase, which is an enzyme of the base excision repair pathway. Results showed that all the spermatozoa cryopreserved with egg yolk carried more than 10% fragmented DNA, maintaining fertilization rates of 61.1+/-2.3 but a high rate of abortions, especially during gastrulation, and only 14.5+/-4.4 hatching success. Furthermore, after 3AB treatment, hatching dropped to 3.2+/-2.2, showing that at least 10% DNA fragmentation was repaired. We conclude that trout sperm maintains its ability to fertilize in spite of having DNA damage, but that embryo survival is affected. Damage is partially repaired by the oocyte during the first cleavage. Important advantages of using rainbow trout for the study of processes related to DNA damage and repair during development have been reported.

THE MEMBRANE CAPACITANCE OF THE SEA URCHIN EGG

PubMed Central

Rothschild, Lord

1957-01-01

1. The surface of the unfertilized sea urchin egg is folded and the folds are reversibly eliminated by exposing the egg to hypotonic sea water. If the plasma membrane is outside the layer of cortical granules, unfolding may explain why the membrane capacitance per unit area decreases (and does not increase) when a sea urchin egg is put into hypotonic sea water. 2. The degree of surface folding markedly increases after fertilization, which provides an explanation for the increase in membrane capacitance per unit area observed after fertilization. 3. The percentage reduction in membrane folding in fertilized eggs after immersion in hypotonic sea water is probably sufficient to explain the decrease in membrane capacitance per unit area observed in these conditions. PMID:13416315

Simultaneous investigation of intracellular Ca2+ increase and morphological events upon fertilization in the sand dollar egg.

PubMed

Hamaguchi, Y; Hamaguchi, M S

1990-06-01

An increase in intracellular Ca2+ concentration ([Ca2+]) and morphological were simultaneously observed by epifluorescence and differential interference contrast (DIC) microscopy during fertilization of the sand dollar, Clypeaster japonicus. [Ca2+], which was detected by a Ca2+ indicator, Fluo-3, initially increased just beneath the sperm-attached site on the egg surface 8.6 sec after attachment. The increase spread into the egg as a concentric sphere to the egg center and, thereafter, propagated in the egg cytoplasm as a planar wave rather than a spherical wave. It reached the site opposite the initiation site across the egg 24.2 sec after initiation. The fertilization envelope (FE) began to elevate 10.3 sec after the initiation of the increase in [Ca2+] and 21.2 sec after sperm attachment.

Evolution of egg target size: an analysis of selection on correlated characters.

PubMed

Podolsky, R D

2001-12-01

In broadcast-spawning marine organisms, chronic sperm limitation should select for traits that improve chances of sperm-egg contact. One mechanism may involve increasing the size of the physical or chemical target for sperm. However, models of fertilization kinetics predict that increasing egg size can reduce net zygote production due to an associated decline in fecundity. An alternate method for increasing physical target size is through addition of energetically inexpensive external structures, such as the jelly coats typical of eggs in species from several phyla. In selection experiments on eggs of the echinoid Dendraster excentricus, in which sperm was used as the agent of selection, eggs with larger overall targets were favored in fertilization. Actual shifts in target size following selection matched quantitative predictions of a model that assumed fertilization was proportional to target size. Jelly volume and ovum volume, two characters that contribute to target size, were correlated both within and among females. A cross-sectional analysis of selection partitioned the independent effects of these characters on fertilization success and showed that they experience similar direct selection pressures. Coupled with data on relative organic costs of the two materials, these results suggest that, under conditions where fertilization is limited by egg target size, selection should favor investment in low-cost accessory structures and may have a relatively weak effect on the evolution of ovum size.

Mouse SLLP1, a sperm lysozyme-like protein involved in sperm-egg binding and fertilization.

PubMed

Herrero, María Belén; Mandal, Arabinda; Digilio, Laura C; Coonrod, Scott A; Maier, Bernhard; Herr, John C

2005-08-01

This study demonstrates the retention of mouse sperm lysozyme-like protein (mSLLP1) in the equatorial segment of spermatozoa following the acrosome reaction and a role for mSLLP1 in sperm-egg binding and fertilization. Treatment of cumulus intact oocytes with either recmSLLP1 or its antiserum resulted in a significant (P < or = 0.05) inhibition of fertilization. Co-incubation of zona-free mouse oocytes with capacitated mouse spermatozoa in the presence of varying concentrations of anti-recmSLLP1 serum or recmSLLP1 also inhibited sperm-oolemma binding. A complete inhibition of binding and fusion of spermatozoa to the oocyte occurred at 12.5 muM concentration of recmSLLP1, while conventional chicken and human lysozymes did not block sperm-egg binding. mSLLP1 showed receptor sites in the perivitelline space as well as on the microvillar region of the egg plasma membrane. The retention of mSLLP1 in the equatorial segment of acrosome-reacted sperm, the inhibitory effects of both recmSLLP1 and antibodies to SLLP1 on in vitro fertilization with both cumulus intact and zona-free eggs, and the definition of complementary SLLP1-binding sites on the egg plasma membrane together support the hypothesis that a c lysozyme-like protein is involved in the binding of spermatozoa to the egg plasma membrane during fertilization.

Delayed fertilization of anuran amphibian (Xenopus) eggs leads to reduced numbers of primordial germ cells

NASA Technical Reports Server (NTRS)

Wakahara, M.; Neff, A. W.; Malacinski, G. M.

1984-01-01

Several media were tested for the extent to which they promoted high fertilization efficiencies in ovulated, stripped Xenopus eggs. One medium was selected for maintaining eggs in a 'delayed fertilization' (DelF) condition. DelF eggs displayed several unusual characteristics, including shift of the center of gravity, prominent sperm entrance site, and occasional polyspermy. The frequency of normal pattern formation varied according to the length of time eggs were maintained in the DelF condition. Various developmental abnormalities were observed during gastrulation, neurulation, and organogenesis. Most abnormalities appeared, however, to be related to morphogenesis of the endoderm. Primordial germ cell (PGC) development was examined in DelF eggs which displayed normal external morphological features at the swimming tadpole stage. PGC counts were usually normal in short-duration (eg, 5 hr) DelF eggs, but frequently substantially reduced or completely diminished in longer-duration (eg, 25h) tadpoles. Six spawnings were compared and shown to exhibit considerable variability in fertility, morphogenesis, and PGC development. Yolk platelet shifts and developmental parameters were examined in two additional spawnings. The subcortical cytoplasm in which the germ plasm is normally localized appeared to be disrupted in longer duration DelF eggs. That observation may account for low PGC counts in DelF tadpoles.

Experiments with the Viability of Chicken Eggs

ERIC Educational Resources Information Center

Garigliano, Leonard J.

1975-01-01

Presents the results of an experiment designed to test two hypotheses: (1) a delay of two weeks at room temperature will have no effect on the viability of fertile chicken eggs and (2) refrigeration will have no effect on the viability of fertile chicken eggs. Experimenters were the author and two ninth-grade students. (PEB)

Paternity in horseshoe crabs when spawning in multiple-male groups.

PubMed

Brockmann; Nguyen; Potts

2000-12-01

Unpaired or satellite male horseshoe crabs, Limulus polyphemus, are attracted to and often form a group around a pair (a female with an attached male) that is nesting in the high intertidal zone. These males are engaged in sperm competition. We observed nesting pairs and their associated satellites in the wild, collected and reared their eggs and used genetic markers to examine paternity. We found that the unpaired, satellite males are highly successful at fertilizing eggs; two satellites can leave the attached male with few fertilizations. Two satellites together are each as successful as one spawning with a pair. A satellite's location around the female greatly affects his success, and males compete for access to a position over the dorsal canal between the prosoma and opisthosoma of the female and under the front margin of the paired male where they are most likely to fertilize eggs. Although eggs and sperm retain their viability for some time after spawning, nearly all eggs are fertilized by the satellites that are around the nesting pair at the time of egg laying and by the attached male. A number of factors including beach current, female size and male behaviour affect the outcome of sperm competition in this externally fertilizing species. Copyright 2000 The Association for the Study of Animal Behaviour.

Toxicity of pesticide and fertilizer mixtures simulating corn production to eggs of snapping turtles (Chelydra serpentina).

PubMed

de Solla, Shane Raymond; Martin, Pamela Anne; Mikoda, Paul

2011-09-15

Many reptiles oviposit in soils associated with agricultural landscapes. We evaluated the toxicity of a pesticide and fertilizer regime similar to those used in corn production in Ontario on the survivorship of exposed snapping turtle (Chelydra serpentina) eggs. The herbicides atrazine, dimethenamid, and glyphosate, the pyrethroid insecticide tefluthrin, and the fertilizer ammonia, were applied to clean soil, both as partial mixtures within chemical classes, as well as complete mixtures. Eggs were incubated in the soil in a garden plot in which these mixtures were applied at a typical field application rate, and higher rates. Otherwise, the eggs were unmanipulated and were subject to ambient temperature and weather conditions. Eggs were also exposed at male producing temperatures in the laboratory in covered bins in the same soil, where there was less opportunity for loss through volatilization or leaching. Egg mortality was 100% at 10× the typical field application rate of the complete mixture, both with and without tefluthrin. At typical field application rates, hatching success ranged between 91.7 and 95.8%. Eggs exposed only to herbicides were not negatively affected at any application rates. Although fertilizer treatments at typical field application rates did not affect eggs, mortality was remarkably higher at three times this rate, and 100% at higher rates. The frequency of deformities of hatchlings was elevated at the highest application rate of the insecticide tefluthrin. The majority of the toxicity of the mixture was not due to the herbicides or insecticide, but was due to the ammonia fertilizer. At typical field application rates, the chemical regime associated with corn production does not appear to have any detrimental impacts upon turtle egg development; however toxicity dramatically increases if this threshold is passed. Copyright © 2011. Published by Elsevier B.V.

Cortical Isolation from Xenopus laevis Oocytes and Eggs.

PubMed

Sive, Hazel L; Grainger, Robert M; Harland, Richard M

2007-06-01

INTRODUCTIONIn Xenopus laevis, the cortex is the layer of gelatinous cytoplasm that lies just below the plasma membrane of the egg. Rotation of the cortex relative to the deeper cytoplasm soon after fertilization is intimately linked to normal dorsal axis specification. The cortex can be dissected from the egg to analyze its composition and activity or to clone associated RNAs. This protocol describes a procedure for isolating the vegetal cortex of the fertilized egg.

Fertilization and development of eggs of the South African clawed toad, Xenopus laevis, on sounding rockets in space

NASA Astrophysics Data System (ADS)

Ubbels, Geertje A.; Berendsen, Willem; Kerkvliet, Sonja; Narraway, Jenny

Egg rotation and centrifugation experiments strongly suggest a role for gravity in the determination of the spatial structure of amphibian embryos. Decisive experiments can only be made in Space. Eggs of Xenopus laevis, the South African clawed toad, were the first vertebrate eggs which were successfully fertilized on Sounding Rockets in Space. Unfixed, newly fertilized eggs survived reentry, and a reasonable number showed a seemingly normal gastrulation but died between gastrulation and neurulation. Only a few reached the larval stage, but these developed abnormally. In the future, we inted to test whether this abnormal morphogenesis is due to reentry perturbations, or due to a real microgravity effect, through perturbation of the reinitiation of meiosis and other processes, or started by later sperm penetration.

Fertilization and development of eggs of the South African clawed toad, Xenopus laevis, on sounding rockets in space.

PubMed

Ubbels, G A; Berendsen, W; Kerkvliet, S; Narraway, J

1992-01-01

Egg rotation and centrifugation experiments strongly suggest a role for gravity in the determination of the spatial structure of amphibian embryos. Decisive experiments can only be made in Space. Eggs of Xenopus laevis, the South African clawed toad, were the first vertebrate eggs which were successfully fertilized on Sounding Rockets in Space. Unfixed, newly fertilized eggs survived reentry, and a reasonable number showed a seemingly normal gastrulation but died between gastrulation and neurulation. Only a few reached the larval stage, but these developed abnormally. In the future, we intend to test whether this abnormal morphogenesis is due to reentry perturbations, or due to a real microgravity effect, through perturbation of the reinitiation of meiosis and other processes, or started by later sperm penetration.

The cell biology of mammalian fertilization.

PubMed

Okabe, Masaru

2013-11-01

Fertilization is the process by which eggs and spermatozoa interact, achieve mutual recognition, and fuse to create a zygote, which then develops to form a new individual, thus allowing for the continuity of a species. Despite numerous studies on mammalian fertilization, the molecular mechanisms underpinning the fertilization event remain largely unknown. However, as I summarize here, recent work using both gene-manipulated animals and in vitro studies has begun to elucidate essential sperm and egg molecules and to establish predictive models of successful fertilization.

Fertilization Mechanisms in Flowering Plants

PubMed Central

Dresselhaus, Thomas; Sprunck, Stefanie; Wessel, Gary M.

2016-01-01

Compared to the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells). Sperm cell release from the pollen tube occurs after intensive communication between the pollen tube cell and the receptive synergid, culminating in the lysis of both interaction partners. Following release of the two sperm cells they interact and fuse with two dimorphic female gametes (egg and central cell) forming the major seed components embryo and endosperm, respectively. This process is known as double fertilization. Here we review the current understanding of the processes of sperm cell reception, gamete interaction, their pre-fertilization activation and fusion as well as the mechanisms plants use to prevent the fusion of egg cells with multiple sperm cells. The role of Ca2+ is highlighted in these various processes and comparisons are drawn between fertilization mechanisms in flowering plants and other eukaryotes including mammals. PMID:26859271

Experimental Mycoplasma gallisepticum infections in captive-reared wild turkeys

USGS Publications Warehouse

Rocke, Tonie E.; Yuill, Thomas M.; Amundson, Terry E.

1988-01-01

The effects of Mycoplasma gallisepticum (MG) infections on egg production, fertility, and hatchability were studied in captive-reared wild turkeys (Meleagris gallopavo). Three groups of adult birds, each consisting of four hens and two toms, were exposed to MG by the respiratory route at the beginning of their breeding season. Fourteen control birds received sterile growth medium. Although no mortality of infected or control birds occurred, egg production during the first breeding season after infection was reduced. The mean number of eggs/hen/day produced by infected groups the first breeding season postexposure (PE) was significantly lower than the control value. The mean number of eggs produced daily by the same hens 1 yr later was unaffected by MG infection. The pecentage of fertile eggs produced by infected groups was slightly reduced in both the first and second breeding seasons PE. Hatchability of fertile eggs from infected hens was significantly lower than eggs from control hens. Productivity may be impaired if MG infections occur in free-ranging wild turkey populations.

Microencapsulation of bovine spermatozoa for use in artificial insemination: a review.

PubMed

Nebel, R L; Vishwanath, R; McMillan, W H; Saacke, R G

1993-01-01

A technique for microencapsulation of bovine spermatozoa has been developed with minimal spermatozoal injury and thus of potential use in artificial insemination. The polymers poly-l-lysine, polyvinylamine and protamine sulfate have proven best for membranes. Encapsulation has been successful with capsules ranging in size from 0.75 to 1.5 mm, and with sperm concentrations from 45 to 180 x 10(6) cells mL-1. Successful extenders include CUE, CAPROGEN, and egg yolk-citrate-glycerol (maximum 10% v/v egg yolk for normal capsular shape). Capsule fragility (ability to rupture under ageing and physical stress) is negatively related to membrane thickness which ranges from 1.92 to 5.32 microns (depending on the concentration of polymer used) and positively related to concentration of sperm encapsulated. Heterospermic studies have shown that encapsulated sperm are capable of fertilization in vivo, but are at a disadvantage to unencapsulated sperm when cows are inseminated at conventional times. Uterine retention of inseminates is favoured by capsules having a 'sticky' membrane. Using current procedures, preliminary homospermic fertility studies indicate that sperm encapsulated with poly-l-lysine or protamine sulfate may achieve normal fertility.

Mlh1 is required for female fertility in Drosophila melanogaster: An outcome of effects on meiotic crossing over, ovarian follicles and egg activation.

PubMed

Vimal, Divya; Kumar, Saurabh; Pandey, Ashutosh; Sharma, Divya; Saini, Sanjay; Gupta, Snigdha; Ravi Ram, Kristipati; Chowdhuri, Debapratim Kar

2018-03-01

Mismatch repair (MMR) system, a conserved DNA repair pathway, plays crucial role in DNA recombination and is involved in gametogenesis. The impact of alterations in MMR family of proteins (bacterial MutS and MutL homologues) on mammalian fertility is well documented. However, an insight to the role of MMR in reproduction of non-mammalian organisms is limited. Hence, in the present study, we analysed the impact of mlh1 (a MutL homologue) on meiotic crossing over/recombination and fertility in a genetically tractable model, Drosophila melanogaster. Using mlh1 e00130 hypomorphic allele, we report female specific adverse reproductive outcome for reduced mlh1 in Drosophila: mlh1 e00130 homozygous females had severely reduced fertility while males were fertile. Further, mlh1 e00130 females contained small ovaries with large number of early stages as well as significantly reduced mature oocytes, and laid fewer eggs, indicating discrepancies in egg production and ovulation. These observations contrast the sex independent and/or male specific sterility and normal follicular development as well as ovulation reported so far for MMR family proteins in mammals. However, analogous to the role(s) of mlh1 in meiotic crossing over and DNA repair processes underlying mammalian fertility, ovarian follicles from mlh1 e00130 females contained significantly increased DNA double strand breaks (DSBs) and reduced synaptonemal complex foci. In addition, large proportion of fertilized eggs display discrepancies in egg activation and fail to proceed beyond stage 5 of embryogenesis. Hence, reduction of the Mlh1 protein level leads to defective oocytes that fail to complete embryogenesis after fertilization thereby reducing female fertility. Copyright © 2017 Elsevier GmbH. All rights reserved.

Accessory sperm as an indication of fertilizing ability of rabbit spermatozoa frozen in egg yolk-acetamide with detergent.

PubMed

Arriola, J; Foote, R H

2001-01-01

Many factors besides initial semen quality affect fertilization rates as sperm interact with the environment of the female reproductive tract. One of these factors is sperm transport, which can be evaluated by accessory sperm counts. Dutch rabbits were used to test the effects on sperm transport, fertilization, and production of young when sodium and triethanolamine lauryl sulfate (STLS) detergent was added to a medium for sperm cryopreservation. When STLS was added in 10 concentrations ranging from 0% to 2.0% (vol/vol) to an egg yolk-acetamide semen extender, optimal post-thaw motility of rabbit sperm occurred when 0.2% to 0.7% STLS was included. However, when 0%, 0.2%, and 0.7% STLS was included to cryopreserve sperm used for insemination, the fertilization rates were 95%, 68%, and 75%, and the corresponding mean numbers of accessory sperm per embryo were 13.1, 1.7, and 0.4 (P < .05). In another experiment, increasing the acetamide concentration from 0.75 M to 1.25 M decreased fertilization rates from 66% to 35%, and was associated with 4.5 and 0.6 accessory sperm per embryo (P < .05). In the final experiment, 48 does inseminated with sperm cryopreserved with 0%, 0.35%, and 0.70% STLS were allowed to produce young. Corresponding pregnancy rates were 56%, 56%, and 31% (P < .05), and litter sizes were 5.6, 4.1, and 4.2 (P > .05). In these studies, low concentrations of STLS improved motility of frozen-thawed sperm, but fertilization and pregnancy rates were reduced. Sperm transport was correspondingly reduced, and the accessory sperm count provided a reliable measure of the effect of STLS on fertility in contrast to the assessment of the percentage of motile sperm.

Hatchability tests with eggs from captive wood ducks

USGS Publications Warehouse

Doty, H.A.

1972-01-01

The effect of diet and artificial incubation on fertility and hatchability of wood duck (Aix sponsa) eggs and survival of young was measured. Hatchability of eggs from hens fed a diet containing 37 percent protein was increased significantly (P <0.05) over that of hens fed a diet containing 17 percent protein. Hatchability was also significantly (P<0.005) greater for eggs incubated 10 days under hens before being placed in an incubator than for eggs placed in an incubator for the entire period. Ducklings that hatched from naturally started incubation survived at a much higher rate (P<0.001). Egg fertility was not affected by the diets.

Effects of Temperature on In Vitro Short-Term Storage of Sterlet Sturgeon (Acipenser Ruthenus) Ova.

PubMed

Linhart, O; Shelton, W L; Tučková, V; Rodina, M; Siddique, Mam

2016-02-01

Artificial propagation of sturgeons is becoming increasingly important for recovery efforts as well as for commercial production. Sterlet Acipenser ruthenus is a common Eurasian sturgeon with a small body size and one of the fastest reproductive cycles among the sturgeons. The practical question being addressed in this study was how long fertilization of ovulated eggs can be delayed without substantially reducing the hatching rate, and an ancillary question is under what' temperature conditions do eggs retain good quality. Broodstock were injected with homogenized carp pituitary extract (CPE); ovulated eggs from three females were allocated to various treatment groups for temperature storage (control, 7°C, 11°C, 15°C and 19°C) until fertilized. Storage times at the regulated temperatures prior to fertilization were for 2.5, 5.0, 7.5 and 10.0 h. After the selected storage times in ovarian fluid, eggs were fertilized and transferred to incubation cages and then they were counted. Three replicates were allocated to each storage period and temperature. Hatched larvae were counted at 7-day post-fertilization. We found that sterlet eggs do not need to be fertilized immediately after collection. Reasonably good quality was retained for several hours if temperature conditions are fairly cool and stable. Eggs retained good quality when stored at 7°C and 11°C for up to 10 h with 54.1 ± 2.9 to 69.9 ± 7.9% hatching success, but egg quality was significantly reduced after 5-h storage at 19°C (p < 0.01) and 7.5-h storage at 15°C (p < 0.05) compared to cooler temperatures. Uniform temperatures between 7°C and 11°C can be considered as appropriate for storage of eggs in ovarian fluid for up to 10 h. This information can have practical application to routine hatchery practice for acipenserids, as well as for certain research protocols. © 2015 Blackwell Verlag GmbH.

Factors and pathways involved in capacitation: how are they regulated?

PubMed Central

Jin, Shi-Kai; Yang, Wan-Xi

2017-01-01

In mammals, fertilization occurs via a comprehensive progression of events. Freshly ejaculated sperm have yet to acquire progressive motility or fertilization ability. They must first undergo a series of biochemical and physiological changes, collectively known as capacitation. Capacitation is a significant prerequisite to fertilization. During the process of capacitation, changes in membrane properties, intracellular ion concentration and the activities of enzymes, together with other protein modifications, induce multiple signaling events and pathways in defined media in vitro or in the female reproductive tract in vivo. These, in turn, stimulate the acrosome reaction and prepare spermatozoa for penetration of the egg zona pellucida prior to fertilization. In the present review, we conclude all mainstream factors and pathways regulate capacitation and highlight their crosstalk. We also summarize the relationship between capacitation and assisted reproductive technology or human disease. In the end, we sum up the open questions and future avenues in this field. PMID:27690295

Alteration of the Cortical Actin Cytoskeleton Deregulates Ca2+ Signaling, Monospermic Fertilization, and Sperm Entry

PubMed Central

Puppo, A.; Chun, Jong T.; Gragnaniello, Giovanni; Garante, Ezio; Santella, Luigia

2008-01-01

Background When preparing for fertilization, oocytes undergo meiotic maturation during which structural changes occur in the endoplasmic reticulum (ER) that lead to a more efficient calcium response. During meiotic maturation and subsequent fertilization, the actin cytoskeleton also undergoes dramatic restructuring. We have recently observed that rearrangements of the actin cytoskeleton induced by actin-depolymerizing agents, or by actin-binding proteins, strongly modulate intracellular calcium (Ca2+) signals during the maturation process. However, the significance of the dynamic changes in F-actin within the fertilized egg has been largely unclear. Methodology/Principal Findings We have measured changes in intracellular Ca2+ signals and F-actin structures during fertilization. We also report the unexpected observation that the conventional antagonist of the InsP3 receptor, heparin, hyperpolymerizes the cortical actin cytoskeleton in postmeiotic eggs. Using heparin and other pharmacological agents that either hypo- or hyperpolymerize the cortical actin, we demonstrate that nearly all aspects of the fertilization process are profoundly affected by the dynamic restructuring of the egg cortical actin cytoskeleton. Conclusions/Significance Our findings identify important roles for subplasmalemmal actin fibers in the process of sperm-egg interaction and in the subsequent events related to fertilization: the generation of Ca2+ signals, sperm penetration, cortical granule exocytosis, and the block to polyspermy. PMID:18974786

Postmating sexual conflict and female control over fertilization during gamete interaction.

PubMed

Firman, Renée C

2018-06-01

Males and females rarely have identical evolutionary interests over reproduction, and when the fitness of both sexes is dependent upon paternity outcomes, sexual conflict over fertilization is inevitable. In internal fertilizers, the female tract is a formidable selective force on the number and integrity of sperm that reach the egg. Selection on sperm quality is intensified when females mate multiply and rival males are forced to compete for fertilizations. While male adaptations to sperm competition have been well documented (e.g., increased sperm fertilizing capacity), much less attention has been given to the evolutionary consequences of postmating sexual conflict for egg form and function. Specifically, increased sperm competitiveness can be detrimental by giving rise to an elevation in reproductive failure resulting from polyspermy. Spanning literature on both internal and external fertilizers, in this review I discuss how females respond to sperm competition via fertilization barriers that mediate sperm entry. These findings, which align directly with sexual conflict theory, indicate that females have greater control over fertilization than has previously been appreciated. I then consider the implications of gametic sexual conflict in relation to the development of reproductive isolation and speculate on potential mechanisms accounting for "egg defensiveness." Finally, I discuss the functional significance of egg defensiveness for both the sexes, and sperm selection for females. © 2018 New York Academy of Sciences.

ELECTRIC IMPEDANCE OF THE FROG EGG

PubMed Central

Cole, Kenneth S.; Guttman, Rita M.

1942-01-01

Electrical impedance measurements were made upon unfertilized and fertilized eggs of the leopard frog, Rana pipiens, over a frequency range of 0.05 to 10 kc. Average values of 170 ohm cm.2 were obtained for the plasma membrane resistance of the egg, 2.0 µf/cm.2 for the plasma membrane capacity, 86° for the phase angle of the membrane, and 570 ohm cm. for the specific resistance of the interior. These values did not change upon fertilization. No spontaneous rhythmical impedance changes such as have been found by Hubbard and Rothschild in the trout egg were found in frog eggs. PMID:19873312

Novel genetic markers of the carbonic anhydrase II gene associated with egg production and reproduction traits in Tsaiya ducks.

PubMed

Chang, M-T; Cheng, Y-S; Huang, M-C

2013-02-01

In our previous cDNA microarray study, we found that the carbonic anhydrase II (CA2) gene is one of the differentially expressed transcripts in the duck isthmus epithelium during egg formation period. The aim of this study was to identify the single-nucleotide polymorphisms (SNPs) in the CA2 gene of Tsaiya ducks. The relationship of SNP genotype with egg production and reproduction traits was also investigated. A total of 317 ducks from two lines, a control line with no selection and a selected line, were employed for testing. Three SNPs (C37T, A62G and A65G) in the 3'-untranslated region of the CA2 gene were found. SNP-trait association analysis showed that SNP C37T and A62G were associated with duck egg weight besides fertility. The ducks with the CT and AG genotypes had a 1.46 and 1.62 g/egg lower egg weight as compared with ducks with the CC and AA genotypes, respectively (p < 0.05). But the ducks with CT and AG genotypes had 5.20% and 4.22% higher fertility than those with CC and AA genotypes, respectively (p < 0.05). Diplotype constructed on these three SNPs was associated with duck fertility, and the diplotype H1H4 was dominant for duck fertility. These findings might provide the basis for balanced selection and may be used in marker-assisted selection to improve egg weight and fertility simultaneously in the Tsaiya ducks. © 2012 Blackwell Verlag GmbH.

Artificial fertilization by intracytoplasmic sperm injection in a teleost fish, the medaka (Oryzias latipes).

PubMed

Otani, Satoshi; Iwai, Toshiharu; Nakahata, Shingo; Sakai, Chiharu; Yamashita, Masakane

2009-01-01

Intracytoplasmic sperm injection (ICSI) is a technique that has been successfully used for assisting reproduction in mammals. However, this method is still not reliable in nonmammalian species, including teleosts. We succeeded in producing medaka individuals by ICSI with a rate of 13.4% (28 hatched embryos out of 209 eggs fertilized by ICSI), the best value reported so far in teleosts, including zebrafish and Nile tilapia. Although the technique was based on that developed for mammalian eggs, some critical modifications were made to adjust it to the medaka egg, which has a thick and hard envelope (the chorion) and a single sperm entry site (the micropyle). Medaka ICSI was performed by injecting a demembranated spermatozoon into an egg cytoplasm through the micropyle 10-15 sec after egg activation induced by a piezo-actuated vibration, the site and timing of sperm penetration being consistent with those in normal fertilization in medaka. To increase the efficiency of ICSI in medaka, we found that the fertilization by ICSI should precisely mimic the fertilization by insemination with intact sperm, both spatially and temporally. The success rate of ICSI was highly variable in batches of eggs (ranging from 0% to 56%), suggesting that the conditions of eggs are important factors in stabilizing the production of individuals by ICSI. The success in medaka ICSI provides a basis for future research to understand the basic mechanisms in gamete biology of teleosts as well as for development of new technology that can yield valuable applications in fisheries science.

Selfish genetic elements and sexual selection: their impact on male fertility.

PubMed

Price, Tom A R; Wedell, Nina

2008-03-01

Females of many species mate with more than one male (polyandry), yet the adaptive significance of polyandry is poorly understood. One hypothesis to explain the widespread occurrence of multiple mating is that it may allow females to utilize post-copulatory mechanisms to reduce the risk of fertilizing their eggs with sperm from incompatible males. Selfish genetic elements (SGEs) are ubiquitous in eukaryotes, frequent sources of reproductive incompatibilities, and associated with fitness costs. However, their impact on sexual selection is largely unexplored. In this review we examine the link between SGEs, male fertility and sperm competitive ability. We show there is widespread evidence that SGEs are associated with reduced fertility in both animals and plants, and present some recent data showing that males carrying SGEs have reduced paternity in sperm competition. We also discuss possible reasons why male gametes are particularly vulnerable to the selfish actions of SGEs. The widespread reduction in male fertility caused by SGEs implies polyandry may be a successful female strategy to bias paternity against SGE-carrying males.

Selfish genetic elements and sexual selection: their impact on male fertility.

PubMed

Price, Tom A R; Wedell, Nina

2008-09-01

Females of many species mate with more than one male (polyandry), yet the adaptive significance of polyandry is poorly understood. One hypothesis to explain the widespread occurrence of multiple mating is that it may allow females to utilize post-copulatory mechanisms to reduce the risk of fertilizing their eggs with sperm from incompatible males. Selfish genetic elements (SGEs) are ubiquitous in eukaryotes, frequent sources of reproductive incompatibilities, and associated with fitness costs. However, their impact on sexual selection is largely unexplored. In this review we examine the link between SGEs, male fertility and sperm competitive ability. We show there is widespread evidence that SGEs are associated with reduced fertility in both animals and plants, and present some recent data showing that males carrying SGEs have reduced paternity in sperm competition. We also discuss possible reasons why male gametes are particularly vulnerable to the selfish actions of SGEs. The widespread reduction in male fertility caused by SGEs implies polyandry may be a successful female strategy to bias paternity against SGE-carrying males.

JPRS Report, Science & Technology, Japan, 1989 ERATO Symposia.

DTIC Science & Technology

1990-03-20

urchin eggs in fertilization. In fertilization of sea urchin eggs with seminal fluid, ovoperoxidase is secreted from the eggs causing a hardening of the...amphibians, chickens, sea urchins and other species. Simultaneously, molecular biologists have been trying to understand living organisms at the molecular...Cypridina luciferin analogues and luminol). Our group is also continuing the biochemical study of the mechanism of biophoton emission from Japanese sea

Proteome changes in rainbow trout (Oncorhynchus mykiss) fertilized eggs as an effect of triploidization heat-shock treatment.

PubMed

Babaheydari, Samad Bahrami; Keyvanshokooh, Saeed; Dorafshan, Salar; Johari, Seyed Ali

2016-03-01

The aim of the present study was to explore proteome changes in rainbow trout (Oncorhynchus mykiss) fertilized eggs as an effect of triploidization heat-shock treatment. Eggs and milt were taken from eight females and six males. The gametes were pooled to minimize the individual differences. After insemination, the eggs were incubated at 10°C for 10min. Half of the fertilized eggs were then subjected to heat shock for 10min submerged in a 28°C water bath to induce triploidy. The remainder were incubated normally and used as diploid controls. Three batches of eggs were randomly selected from each group and were incubated at 10-11°C under the same environmental conditions in hatchery troughs until the fry stage. Triplicate samples of 30 eggs (10 eggs per trough) from each group were randomly selected 1.5h post-fertilization for proteome extraction. Egg proteins were analyzed using two-dimensional electrophoresis (2-DE) and MALDI-TOF/TOF mass spectrometry. Based on the results from the statistical analyses, 15 protein spots were found to decrease significantly in abundance in heat-shock treated group and were selected for identification. Out of 15 protein spots showing altered abundance, 14 spots were successfully identified. All of the egg proteins identified in our study were related to vitellogenin (vtg). Decreased abundance of vitellogenin in heat-shock treated eggs in our study may either be explained by (i) higher utilization of vtg as an effect of increased cell size in triploids or (ii) changed metabolism in response to heat-shock stress and (iii) diffusion of vtg through chorion due to incidence of egg shell damage. Decreased abundance of vitellogenin in heat-shock treated eggs was associated with reduced early survival rates and lowered growth performance of triploid fish. Copyright © 2016 Elsevier B.V. All rights reserved.

The efficiency of a donor-recipient program using infertile donors' egg cryo-banking: a Brazilian reality.

PubMed

Figueira, Rita de Cássia Sávio; Setti, Amanda S; Braga, Daniela P A F; Iaconelli, Assumpto; Borges, Edson

2014-08-01

To determine whether Brazilian egg donation treatment outcomes with oocytes donated from infertile couples are equivalent to those obtained worldwide with oocytes donated from fertile egg-donors. In this descriptive study, egg-donation cycles from 259 women, performed from January 2009 to July 2013, were evaluated. Oocytes were obtained from patients undergoing ICSI who decided to donate their surplus oocytes. We described the survival, fertilization, blastocyst, implantation and pregnancy rates obtained in our infertile donor-recipient program. In addition, we described the results obtained in previous published studies. In our egg-donation program we obtained a fertilization rate of 72.9 %, a blastocyst formation rate of 53.2 %, an implantation rate of 31.1 % and the estimated clinical pregnancy rate per warmed oocyte was 5.4 %. The analyzed studies, performed between 2008 and 2013, included varying numbers of egg-donors (range: 20-600), warmed oocytes (range: 123-3826) and survival rates (range: 85.6-92.5 %). Fertilization rates ranged from 74.2 to 87.0 %, blastocyst formation rate ranged from 41.3 % to 68.0 %, implantation rates ranged from 24.7 % to 55.3 % and the clinical pregnancy rate per warmed oocyte ranged from 3.9 % to 9.8 %. New and reassuring information derived from our egg-donation program demonstrates outcomes similar to those reported for other egg donation programs.

Albendazole treatment in laying hens: Egg residues and its effects on fertility and hatchability.

PubMed

Moreno, Laura; Bistoletti, Mariana; Fernández, Hector; Cantón, Lucila; Ceballos, Laura; Cantón, Candela; Lanusse, Carlos; Álvarez, Luis I

2018-06-12

This work characterized the egg residual concentrations of albendazole (ABZ) and its sulphoxide (ABZSO) and sulphone (ABZSO 2 ) metabolites and evaluated their effect on egg fertility and hatchability after ABZ treatments to laying hens. Seventy hens were allocated in groups: Group-1 was the control without treatment; Group-2 received a single ABZ oral dose (10 mg/kg); Group-3, -4 and -5 were treated with ABZ in medicated feed over 7 days at 10, 40, or 80 mg kg -1  day -1 , respectively. Eggs were analyzed to determine the ABZ/metabolite level by HPLC or subjected to incubation to evaluate the fertility and hatchability. Only ABZSO and ABZSO 2 metabolites were quantified in egg after ABZ single oral administration with maximum concentrations of 0.47 ± 0.08 and 0.30 ± 0.07 μg/ml, respectively. ABZ and its metabolites were found in eggs after 7-day ABZ treatments. The egg residue exposure estimated as AUCs (areas under the concentration vs. time curve) were 100.5 (ABZ), 56.3 (ABZSO) and 141.3 μg hr g -1 (ABZSO 2 ). ABZ administration did not affect the egg fertility at any dosages. Egg hatchability was not affected by ABZ treatment at 10 mg/kg in medicated feed, but it decreased when the dose was 4-8 times higher. These results should be considered when ABZ is used for deworming laying hens. © 2018 John Wiley & Sons Ltd.

[Monitoring and SWOT analysis of Ascaris eggs pollution in soil of rural China].

PubMed

Zhu, Hui-hui; Zhou, Chang-hai; Zang, Wei; Zhang, Xue-qiang; Chen, Ying-dan

2014-06-01

To understand the status of Ascaris eggs pollution in soil at national monitoring spots of soil-transmitted nematodiasis, so as to provide the evidence for making countermeasures and evaluating the control effect. Ten households were selected from each of the 22 national monitoring spots annually according to the National Surveillance Program of Soil-Transmitted Nematodiasis (Trial), and the soil samples from vegetable gardens, toilet periphery, courtyards and kitchens were collected and examined by using the modified floatation test with saturated sodium nitrate. Fertilized or unfertilized eggs as well as live or dead fertilized eggs were discriminated and identified. In addition, a SWOT analysis of monitoring of Ascaris eggs pollution in the soil of rural China was carried out. A total of 1 090 households were monitored in 22 monitoring spots from 2006 to 2010. The total detection rate of Ascaris eggs in the soil was 30.73%, and the detection rates of fertilized, unfertilized and live fertilized eggs were 13.21%, 26.42% and 20.28%, respectively. The total detection rates of Ascaris eggs in the vegetable garden, toilet periphery, courtyard and kitchen were 16.51%, 13.49%, 14.22% and 10.73% respectively. The SWOT analysis demonstrated that the monitoring work had both advantages and disadvantages, and was faced with opportunities as well as threats. The pollution status of Ascaris eggs in the soil is still quite severe at some national monitoring spots, and the counter-measures such as implementing hazard-free treatment of stool, improving water supply and sanitation and reforming environment should be taken to protect people from being infected.

Using drift nets to capture early life stages and monitor spawning of the yangtze river chinese sturgeon (Acipenser sinensis)

USGS Publications Warehouse

Wei, Q.W.; Kynard, B.; Yang, D.G.; Chen, X.H.; Du, H.; Shen, L.; Zhang, H.

2009-01-01

A sampling system for capturing sturgeon eggs using a D-shaped bottom anchored drift net was used to capture early life stages (ELS) of Chinese sturgeon, Acipenser sinensis, and monitor annual spawning success at Yichang on the Yangtze River, 1996-2004, before and just after the Three Gorges Dam began operation. Captured were 96 875 ELS (early life stages: eggs, yolk-sac larvae = eleuthero embryos, and larvae); most were eggs and only 2477 were yolk-sac larvae. Most ELS were captured in the main river channel and inside the bend at the Yichang spawning reach. Yolk-sac larvae were captured for a maximum of 3 days after hatching began, indicating quick dispersal downstream. The back-calculated day of egg fertilization over the eight years indicated a maximum spawning window of 23 days (20 October-10 November). Spawning in all years was restricted temporally, occurred mostly at night and during one or two spawning periods, each lasting several days. The brief temporal spawning window may reduce egg predation by opportunistic predators by flooding the river bottom with millions of eggs. During 1996-2002, the percentage of fertilized eggs in an annual 20-egg sample was between 63.5 to 94.1%; however, in 2003 the percentage fertilized was only 23.8%. This sudden decline may be related to the altered environmental conditions at Yichang caused by operation of the Three Gorges Dam. Further studies are needed to monitor spawning and changes in egg fertilization in this threatened population. ?? 2009 Blackwell Verlag GmbH.

MOLECULAR ARCHITECTURE OF THE HUMAN SPERM IZUMO1 AND EGG JUNO FERTILIZATION COMPLEX

PubMed Central

Aydin, Halil; Sultana, Azmiri; Li, Sheng; Thavalingam, Annoj; Lee, Jeffrey E.

2017-01-01

Fertilization is an essential biological process in sexual reproduction and comprises a series of molecular interactions between the sperm and egg1,2. The fusion of haploid spermatozoon and oocyte is the culminating event in mammalian fertilization, enabling the creation of a new genetically distinct diploid organism3,4. The merger of two gametes is achieved through a two-step mechanism where the sperm Izumo1 on the equatorial segment of the acrosome-reacted sperm recognizes its receptor Juno, on the egg surface4–6. This is followed by the fusion of two plasma membranes. Izumo1 and Juno proteins are indispensable for fertilization as constitutive knockout of either Izumo1 or Juno result in mice that are healthy but infertile5,6. Despite their central importance in reproductive medicine, the molecular architectures and the details of their functional roles in fertilization are not known. Here, we present the crystal structures of the human Izumo1 and Juno in unbound and bound conformations. The human Izumo1 structure exhibits a distinct boomerang shape and provides the first structural insights into the Izumo family of proteins7. Human Izumo1 forms a high-affinity complex with Juno and undergoes a major conformational change within its N-terminal domain upon binding to the egg-surface receptor. Our results provide new insights into the molecular basis of sperm-egg recognition, cross-species fertilization, and barrier to polyspermy, thus promising benefits for the rational development of novel non-hormonal contraceptives and fertility treatments for humans and other species of mammals. PMID:27309818

Experimental parameterisation of principal physics in buoyancy variations of marine teleost eggs.

PubMed

Jung, Kyung-Mi; Folkvord, Arild; Kjesbu, Olav Sigurd; Sundby, Svein

2014-01-01

It is generally accepted that the high buoyancy of pelagic marine eggs is due to substantial influx of water across the cell membrane just before ovulation. Here we further develop the theoretical basis by applying laboratory observations of the various components of the fertilized egg in first-principle equations for egg specific gravity (ρ(egg)) followed by statistical validation. We selected Atlantic cod as a model animal due to the affluent amount of literature on this species, but also undertook additional dedicated experimental works. We found that specific gravity of yolk plus embryo is central in influencing ρ(egg) and thereby the buoyancy. However, our established framework documents the effect on ρ(egg) of the initial deposition of the heavy chorion material in the gonad prior to spawning. Thereafter, we describe the temporal changes in ρ(egg) during incubation: Generally, the eggs showed a slight rise in ρ(egg) from fertilization to mid-gastrulation followed by a gradual decrease until full development of main embryonic organs just before hatching. Ontogenetic changes in ρ(egg) were significantly associated with volume and mass changes of yolk plus embryo. The initial ρ(egg) at fertilization appeared significantly influenced by the chorion volume fraction which is determined by the combination of the final chorion volume of the oocyte and of the degree of swelling (hydrolyzation) prior to spawning. The outlined principles and algorithms are universal in nature and should therefore be applicable to fish eggs in general.

Experimental Parameterisation of Principal Physics in Buoyancy Variations of Marine Teleost Eggs

PubMed Central

Jung, Kyung-Mi; Folkvord, Arild; Kjesbu, Olav Sigurd; Sundby, Svein

2014-01-01

It is generally accepted that the high buoyancy of pelagic marine eggs is due to substantial influx of water across the cell membrane just before ovulation. Here we further develop the theoretical basis by applying laboratory observations of the various components of the fertilized egg in first-principle equations for egg specific gravity (ρegg) followed by statistical validation. We selected Atlantic cod as a model animal due to the affluent amount of literature on this species, but also undertook additional dedicated experimental works. We found that specific gravity of yolk plus embryo is central in influencing ρegg and thereby the buoyancy. However, our established framework documents the effect on ρegg of the initial deposition of the heavy chorion material in the gonad prior to spawning. Thereafter, we describe the temporal changes in ρegg during incubation: Generally, the eggs showed a slight rise in ρegg from fertilization to mid-gastrulation followed by a gradual decrease until full development of main embryonic organs just before hatching. Ontogenetic changes in ρegg were significantly associated with volume and mass changes of yolk plus embryo. The initial ρegg at fertilization appeared significantly influenced by the chorion volume fraction which is determined by the combination of the final chorion volume of the oocyte and of the degree of swelling (hydrolyzation) prior to spawning. The outlined principles and algorithms are universal in nature and should therefore be applicable to fish eggs in general. PMID:25122447

Cytoskeleton and gravity at work in the establishment of dorso-ventral polarity in the egg of Xenopus laevis

NASA Astrophysics Data System (ADS)

Ubbels, Geertje A.; Brom, Tim G.

The establishment of polarities during early embryogenesis is essential for normal development. Amphibian eggs are appropriate models for studies on embryonic pattern formation. The animal-vegetal axis of the axially symmetrical amphibian egg originates during oogenesis and foreshadows the main body axis of the embryo. The dorso-ventral polarity is epigenetically established before first cleavage. Recent experiments strongly suggest that in the monospermic eggs of the anuran Xenopus laevis both the cytoskeleton and gravity act in the determination of the dorso-ventral polarity. In order to test the role of gravity in this process, eggs will be fertilized under microgravity conditions during the SL-D1 flight in 1985. In a fully automatic experiment container eggs will be kept under well-defined conditions and artificially fertilized as soon as microgravity is reached; eggs and embryos at different stages will then be fixed for later examination. Back on earth the material will be analysed and we will know whether fertilization under microgravity conditions is possible. If so, the relation of the dorso-ventral axis to the former sperm entry point will be determined on the whole embryos; in addition eggs and embryos will be analysed cytologically.

Effects of PCB contamination on the reproduction of the DAB Limanda limanda L. under laboratory conditions

NASA Astrophysics Data System (ADS)

Fonds, Mark; Casal, Elizabeth; Schweizer, Dominik; Boon, Jan P.; Van der Veer, Henk W.

The effect of PCB contamination on the reproduction of female dab was studied under laboratory conditions. Females were contaminated during gonad maturation by multiple oral administration of capsules containing the technical PCB mixture Clophen A40. PCB contamination resulted in increased levels in the eggs, with concentrations of selected PCB congeners of 35 to 86 μg·g -1 lipid for PCB-exposed fish, 10 μg·g -1 lipid for eggs from fish fed with mussel meat and fish fed with shrimp. A statistically significant dose-effect relationship was found between the PCB content of the eggs and the PCB dose ingested by the fish. For eggs from the PCB-treated fish the mean fertilization rate was 61% and mean hatching 45%, compared to 67% fertilization and 59% hatching for eggs from untreated fish. Rate of development and survival of the eggs and mortality of the larvae after hatching were mainly related to incubation temperature. No statistically significant differences between untreated and PCB-treated fish could be found in egg production, egg quality, fertilization rate, hatching rate and survival of larvae.

The Effects of Ammonium Perchlorate on Reproduction and Development of Amphibians

DTIC Science & Technology

2008-01-01

Abstract: Ammonium perchlorate is a pervasive pollutant primarily from rocket fuel and fertilizers . It is know , among other things , to affect...females, their ovulated eggs collected, and in vitro fertilization conducted. Healthy ovulated eggs were selected and placed in Petri dishes...used and fertilization accomplished in vitro in the presence of perchlorate concentrations. *These tasks were not completed. Studies with Sodium

Difference Between Identical and Fraternal Twins

MedlinePlus

... chromosomes and a girl has XX chromosomes. Girl-boy twins occur when one X egg is fertilized with an X sperm, and a Y sperm fertilizes the other X egg. Sometimes health care professionals identify same-sex twins as fraternal or identical based on ultrasound ...

Egg Viability, Mating Frequency and Male Mating Ability Evolve in Populations of Drosophila melanogaster Selected for Resistance to Cold Shock

PubMed Central

Singh, Karan; Kochar, Ekta; Prasad, N. G.

2015-01-01

Background Ability to resist temperature shock is an important component of fitness of insects and other ectotherms. Increased resistance to temperature shock is known to affect life-history traits. Temperature shock is also known to affect reproductive traits such as mating ability and viability of gametes. Therefore selection for increased temperature shock resistance can affect the evolution of reproductive traits. Methods We selected replicate populations of Drosophila melanogaster for resistance to cold shock. We then investigated the evolution of reproductive behavior along with other components of fitness- larval survivorship, adult mortality, fecundity, egg viability in these populations. Results We found that larval survivorship, adult mortality and fecundity post cold shock were not significantly different between selected and control populations. However, compared to the control populations, the selected populations laid significantly higher percentage of fertile eggs (egg viability) 24 hours post cold shock. The selected populations had higher mating frequency both with and without cold shock. After being subjected to cold shock, males from the selected populations successfully mated with significantly more non-virgin females and sired significantly more progeny compared to control males. Conclusions A number of studies have reported the evolution of survivorship in response to selection for temperature shock resistance. Our results clearly indicate that adaptation to cold shock can involve changes in components of reproductive fitness. Our results have important implications for our understanding of how reproductive behavior can evolve in response to thermal stress. PMID:26065704

Fertilization success of an arctic sea urchin species, Strongylocentrotus droebachiensis (O. F. Müller, 1776) under CO2-induced ocean acidification

NASA Astrophysics Data System (ADS)

Bögner, D.; Bickmeyer, U.; Köhler, A.

2013-05-01

Sea urchins as broadcasting spawners, release their gametes into open water for fertilization, thus being particularly vulnerable to ocean acidification. In this study, we assessed the effects of different pH scenarios on fertilization success of Strongylocentrotus droebachiensis, collected at Spitsbergen, Arctic. We achieved acidification by bubbling CO2 into filtered seawater using partial pressures (pCO2) of 180, 380, 980, 1400 and 3000 μatm}. Untreated filtered seawater was used as control. We recorded fertilization rates and diagnosed morphological aberrations after post-fertilization periods of 1 h and 3 h under different exposure conditions in experiments with and without pre-incubation of the eggs prior to fertilization. In parallel, we conducted measurements of intracellular pH changes using BCECF/AM in unfertilized eggs exposed to a range of acidified seawater. We observed increasing rates of polyspermy in relation to higher seawater pCO2, which might be due to failures in the formation of the fertilization envelope. In addition, our experiments showed anomalies in fertilized eggs: incomplete lifting-off of the fertilization envelope and blebs of the hyaline layer. Other drastic malformations consisted of constriction, extrusion, vacuolization or degeneration (observed as a gradient from the cortex to the central region of the cell) of the egg cytoplasm, and irregular cell divisions until 2- to 4-cell stages. The intracellular pH (pHi) decreased significantly from 1400 μatm on. All results indicate a decreasing fertilization success at CO2 concentrations from 1400 μatm upwards. Exposure time to low pH might be a threatening factor for the cellular buffer capacity, viability, and development after fertilization.

Toxicity of nitrogenous fertilizers to eggs of snapping turtles (Chelydra serpentina) in field and laboratory exposures.

PubMed

de Solla, Shane Raymond; Martin, Pamela Anne

2007-09-01

Many reptiles oviposit in soil of agricultural landscapes. We evaluated the toxicity of two commonly used nitrogenous fertilizers, urea and ammonium nitrate, on the survivorship of exposed snapping turtle (Chelydra serpentina) eggs. Eggs were incubated in a community garden plot in which urea was applied to the soil at realistic rates of up to 200 kg/ha in 2004, and ammonium nitrate was applied at rates of up to 2,000 kg/ha in 2005. Otherwise, the eggs were unmanipulated and were subject to ambient temperature and weather conditions. Eggs were also exposed in the laboratory in covered bins so as to minimize loss of nitrogenous compounds through volatilization or leaching from the soil. Neither urea nor ammonium nitrate had any impact on hatching success or development when exposed in the garden plot, despite overt toxicity of ammonium nitrate to endogenous plants. Both laboratory exposures resulted in reduced hatching success, lower body mass at hatching, and reduced posthatching survival compared to controls. The lack of toxicity of these fertilizers in the field was probably due to leaching in the soil and through atmospheric loss. In general, we conclude that nitrogenous fertilizers probably have little direct impacts on turtle eggs deposited in agricultural landscapes.

The ART of mating: alternative reproductive tactics and mating success in a nest-guarding fish.

PubMed

Mascolino, S; Benvenuto, C; Gubili, C; Sacchi, C; Boufana, B; Mariani, S

2016-12-01

Behavioural observations in the field of male Mediterranean damselfish Chromis chromis were combined with molecular analyses, using bi-parentally and maternally inherited markers, to investigate reproductive success patterns of alternative reproductive tactics (ARTs) in terms of number of eggs sired and number of females contributing to each nest. Cuckoldry was observed in every nest sampled, with at least two and up to seven sneaker males per nest. The nesting male, however, always significantly fertilized the greater number of eggs (on average 49%) in each clutch, whereas each sneaker fertilized around 7% of the clutch. The average number of females whose eggs were fertilized by nesting males was 6·76 (range 2-13), while each sneaker on average fertilized the eggs of 1·74 (range 1-8) females. Using this sibship reconstruction, some of the factors involved in the regulation of the dynamic equilibrium of reproductive success were investigated between the two ARTs shown by C. chromis males. Results show that the sneakers' reproductive success was positively linked to egg clutch size; the density of individuals in the nesting area negatively affected the size of egg clutches; the rate of defence behaviours performed by nesting males negatively influenced the number of females contributing to each nest. © 2016 The Fisheries Society of the British Isles.

Activation of the proteasomes of sand dollar eggs at fertilization depends on the intracellular pH rise.

PubMed

Chiba, K; Alderton, J M; Hoshi, M; Steinhardt, R A

1999-05-01

The mechanism of the activation of intracellular proteasomes at fertilization was measured in living sand dollar eggs using the membrane-impermeant fluorogenic substrate, succinyl-Phe-Leu-Arg-coumarylamido-4-methanesulfonic acid. When the substrate was microinjected into unfertilized eggs, the initial velocity of hydrolysis of the substrate (V0) was low. V0 measured 5 to 10 min after fertilization was five to nine times the prefertilization level and remained high throughout the first cell cycle. Hydrolysis of the substrate was inhibited by clasto-lactacystin beta-lactone, a specific inhibitor of the proteasome. There has been in vitro evidence that calcium may be involved in regulation of proteasome activity to either inhibit the increase in peptidase activity associated with PA 28 binding to the 20S proteasome or stimulate activity of the PA 700-proteasome complex. Since both intracellular free Ca2+ concentration ([Ca2+]i) and intracellular pH (pHi) increase after fertilization, hydrolysis of the proteasome substrate was measured under conditions in which [Ca2+]i and pHi were varied independently during activation. When the pHi of unfertilized eggs was elevated by exposure to 15 mM ammonium chloride in pH 9 seawater, V0 increased to a level comparable to that measured after fertilization. In contrast, [Ca2+]i elevation without pHi change, induced by calcium ionophore in sodium-free seawater, had no effect on V0 in the unfertilized egg. Moreover, when unfertilized eggs were microinjected with buffers modulating pHi, V0 increased in a pH-dependent manner. These results indicate that the pHi rise at fertilization is the necessary prerequisite for activation of the proteasome, an essential component in the regulation of the cell cycle. Copyright 1999 Academic Press.

Effect of parental exposure to trenbolone and the brominated flame retardant BDE-47 on fertility in rainbow trout (Oncorhynchus mykiss)

PubMed Central

Schultz, Irv; Brown, Kim H.; Nagler, James J.

2008-01-01

We exposed sexually maturing male rainbow trout (Oncorhynchus mykiss) to BDE-47 (a polybrominated diphenyl ether) and female rainbow trout to trenbolone (an anabolic steroid). Male trout were orally exposed for 17 days to 55 μg/kg/day BDE-47 and female trout continuously exposed for 60–77 days to a measured trenbolone water concentration of 35 ng/L. After the exposure, eggs and semen were collected and in vitro fertilization trials performed using a sperm:egg ratio of 300,000:1. In the BDE-47 study, eggs from control females were fertilized with semen from exposed males, while in the trenbolone study, eggs from exposed females were fertilized with semen from control males. All treatments were evaluated at two–three early developmental time-points representing first cleavage (0.5 day), embryonic keel (9 days), and eyed stages (19 days), respectively. The results indicated that BDE-47 exposure did not alter fertility as embryonic survival was similar between control and exposed groups. Trenbolone exposure also did not alter embryo survival. However, in the embryos fertilized with eggs from trenbolone exposed females, a noticeable delay in developmental progress was observed. On day 19 when eye development is normally complete, the majority of the embryos either lacked eyes or displayed under-developed eyes, in contrast to control embryos. This finding suggests steroidal androgen exposure in sexually maturing female rainbow trout can impact developmental timing of F1 offspring. PMID:18397801

Effect of parental exposure to trenbolone and the brominated flame retardant BDE-47 on fertility in rainbow trout (Oncorhynchus mykiss).

PubMed

Schultz, Irv; Brown, Kim H; Nagler, James J

2008-07-01

We exposed sexually maturing male rainbow trout (Oncorhynchus mykiss) to BDE-47 (a polybrominated diphenyl ether) and female rainbow trout to trenbolone (an anabolic steroid). Male trout were orally exposed for 17 days to 55 microg/kg/day BDE-47 and female trout continuously exposed for 60-77 days to a measured trenbolone water concentration of 35 ng/L. After the exposure, eggs and semen were collected and in vitro fertilization trials performed using a sperm:egg ratio of 300,000:1. In the BDE-47 study, eggs from control females were fertilized with semen from exposed males, while in the trenbolone study, eggs from exposed females were fertilized with semen from control males. All treatments were evaluated at two-three early developmental time-points representing first cleavage (0.5 day), embryonic keel (9 days), and eyed stages (19 days), respectively. The results indicated that BDE-47 exposure did not alter fertility as embryonic survival was similar between control and exposed groups. Trenbolone exposure also did not alter embryo survival. However, in the embryos fertilized with eggs from trenbolone exposed females, a noticeable delay in developmental progress was observed. On day 19 when eye development is normally complete, the majority of the embryos either lacked eyes or displayed under-developed eyes, in contrast to control embryos. This finding suggests steroidal androgen exposure in sexually maturing female rainbow trout can impact developmental timing of F1 offspring.

Ocean acidification hampers sperm-egg collisions, gamete fusion, and generation of Ca2+ oscillations of a broadcast spawning bivalve, Tegillarca granosa.

PubMed

Shi, Wei; Han, Yu; Guo, Cheng; Zhao, Xinguo; Liu, Saixi; Su, Wenhao; Wang, Yichen; Zha, Shanjie; Chai, Xueliang; Liu, Guangxu

2017-09-01

Although the effect of ocean acidification on fertilization success of marine organisms is increasingly well documented, the underlying mechanisms are not completely understood. The fertilization success of broadcast spawning invertebrates depends on successful sperm-egg collisions, gamete fusion, and standard generation of Ca 2+ oscillations. Therefore, the realistic effects of future ocean pCO 2 levels on these specific aspects of fertilization of Tegillarca granosa were investigated in the present study through sperm velocity trials, fertilization kinetics model analysis, and intracellular Ca 2+ assays, respectively. Results obtained indicated that ocean acidification significantly reduced the fertilization success of T. granosa, which could be accountable by (i) decreased sperm velocity hence reducing the probability for sperm-egg collisions; (ii) lowered probability of gamete fusion for each gamete collision event; and (iii) disrupted intracellular Ca 2+ oscillations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Law No. 711 on fertilization outside the human body, 14 June 1988.

PubMed

1988-01-01

This Swedish Law reads as follows: "Section 1: this Law shall apply to the fertilization of a woman's egg outside her body, for the purpose of producing a child. Section 2: an egg which has been fertilized outside the body of a woman may not be introduced into her body unless: 1) the woman is married or living in a state of cohabitation; 2) the husband or cohabitant gives his written consent; and 3) the egg is the woman's own and has been fertilized with the sperm of her husband or cohabitant. Section 3: unless the authorization of the National Board of Health and Welfare is obtained, fertilization outside the human body may only be carried out in a general hospital. Section 4: persons committing a breach of Section 2 or 3 habitually or for gain shall be liable to a fine or to a prison sentence not exceeding six months." full text

Picking the right tool for the job – phosphor-proteomics of egg activation

PubMed Central

Wessel, Gary M.

2016-01-01

Eggs are the rarest cell in the human body, yet their study is essential for the fields of fertility, reproduction, and fetal health. Guo et al use a “surrogate” animal to discover the phophoproteomic pathways involved in egg activation. With datasets of several thousand phophosites on 2500 different proteins, these investigators have defined new pathways, connections to pathways, and priorities in searches for how eggs are activated at fertilization. These results in a sea urchin are now transposable to mammals for testing on a per candidate strategy. PMID:26573262

Maternal corticosterone reduces egg fertility and hatchability and increases the numbers of early dead embryos in eggs laid by quail hens selected for exaggerated adrenocortical stress responsiveness.

PubMed

Schmidt, J B; Satterlee, D G; Treese, S M

2009-07-01

Quail hens selected for exaggerated (HS, high stress) rather than reduced (LS, low stress) plasma corticosterone (B) response to brief restraint deposit more B into their egg yolks than do LS hens. Female progeny of HS hens implanted with B also show reduced egg production when compared with female offspring of LS- and HS-control and LS-B-implanted hens. Herein, LS and HS hens were implanted (s.c.) with empty (controls, CON) or B-filled silastic tubes to assess the interactive influences of maternal B-treatment with quail stress line on egg fertility (FERT), total egg hatchability (TOTHATCH) and fertile egg hatchability, and the percentages of embryonic mortality (early dead, ED; late dead) and pipped eggs. Mean FERT was dramatically reduced in eggs of HS compared with LS hens and B-implanted compared with CON-treated hens (P < 0.0001, both cases). Line x implant treatment FERT outcomes partitioned (P < 0.05) as follows: LS-B = LS-CON > HS-CON > HS-B. In addition, TOTHATCH was also affected by line (LS > HS; P < 0.0001) and implant treatment (CON > B-implant; P < 0.0002) and line x implant treatment TOTHATCH means differed (P < 0.05) as follows: LS-CON = LS-B = HS-CON > HS-B. Fertile egg hatchability was reduced (P < 0.05) in HS-B-treated hen eggs when compared with LS-B and HS-CON hen eggs and more (P < 0.05) ED embryos were found in eggs laid by HS-B-implanted hens than in any other treatment group. Late dead and pipped egg percentages were unaffected by any treatment. The findings are important to avian geneticists because they further emphasize the benefits that selection for reduced adrenocortical responsiveness has on hen reproductive performance. The maternal B findings also warn poultry and hatchery managers that unless hen stress during egg formation is avoided, negative consequences in FERT, TOTHATCH, and ED can result, particularly in hens genetically predisposed toward exaggerated adrenal stress responsiveness.

The discrimination of fish egg quality and viability by using Raman spectroscopy

NASA Astrophysics Data System (ADS)

Ishigaki, Mika; Sato, Hidetoshi

2014-03-01

Sexual reproductive body can be produced from a fertilized ovum. Once the ovum is fertilized with sperm, it runs through the cell division, differentiates to all kinds of cells, and goes to make a complete body. However, not all of them are viable and some of them stop to ontogenesis showing the developmental abnormality. In order to discriminate the egg quality, we apply Raman spectroscopy for fish egg. After the measurement, these Raman data are checked up with the information about the eggs can survive or not, and we examine what factors are important in egg components to distinguish between "good quality" and "not good quality". We present the results of assessment of egg quality, and investigate whether Raman spectroscopy can be used to a discriminate of egg quality.

Process of egg formation in the female body cavity and fertilization in male eggs of Phytoseiulus persimilis (Acari: Phytoseiidae).

PubMed

Toyoshima, S; Nakamura, M; Nagahama, Y; Amano, H

2000-01-01

The process of egg formation in the body cavity of a phytoseiid mite, Phytoseiulus persimilis, was observed to examine fertilization of male eggs. After insemination, one of the ova at the periphery of the ovary began to expand, taking up yolk. Two pronuclei appeared in the expanded egg, located dorsally in the ovary, and yolk granules were formed gradually. After the egg became filled with yolk granules the two pronuclei fused. The egg moved via the narrow entrance at the ventral region into the oviduct, where the eggshell was formed. When the eggshell was complete, and while embryogenesis proceeded, the egg was deposited. In the meantime some ova began to expand sequentially and two joining pronuclei appeared in expanding eggs. The joining pronuclei in the first egg proved male diploidy. This is additional evidence of pseudo-arrhenotoky in this phytoseiid mite species, since the first eggs developed into males.

The effects of microgravity on gametogenesis, fertilization, and early embryogenesis

NASA Astrophysics Data System (ADS)

Tan, X.

Gametogenesis fertilization and early embryogenesis are crucial periods for normal development afterwards In past three decades many experiments have been conducted in space and in simulated weightlessness induced by clinostats to elucidate the issue Different animal species including Drosophila wasp shrimp fish amphibian mouse rats etc have been used for the study Oogenesis and spermatogenesis are affected by microgravity in different ways Some researches found that microgravity condition perturbed the process of oogenesis in many species A significant increased frequency of chromosomal non-disjunction was found in Drosophila females resulting the loss of chromosomes during meiosis and inhibition of cell division Studies on wasp showed a decreased hatchability and accumulation of unhatched eggs when the insects were exposed to spaceflight at different stages of oogenesis For experiments conducted on vertebrate animal models the results are somehow different however Microgravity has no significant effect for fish Medaka etc amphibian South African clawed toad Xenopus laevis or mammals mouse Spermatogenesis on the other hand is more significantly affected by microgravity condition Some researches indicated sperm are sensitive to changes in gravitational force and this sensitivity affects the ability of sperm to fertilize eggs Sperm swim with higher velocity in microgravity which is coupled with altered protein phosphorylation level in sperm under microgravity condition Microgravity also induced activation of the

[PKA-regulated phosphorylation status of S149 and S321 sites of CDC25B inhibits mitosis of fertilized mouse eggs].

PubMed

Xiao, Jian-Ying; Liu, Chao; Sun, Xiao-Han; Yu, Bing-Zhi

2012-02-25

To further test whether protein kinase A (PKA) can affect the mitotic cell cycle, one-cell stage mouse embryos at S phase (22 h after hCG injection) were incubated in M16 medium containing various concentrations of H-89, a PKA inhibitor. With increasing concentrations of H-89 (0-50 μmol/L), the G(2) phase of eggs was decreased and the cleavage rate was accelerated. A concentration of 40 μmol/L H-89 led to all of the mouse eggs entering the M phase of mitosis. Furthermore, to study the role of PKA in regulating the phosphorylation status of S149 and S321 sites of cell division cycle 25B (CDC25B) on one-cell stage fertilized mouse eggs, pBSK-CDC25B-WT, pBSK-CDC25B-S149A, pBSK-CDC25B-S321A and pBSK-CDC25B-S149A/S321A were transcribed into mRNAs in vitro, then mRNAs were microinjected into S phase of mouse fertilized eggs and cultured in M16 medium pretreated with H-89. Then, the cleavage of fertilized eggs, maturation promoting factor (MPF) activity and phosphorylation status of CDC2-Tyr15 were observed. In the presence of 40 μmol/L H-89, the cleavage rate of fertilized eggs in CDC25B-S/A-mRNAs and CDC25B-WT-mRNA injected groups was significantly higher than that in the control groups, and the peak of MPF activity appeared in the CDC25B-S/A-mRNAs and CDC25B-WT-mRNA injected groups earlier than that in the control groups. CDC2-Tyr15 phosphorylation state was consistent with MPF activity. In conclusion, the present study suggests that PKA regulates the early development of mouse embryos by phosphorylation of S149 and S321 of CDC25B, which plays an important role in the regulation of G(2)/M transition in the mitotic cell cycle of fertilized mouse eggs.

First observations of fertilized eggs and preleptocephalus larvae of Rhinomuraena quaesita in the Vienna Zoo.

PubMed

Preininger, D; Halbauer, R; Bartsch, V; Weissenbacher, A

2015-01-01

For the first time worldwide, fertilized eggs of ribbon eels (Rhinomuraena quaesita) hatched into feeding preleptocephali and could be kept alive for a period of seven days in the Vienna Zoo. The study reports on husbandry, behavioral observations and dimensions of eggs and preleptocephalus larvae. Furthermore, body color variations of ribbon eels in captivity do not reflect its sex or sexual maturity. © 2014 Wiley Periodicals, Inc.

Farmers' breeding practices and traits of economic importance for indigenous chicken in RWANDA.

PubMed

Mahoro, J; Muasya, T K; Mbuza, F; Mbuthia, J; Kahi, A K

2018-01-01

Data on breeding practices and traits of economic importance for the indigenous chicken (IC) were collected through personal interviews using structured questionnaires and direct observations of chicken management practices. The study was conducted from November 2015 to January 2016 in Rwamagana, Rulindo, Ruhango, Kicukiro and Muhanga districts of Rwanda. Data were collected and analysed through computation of indices, which represented a weighted average of all rankings of a specific trait. Spearman's non-parametric rank correlation was calculated for ranking of traits of economic importance to indicate the directional effects. The results on chicken ecotypes and their attributes showed that prolificacy, mature weight, disease tolerance, egg number and heat tolerance were highly preferred. The dwarf ecotype was most abundantly reared (38.84%) and considered to be significantly smaller and to have poorer growth rate, but to have better prolificacy than other indigenous chicken ecotypes. Selection of breeding cock and hen was based on disease tolerance, body weight at sexual maturity, body size and growth rate. In addition, for hen, mothering ability and egg fertility (Fer) were considered. Indices for the traits perceived by farmers as of primary economic importance were egg yield (0.093), disease tolerance (0.091), high growth rate (0.089), prolificacy (0.088), high body weight (0.087) and egg fertility (0.083). The most important traits considered by the marketers were body weight (BW), disease tolerance (Dtol), plumage colour (Pcol), egg yolk colour (EYC), meat quality (MQ), growth rate (GR) and egg yield (EY) whereas for consumers, meat quality, egg yolk colour, egg yield, body weight and growth rate were considered. Among traits perceived as important by farmers, a positive and significant correlation was found between BW and GR and Fer. Correlation was moderate for BW and prolificacy, drought tolerance (Drtol), Dtol and EYC. BW was negatively correlated with temperament (Temp), heat tolerance, Pcol and egg shell colour (ESC). Regarding marketers and consumers' preference rank correlation, positive and significant correlation was between BW and GR and MQ. As such, appropriate ecotypes (indigenous chicken) which have these characteristics need to be identified and utilised more based on their performance and adaption to the environment conditions to ensure efficient IC production.

DEVELOPMENTAL PATTERN AND ADAPTATIONS FOR REPRODUCTION IN NUCELLA CRASSILABRUM AND OTHER MURICACEAN GASTROPODS.

PubMed

Gallardo, C S

1979-12-01

1. Eggs of Nucella crassilabrum range from 204 to 293 µm in diameter (mean = 240 µm). Only 6.6 to 7.9% are fertile; the remaining are ingested as nurse eggs. 2. Embryos metamorphose before hatching. Pre-hatching time ranges from 55 to 80 days according to seasonal temperature fluctuations. 3. Hatching size varies from 0.82 to 1.3 mm, depending on number of nurse-eggs ingested per embryo (from 3 to 20). Number of fertile embryos per capsule (10 to 122) depends on capsule size. 4. Hatching type and hatching size shown by N. crassilabrum agree with those of other muricaceans living in similar habitat conditions. 5. Pre-hatching time and hatching size data of various muricaceans are analyzed to determine to what extent they influence embryonic mode of nutrition, namely the presence of nurse-eggs or alternatively large and fertile self-sufficient eggs. Provision of nurse-eggs for embryos is of common occurrence among intertidal muricaceans and this mode of nutrition seems to have been favored in such habitats to reduce developmental time. Providing the yolk as nurse-eggs seems also to contribute to a larger hatching size, as suggested by some subtidal muricaceans with such embryo support patterns.

Alternative complement activity in the egg cytosol of amphioxus Branchiostoma belcheri: evidence for the defense role of maternal complement components.

PubMed

Liang, Yujun; Zhang, Shicui; Wang, Zhiping

2009-01-01

The eggs in most invertebrates are fertilized externally, and therefore their resulting embryos are exposed to an environment full of microbes, many of which are pathogens capable of killing other organisms. How the developing embryos of invertebrates defend themselves against pathogenic attacks is an intriguing question to biologists, and remains largely unknown. Here we clearly demonstrated that the egg cytosol prepared from the newly fertilized eggs of amphioxus Branchiostoma belcheri, an invertebrate chordate, was able to inhibit the growth of both the Gram-negative bacterium Vibrio anguillarum and the Gram-positive bacterium Staphylococcus aureus. All findings point to that it is the complement system operating via the alternative pathway that is attributable to the bacteriostatic activity. This appears to be the first report providing the evidence for the functional role of the maternal complement components in the eggs of invertebrate species, paving the way for the study of maternal immunity in other invertebrate organisms whose eggs are fertilized in vitro. It also supports the notion that the early developing embryos share some defense mechanisms common with the adult species.

Calcium pathway machinery at fertilization in echinoderms

PubMed Central

Ramos, Isabela; Wessel, Gary M.

2016-01-01

Calcium signaling in cells directs diverse physiological processes. The calcium waves triggered by fertilization is a highly conserved calcium signaling event essential for egg activation, and has been documented in every egg tested. This activity is one of the few highly conserved events of egg activation through the course of evolution. Echinoderm eggs, as well as many other cell types, have three main intracellular Ca2+ mobilizing messengers – IP3, cADPR and NAADP. Both cADPR and NAADP were identified as Ca2+ mobilizing messengers using the sea urchin egg homogenate, and this experimental system, along with the intact urchin and starfish oocyte/egg, continues to be a vital tool for investigating the mechanism of action of calcium signals. While many of the major regulatory steps of the IP3 pathway are well resolved, both cADPR and NAADP remain understudied in terms of our understanding of the fundamental process of egg activation at fertilization. Recently, NAADP has been shown to trigger Ca2+ release from acidic vesicles, separately from the ER, and a new class of calcium channels, the two-pore channels (TPCs), was identified as the likely targets for this messenger. Moreover, it was found that both cADPR and NAADP can be synthesized by the same family of enzymes, the ADP-rybosyl cyclases (ARCs). In this context of increasing amount of information, the potential coupling and functional roles of different messengers, intracellular stores and channels in the formation of the fertilization calcium wave in echinoderms will be critically evaluated. PMID:23218671

In vitro embryo production in camel (Camelus dromedarius) from in vitro matured oocytes fertilized with epididymal spermatozoa stored at 4 degrees C.

PubMed

Wani, N A

2009-03-01

Experiments were conducted to study the effect of storing epididymal spermatozoa, in tris-tes- and tris-lactose egg yolk extenders, on their fertilizing ability and subsequent in vitro embryo development. Ovaries and testes were collected from a local slaughterhouse in normal saline solution (NSS) at 37 degrees C and on ice (0-1 degrees C), respectively. Cumulus oocyte complexes (COCs) aspirated from the follicles were randomly distributed to 4-well culture plates (20-25COCs/well) containing 500 microL of maturation medium and cultured at 38.5 degrees C in an atmosphere of 5% CO(2) in air for 36 h. Spermatozoa were collected from the cauda epididymides in syringes containing 2-3 mL of either tris-tes- or tris-lactose egg yolk extender. They were cooled down slowly and stored at refrigeration (4 degrees C) temperature. The spermatozoa were evaluated for motility and used for IVF of IVM oocytes on the day of collection and after 2, 4, 6 and 8 days of storage. On the day of IVF, spermatozoa were prepared by the swim up technique and both spermatozoa and oocytes were co-incubated at 38.5 degrees C in a humidified atmosphere of 5% CO(2) in air for 15-16 h. Presumptive zygotes were either fixed and stained with Hoechst 33342 for evaluation of fertilization or were cultured in 500 microL of the culture medium at 38.5 degrees C in an atmosphere of 5% CO(2), 5% O(2) and 90% N(2) in air. There was no significant difference (P>0.05) in the proportion of oocytes fertilized with spermatozoa stored in either of the two extenders for up to 8 days. The proportion of oocytes that cleaved (43-60%) and those that developed to blastocysts (14-21%) did not show any difference (P>0.05) either, when spermatozoa from different days of storage were used. First cleavage was observed as early as 16 h after IVF, early blastocysts had developed by day 4, expanded blastocysts after day 5 and hatching of blastocysts started after day 6 of culture. It may be concluded that dromedary epididymal spermatozoa survive in storage for at least 8 days in tris-lactose- and tris-tes egg yolk diluents at 4 degrees C. These spermatozoa maintain fertilizing ability and may be suitable for use in IVF and other assisted reproductive procedures.

Comparison of Egg Envelope Thickness in Teleosts and its Relationship to the Sites of ZP Protein Synthesis.

PubMed

Sano, Kaori; Kawaguchi, Mari; Katano, Keita; Tomita, Kenji; Inokuchi, Mayu; Nagasawa, Tatsuki; Hiroi, Junya; Kaneko, Toyoji; Kitagawa, Takashi; Fujimoto, Takafumi; Arai, Katsutoshi; Tanaka, Masaru; Yasumasu, Shigeki

2017-05-01

Teleost egg envelope generally consists of a thin outer layer and a thick inner layer. The inner layer of the Pacific herring egg envelope is further divided into distinct inner layers I and II. In our previous study, we cloned four zona pellucida (ZP) proteins (HgZPBa, HgZPBb, HgZPCa, and HgZPCb) from Pacific herring, two of which (HgZPBa and HgZPCa) were synthesized in the liver and two (HgZPBb and HgZPCb) in the ovary. In this study, we raised antibodies against these four proteins to identify their locations using immunohistochemistry. Our results suggest that inner layer I is constructed primarily of HgZPBa and Ca, whereas inner layer II consists primarily of HgZPBa. HgZPBb and Cb were minor components of the envelope. Therefore, the egg envelope of Pacific herring is primarily composed of liver-synthesized ZP proteins. A comparison of the thickness of the fertilized egg envelopes of 55 species suggested that egg envelopes derived from liver-synthesized ZP proteins tended to be thicker in demersal eggs than those in pelagic eggs, whereas egg envelopes derived from ovarian-synthesized ZP proteins had no such tendency. Our comparison suggests that the prehatching period of an egg with a thick egg envelope is longer than that of an egg with a thin egg envelope. We hypothesized that acquisition of liver-synthesized ZP proteins during evolution conferred the ability to develop a thick egg envelope, which allowed species with demersal eggs to adapt to mechanical stress in the prehatching environment by thickening the egg envelope, while pelagic egg envelopes have remained thin. © 2017 Wiley Periodicals, Inc.

Initial experience with a donor egg bank.

PubMed

Akin, James W; Bell, Katrina A; Thomas, Diana; Boldt, Jeffrey

2007-08-01

To report on the establishment of a commercial donor egg bank (CryoEggs International, LP) and to present our initial experience from the first four patients to receive eggs. Case report. Private fertility clinic. The four recipient women were aged 43, 43, 40, and 33 years. All had cycle day FSH levels greater than 25 mIU/mL. All were given the option of fresh donor egg IVF but opted to use frozen donor oocytes. Purchased and quarantined frozen donor eggs were thawed and inseminated using intracytoplasmic sperm injection (ICSI). Subsequent embryos were transferred on day 3. Clinical pregnancy as defined by presence of cardiac activity. There was a thawed egg survival rate of 76%, a fertilization rate of 74%, a pregnancy rate (PR) of 50%, with an average of 2.75 embryos per transfer and an implantation rate of 27%. Although very preliminary, these results indicate that more widespread use of frozen donor eggs obtained from a commercial egg bank may be feasible in the future, changing the landscape of donor egg IVF.

Sea urchin egg fertilization and development

NASA Technical Reports Server (NTRS)

Young, R. S.

1971-01-01

The effects of subgravity (much less than unit gravity) on fertilization, cell division, differentiation, and growth of a relatively simple biological system (eggs of the sea urchin Arbacia punctulata) were considered. The experiment was flown on Gemini 3 and recovered as scheduled. However, the experiment objectives were not achieved, primarily for mechanical reasons.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandler, D.P.; Welt, M.; Leung, F.C.

An efficient one-step injection technique for gene insertion into fertilized rainbow trout (Oncorhynchus mykiss) eggs is described, and basic parameters affecting egg survival are reported. Freshly fertilized rainbow trout eggs were injected in the perivitelline space with a recombinant mouse metallothionein-genomic bovine growth hormone (bGH) DNA construct using a 30-gauge hypodermic needle and a standard microinjection system. Relative to control, site of injection and DNA concentration did not affect the egg survival, but injections later than 3--4 hours post fertilization were detrimental. The injection technique permitted treatment of 100 eggs/hr with survivals up to 100%, resulting in a 4% DNAmore » uptake rate as indicated by DNA dot blot analysis. Positive dot blot results also indicated that the injected DNA is able to cross the vitelline membrane and persist for 50--60 days post hatching, obviating the need for direct injection into the germinal disk. Results are consistent with previous transgenic fish work, underscoring the usefulness of the technique for generating transgenic trout and salmonids. 24 refs., 6 figs., 3 tabs.« less

Extracellular Ca2+ Is Required for Fertilization in the African Clawed Frog, Xenopus laevis

PubMed Central

Duray, Alexis M.; Tembo, Maiwase; Beleny, David O.; Napolitano, Marc A.; Sauer, Monica L.; Wisner, Bennett W.

2017-01-01

Background The necessity of extracellular Ca2+ for fertilization and early embryonic development in the African clawed frog, Xenopus laevis, is controversial. Ca2+ entry into X. laevis sperm is reportedly required for the acrosome reaction, yet fertilization and embryonic development have been documented to occur in high concentrations of the Ca2+ chelator BAPTA. Here we sought to resolve this controversy. Methodology/principal finding Using the appearance of cleavage furrows as an indicator of embryonic development, we found that X. laevis eggs inseminated in a solution lacking added divalent cations developed normally. By contrast, eggs inseminated in millimolar concentrations of BAPTA or EGTA failed to develop. Transferring embryos to varying solutions after sperm addition, we found that extracellular Ca2+ is specifically required for events occurring within the first 30 minutes after sperm addition, but not after. We found that the fluorescently stained sperm were not able to penetrate the envelope of eggs inseminated in high BAPTA, whereas several had penetrated the vitelline envelope of eggs inseminated without a Ca2+ chelator, or with BAPTA and saturating CaCl2. Together these results indicate that fertilization does not occur in high concentrations of Ca2+ chelators. Finally, we found that the jelly coat includes >5 mM of readily diffusible Ca2+. Conclusions/Significance Taken together, these data are consistent with requirement of extracellular Ca2+ for fertilization. Based on our findings, we hypothesize that the jelly coat surrounding the egg acts as a reserve of readily available Ca2+ ions to foster fertilization in changing extracellular milieu. PMID:28114360

Signal transduction at fertilization: the Ca2+ release pathway in echinoderms and other invertebrate deuterostomes.

PubMed

Townley, Ian K; Roux, Michelle M; Foltz, Kathy R

2006-04-01

Gamete interaction and fusion triggers a number of events that lead to egg activation and development of a new organism. A key event at fertilization is the rise in intracellular calcium. In deuterostomes, this calcium is released from the egg's endoplasmic reticulum and is necessary for proper activation. This article reviews recent data regarding how gamete interaction triggers the initial calcium release, focusing on the echinoderms (invertebrate deuterostomes) as model systems. In eggs of these animals, Src-type kinases and phospholipase C-gamma are required components of the initial calcium trigger pathway in eggs.

PTK2b function during fertilization of the mouse oocyte

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Jinping; McGinnis, Lynda K.; Carlton, Carol

Highlights: • PTK2b is expressed in oocytes and is activated following fertilization. • PTK2b suppression in oocytes prevents fertilization, but not parthenogenetic activation. • PTK2b suppression prevents the oocyte from fusing with or incorporating bound sperm. • PTK2b suppressed oocytes that fail to fertilize do not exhibit calcium oscillations. - Abstract: Fertilization triggers rapid changes in intracellular free calcium that serve to activate multiple signaling events critical to the initiation of successful development. Among the pathways downstream of the fertilization-induced calcium transient is the calcium-calmodulin dependent protein tyrosine kinase PTK2b or PYK2 kinase. PTK2b plays an important role in fertilizationmore » of the zebrafish oocyte and the objective of the present study was to establish whether PTK2b also functions in mammalian fertilization. PTK2b was activated during the first few hours after fertilization of the mouse oocyte during the period when anaphase resumption was underway and prior to the pronuclear stage. Suppression of PTK2b kinase activity in oocytes blocked sperm incorporation and egg activation although sperm-oocyte binding was not affected. Oocytes that failed to incorporate sperm after inhibitor treatment showed no evidence of a calcium transient and no evidence of anaphase resumption suggesting that egg activation did not occur. The results indicate that PTK2b functions during the sperm-egg fusion process or during the physical incorporation of sperm into the egg cytoplasm and is therefore critical for successful development.« less

Avian models in teratology and developmental toxicology.

PubMed

Smith, Susan M; Flentke, George R; Garic, Ana

2012-01-01

The avian embryo is a long-standing model for developmental biology research. It also has proven utility for toxicology research both in ovo and in explant culture. Like mammals, avian embryos have an allantois and their developmental pathways are highly conserved with those of mammals, thus avian models have biomedical relevance. Fertile eggs are inexpensive and the embryo develops rapidly, allowing for high-throughput. The chick genome is sequenced and significant molecular resources are available for study, including the ability for genetic manipulation. The absence of a placenta permits the direct study of an agent's embryotoxic effects. Here, we present protocols for using avian embryos in toxicology research, including egg husbandry and hatch, toxicant delivery, and assessment of proliferation, apoptosis, and cardiac structure and function.

Effects of lead on the male mouse as investigated by in vitro fertilization and blastocyst culture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johansson, L.; Sjoeblom, P.; Wide, M.

1987-02-01

Long-term exposure of male mice to inorganic lead (lead chloride, 1 g/liter) in the drinking water reduces their fertility. The cause of this reduction, expressed as a decrease in the number of mated females showing inplantations, was investigated, using an in vivo fertilization method. It was found that spermatozoa from lead-exposed males had a significantly lower ability to fertilize mouse eggs than those from unexposed males. Preimplantation embryos, isolated from uterine horns of mice mated with lead-exposed males. Preimplantation embryos, isolated from uterine horns of mice mated with lead-exposed males, were examined. No morphologically abnormal embryos were found. However, whenmore » cultured in vitro over the implantation period, blastocysts of the group mated with lead-exposed males showed an increased frequency of delayed hatching from the zona pellucida or an inability to hatch. Among blastocysts from this group a decreased frequency of inner cell mass development was also found.« less

The timing of cortical granule fusion, content dispersal, and endocytosis during fertilization of the hamster egg: an electrophysiological and histochemical study.

PubMed

Kline, D; Stewart-Savage, J

1994-03-01

To determine the temporal relationship between cortical granule exocytosis and the repetitive calcium transients, which are characteristic of mammalian fertilization, we monitored membrane addition from exocytosis during fertilization of hamster eggs. Continuous measurement of membrane capacitance by applying a 3.1-nA alternating current at 375 Hz showed addition of cortical granule membrane. Simultaneous measurement of membrane potential revealed each calcium transient by the appearance of transient hyperpolarizing responses due to calcium-activated potassium channels in the egg. The initial membrane capacitance of the eggs averaged 736 +/- 44 pF (mean +/- SD; n = 7) and an increase in capacitance of 61 +/- 19 pF occurred within 4 sec of the start of the first hyperpolarizing response (HR) after fertilization. Immediately after the first increase in capacitance there was a gradual decline in membrane capacitance in all eggs and in five/seven eggs the capacitance returned to the unfertilized level in 7.8 +/- 4.4 min. The gradual decline in capacitance after the first increase indicated endocytosis, which was confirmed by the internalization of fluorescently labeled dextran. Superimposed on the gradual decline in membrane capacitance were smaller increases in capacitance that occurred with the second and later HRs. The total increase in capacitance from the first three events averaged 72 +/- 19 pF, representing an average increase in capacitance of about 10% of the capacitance of the unfertilized egg. By labeling eggs before and after permeabilization with two different fluorochromes attached to Lens culinaris agglutinin, we demonstrate that the dispersal of the cortical granules contents does not occur immediately after exocytosis. Our results demonstrate that cortical granule exocytosis in hamster eggs is closely coupled to the periodic increases in calcium, that the contents of the cortical granules are slow to disperse, and that after exocytosis, the surface area of the egg returns to the unfertilized level because of a period of endocytosis.

Artificial insemination of cranes with frozen semen

USGS Publications Warehouse

Gee, G.F.; Sexton, T.J.; Lewis, J.C.

1979-01-01

For the first time (1978) artificial insemination (AI) with frozen greater sandhill crane (Grus canadensis tabida) semen resulted in fertile eggs and chicks. During the 2 year (1977-78) study, 6 of 27 eggs produced were fertile. Three chicks hatched. Semen samples used for insemination were frozen and stored in liquid nitrogen for two months or less. Recent improvements in the laboratory indicated that a more effective sample can be prepared and greater fertility rates should be expected.

Effects of fertilization of four hemlock species on Adelges tsugae (Hemiptera: Adelgidae) growth and feeding preference of predators.

PubMed

Joseph, S V; Braman, S K; Hanula, J L

2011-02-01

Understanding how fertilization affects host resistance to hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), is important because fertilizers are often used to grow resistant selections to a suitable size for testing. We evaluated four hemlock species (Tsuga) under three different fertilizer regimes to assess whether fertility affected resistance to the adelgid and to determine whether it affected feeding preferences of the adelgid predators Laricobius nigrinus Fender and Sasajiscymnus tsugae (Sasaji & McClure). Treatments were long-term fertilization (from June 2008 to June 2009), short-term fertilization (from March to June 2009), and no fertilizer. Fertilizer was applied biweekly with 240 ppm N by using water-soluble fertilizer (N-P-K, 20:20:20). Plants (>1 yr old) were artificially infested with adelgids on 31 March 2009. Among unfertilized hemlocks (n=10 per species), foliar N was highest in Tsuga mertensiana (Bong.) CarriBre and lowest in T. chinensis (Franch.) E. Pritz. Significantly more progredien ovisacs or sisten eggs were present on T. mertensiana than on the other hemlock species with none on unfertilized T. chinensis. A. tsugae adults on T. heterophylla (Raf.) Sarg. were unaffected by fertility, but densities of developing A. tsugae nymphs were higher on unfertilized T. heterophylla plants than on fertilized T. heterophylla plants regardless of fertilizer treatment. Both L. nigrinus and S. tsugae consumed more adelgid eggs that developed on fertilized T. canadensis than from unfertilized plants. The predators did not exhibit this preference for adelgid eggs from females that developed on T. heterophylla or T. mertensiana.

Distribution of fluorescently labeled tubulin injected into sand dollar eggs from fertilization through cleavage.

PubMed

Hamaguchi, Y; Toriyama, M; Sakai, H; Hiramoto, Y

1985-04-01

Porcine brain tubulin labeled with fluorescein isothiocyanate (FITC) was able to polymerize by itself and co-polymerize with tubulin purified from starfish sperm flagella. When we injected the FITC-labeled tubulin into unfertilized eggs of the sand dollar, Clypeaster japonicus, and the eggs were then fertilized, the labeled tubulin was incorporated into the sperm aster. When injected into fertilized eggs at streak stage, the tubulin was quickly incorporated into each central region of growing asters. It was clearly visualized that the labeled tubulin, upon reaching metaphase, accumulated in the mitotic apparatus and later disappeared over the cytoplasm during interphase. The accumulation of the fluorescence in the mitotic apparatus was observed repeatedly at successive cleavage. After lysis of the fertilized eggs with a microtubule-stabilizing solution, fluorescent fibrous structures around the nucleus and those of the sperm aster and the mitotic apparatus were preserved and coincided with the fibrous structures observed by polarization and differential interference microscopy. We found the FITC-labeled tubulin to be incorporated into the entire mitotic apparatus within 20-30 s when injected into the eggs at metaphase or anaphase. This rapid incorporation of the labeled tubulin into the mitotic apparatus suggests that the equilibrium between mitotic microtubules and tubulin is attained very rapidly in the living eggs. Axonemal tubulin purified from starfish sperm flagella and labeled with FITC was also incorporated into microtubular structures in the same fashion as the FITC-labeled brain tubulin. These results suggest that even FITC-labeled heterogeneous tubulins undergo spatial and stage-specific regulation of assembly-disassembly in the same manner as does sand dollar egg tubulin.

Distribution of fluorescently labeled tubulin injected into sand dollar eggs from fertilization through cleavage

PubMed Central

1985-01-01

Porcine brain tubulin labeled with fluorescein isothiocyanate (FITC) was able to polymerize by itself and co-polymerize with tubulin purified from starfish sperm flagella. When we injected the FITC- labeled tubulin into unfertilized eggs of the sand dollar, Clypeaster japonicus, and the eggs were then fertilized, the labeled tubulin was incorporated into the sperm aster. When injected into fertilized eggs at streak stage, the tubulin was quickly incorporated into each central region of growing asters. It was clearly visualized that the labeled tubulin, upon reaching metaphase, accumulated in the mitotic apparatus and later disappeared over the cytoplasm during interphase. The accumulation of the fluorescence in the mitotic apparatus was observed repeatedly at successive cleavage. After lysis of the fertilized eggs with a microtubule-stabilizing solution, fluorescent fibrous structures around the nucleus and those of the sperm aster and the mitotic apparatus were preserved and coincided with the fibrous structures observed by polarization and differential interference microscopy. We found the FITC-labeled tubulin to be incorporated into the entire mitotic apparatus within 20-30 s when injected into the eggs at metaphase or anaphase. This rapid incorporation of the labeled tubulin into the mitotic apparatus suggests that the equilibrium between mitotic microtubules and tubulin is attained very rapidly in the living eggs. Axonemal tubulin purified from starfish sperm flagella and labeled with FITC was also incorporated into microtubular structures in the same fashion as the FITC-labeled brain tubulin. These results suggest that even FITC-labeled heterogeneous tubulins undergo spatial and stage-specific regulation of assembly-disassembly in the same manner as does sand dollar egg tubulin. PMID:3920225

Effects of Nosema fumiferanae (Microsporida) on Fecundity, Fertility, and Progeny Performance of Choristoneura fumiferana (Lepidoptera: Tortricidae)

Treesearch

Leah S. Bauer; Gerald L. Nordin

1989-01-01

Female eastern spruce budworm, Choristoneura fumiferana (Clemens), inoculated sublethally as fourth or fifth instars with Nosema fumiferanae (Thomson), exhibited significant reductions in size, fecundity, and total egg complement. Mating success and egg fertility were similar for treated and control insects. The presence of disease...

9 CFR 93.903 - Import permits for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Import permits for live fish... ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN ANIMAL, BIRD, AND... General Provisions for Svc-Regulated Fish Species § 93.903 Import permits for live fish, fertilized eggs...

9 CFR 93.903 - Import permits for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Import permits for live fish... ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN ANIMAL, BIRD, AND... General Provisions for Svc-Regulated Fish Species § 93.903 Import permits for live fish, fertilized eggs...

9 CFR 93.903 - Import permits for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Import permits for live fish... ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN ANIMAL, BIRD, AND... General Provisions for Svc-Regulated Fish Species § 93.903 Import permits for live fish, fertilized eggs...

Atlantic salmon eggs favour sperm in competition that have similar major histocompatibility alleles.

PubMed

Yeates, Sarah E; Einum, Sigurd; Fleming, Ian A; Megens, Hendrik-Jan; Stet, René J M; Hindar, Kjetil; Holt, William V; Van Look, Katrien J W; Gage, Matthew J G

2009-02-07

Polyandry and post-copulatory sexual selection provide opportunities for the evolution of female differential sperm selection. Here, we examined the influence of variation in major histocompatibility (MH) class I allelic composition upon sperm competition dynamics in Atlantic salmon. We ran in vitro fertilization competitions that mimicked the gametic microenvironment, and replicated a paired-male experimental design that allowed us to compare differences in sperm competition success among males when their sperm compete for eggs from females that were genetically either similar or dissimilar at the MH class I locus. Concurrently, we measured variation in spermatozoal traits that are known to influence relative fertilization success under these conditions. Contrary to the findings demonstrating mechanisms that promote MH complex heterozygosity, our results showed that males won significantly greater relative fertilization success when competing for eggs from genetically similar females at the MH class I. This result also showed covariation with the known influences of sperm velocity on relative fertilization success. We discuss these unexpected findings in relation to sperm-egg recognition and hybridization avoidance mechanisms based upon immunogenetic variation.

Assessing the potential for egg chemoattractants to mediate sexual selection in a broadcast spawning marine invertebrate

PubMed Central

Evans, Jonathan P.; Garcia-Gonzalez, Francisco; Almbro, Maria; Robinson, Oscar; Fitzpatrick, John L.

2012-01-01

In numerous species, egg chemoattractants play a critical role in guiding sperm towards unfertilized eggs (sperm chemotaxis). Until now, the known functions of sperm chemotaxis include increasing the effective target size of eggs, thereby promoting sperm–egg encounters, and facilitating species recognition. Here, we report that in the broadcast spawning mussel, Mytilus galloprovincialis, egg chemoattractants may play an unforeseen role in sexual selection by enabling sperm to effectively ‘choose’ between the eggs of different conspecific females. In an initial experiment, we confirmed that sperm chemotaxis occurs in M. galloprovincialis by showing that sperm are attracted towards unfertilized eggs when given the choice of eggs or no eggs in a dichotomous chamber. We then conducted two cross-classified mating experiments, each comprising the same individual males and females crossed in identical male × female combinations, but under experimental conditions that offered sperm ‘no-choice’ (each fertilization trial took place in a Petri dish and involved a single male and female) or a ‘choice’ of a female's eggs (sperm were placed in the centre of a dichotomous choice chamber and allowed to choose eggs from different females). We show that male-by-female interactions characterized fertilization rates in both experiments, and that there was remarkable consistency between patterns of sperm migration in the egg-choice experiment and fertilization rates in the no-choice experiment. Thus, sperm appear to exploit chemical cues to preferentially swim towards eggs with which they are most compatible during direct sperm-to-egg encounters. These results reveal that sperm differentially select eggs on the basis of chemical cues, thus exposing the potential for egg chemoattractants to mediate mate choice for genetically compatible partners. Given the prevalence of sperm chemotaxis across diverse taxa, our findings may have broad implications for sexual selection in other mating systems. PMID:22438495

Roles of calcium and pH in activation of eggs of the medaka fish, Oryzias latipes

PubMed Central

1983-01-01

Unfertilized eggs of the medaka fish (Oryzias latipes) were injected with pH-buffered calcium buffers. Medaka egg activation is accompanied by a transient increase in cytoplasmic free calcium (Gilkey, J. C., L. F. Jaffe, E. B. Ridgway, and G. T. Reynolds, 1978, J. Cell Biol., 76:448-466). The calcium buffer injections demonstrated that (a) the threshold free calcium required to elicit the calcium transient and activate the egg is between 1.7 and 5.1 microM at pH 7.0, well below the 30 microM reached during the transient, and (b) buffers which hold free calcium below threshold prevent activation of the buffered region in subsequently fertilized eggs. Therefore an increase in free calcium is necessary and sufficient to elicit the calcium transient, and the calcium transient is necessary to activate the egg. Further, these results are additional proof that the calcium transient is initiated and propagated through the cytoplasm by a mechanism of calcium- stimulated calcium release. Finally, a normal calcium transient must propagate through the entire cytoplasm to ensure normal development. Unfertilized eggs were injected with pH buffers to produce short-term, localized changes in cytoplasmic pH. The eggs were then fertilized at various times after injection. In other experiments, unfertilized and fertilized eggs were exposed to media containing either NH4Cl or CO2 to produce longer term, global changes in cytoplasmic pH. These treatments neither activated the eggs nor interfered with the normal development of fertilized eggs, suggesting that even if a natural change in cytoplasmic pH is induced by activation, it has no role in medaka egg development. The injected pH buffers altered the rate of propagation of the calcium transient through the cytoplasm, suggesting that the threshold free calcium required to trigger calcium-stimulated calcium release might be pH dependent. The results of injection of pH-buffered calcium buffers support this conjecture: for a tenfold increase in hydrogen ion concentration, free calcium must also be raised tenfold to elicit the calcium transient. PMID:6411737

Effects of egg quality and method of incubation on the hatching success of channel X blue hybrid catfish eggs

USDA-ARS?s Scientific Manuscript database

The objective of this study was to evaluate the effects of egg quality of stripped eggs from channel catfish (Ictalurus punctatus) and method of incubation of fertilized hybrid catfish eggs on hatching success. Stripped eggs from 17 channel catfish females were evaluated in a 2 x 2 factorial...

Development of a convenient in vitro fertilization method using interspecific hybrids between Oryzias latipes and Oryzias curvinotus.

PubMed

Kamei, Yasuhiro; Itou, Junji; Oda, Shoji; Masui, Mami; Kim, Jin-Hyeong; Ishikawa, Tomoko; Yuba, Shunsuke; Kinoshita, Masato; Mitani, Hiroshi; Todo, Takeshi

2007-12-01

Medaka is a small Asian freshwater teleost and has been an excellent model for fertilization studies for more than 50 years. Therefore, experimental procedures for in vitro fertilization (IVF) and cryopreservation of sperm are well established. In contrast, since the eggs or early embryos can not be cryopreserved, many females are killed to obtain unfertilized eggs for IVF. Recent progress in genomics is establishing medaka as a new model animal in functional genomics, and numerous mutant and transgenic strains have been established and stored as frozen sperm. Accumulated preserved resources require a simple and reliable recovery method for IVF. In this paper, we describe a method for obtaining a large number of unfertilized eggs without killing females, using sterile interspecific hybrids between Oryzias latipes and O. curvinotus. However, there is no report about the normality of offspring that were obtained by IVF using unfertilized eggs spawned in mating with the sterile hybrid male. In this paper, we have confirmed the reliability of the method regarding the influences on the next generation and also assessed conditions for efficient collection of unfertilized eggs. The method would be useful not only for fertilization studies but also for keeping transgenics and mutants, including a mutant library for a reverse genetic approach.

Comparison of diluents for holding cock semen six hours at 41 C.

PubMed

Howarth, B

1983-06-01

Beltsville Poultry Semen Extender (BPSE) and Lake's Diluent A (LDA) were compared with minimum essential medium (MEM) for their ability to maintain the fertilizing capacity of cock semen held 6 hr at 41 C. Motility significantly declined from the beginning to the end of the holding period for semen in BPSE and LDA. Only in LDA, however, were the number of live spermatozoa significantly reduced. Although there were no differences in oxygen (O2) consumption measured at 1 and 6 hr for semen in BPSE and MEM, a significant reduction in O2 consumption was observed between these time periods for semen in LDA. Fertility of semen held in MEM (90.3%) was significantly higher than the unstored control semen (82.9%) and semen held in either BPSE (3.5%) or LDA (1.9%). No differences in hatchability of fertile eggs were observed between the semen groups.

Is the idea of a fast block to polyspermy based on artifact?

PubMed

Dale, Brian

2014-08-01

This purpose of this review is to look at the experimental evidence, both kinetic and electrophysiological, that led to the hypothesis of a fast electrical block to polyspermy in sea urchin eggs. The idea of a fast partial block, forwarded in the 1950's, that would reduce the receptivity of the egg surface by 1/20th following its interaction with the fertilizing spermatozoon, was based on experiments that treated fertilization as a first order chemical reaction. Here, I outline the criticisms of the Rothschild theory and demonstrate that the hypothesis of a fast partial block to polyspermy is unfounded. Notwithstanding, it was suggested in the 1970's that the membrane depolarization, induced by the fertilizing spermatozoon, prevented the interaction of supernumerary spermatozoa, the fast electrical block to polyspermy. While trans-membrane voltage recording has permitted a better understanding of the sequence of events occurring at fertilization, there is no evidence that depolarization prevents the interaction of supernumerary spermatozoa. Sperm entry is prevented at positive and negative potentials, in the voltage clamp configuration, however this is an artifact caused by the currents injected into the egg employed to hold the voltage constant in a non-physiological range. At permissive voltages, around -20 mV, where the current required to hold the voltage is minimal, only one spermatozoon normally enters the egg. Thus, irrespective of the egg voltage, the fertilizing spermatozoon is, in any case, attached to a privileged interaction site that permits entry and distinguishes it from supernumerary spermatozoa. Competence for monospermy is acquired during oocyte maturation and data on cortical organization in echinoderm eggs points to the actin filament system for regulating sperm entry. Copyright © 2014 Elsevier Inc. All rights reserved.

Activin Decoy Receptor ActRIIB:Fc Lowers FSH and Therapeutically Restores Oocyte Yield, Prevents Oocyte Chromosome Misalignments and Spindle Aberrations, and Increases Fertility in Midlife Female SAMP8 Mice.

PubMed

Bernstein, Lori R; Mackenzie, Amelia C L; Lee, Se-Jin; Chaffin, Charles L; Merchenthaler, István

2016-03-01

Women of advanced maternal age (AMA) (age ≥ 35) have increased rates of infertility, miscarriages, and trisomic pregnancies. Collectively these conditions are called "egg infertility." A root cause of egg infertility is increased rates of oocyte aneuploidy with age. AMA women often have elevated endogenous FSH. Female senescence-accelerated mouse-prone-8 (SAMP8) has increased rates of oocyte spindle aberrations, diminished fertility, and rising endogenous FSH with age. We hypothesize that elevated FSH during the oocyte's FSH-responsive growth period is a cause of abnormalities in the meiotic spindle. We report that eggs from SAMP8 mice treated with equine chorionic gonadotropin (eCG) for the period of oocyte growth have increased chromosome and spindle misalignments. Activin is a molecule that raises FSH, and ActRIIB:Fc is an activin decoy receptor that binds and sequesters activin. We report that ActRIIB:Fc treatment of midlife SAMP8 mice for the duration of oocyte growth lowers FSH, prevents egg chromosome and spindle misalignments, and increases litter sizes. AMA patients can also have poor responsiveness to FSH stimulation. We report that although eCG lowers yields of viable oocytes, ActRIIB:Fc increases yields of viable oocytes. ActRIIB:Fc and eCG cotreatment markedly reduces yields of viable oocytes. These data are consistent with the hypothesis that elevated FSH contributes to egg aneuploidy, declining fertility, and poor ovarian response and that ActRIIB:Fc can prevent egg aneuploidy, increase fertility, and improve ovarian response. Future studies will continue to examine whether ActRIIB:Fc works via FSH and/or other pathways and whether ActRIIB:Fc can prevent aneuploidy, increase fertility, and improve stimulation responsiveness in AMA women.

Parthenogenetic embryos from unfertilized Chinese painted quail eggs alter albumen pH, gases, and ion concentrations during incubation.

PubMed

Santa Rosa, P; Parker, H M; Kiess, A S; McDaniel, C D

2016-01-15

Parthenogenesis is a form of embryonic development that occurs without fertilization. Recently, parthenogenesis has been reported in Chinese painted quail eggs. In Japanese quail, it has been shown that albumen pH of incubated fertile eggs is lower than that of incubated infertile eggs. However, it is unknown if alterations, similar to those in incubated fertile eggs, occur in albumen pH, gases, or ion concentrations from unfertilized eggs exhibiting parthenogenetic development. Therefore, the objective of this study was to determine if any differences in pH, gases, or ion concentrations exist between incubated unfertilized eggs exhibiting parthenogenetic development versus unfertilized eggs with no development over incubation. In this study, eggs were collected daily from Chinese painted quail hens that were separated from males at 4 weeks of age, before sexual maturity. Eggs were stored for 0 to 3 days at 20 °C and incubated at 37.5 °C for 12 days. Eggs were weighed before and after incubation to obtain percentage egg weight loss. After incubation, embryo size and albumen O2, CO2, Ca(2+), Na(+), and Cl(-) concentrations as well as pH were obtained from each incubated egg. Over incubation, albumen from unfertilized eggs exhibiting parthenogenetic development had a lower pH as well as less O2 and Cl(-), yet a higher Ca(2+) and Na(+) concentration as compared with the albumen of unfertilized eggs with no development. Also, eggs exhibiting parthenogenetic development had a higher albumen CO2 concentration as compared with eggs without development. The rate of egg weight loss was much lower in eggs exhibiting parthenogenetic development as compared with eggs without development. Also, as parthenogen size increased, there was a decrease in albumen pH, O2, and Cl(-), yet an increase in CO2 and Ca(2+). In conclusion, it appears that, over incubation, parthenogenetic development from unfertilized eggs alters the composition of albumen as compared with the albumen from unfertilized eggs with no parthenogenetic development. Published by Elsevier Inc.

Subcellular Metabolite and Lipid Analysis of Xenopus laevis Eggs by LAESI Mass Spectrometry

PubMed Central

Reschke, Brent R.; Henderson, Holly D.; Powell, Matthew J.; Moody, Sally A.; Vertes, Akos

2014-01-01

Xenopus laevis eggs are used as a biological model system for studying fertilization and early embryonic development in vertebrates. Most methods used for their molecular analysis require elaborate sample preparation including separate protocols for the water soluble and lipid components. In this study, laser ablation electrospray ionization (LAESI), an ambient ionization technique, was used for direct mass spectrometric analysis of X. laevis eggs and early stage embryos up to five cleavage cycles. Single unfertilized and fertilized eggs, their animal and vegetal poles, and embryos through the 32-cell stage were analyzed. Fifty two small metabolite ions, including glutathione, GABA and amino acids, as well as numerous lipids including 14 fatty acids, 13 lysophosphatidylcholines, 36 phosphatidylcholines and 29 triacylglycerols were putatively identified. Additionally, some proteins, for example thymosin β4 (Xen), were also detected. On the subcellular level, the lipid profiles were found to differ between the animal and vegetal poles of the eggs. Radial profiling revealed profound compositional differences between the jelly coat vitelline/plasma membrane and egg cytoplasm. Changes in the metabolic profile of the egg following fertilization, e.g., the decline of polyamine content with the development of the embryo were observed using LAESI-MS. This approach enables the exploration of metabolic and lipid changes during the early stages of embryogenesis. PMID:25506922

Subcellular metabolite and lipid analysis of Xenopus laevis eggs by LAESI mass spectrometry.

PubMed

Shrestha, Bindesh; Sripadi, Prabhakar; Reschke, Brent R; Henderson, Holly D; Powell, Matthew J; Moody, Sally A; Vertes, Akos

2014-01-01

Xenopus laevis eggs are used as a biological model system for studying fertilization and early embryonic development in vertebrates. Most methods used for their molecular analysis require elaborate sample preparation including separate protocols for the water soluble and lipid components. In this study, laser ablation electrospray ionization (LAESI), an ambient ionization technique, was used for direct mass spectrometric analysis of X. laevis eggs and early stage embryos up to five cleavage cycles. Single unfertilized and fertilized eggs, their animal and vegetal poles, and embryos through the 32-cell stage were analyzed. Fifty two small metabolite ions, including glutathione, GABA and amino acids, as well as numerous lipids including 14 fatty acids, 13 lysophosphatidylcholines, 36 phosphatidylcholines and 29 triacylglycerols were putatively identified. Additionally, some proteins, for example thymosin β4 (Xen), were also detected. On the subcellular level, the lipid profiles were found to differ between the animal and vegetal poles of the eggs. Radial profiling revealed profound compositional differences between the jelly coat vitelline/plasma membrane and egg cytoplasm. Changes in the metabolic profile of the egg following fertilization, e.g., the decline of polyamine content with the development of the embryo were observed using LAESI-MS. This approach enables the exploration of metabolic and lipid changes during the early stages of embryogenesis.

Amphibian fertilization and development in microgravity

NASA Technical Reports Server (NTRS)

Souza, K. A.; Black, S. D.

1985-01-01

An experiment investigating the effects of gravity on embryonic development in amphibians is proposed. The planned procedures for the preparation of the frog eggs for launching in the Space Shuttle, for the injection of the eggs with gonadotropin, for the insertion of the eggs into egg chambers, for the storage of one of the chambers in a microgravity area and the second into a centrifuge, and for the fertilization of the eggs are described. The later organogenesis, swimming behavior, cytoplasmic components, cellular formation, neural plate and archenteron expansion, and allometry and expansion of the organ systems will be examined. Normal morphology for embryos and tadpoles developing at microgravity and the formation of the neural plate opposite the sperm entry point meridian are predicted.

Importance of sperm morphology during sperm transport and fertilization in mammals.

PubMed

García-Vázquez, Francisco A; Gadea, Joaquín; Matás, Carmen; Holt, William V

2016-01-01

After natural or artificial insemination, the spermatozoon starts a journey from the site of deposition to the place of fertilization. However, only a small subset of the spermatozoa deposited achieves their goal: to reach and fertilize the egg. Factors involved in controlling sperm transport and fertilization include the female reproductive tract environment, cell-cell interactions, gene expression, and phenotypic sperm traits. Some of the significant determinants of fertilization are known (i.e., motility or DNA status), but many sperm traits are still indecipherable. One example is the influence of sperm dimensions and shape upon transport within the female genital tract towards the oocyte. Biophysical associations between sperm size and motility may influence the progression of spermatozoa through the female reproductive tract, but uncertainties remain concerning how sperm morphology influences the fertilization process, and whether only the sperm dimensions per se are involved. Moreover, such explanations do not allow the possibility that the female tract is capable of distinguishing fertile spermatozoa on the basis of their morphology, as seems to be the case with biochemical, molecular, and genetic properties. This review focuses on the influence of sperm size and shape in evolution and their putative role in sperm transport and selection within the uterus and the ability to fertilize the oocyte.

Importance of sperm morphology during sperm transport and fertilization in mammals

PubMed Central

García-Vázquez, Francisco A; Gadea, Joaquín; Matás, Carmen; Holt, William V

2016-01-01

After natural or artificial insemination, the spermatozoon starts a journey from the site of deposition to the place of fertilization. However, only a small subset of the spermatozoa deposited achieves their goal: to reach and fertilize the egg. Factors involved in controlling sperm transport and fertilization include the female reproductive tract environment, cell-cell interactions, gene expression, and phenotypic sperm traits. Some of the significant determinants of fertilization are known (i.e., motility or DNA status), but many sperm traits are still indecipherable. One example is the influence of sperm dimensions and shape upon transport within the female genital tract towards the oocyte. Biophysical associations between sperm size and motility may influence the progression of spermatozoa through the female reproductive tract, but uncertainties remain concerning how sperm morphology influences the fertilization process, and whether only the sperm dimensions per se are involved. Moreover, such explanations do not allow the possibility that the female tract is capable of distinguishing fertile spermatozoa on the basis of their morphology, as seems to be the case with biochemical, molecular, and genetic properties. This review focuses on the influence of sperm size and shape in evolution and their putative role in sperm transport and selection within the uterus and the ability to fertilize the oocyte. PMID:27624988

Influences of DMP on the Fertilization Process and Subsequent Embryogenesis of Abalone (Haliotis diversicolor supertexta) by Gametes Exposure

PubMed Central

Cai, Zhong-Hua

2011-01-01

Di-methyl phthalate (DMP), a typical endocrine disrupting chemical (EDC), is ubiquitously distributed in aquatic environments; yet studies regarding its impact on gametes and the resulting effects on embryogenesis in marine gastropods are relatively scarce. In this study, the influences of DMP on the gametes and subsequent developmental process of abalone (Haliotis diversicolor supertexta, a representative marine benthic gastropod) were assessed. Newborn abalone eggs and sperm were exposed separately to different DMP concentrations (1, 10 or 100 ppb) for 60 min. At the end-point of exposure, the DMP-treated eggs and sperm were collected for analysis of their ultra-structures, ATPase activities and total lipid levels, and the fertilized gametes (embryos) were collected to monitor related reproductive parameters (fertilization rate, abnormal development rate and hatching success rate). Treatment with DMP did not significantly alter the structure or total lipid content of eggs at any of the doses tested. Hatching failures and morphological abnormalities were only observed with the highest dose of DMP (100 ppb). However, DMP exposure did suppress sperm ATPase activities and affect the morphological character of their mitochondria. DMP-treated sperm exhibited dose-dependent decreases in fertilization efficiency, morphogenesis and hatchability. Relatively obvious toxicological effects were observed when both sperm and eggs were exposed to DMP. Furthermore, RT-PCR results indicate that treatment of gametes with DMP changed the expression patterns of physiologically-regulated genes (cyp3a, 17β-HSD-11 and 17β-HSD-12) in subsequent embryogenesis. Taken together, this study proofed that pre-fertilization exposure of abalone eggs, sperm or both to DMP adversely affects the fertilization process and subsequent embryogenesis. PMID:22028799

Behavior differentiation between wild Japanese quail, domestic quail, and their first filial generation.

PubMed

Chang, G B; Liu, X P; Chang, H; Chen, G H; Zhao, W M; Ji, D J; Chen, R; Qin, Y R; Shi, X K; Hu, G S

2009-06-01

The number of wild quail has dramatically reduced in China and reached a state of endangerment with the deterioration of the environment in recent years. In this study, we examined the ecological behaviors of quails in the cage to determine the differentiation level between wild Japanese quail and domestic quail, to detect the relationship between quail behavior and evolutionary differentiation and to analyze the possibility of restoring effective size of wild population. With the on-the-spot observations and measurements, the behaviors of 3 categories of quail, namely wild Japanese quail from the Weishan Lake area in China, domestic quail, and their first filial generation (F(1)) were studied. Domestic quail differed from wild Japanese quail in morphological pattern and ecological behaviors, including some indexes of figure type and egg, vocalization, aggression and fighting, and mating, but wild Japanese quail and domestic quail could succeed in mating and reproducing fertile hybrid offspring. There were significant differences between domestic quail and wild Japanese quail in reproductive traits, involved mating times, fertility rate, hatching rate, and hatching rate of fertilized eggs (P < 0.05). The first filial generation presented significant difference from the wild Japanese quail in vocalization, aggression and fighting, mating, hatching rate, hatching rate of fertilized eggs, and some egg indexes (P < 0.05) and significantly differ from the domestic quail in vocalization, hatching rate, and hatching rate of fertilized eggs (P < 0.05). Evolutionary differentiation between wild quail and domestic quail was still at a relatively low level because no reproductive isolation existed. The advantages of the F(1) hybrids in reproductive capacity, fertilization, and hatching recommend that releasing hybrids instead of domestic quails to the wild would be a more effective way to restore the effective size of wild quail population if necessary.

Incubation temperature and hemoglobin dielectric of chicken embryos incubated under the influence of electric field.

PubMed

Shafey, T M; Al-Batshan, H A; Shalaby, M I; Ghannam, M M

2006-01-01

Eggs from a layer-type breeder flock (Baladi, King Saud University) between 61 and 63 weeks of age were used in 3 trials to study the effects of electric field (EF) during incubation on the internal temperature of incubation, and eggs and hemoglobin (Hb) dielectric of chicken embryos at 18 days of age. Dielectric relative permittivity (epsilon') and conductivity (sigma) of Hb were examined in the range of frequency from 20 to 100 kHz. The values of dielectric increment (Deltaepsilon') and the relaxation times (tau) of Hb molecules were calculated. The internal temperature of eggs was measured in empty (following the removal of egg contents) and fertilized eggs in trials 1 and 2, respectively. The level of the EF was 30 kV/m, 60 Hz. EF incubation of embryos influenced the temperature of incubation and electrical properties of Hb molecules and did not influence the temperature of incubation and internal environment of eggs when empty eggs were incubated. EF incubation of fertilized eggs significantly raised the temperature of incubation, egg air cell, and at the surface of the egg yolk by approximately 0.09, 0.60, and 0.61 degrees F, respectively and Hb epsilon', sigma, Deltaepsilon', and tau as a function of the range of frequency of 20 to 100 kHz when compared with their counterparts of the control group. It was concluded that the exposure of fertilized chicken eggs to EF of 30 kV/m, 60 Hz, during incubation altered dielectric properties of Hb and that probably affected cell to cell communication and created the right environment for enhancing the growing process and heat production of embryos consequently increasing the temperature of the internal environment of the egg, and incubation.

-induced fertilization impairment in Strongylocentrotus droebachiensis collected in the Arctic

NASA Astrophysics Data System (ADS)

Bögner, D.; Bickmeyer, U.; Köhler, A.

2014-06-01

Fertilization depends on distribution and aggregation patterns of sea urchins which influence gamete contact time and may potentially enhance their vulnerability to ocean acidification. In this study, we conducted fertilization experiments to assess the effects of selected pH scenarios on fertilization success of Strongylocentrotus droebachiensis, from Spitsbergen, Arctic. Acidification was achieved by aerating seawater with different CO2 partial pressures to represent pre-industrial and present conditions (measured ~180-425 µatm) and future acidification scenarios (~550-800, ~1,300, ~2,000 µatm). Fertilization success was defined as the proportion of successful/unsuccessful fertilizations per treatment; eggs were classified according to features of their fertilization envelope (FE), hyaline layer (HL) and achievement of cellular division. The diagnostic findings of specific pathological aberrations were described in detail. We additionally measured intracellular pH changes in unfertilized eggs exposed for 1 h to selected acidification treatments using BCECF/AM. We conclude that (a) acidified conditions increase the proportion of eggs that failed fertilization, (b) acidification may increase the risk of polyspermy due to failures in the FE formation supported by the occasional observation of multiple sperms in the perivitelline space and (c) irregular formation of the embryo may arise due to impaired formation of the HL. The decrease in fertilization success could be also related to the observed changes in intracellular pH at pCO2 ~ 1,000 μatm or higher.

Female Fertility Issues

Cancer.gov

Fertility issues are common in women getting cancer treatment. Fertility preservation options include egg freezing, embryo freezing, ovarian tissue freezing, ovarian shielding and ovarian transposition. Resources, support, and clinical trials are listed.

Response of amphibian egg non-yolk cytoplasm to gravity orientation

NASA Technical Reports Server (NTRS)

Smith, R. C.; Neff, A. W.; Malacinski, G. M.

1985-01-01

In order to study amphibian egg cytoplasmic organization and egg symmetrization at the molecular level, a library of seventeen monoclonal antibodies (MoAbs) against Xenopus laevis non-yolk egg proteins was produced. Several of these MoAbs react with non-yolk cytoplasmic antigens which are unevenly distributed in the fertile Xenopus egg.

The integrin-binding motif RGDS induces protein tyrosine phosphorylation without activation in Bufo arenarum (Amphibia) oocytes.

PubMed

Mouguelar, Valeria S; Cabada, Marcelo O; Coux, Gabriela

2011-05-01

Integrins are cell adhesion molecules that are thought to be involved in sperm-oocyte interaction. Nevertheless, their function in mammalian fertilization is still controversial, as different species behave differently. In amphibians, their role is mainly supported by Xenopus laevis studies, where RGDS peptide induces oocyte activation. We recently provided evidence suggesting the presence and involvement of integrins in the interaction of the oocyte plasma membrane (PM) with sperm in the amphibian Bufo arenarum. In order to understand the role of integrin homologs in oocytes and their possible contribution to egg activation mechanisms, we examined the presence of integrin subunits and the effect of RGDS peptide on oocytes and during fertilization. Western blot studies detected integrin subunits α5, αV and β1 in oocytes. In sperm, we could detect only the αV integrin subunit. We found that RGDS peptide was unable to elicit egg activation or MAPK dephosphorylation, but can induce reversible inhibition of fertilization. A similar partial inhibition was produced by an anti-β1 integrin antibody. Using an anti-phosphotyrosine antibody we found major changes in phosphotyrosine-containing proteins in egg extracts minutes after fertilization. Cytosol and PMs isolated from oocytes and fertilized eggs showed additional fertilization-induced phosphorylated proteins. Some of these were also present in cytosol and PMs from RGDS-treated oocytes (partially mimicking fertilization). These findings suggest that B. arenarum fertilization involves integrins (e.g. β1 subunit) as adhesion proteins. Our data support the view that RGDS-binding receptors may function as signaling receptors in B. arenarum oocytes, but integrin engagement by RGDS is not sufficient for oocyte activation.

Humic Fertilizer and Vermicompost Applied to the Soil Can Positively Affect Population Growth Parameters of Trichogramma brassicae (Hymenoptera: Trichogrammatidae) on Eggs of Tuta absoluta (Lepidoptera: Gelechiidae).

PubMed

Mohamadi, P; Razmjou, J; Naseri, B; Hassanpour, M

2017-12-01

The tomato leaf miner, Tuta absoluta (Meyrick), is a devastating pest of tomato worldwide. One of the control measures of T. absoluta is the use of biological control agents, such as Trichogramma wasps. Interactions between natural enemies and insect pests may be affected by application of fertilizers, because changes in plant quality through the fertilizer application may therefore affect herbivore characteristics and suitability of them to parasitism. Laboratory tests were carried out to evaluate the life table parameters of Trichogramma brassicae Bezdenko on T. absoluta eggs reared on tomato plants treated either with vermicompost (40%), humic fertilizer (2 g/kg soil), or control (suitable mixture of field soil and sand). Population growth parameters of T. brassicae were affected by fertilizer treatments. Significant differences were found for immature life period and total fecundity of T. brassicae on the treatments. Differences of intrinsic rate of natural increase (r m ), finite rate of increase (λ), net reproductive rate (R 0 ), mean generation time (T), and doubling time (DT) of T. brassicae among treatments were also significant. The lowest values of r m , λ, and R 0 were recorded for T. brassicae developed on T. absoluta eggs on control treatment, whereas the highest values of these parameters were observed on 2 g/kg humic fertilizer. Furthermore, T. brassicae had the shortest T and DT values on 2 g/kg humic fertilizer and 40% vermicompost treatments. Our results showed that application of humic fertilizer and vermicompost could positively affect population growth parameters of T. brassicae on eggs of T. absoluta fed on tomato plants.

9 CFR 93.902 - Ports designated for the importation of live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2013 CFR

2013-01-01

... of live fish, fertilized eggs, and gametes. 93.902 Section 93.902 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN... Animal Species General Provisions for Svc-Regulated Fish Species § 93.902 Ports designated for the...

9 CFR 93.902 - Ports designated for the importation of live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2012 CFR

2012-01-01

... of live fish, fertilized eggs, and gametes. 93.902 Section 93.902 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN... Animal Species General Provisions for Svc-Regulated Fish Species § 93.902 Ports designated for the...

9 CFR 93.902 - Ports designated for the importation of live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2014 CFR

2014-01-01

... of live fish, fertilized eggs, and gametes. 93.902 Section 93.902 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN... Animal Species General Provisions for Svc-Regulated Fish Species § 93.902 Ports designated for the...

Zebrafish reproduction: revisiting in vitro fertilization to increase sperm cryopreservation success.

PubMed

Hagedorn, Mary; Carter, Virginia L

2011-01-01

Although conventional cryopreservation is a proven method for long-term, safe storage of genetic material, protocols used by the zebrafish community are not standardized and yield inconsistent results, thereby putting the security of many genotypes in individual laboratories and stock centers at risk. An important challenge for a successful zebrafish sperm cryopreservation program is the large variability in the post-thaw in vitro fertilization success (0 to 80%). But how much of this variability was due to the reproductive traits of the in vitro fertilization process, and not due to the cryopreservation process? These experiments only assessed the in vitro process with fresh sperm, but yielded the basic metrics needed for successful in vitro fertilization using cryopreserved sperm, as well. We analyzed the reproductive traits for zebrafish males with a strict body condition range. It did not correlate with sperm volume, or motility (P>0.05), but it did correlate with sperm concentration. Younger males produced more concentrated sperm (P<0.05). To minimize the wastage of sperm during the in vitro fertilization process, 10(6) cells/ml was the minimum sperm concentration needed to achieve an in vitro fertilization success of ≥ 70%. During the in vitro process, pooling sperm did not reduce fertilization success (P>0.05), but pooling eggs reduced it by approximately 30 to 50% (P<0.05). This reduction in fertilization success was due not to the pooling of the females' eggs, but to the type of tools used to handle the eggs. Recommendations to enhance the in vitro process for zebrafish include: 1) using males of a body condition closer to 1.5 for maximal sperm concentration; 2) minimizing sperm wastage by using a working sperm concentration of 10(6) motile cells/ml for in vitro fertilization; and 3) never using metal or sharp-edged tools to handle eggs prior to fertilization.

Zebrafish Reproduction: Revisiting In Vitro Fertilization to Increase Sperm Cryopreservation Success

PubMed Central

Hagedorn, Mary; Carter, Virginia L.

2011-01-01

Although conventional cryopreservation is a proven method for long-term, safe storage of genetic material, protocols used by the zebrafish community are not standardized and yield inconsistent results, thereby putting the security of many genotypes in individual laboratories and stock centers at risk. An important challenge for a successful zebrafish sperm cryopreservation program is the large variability in the post-thaw in vitro fertilization success (0 to 80%). But how much of this variability was due to the reproductive traits of the in vitro fertilization process, and not due to the cryopreservation process? These experiments only assessed the in vitro process with fresh sperm, but yielded the basic metrics needed for successful in vitro fertilization using cryopreserved sperm, as well. We analyzed the reproductive traits for zebrafish males with a strict body condition range. It did not correlate with sperm volume, or motility (P>0.05), but it did correlate with sperm concentration. Younger males produced more concentrated sperm (P<0.05). To minimize the wastage of sperm during the in vitro fertilization process, 106 cells/ml was the minimum sperm concentration needed to achieve an in vitro fertilization success of ≥ 70%. During the in vitro process, pooling sperm did not reduce fertilization success (P>0.05), but pooling eggs reduced it by approximately 30 to 50% (P<0.05). This reduction in fertilization success was due not to the pooling of the females' eggs, but to the type of tools used to handle the eggs. Recommendations to enhance the in vitro process for zebrafish include: 1) using males of a body condition closer to 1.5 for maximal sperm concentration; 2) minimizing sperm wastage by using a working sperm concentration of 106 motile cells/ml for in vitro fertilization; and 3) never using metal or sharp-edged tools to handle eggs prior to fertilization. PMID:21698162

Amphibian fertilization and development in microgravity

NASA Technical Reports Server (NTRS)

Souza, Kenneth A.

1993-01-01

During the year before launch, female frogs will be tested every 3 months for the quantity and quality of eggs produced. Two weeks or more prior to launch, male and female frogs will be transported to the John F. Kennedy Space Center (KSC). During the few weeks before launch, groups will be periodically tested for egg quality to assure that the frogs have adapted to the KSC laboratory environment. About 27 hours before launch, four females will be placed in a damp foam-lined box, called the Adult Frog Box (AFB), through which 100 cc/min of air wil be circulated. The AFB will be lowered into the Spacelab and loaded into the Frog Environmental Unit (FEU) during the final pre-launch preparations. A sperm suspension, for use in flight to fertilize the eggs, will also be prepared and loaded during the pre-launch period. The sperm suspension, together with a kit of syringes containing Human Chorionic Gonadotropin (HCG), will be stored in a refrigerator aboard the shuttle until needed in flight. On the first day of flight, the AFB will be transferred from the FEU to the General Purpose Work Station (GPWS), which is a type of glove box specially designed to allow the crew to use chemicals and biological materials during the flight without contaminating the shuttle/Spacelab environment. Inside the GPWS the four adult frogs will be injected with the HCG hormone and returned to the FEU. Approximately 16 hours after injection, ovulation should have taken place and 15 to 20 eggs from each frog will be placed on each of two egg baskets and covered with sperm for 10 minutes. The egg baskets are inserted into acrylic egg chambers and 50 ml of 'pond water' (20 percent strength Modified Ringers solution (is added. One of the chambers from each frog will be placed on a centrifuge within the FEU and rotated to simulate normal terrestrial gravity (1 g). The remaining chambers are incubated under microgravity conditions within the FEU. Forty minutes after fertilization, the four chambers exposed to 1 g will be removed and observed within the GPWS using a dissecting microscope and camera system. On the basis of egg rotation and egg appearance, the 'best' and 'second best' frogs will be selected to contribute additional eggs. Using the two best frogs, 22 egg chambers will be loaded with eggs and fertilized. Eleven chambers wil be incubated at microgravity and eleven will be incubated on the centrifuge. At various times during the flight, chambers will be removed from the FEU and transferred to the GPWS where a formaldehyde-based fixative will be injected in order to preserve important developmental stages for in depth study following the flight. Five of the 22 chambers plus the eight fertilization test chambers will be returned to Earth with live tadpoles. The swimming behavior of these free swimming tadpoles will be examined within several hours of landing and some will be fixed for a detailed analysis of their inner ear, the otolity, the animals 'balance system.' Lychakov and Vinikov reported an increase in otolith size in tadpoles that developed (but were not fertilized) in space. Live tadpoles from the SL-J flight will be raised through metamorphsis for studies of maturation including an analysis of the effects of space flight on their ability to produce normal progency. Following the flight, the fixed embryos will be serially sectioned and stained using procedures that were developed for this experiment. The embroys fixed at the 2-4 cell stage will be examined for the distribution of cytoplasmic contents, including the various classes of yolk platelets, and the location and shape of the cleavage furrows. The gastrulae will be assessed for the normality of the complex cellular rearrangements that constitute blastopore formation and involution, i.e., the differentiation of the embryo into its specialized body parts. Using a new procedure, the gastrulae will be bleached which will enable the initial sperm entry point (SEP) to be located. The correlation between the SEP and the dorsal lip of the blastopore will be determined. Under normal terrestrial conditions it was shown that the SEP typically is located on the side of the egg opposite the future dorsal side of the embryo. The neurulae will be examined for the normality and completeness of the neural plate and archenteron expansion. The tadpole stages will be used to study the allometry and morphology of the various organ systems.

Repeated Miscarriage

MedlinePlus

... blood and is the body’s main source of fuel. In Vitro Fertilization: A procedure in which an ... that can be done during in vitro fertilization. Tests are performed on the fertilized egg before it ...

The refuge in pheasant management

USGS Publications Warehouse

Dale, F.H.

1951-01-01

1. Cock pheasants in favorable habitats have demonstrated ability to withstand hunting pressures up to 300 gunhours per hundred acres and maintain a satisfactory remnant for breeding purposes. 2. Sex ratios of 10 or more hens per cock are adequate for the production of fertile eggs, and there is evidence that much wider ratios could be tolerated without loss of fertility. 3. Sex ratios divergent enough to reduce egg fertility have not been reported, even in areas of high hunter concentration. 4. Since other pheasant management goals can be attained without protection from hunting, the refuge, per se, must be judged solely on results of a reduced hunting season kill. 5. Even with unusually effective refuges, the reduction in statewide hen kill attributable to refuges is not likely to amount to more than 2 per cent of the hen population. This would be accompanied by a larger reduction in harvest of cocks. 6. Since the usable pheasant population is measured by the harvest, any unnecessary reduction in cock kill must be considered a waste of the game crop and contrary to good management. 7. Legal protection and educational programs designed to save hen pheasants are more selective and probably more effective than refuges in pheasant management. 8. Pheasant populations are products of habitat. Improvement of the entire range within economic limitations and the full utilization of annual population surpluses wherever practicable appear to be reasonable goals of management.

Cryopreservation of common carp (Cyprinus carpio) sperm in 1.2 and 5 ml straws and occurrence of haploids among larvae produced with cryopreserved sperm.

PubMed

Horváth, Akos; Miskolczi, Edit; Mihálffy, Szilvia; Osz, Katalin; Szabó, Krisztián; Urbányi, Béla

2007-06-01

Experiments were carried out on the cryopreservation of common carp (Cyprinus carpio) sperm in order to test the suitability of using 1.2 and 5 ml straws and to investigate the ploidy of malformed larvae found among the hatched progeny. In the first set of experiments, the effect of freezing time was investigated on the hatch rate of embryos. The highest hatch rate for 1.2 ml straws was 69+/-16% at the freezing time of 4 min, and 39+/-27% for 5 ml straws at 5 min. In the second set, the effect different egg volumes fertilized with one straw of sperm on the hatch rate and the rate of malformed larvae was investigated. The highest hatch rate with 1.2 ml straws (86+/-12%) was observed when 10 g of eggs were fertilized with one straw, whereas with 5 ml straws the hatch rate was highest (65+/-18%) when 40 g of eggs were fertilized. The highest rate of malformed larvae (15+/-9%) was found in the control, whereas the highest rate of malformed larvae among the groups fertilized with cryopreserved sperm (13+/-7%) was found in the 1x dose group fertilized with 5 ml straw. The chromosome numbers of malformed larvae were investigated and haploids were found among those hatched from eggs fertilized with cryopreserved sperm whereas only diploids were found in the controls.

Effect of thermal stress on fertility and egg quality of Japanese quail.

PubMed

El-Tarabany, Mahmoud S

2016-10-01

Heat stress is one of the major causes of a decreased performance of laying quail in tropical and subtropical countries. The aim of this study was to investigate the impact of temperature humidity index (THI) on fertility aspects, external and internal egg quality parameters in Japanese quail. One hundred and forty four (144) Japanese quail, 12 of weeks age, were used. Birds were divided randomly into three equal groups, control (at low THI, lower than 70), H 1 (at moderate THI, 70-75) and H 2 (at high THI, 76-80). Quail in the control and H 1 groups had significant greater fertility (p=0.021) and hatchability % (p=0.037), compared with H 2 group. Quail in the control group (at low THI) laid heavier egg weight with a higher external (egg weight (p=0.03), shell thickness, shell weight, eggshell ratio and eggshell density (p=0.001)) and internal egg quality score (albumin weight (p=0.026), yolk height (p=0.003), yolk index (p=0.039) and Haugh unit (p=0.001)). Otherwise, such quality traits were compromised in heat-stressed quail. At the high THI level, egg weight had a significant positive correlation with albumin weight (r=0.58, p<0.01), yolk weight (r=0.22, p<0.05), albumen ratio (r=0.17, p<0.05), yolk height (r=0.14, p<0.05) and yolk index (r=0.18, p<0.05), but was negatively correlated with yolk ratio (r=-0.15, p<0.05). Japanese quail exposed to heat stress (THI over 75) revealed drop in fertility indices and egg quality traits, indicating a detrimental policy of economic income. Copyright © 2016 Elsevier Ltd. All rights reserved.

ELECTRIC IMPEDANCE OF HIPPONOË EGGS

PubMed Central

Cole, Kenneth S.

1935-01-01

Alternating current resistance and capacity measurements have been made from 1.08 103 to 2.32 106 cycles per second on suspensions of unfertilized, fertilized, and swollen unfertilized eggs of the echinoderm Hipponoë esculenta. A simple method has been developed for measuring the volume concentration of eggs in a suspension. The membrane of the unfertilized egg is practically non-conducting at low frequencies and shows a static capacity of 0.87 µf/cm.2 except perhaps at the highest frequencies. The equivalent specific resistance of the egg interior is 11 times that of sea water. The membrane of the fertilized egg is practically non-conducting at low frequencies and shows a static capacity 2.5 times that of the unfertilized egg except at the higher frequencies where another reactive element produces a marked effect. The internal resistance is apparently higher than that of the unfertilized egg. The static capacity per unit area of the membrane decreases as a linear function of the surface area when the eggs are swollen in dilute sea water. In 40 per cent sea water, the capacity falls to about 75 per cent of normal. PMID:19872897

ELECTRIC IMPEDANCE OF ARBACIA EGGS

PubMed Central

Cole, Kenneth S.; Cole, Robert H.

1936-01-01

The alternating current resistance and capacity of suspensions of unfertilized and fertilized eggs of Arbacia punctulata have been measured at frequencies from 103 to 1.64 x 107 cycles per second. The unfertilized egg has a static plasma membrane capacity of 0.73 µf./cm.2 which is practically independent of frequency. The fertilized egg has a static membrane capacity of 3.1 µf./cm.2 at low frequencies which decreases to a value of 0.55 µf./cm.2 at high frequencies. The decrease follows closely the relaxation dispersion of the dielectric constant if the dissipation of such a system is ignored. It is considered more probable that the effect is due to a fertilization membrane of 3.1 µf./cm.2 capacity lifted 1.5 µ. from the plasma membrane, the interspace having the conductivity of sea water. The suspensions show a frequency-dependent capacity at low frequencies which may be attributable to surface conductance. The equivalent low frequency internal specific resistance of both the unfertilized and fertilized egg is about 186 ohm cm. or about 6 times that of sea water, while the high frequency data extrapolate to a value of about 4 times sea water. There is evidence at the highest frequencies that the current is penetrating the nucleus and other materials in the cytoplasm. If this effect were entirely due to the nucleus it would lead to a very approximate value of 0.1 µf./cm.2 for the capacity of the nuclear membrane. The measurements do not indicate any change in this effect on fertilization. PMID:19872952

Response of amphibian egg cytoplasm to novel gravity orientation and centrifugation

NASA Technical Reports Server (NTRS)

Neff, A. W.; Wakahara, M.; Jurand, A.; Malacinski, G. M.

1983-01-01

The effects of inversion and centrifugation on the compartmentalization of cytoplasm in Xenopus laevis eggs are investigated experimentally. The rearrangement of yolk-platelet compartments (YPC) characterized by morphology, density, and viscosity differences is studied in fertilized, unfertilized, and unfertilized electrically activated eggs in normal, and inverted positions and with and without centrifugation at 10-183 x g for 5 min. The eggs are fixed and embedded in plastic or paraffin prior to sagittal sectioning (0.5, 4, or 8 microns) and microscopic examination; the results are presented in a diagram and discussed. A density-compartment model combining both animal/vegetal and dorsal/ventral polarities is proposed: YPC determined without gravity orientation during oogenesis respond to both sperm entrance point and gravity after fertilization, and the response involves breaking of the radial symmetry of the egg. It is predicted that Xenopus eggs in a microgravity environment will encounter difficulties in establishing a primary embryonic axis.

9 CFR 93.905 - Declaration and other documents for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Animal Species General Provisions for Svc-Regulated Fish Species § 93.905 Declaration and other documents... entry, the name and address of the importer, the name and address of the broker, the origin of the live fish, fertilized eggs, or gametes, the number, species, and the purpose of the importation, the name of...

9 CFR 93.905 - Declaration and other documents for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Animal Species General Provisions for Svc-Regulated Fish Species § 93.905 Declaration and other documents... entry, the name and address of the importer, the name and address of the broker, the origin of the live fish, fertilized eggs, or gametes, the number, species, and the purpose of the importation, the name of...

9 CFR 93.905 - Declaration and other documents for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Animal Species General Provisions for Svc-Regulated Fish Species § 93.905 Declaration and other documents... entry, the name and address of the importer, the name and address of the broker, the origin of the live fish, fertilized eggs, or gametes, the number, species, and the purpose of the importation, the name of...

Running out of time: exploring women's motivations for social egg freezing.

PubMed

Baldwin, Kylie; Culley, Lorraine; Hudson, Nicky; Mitchell, Helene

2018-04-12

Few qualitative studies have explored women's use of social egg freezing. Derived from an interview study of 31 participants, this article explores the motivations of women using this technology. Semi-structured interviews were conducted with 31 users of social egg freezing resident in UK (n = 23), USA (n = 7) and Norway (n = 1). Interviews were face to face (n = 16), through Skype and Facetime (n = 9) or by telephone (n = 6). Data were analyzed using interpretive thematic analysis. Women's use of egg freezing was shaped by fears of running out of time to form a conventional family, difficulties in finding a partner and concerns about "panic partnering", together with a desire to avoid future regrets and blame. For some women, use of egg freezing was influenced by recent fertility or health diagnoses as well as critical life events. A fifth of the participants also disclosed an underlying fertility or health issue as affecting their decision. The study provides new insights in to the complex motivations women have for banking eggs. It identifies how women's use of egg freezing was an attempt to "preserve fertility" in the absence of the particular set of "life conditions" they regarded as crucial for pursuing parenthood. It also demonstrates that few women were motivated by a desire to enhance their career and that the boundaries between egg freezing for medical and for social reasons may be more porous than first anticipated.

When Isolated at Full Receptivity, in Vitro Fertilized Wheat (Triticum aestivum, L.) Egg Cells Reveal [Ca2+]cyt Oscillation of Intracellular Origin

PubMed Central

Pónya, Zsolt; Corsi, Ilaria; Hoffmann, Richárd; Kovács, Melinda; Dobosy, Anikó; Kovács, Attila Zoltán; Cresti, Mauro; Barnabás, Beáta

2014-01-01

During in vitro fertilization of wheat (Triticum aestivum, L.) in egg cells isolated at various developmental stages, changes in cytosolic free calcium ([Ca2+]cyt) were observed. The dynamics of [Ca2+]cyt elevation varied, reflecting the difference in the developmental stage of the eggs used. [Ca2+]cyt oscillation was exclusively observed in fertile, mature egg cells fused with the sperm cell. To determine how [Ca2+]cyt oscillation in mature egg cells is generated, egg cells were incubated in thapsigargin, which proved to be a specific inhibitor of the endoplasmic reticulum (ER) Ca2+-ATPase in wheat egg cells. In unfertilized egg cells, the addition of thapsigargin caused an abrupt transient increase in [Ca2+]cyt in the absence of extracellular Ca2+, suggesting that an influx pathway for Ca2+ is activated by thapsigargin. The [Ca2+]cyt oscillation seemed to require the filling of an intracellular calcium store for the onset of which, calcium influx through the plasma membrane appeared essential. This was demonstrated by omitting extracellular calcium from (or adding GdCl3 to) the fusion medium, which prevented [Ca2+]cyt oscillation in mature egg cells fused with the sperm. Combined, these data permit the hypothesis that the first sperm-induced transient increase in [Ca2+]cyt depletes an intracellular Ca2+ store, triggering an increase in plasma membrane Ca2+ permeability, and this enhanced Ca2+ influx results in [Ca2+]cyt oscillation. PMID:25535074

Rare successful pregnancy in a patient with Swyer Syndrome.

PubMed

Taneja, Jyoti; Ogutu, David; Ah-Moye, Michael

2016-10-01

To report a rare successful pregnancy after fertility treatment in a patient with Swyer syndrome. Case report. Herts & Essex Fertility Centre, Cheshunt, UK. A 36-year-old patient with 46, XY gonadal dysgenesis. 31 year old husband with normal sperm analysis. Chromosomal analysis, Saline infusion sonography, Pipelle endometrial scratch, ICSI using donor eggs, Embryo Transfer, and Caesarean delivery. Successful pregnancy and live birth. Successful treatment with donor eggs, pregnancy, and delivery. A patient with 46, XY gonadal dysgenesis in a specially tailored fertility program, can maintain a normal pregnancy and delivery.

Analysis of limited fertility in intracytoplasmic sperm injection of sperm obtained by electroejaculation

PubMed Central

Nakamura, Yoshihiro; Kitamura, Masaya; Nishimura, Kenji; Tsujimura, Akira; Takeyama, Masami; Kondoh, Nobuyuki; Miyazaki, Kazunori; Okuyama, Akihiko

2004-01-01

Background and Aims:  We correlated findings in semen from patients with ejaculatory dysfunction with results of in vitro fertilization using their electroejaculated sperm. Methods and Results:  Electroejaculation was carried out in six patients with the above‐mentioned criteria for a total of eight times. Sperm was obtained in six attempts. Intracytoplasmic injection of these sperm was performed in 156 eggs. Sixty‐seven eggs were fertilized; most of these were injected with motile sperm. Two women became pregnant, both after injection with motile sperm. As previously reported, electroejaculated sperm showed low motility and a low fertilization rate, but even motile sperm had a low fertilization rate. Conclusion:  The results of the present study suggest the importance in fertilization of undetermined factors in addition to sperm motility. (Reprod Med Biol 2004; 3: 9–12) PMID:29662380

Fertility and hatchability in RIR and WL breeds as functionally modified by crossing them in alternate sex combinations (Gallus domesticus).

PubMed

Zelleke, G; Moudgal, R P; Asmare, A

2005-02-01

(1) Four breeding groups of Rhode Island Red and White Leghorn domestic fowl (RIR (female) x RIR (male), RIR (female) x WL (male), WL (female) x RIR (male) and WL (female) x WL (male)) were compared for fertility, hatchability, and their post-insemination sustainability, egg weight loss during incubation and uncovered yolk in abdominal cavity of dead in shell in order to understand the problems associated with the RIR breed in these respects. (2) Crossing RIR (female) with WL (male) or in reverse sex combinations did not improve fertility in comparison to pure RIR chickens and all these groups were less fertile than the pure WL. (3) Unlike fertility, hatchability in RIR improved with the change to either sex partner of the WL breed but the WL (female) x RIR (male) combination was similar to the pure WL (97.72 and 97.12%, respectively). In contrast, crossing RIR (female) with WL (male) resulted in an improvement (86.67%) as compared to pure RIR (76.67%) but still lower than the pure WL and WL (female) x RIR (male) cross. (4) Egg weight loss during incubation was more (20.16%) in pure RIR as compared to RIR (female) x WL (male) (17.13%), followed by WL (female) x RIR (male) (10.28%) and pure WL (9.57%). (5) There were more dead-in-shell embryos with yolks outside their abdominal cavity in pure RIR and their crosses as compared to pure WL breeds. (6) Fertility was sustained for longer in WL than other combinations with post-artificial insemination using constant number of spermatozoa. Fertility after a week of insemination tended to decrease more rapidly than hatchability on a fertile egg basis. (7) It is concluded that both sexes are responsible for the poor fertility in RIR but the female is responsible for poor hatchability and this poor performance is mainly due to greater egg weight loss during incubation.

Parental sex effect of parthenogenesis on hatchability and sperm-egg penetration in mated Chinese Painted quail (Coturnix chinensis).

PubMed

Parker, H M; Ramachandran, R; Nascimento Dos Santos, M; Kawaoku, A J; Wade, C R; Lott, K D; McDaniel, C D

2017-04-01

Selecting quail for an increased incidence of parthenogenesis also impacts egg weight and albumen pH as well as reduces hatchability and fertility due to decreased sperm-egg penetration (SEP). However, it is unknown which parental sex is responsible for these changes in quail selected for parthenogenesis. Therefore, the objective of this study was to determine which sex influences egg weight, albumen pH, hatchability, and SEP in birds selected for parthenogenesis. In this study, 2 lines of birds were used: 1 line that was selected for parthenogenesis and 1 line not selected for parthenogenesis (control). Treatments were as follows: control females w/control males, control females w/parthenogenetic line males, parthenogenetic line females w/control males, and parthenogenetic line females w/parthenogenetic line males. Fresh eggs were collected daily, labeled and analyzed for albumen pH and SEP or incubated at 37.5 °C for 20 d of incubation. Eggs were candled at 10 days of incubation (DOI) and eggs exhibiting little or no embryonic development were removed and broken open to determine hatching failure. This was repeated at 20 DOI for eggs that did not hatch. A dam main effect for egg set weight existed with parthenogenetic line dams exhibiting heavier eggs than control dams. The parthenogenetic line dams and sires exhibited lower albumen pH and hatch but a higher incidence of parthenogenesis than control line dams or sires. However, only a sire main effect existed for fertility and SEP. Sires from the parthenogenetic line yielded the highest infertility due to lower SEP. In conclusion, both the parthenogenetic line dams and sires contribute to reduced reproductive performance. However, it appears that the sire from the parthenogenetic line is responsible for lower fertility due to a reduction in SEP. Because the sire has a negative impact on overall fertility, it is possible that males selected for parthenogenesis have poorer semen quality resulting in fewer sperm traversing the oviduct or penetrating the perivitelline layer. Copyright © 2017 Elsevier Inc. All rights reserved.

CD9 tetraspanin generates fusion competent sites on the egg membrane for mammalian fertilization

PubMed Central

Jégou, Antoine; Ziyyat, Ahmed; Barraud-Lange, Virginie; Perez, Eric; Wolf, Jean Philippe; Pincet, Frédéric; Gourier, Christine

2011-01-01

CD9 tetraspanin is the only egg membrane protein known to be essential for fertilization. To investigate its role, we have measured, on a unique acrosome reacted sperm brought in contact with an egg, the adhesion probability and strength with a sensitivity of a single molecule attachment. Probing the binding events at different locations of wild-type egg we described different modes of interaction. Here, we show that more gamete adhesion events occur on Cd9 null eggs but that the strongest interaction mode disappears. We propose that sperm–egg fusion is a direct consequence of CD9 controlled sperm–egg adhesion properties. CD9 generates adhesion sites responsible for the strongest of the observed gamete interaction. These strong adhesion sites impose, during the whole interaction lifetime, a tight proximity of the gamete membranes, which is a requirement for fusion to take place. The CD9-induced adhesion sites would be the actual location where fusion occurs. PMID:21690351

Genetic evaluation of reproductive potential in the Zatorska goose under a conservation program.

PubMed

Graczyk, Magdalena; Andres, Krzysztof; Kapkowska, Ewa; Szwaczkowski, Tomasz

2018-05-01

The aim of this study was to estimate the genetic parameters and inbreeding effect on the fertility, embryo mortality and hatchability traits in the Zatorska goose covered by the animal genetic resources conservation program. The material for this study contains information about results of hatching of 18 863 eggs from 721 dams and 168 sires, laid between 1998-2015. Genetic parameters were estimated based on the threshold animal model by the use of Restricted Maximum Likelihood and Gibbs sampling. The percentage of fertilized eggs ranged yearly between 37-80%. The percentage of embryo mortality was very low, ranging between 4.63-23.73%. The percentage of the hatched goslings from the total number of analyzed eggs was on average 33.18%, and 53.72% from fertilized eggs. On average based on both methods, the heritability estimates of the fertility, embryo mortality and hatchability reached 0.36, 0.07, 0.24 for males and 0.44, 0.11, 0.32 for females. The genetic trend had increasing tendency for fertility and hatchability and was stable for embryo mortality for both sexes. The obtained result shows that the Zatorska goose can be still maintained in the reserves of the local gene pool according to current rules and use in the local market as a breed with good reproductive potential. © 2018 Japanese Society of Animal Science.

Pregnancy Problems? Boost the Chance of Having a Baby

MedlinePlus

... pregnant, a woman’s body must first release an egg from one of her ovaries, a process called ... then has to join with, or “fertilize,” the egg. The egg must then travel through a passageway ...

Survival of Ascaris eggs and hygienic quality of human excreta in Vietnamese composting latrines.

PubMed

Jensen, Peter K M; Phuc, Pham D; Konradsen, Flemming; Klank, Lise T; Dalsgaard, Anders

2009-12-16

For centuries farmers in Vietnam have fertilized their fields with human excreta collected directly from their household latrines. Contrary to the official guideline of six-month storage, the households usually only store human excreta for three to four months before use, since this is the length of time that farmers have available to produce fertilizer between two cropping seasons. This study aimed to investigate whether hygienically safe fertilizer could be produced in the latrines within this period of time. By inoculating eggs of the helminth parasite indicator Ascaris suum into heaps of human excreta, a die-off experiment was conducted under conditions similar to those commonly used in Vietnamese latrines. Half a ton of human excreta was divided into five heaps containing increasing concentrations of lime from 0% to 11%. Regardless of the starting pH, which varied from 9.4 to 11.6, a >99% die-off of eggs was obtained after 105 to 117 days of storage for all lime concentrations and 97% of eggs were non-viable after 88 days of storage. The most critical parameter found to determine the die-off process was the amount of ammonia (urine) in the excreta which indicates that longer storage periods are needed for parasite egg die-off if urine is separated from the excreta. By inactivating >99% of all A. suum eggs in human excreta during a storage period of only three months the commonly used Double Vault Composting (DVC) latrine, in which urine is not separated, could therefore potentially provide a hygienic acceptable fertilizer.

Activation of maternal centrosomes in unfertilized sea urchin eggs

NASA Technical Reports Server (NTRS)

Schatten, H.; Walter, M.; Biessmann, H.; Schatten, G.

1992-01-01

Centrosomes are undetectable in unfertilized sea urchin eggs, and normally the sperm introduces the cell's microtubule-organizing center (MTOC) at fertilization. However, artificial activation or parthenogenesis triggers microtubule assembly in the unfertilized egg, and this study explores the reappearance and behavior of the maternal centrosome. During activation with A23187 or ammonia, microtubules appear first at the cortex; centrosomal antigen is detected diffusely throughout the entire cytoplasm. Later, the centrosome becomes more distinct and organizes a radial microtubule shell, and eventually a compact centrosome at the egg center organizes a monaster. In these activated eggs, centrosomes undergo cycles of compaction and decompaction in synchrony with the chromatin, which also undergoes cycles of condensation and decondensation. Parthenogenetic activation with heavy water (50% D2O) or the microtubule-stabilizing drug taxol (10 microM) induces numerous centrosomal foci in the unfertilized sea urchin egg. Within 15 min after incubation in D2O, numerous fine centrosomal foci are detected, and they organize a connected network of numerous asters which fill the entire egg. Taxol induces over 100 centrosomal foci by 15 min after treatment, which organize a corresponding number of asters. The centrosomal material in either D2O- or taxol-treated eggs aggregates with time to form fewer but denser foci, resulting in fewer and larger asters. Fertilization of eggs pretreated with either D2O or taxol shows that the paternal centrosome is dominant over the maternal centrosome. The centrosomal material gradually becomes associated with the enlarged sperm aster. These experiments demonstrate that maternal centrosomal material is present in the unfertilized egg, likely as dispersed undetectable material, which can be activated without paternal contributions. At fertilization, paternal centrosomes become dominant over the maternal centrosomal material.

Fertilization Induces a Transient Exposure of Phosphatidylserine in Mouse Eggs

PubMed Central

Curia, Claudio A.; Ernesto, Juan I.; Stein, Paula; Busso, Dolores; Schultz, Richard M.; Cuasnicu, Patricia S.; Cohen, Débora J.

2013-01-01

Phosphatidylserine (PS) is normally localized to the inner leaflet of the plasma membrane and the requirement of PS translocation to the outer leaflet in cellular processes other than apoptosis has been demonstrated recently. In this work we investigated the occurrence of PS mobilization in mouse eggs, which express flippase Atp8a1 and scramblases Plscr1 and 3, as determined by RT-PCR; these enzyme are responsible for PS distribution in cell membranes. We find a dramatic increase in binding of flouresceinated-Annexin-V, which specifically binds to PS, following fertilization or parthenogenetic activation induced by SrCl2 treatment. This increase was not observed when eggs were first treated with BAPTA-AM, indicating that an increase in intracellular Ca2+ concentration was required for PS exposure. Fluorescence was observed over the entire egg surface with the exception of the regions overlying the meiotic spindle and sperm entry site. PS exposure was also observed in activated eggs obtained from CaMKIIγ null females, which are unable to exit metaphase II arrest despite displaying Ca2+ spikes. In contrast, PS exposure was not observed in TPEN-activated eggs, which exit metaphase II arrest in the absence of Ca2+ release. PS exposure was also observed when eggs were activated with ethanol but not with a Ca2+ ionophore, suggesting that the Ca2+ source and concentration are relevant for PS exposure. Last, treatment with cytochalasin D, which disrupts microfilaments, or jasplakinolide, which stabilizes microfilaments, prior to egg activation showed that PS externalization is an actin-dependent process. Thus, the Ca2+ rise during egg activation results in a transient exposure of PS in fertilized eggs that is not associated with apoptosis. PMID:23951277

Effects of toxic compounds in Montipora capitata on exogenous and endogenous zooxanthellae performance and fertilization success.

PubMed

Hagedorn, Mary; Farrell, Ann; Carter, Virginia; Zuchowicz, Nikolas; Johnston, Erika; Padilla-Gamiño, Jacqueline; Gunasekera, Sarath; Paul, Valerie

2015-01-01

Studies have identified chemicals within the stony coral genus Montipora that have significant biological activities. For example, Montiporic acids A and B and other compounds have been isolated from the adult tissue and eggs of Montipora spp. and have displayed antimicrobial activity and cytotoxicity in cultured cells. The ecological role of these toxic compounds is currently unclear. This study examines the role these toxins play in reproduction. Toxins were found in the eggs and larvae of the coral Montipora capitata. Releasing these toxins by crushing both the eggs and larvae resulted in irreversible inhibition of photosynthesis in endogenous and exogenous zooxanthellae within minutes. Moreover, these toxins were stable, as frozen storage of eggs and larvae did not affect toxicity. Photosynthetic competency of Porites compressa zooxanthellae treated with either frozen or fresh, crushed eggs was inhibited similarly (P > 0.05, ANCOVA). Addition of toxic eggs plugs to live P. compressa fragments caused complete tissue necrosis under the exposed area on the fragments within 1 week. Small volumes of M. capitata crushed eggs added to sperm suspensions reduced in vitro fertilization success by killing the sperm. After 30 min, untreated sperm maintained 90 ± 1.9% SEM motility while those treated with crushed eggs were rendered immotile, 4 ± 1.4% SEM. Flow cytometry indicated membrane disruption of the immotile sperm. Fertilization success using untreated sperm was 79 ± 4% SEM, whereas the success rate dropped significantly after exposure to the crushed eggs, 1.3 ± 0% SEM. Unlike the eggs and the larvae, M. capitata sperm did not reduce the photosynthetic competency of P. compressa zooxanthellae, suggesting the sperm was nontoxic. The identity of the toxins, cellular mechanism of action, advantage of the toxins for M. capitata and their role on the reef are still unknown.

Effect of external cryoprotectants as membrane stabilizers on cryopreserved rainbow trout sperm.

PubMed

Cabrita, E; Anel, L; Herraéz, M P

2001-09-01

The process of freezing and thawing induces certain cellular damage in rainbow trout (Oncorhynchus mykiss) spermatozoa. We have previously demonstrated that after freezing and thawing decreased fertility in rainbow trout (Oncorhynchus mykiss) spermatozoa, is related to sublethal damage to the plasma membrane. External cryoprotectants are known to stabilize the sperm cell membrane against such damage. In the current study, we used a basic freezing extender containing #6 Erdahl and Graham and 7% DMSO and added egg yolk, BSA, and a soybean-protein complex (DanPro S760) singly and in various combinations. To assess the effect of these cryoprotectants we evaluated the percentage of cells with progressive motility, permeability of cells to propidium iodide (viability) after exposure for 30 sec, 2, 5, 10 and 15 min. to hypo- and isoosmotic solutions of 10 and 300 mOsm, and the in vitro fertility rate. Fertility trials were performed using 1.87 x 10(7) spermatozoa/egg. Some of the tested stabilizers increased motility, increased viability, or reduced cell fragility after freezing and thawing. Nevertheless these quality improvements demonstrated by the "in vitro" tests do not always correlate with high fertility. The best membrane protection in terms of resistance to hypoosmotic shock was achieved when BSA and egg yolk were added to the extender. The highest fertility rates were obtained with DanPro S760 alone or in combination with BSA; the use of BSA with egg yolk did not improve this parameter. Our results demonstrated that some external cryoprotectants effectively increased membrane resistance during freezing and thawing, but some of the tested mixtures interfered with fertilization. Soybean protein concentrate provided good protection and increased fertility rates in cryopreserved trout spermatozoa.

Sexual selection for genetic compatibility: the role of the major histocompatibility complex on cryptic female choice in Chinook salmon (Oncorhynchus tshawytscha).

PubMed

Gessner, C; Nakagawa, S; Zavodna, M; Gemmell, N J

2017-05-01

Cryptic female choice (CFC), a form of sexual selection during or post mating, describes processes of differential sperm utilization by females to bias fertilization outcomes towards certain males. In Chinook salmon (Oncorhynchus tshawytscha) the ovarian fluid surrounding the ova of a given female differently enhances the sperm velocity of males. Sperm velocity is a key ejaculate trait that determines fertilization success in externally fertilizing fishes, thus the differential effect on sperm velocity might bias male fertilization outcomes and represent a mechanism of CFC. Once sperm reach the oocyte, CFC could potentially be further facilitated by sperm-egg interactions, which are well understood in externally fertilizing marine invertebrates. Here, we explored the potential genetic basis of both possible mechanisms of CFC by examining whether the genotypic combinations of mates (amino-acid divergence, number of shared alleles) at the major histocompatibility complex (MHC) class I and II explain the variation in sperm velocity and/or male fertilization success that is not explained by sperm velocity, which might indicate MHC-based sperm-egg interactions. We recorded sperm velocity in ovarian fluid, employed paired-male fertilization trials and evaluated the fertilization success of each male using microsatellite-based paternity assignment. We showed that relative sperm velocity was positively correlated with fertilization success, confirming that the differential effect on sperm velocity may be a mechanism of CFC in Chinook salmon. The variation in sperm velocity was independent of MHC class I and II. However, the MHC class II divergence of mates explained fertilization success, indicating that this locus might influence sperm-egg interactions.

Development of methods for cryopreservation of rooster sperm from the endangered breed "Gallina Valenciana de Chulilla" using low glycerol concentrations.

PubMed

Blanch, E; Tomás, C; Casares, L; Gómez, E A; Sansano, S; Giménez, I; Mocé, E

2014-06-01

Glycerol (11%; v:v) is the cryoprotectant most often used for the cryopreservation of rooster sperm. However, chicken breeds differ in the resistance of their sperm to the cryopreservation process and endangered or local breeds usually present low fertilizing ability when conventional sperm cryopreservation protocols are used. The objective of this study was to optimize the protocol for the cryopreservation of the sperm from the endangered breed "Gallina Valenciana de Chulilla". For this purpose, 10 pools of semen from 43 roosters of this breed were cryopreserved using 8%, 7%, 6%, or 4% glycerol, and the sperm quality was determined immediately after thawing and in the insemination doses. Lohmann Brown Classic laying hens (n = 40) were used for the insemination trials. The sperm quality after cryopreservation progressively decreased as the glycerol concentration was reduced (P < 0.01); samples frozen using 4% glycerol exhibited the lowest quality (38% total motile sperm and 49% live sperm), and samples frozen using 8% glycerol exhibited the highest quality (67% total motile sperm and 66% live sperm). These differences were also observed after the glycerol was removed (P < 0.01). However, the sperm fertilizing ability was similar for all the treatments (23%-30% fertilized eggs), and increased as the glycerol concentration decreased. In conclusion, semen from roosters frozen using 4% glycerol exhibited lower sperm quality but similar fertilizing ability compared with samples processed using higher glycerol concentrations. These results may provide useful information for developing cryopreservation protocols for other breeds. Copyright © 2014 Elsevier Inc. All rights reserved.

Delineating the roles of males and females in sperm competition

PubMed Central

Evans, Jonathan P.; Rosengrave, Patrice; Gasparini, Clelia; Gemmell, Neil J.

2013-01-01

Disentangling the relative roles of males, females and their interactive effects on competitive fertilization success remains a challenge in sperm competition. In this study, we apply a novel experimental framework to an ideally suited externally fertilizing model system in order to delineate these roles. We focus on the chinook salmon, Oncorhynchus tshawytscha, a species in which ovarian fluid (OF) has been implicated as a potential arbiter of cryptic female choice for genetically compatible mates. We evaluated this predicted sexually selected function of OF using a series of factorial competitive fertilization trials. Our design involved a series of 10 factorial crosses, each involving two ‘focal’ rival males whose sperm competed against those from a single ‘standardized’ (non-focal) rival for a genetically uniform set of eggs in the presence of OF from two focal females. This design enabled us to attribute variation in competitive fertilization success among focal males, females (OF) and their interacting effects, while controlling for variation attributable to differences in the sperm competitive ability of rival males, and male-by-female genotypic interactions. Using this experimental framework, we found that variation in sperm competitiveness could be attributed exclusively to differences in the sperm competitive ability of focal males, a conclusion supported by subsequent analyses revealing that variation in sperm swimming velocity predicts paternity success. Together, these findings provide evidence that variation in paternity success can be attributed to intrinsic differences in the sperm competitive ability of rival males, and reveal that sperm swimming velocity is a key target of sexual selection. PMID:24266039

Neutral and selection-driven decay of sexual traits in asexual stick insects

PubMed Central

Schwander, Tanja; Crespi, Bernard J.; Gries, Regine; Gries, Gerhard

2013-01-01

Environmental shifts and lifestyle changes may result in formerly adaptive traits becoming non-functional or maladaptive. The subsequent decay of such traits highlights the importance of natural selection for adaptations, yet its causes have rarely been investigated. To study the fate of formerly adaptive traits after lifestyle changes, we evaluated sexual traits in five independently derived asexual lineages, including traits that are specific to males and therefore not exposed to selection. At least four of the asexual lineages retained the capacity to produce males that display normal courtship behaviours and are able to fertilize eggs of females from related sexual species. The maintenance of male traits may stem from pleiotropy, or from these traits only regressing via drift, which may require millions of years to generate phenotypic effects. By contrast, we found parallel decay of sexual traits in females. Asexual females produced altered airborne and contact signals, had modified sperm storage organs, and lost the ability to fertilize their eggs, impeding reversals to sexual reproduction. Female sexual traits were decayed even in recently derived asexuals, suggesting that trait changes following the evolution of asexuality, when they occur, proceed rapidly and are driven by selective processes rather than drift. PMID:23782880

Potency of blue catfish, Ictalurus furcatus (individual vs pooled) sperm to fertilize stripped channel catfish, I. punctatus eggs on the production and performance of progeny

USDA-ARS?s Scientific Manuscript database

Channel x blue hybrid catfish is the desired genotype for US farm-raised catfish industry. Induced spawning of gravid channel catfish, followed by fertilization of stripped eggs with blue catfish sperm is the only reliable means to produce hybrid catfish embryos in hatcheries. Hybrid catfish fry p...

Ectopic pregnancy

MedlinePlus

Tubal pregnancy; Cervical pregnancy; Tubal ligation - ectopic pregnancy ... In most pregnancies, the fertilized egg travels through the fallopian tube to the womb (uterus). If the movement of the egg ...

Selection for Duration of Fertility and Mule Duck White Plumage Colour in a Synthetic Strain of Ducks (Anas platyrhynchos).

PubMed

Liu, H C; Huang, J F; Lee, S R; Liu, H L; Hsieh, C H; Huang, C W; Huang, M C; Tai, C; Poivey, J P; Rouvier, R; Cheng, Y S

2015-05-01

A synthetic strain of ducks (Anas platyrhynchos) was developed by introducing genes for long duration of fertility to be used as mother of mule ducklings and a seven-generation selection experiment was conducted to increase the number of fertile eggs after a single artificial insemination (AI) with pooled Muscovy semen. Reciprocal crossbreeding between Brown Tsaiya LRI-2 (with long duration of fertility) and Pekin L-201 (with white plumage mule ducklings) ducks produced the G0. Then G1 were intercrossed to produce G2 and so on for the following generations. Each female duck was inseminated 3 times, at 26, 29, and 32 weeks of age. The eggs were collected for 14 days from day 2 after AI. Individual data regarding the number of incubated eggs (Ie), the number of fertile eggs at candling at day 7 of incubation (F), the total number of dead embryos (M), the maximum duration of fertility (Dm) and the number of hatched mule ducklings (H) with plumage colour were recorded. The selection criterion was the breeding values of the best linear unbiased prediction animal model for F. The results show high percentage of exhibited heterosis in G2 for traits to improve (19.1% for F and 12.9% for H); F with a value of 5.92 (vs 3.74 in the Pekin L-201) was improved in the G2. Heritabilities were found to be low for Ie (h (2) = 0.07±0.03) and M (h (2) = 0.07±0.01), moderately low for Dm (h (2) = 0.13±0.02), of medium values for H (h (2) = 0.20±0.03) and F (h (2) = 0.23±0.03). High and favourable genetic correlations existed between F and Dm (rg = 0.93), between F and H (rg = 0.97) and between Dm and H (rg = 0.90). The selection experiment showed a positive trend for phenotypic values of F (6.38 fertile eggs in G10 of synthetic strain vs 5.59 eggs in G4, and 3.74 eggs in Pekin L-201), with correlated response for increasing H (5.73 ducklings in G10 vs 4.86 in G4, and 3.09 ducklings in Pekin L-201) and maximum duration of the fertile period without increasing the embryo mortality rate. The average predicted genetic response for F was 40% of genetic standard deviation per generation of selection. The mule ducklings' feather colour also was improved. It was concluded that this study provided results for a better understanding of the genetics of the duration of fertility traits in the common female duck bred for mule and that the selection of a synthetic strain was effective method of improvement.

Calcium at fertilization and in early development

PubMed Central

Whitaker, Michael

2012-01-01

Fertilization calcium waves are introduced and the evidence from which we can infer general mechanisms of these waves is presented. The two main classes of hypothesis put forward to explain the generation of the fertilization calcium wave are set out and it is concluded that initiation of the fertilization calcium wave can be most generally explained in inverterbrates by a mechanism in which an activating substance enters the egg from the sperm on sperm-egg fusion, activating the egg by stimulating phospholipase C activation through a src family kinase pathway and in mammals by the diffusion of a sperm-specific phospholipase C from sperm to egg on sperm-egg fusion. The fertilization calcium wave is then set into the context of cell cycle control and the mechanism of repetitive calcium spiking in mammalian eggs is investigated. Evidence that calcium signals control cell division in early embryos is reviewed, and it is concluded that calcium signals are essential at all three stages of cell division in early embryos. Evidence that phosphoinositide signalling pathways control the resumption of meiosis during oocyte maturation is considered. It is concluded on balance that the evidence points to a need for phosphoinositide/calcium signalling during resumption of meiosis. Changes to the calcium signalling machinery occur during meiosis to enable the production of a calcium wave in the mature oocyte when it is fertilized; evidence that the shape and structure of the endoplasmic reticulum alters dynamically during maturation and after fertilization is reviewed and the link between ER dynamics and the cytoskeleton is discussed. There is evidence that calcium signalling plays a key part in the development of patterning in early embryos. Morphogenesis in ascidian, frog and zebrafish embryos is briefly described to provide the developmental context in which calcium signals act. Intracellular calcium waves that may play a role in axis formation in ascidian are discussed. Evidence that the Wingless/calcium signalling pathway is a strong ventralizing signal in Xenopus, mediated by phoshoinositide signalling is adumbrated. The central role that calcium channels play in morphogenetic movements during gastrulation and in ectodermal and mesodermal gene expression during late gastrulation is demonstrated. Experiments in zebrafish provide a strong indication that calcium signals are essential for pattern formation and organogenesis. PMID:16371595

The Control of Male Fertility by Spermatozoan Ion Channels

PubMed Central

Lishko, Polina V.; Kirichok, Yuriy; Ren, Dejian; Navarro, Betsy; Chung, Jean-Ju

2014-01-01

Ion channels control the sperm ability to fertilize the egg by regulating sperm maturation in the female reproductive tract and by triggering key sperm physiological responses required for successful fertilization such as hyperactivated motility, chemotaxis, and the acrosome reaction. CatSper, a pH-regulated, calcium-selective ion channel, and KSper (Slo3) are core regulators of sperm tail calcium entry and sperm hyperactivated motility. Many other channels had been proposed as regulating sperm activity without direct measurements. With the development of the sperm patch-clamp technique, CatSper and KSper have been confirmed as the primary spermatozoan ion channels. In addition, the voltage-gated proton channel Hv1 has been identified in human sperm tail, and the P2X2 ion channel has been identified in the midpiece of mouse sperm. Mutations and deletions in sperm-specific ion channels affect male fertility in both mice and humans without affecting other physiological functions. The uniqueness of sperm ion channels makes them ideal pharmaceutical targets for contraception. In this review we discuss how ion channels regulate sperm physiology. PMID:22017176

Generation of eggs from mouse embryonic stem cells and induced pluripotent stem cells.

PubMed

Hayashi, Katsuhiko; Saitou, Mitinori

2013-08-01

Oogenesis is an integrated process through which an egg acquires the potential for totipotency, a fundamental condition for creating new individuals. Reconstitution of oogenesis in a culture that generates eggs with proper function from pluripotent stem cells (PSCs) is therefore one of the key goals in basic biology as well as in reproductive medicine. Here we describe a stepwise protocol for the generation of eggs from mouse PSCs, such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). ESCs and iPSCs are first induced into primordial germ cell-like cells (PGCLCs) that are in turn aggregated with somatic cells of female embryonic gonads, the precursors for adult ovaries. Induction of PGCLCs followed by aggregation with the somatic cells takes up to 8 d. The aggregations are then transplanted under the ovarian bursa, in which PGCLCs grow into germinal vesicle (GV) oocytes in ∼1 month. The PGCLC-derived GV oocytes can be matured into eggs in 1 d by in vitro maturation (IVM), and they can be fertilized with spermatozoa by in vitro fertilization (IVF) to obtain healthy and fertile offspring. This method provides an initial step toward reconstitution of the entire process of oogenesis in vitro.

Predicted time from fertilization to maximum wet weight for steelhead alevins based on incubation temperature and egg size (Study site: Western Fishery Research Center, Seattle; Stock: Dworshak hatchery; Year class: 1996): Chapter 4

USGS Publications Warehouse

Rubin, Stephen P.; Reisenbichler, Reginald R.; Slatton, Stacey L.; Rubin, Stephen P.; Reisenbichler, Reginald R.; Wetzel, Lisa A.; Hayes, Michael C.

2012-01-01

The accuracy of a model that predicts time between fertilization and maximum alevin wet weight (MAWW) from incubation temperature was tested for steelhead Oncorhynchus mykiss from Dworshak National Fish Hatchery on the Clearwater River, Idaho. MAWW corresponds to the button-up fry stage of development. Embryos were incubated at warm (mean=11.6°C) or cold (mean=7.3°C) temperatures and time between fertilization and MAWW was measured for each temperature. Model predictions of time to MAWW were within 1% of measured time to MAWW. Mean egg weight ranged from 0.101-0.136 g among females (mean = 0.116). Time to MAWW was positively related to egg size for each temperature, but the increase in time to MAWW with increasing egg size was greater for embryos reared at the warm than at the cold temperature. We developed equations accounting for the effect of egg size on time to MAWW for each temperature, and also for the mean of those temperatures (9.3°C).

Possible natural hybridization of two morphologically distinct species of Acropora (Cnidaria, Scleractinia) in the Pacific: fertilization and larval survival rates.

PubMed

Isomura, Naoko; Iwao, Kenji; Fukami, Hironobu

2013-01-01

Natural hybridization of corals in the Indo-Pacific has been considered rather rare. However, field studies have observed many corals with intermediate interspecific or unusual morphologies. Given that the existence of F1 hybrids with intermediate interspecific morphologies has been proven in the Caribbean, hybrids may also inhabit the Indo-Pacific and occur more frequently than expected. In this study, we focused on two morphologically different species, Acropora florida and A. intermedia, and performed crossing experiments at Akajima Island, Japan. Results showed that these species could hybridize in both directions via eggs and sperm, but that fertilization rates significantly differed according to which species provided eggs. These results are similar to those reported from the Caribbean. Although all embryos developed normally to the planular larval stage, the developmental processes of some hybrid embryos were delayed by approximately 1 h compared with conspecific embryos, suggesting that fertilization occurred 1 h later in interspecific crosses than in intraspecific crosses. More successful hybridization could occur under conditions with low numbers of conspecific colonies. Additionally, a comparison of survival rates between hybrid and intraspecific larvae revealed that intra- and interspecific larvae produced from eggs of A. florida survived for significantly longer than those produced from eggs of A. intermedia. Considering these data, under specific conditions, hybrids can be expected to be produced and survive in nature in the Pacific. Furthermore, we identified one colony with intermediate morphology between A. florida and A. intermedia in the field. This colony was fertilized only by eggs of A. florida, with high fertilization rates, suggesting that this colony would be a hybrid of these two species and might be backcrossed.

The influence of clinostat rotation on the fertilized amphibian egg.

NASA Technical Reports Server (NTRS)

Tremor, J. W.; Souza, K. A.

1972-01-01

Study in which unrestrained, fertilized eggs of Rana pipiens and Xenopus laevis were rotated in a plane parallel to the normal gravity vector. In R. pipiens rotation at 1/4 rpm for five days at 18 C produced a significantly increased number of commonly occurring abnormalities. Rotation at 1/15, 1/8, 1, 2, 5 and 10 rpm did not significantly affect normal development. X. laevis eggs reacted similarly. R. pipiens eggs were most sensitive to rotation at 1/4 rpm when exposure was initiated before first cleavage. Mixing of intracellular constituents apparently occurred only at 1/4 rpm in R. pipiens (of the clinostat speeds studied), and may have been the cause of the increased abnormality observed at this rate.

Chemical Communication and Reproduction Partitioning in Social Wasps.

PubMed

Dani, Francesca Romana; Turillazzi, Stefano

2018-05-22

Social wasps encompass species displaying diverse social organization regarding colony cycle, nest foundation, caste differences (from none to significant dimorphism) and number of reproductive queens. Current phylogenetic data suggests that sociality occured independently in the subfamily Stenogastrinae and in the Polistinae+Vespinae clade. In most species, including those with the simplest social organization, colony reproduction is monopolised by a single or few females. Since their nest mates can also develop ovaries and lay eggs, dominant females must somehow inhibit them from reproducing. Physical interactions in the form of open aggression or, usually, ritualised dominance by the fertile females contribute to fertility inhibition in several species, but it is unlikely to function in large colonies. In the latter case, reproduction within the colony is likely to be regulated through pheromones. Relatively little is known about these semiochemicals. Studies on all the three social wasp subfamilies, revealed that cuticular hydrocarbon components differ in abundance between egg-laying and not egg-laying females and that their composition depends on fertility status. In several species, females have been reported to manifestly react towards females with activated ovaries, but there is little evidence to support the hypothesis that fertile individuals are either recognized through their CHC composition, or that over-represented CHC constituents can inhibit fertility. Moreover, very little information exists on the possibility that exocrine glands release fertility signals or chemicals inhibiting fertility.

Effects of preincubation of eggs and activation medium on the percentage of eyed embryos in ide (Leuciscus idus), an externally fertilizing fish.

PubMed

Siddique, Mohammad Abdul Momin; Linhart, Otomar; Krejszeff, Sławomir; Żarski, Daniel; Król, Jarosław; Butts, Ian Anthony Ernest

2016-03-15

Standardization of fertilization protocols is crucial for improving reproductive techniques for externally fertilizing fish in captive breeding. Therefore, the objectives of this study were to determine the effects of preincubation of eggs and activation medium on the percentage of eyed embryos for ide (Leuciscus idus). Pooled eggs from five females were preincubated in three different activating media for 0, 30, 60, 90, and 120 seconds and then fertilized by pooled sperm from five males. At the eyed-egg stage, the percentage of viable embryos was later calculated. Results showed that preincubation time was significant for the freshwater activation medium (P < 0.001), such that the percentage of eyed embryos declined across the preincubation time gradient. Additionally, there was an effect on the percentage of eyed embryos when eggs were incubated with Woynarovich solution (P < 0.001), such that a decline was detected at 90 seconds, whereas no effect was detected for the saline water medium. Activating medium had a significant effect on the percentage of eyed embryos for each preincubation time (P < 0.05). More precisely, freshwater produced the lowest percentage of eyed embryos at all preincubation times (ranged from 1.9% at 120 seconds to 43.6% at 0 seconds), whereas saline water and Woynarovich solution produced the highest percentage of eyed embryos at 0 seconds and 30 seconds before incubation. Woynarovich solution produced the highest percentage of eyed embryos at 60 seconds (65.26%), whereas saline water produced the highest percentage at 90 seconds (68.37%). No difference was detected between saline water and Woynarovich solution at 120 seconds. Examination of sperm traits showed no impact of activating medium on computer assisted sperm analysis parameters. Together, these results suggest that saline water or Woynarovich solution improve fertilization rate in ide during IVF; thus, these media are useful for standardizing fertilization protocols and controlled reproduction for this species. Copyright © 2016 Elsevier Inc. All rights reserved.

Auxin production couples endosperm development to fertilization.

PubMed

Figueiredo, Duarte D; Batista, Rita A; Roszak, Pawel J; Köhler, Claudia

2015-11-23

In flowering plants, seed development is preceded by a double fertilization event, whereby two male sperm cells fuse with two female gametes: the egg and central cells. The fertilized egg cell will form the embryo, and the fertilized central cell will give rise to the triploid endosperm, whose function is to nourish and support the embryo. Even though the endosperm has an unparalleled role for human nutrition, the molecular bases for its development are yet to be understood. Our results reveal that increasing auxin levels after fertilization drive the replication of the central cell in Arabidopsis thaliana. Auxin is sufficient to trigger central cell division and is necessary for correct endosperm development, a process dependent on the MADS-box transcription factor AGL62 (AGAMOUS-LIKE 62). We propose that the epigenetic regulators of the Polycomb group (PcG) family block central cell division before fertilization by repressing the expression of auxin biosynthesis genes in the female gametophyte.

Effects of triploidy induction on physiological and immunological characteristics of rainbow trout (Oncorhynchus mykiss) at early developmental stages (fertilized eggs, eyed eggs and fry).

PubMed

Salimian, Shekoofeh; Keyvanshokooh, Saeed; Salati, Amir Parviz; Pasha-Zanoosi, Hossein; Babaheydari, Samad Bahrami

2016-02-01

The aim of this study was to compare effects of triploidy induction on basal physiological and immunological characteristics in rainbow trout at three developmental stages including fertilized eggs, eyed eggs and fry. Eggs and milt were taken from eight females and six males. The gametes were pooled to minimize the individual differences. After insemination, the eggs were incubated at 10°C for 10min. Half of the fertilized eggs were then subjected to heat shock for 10min submerged in a 28°C water bath to induce triploidy. The remainder were incubated normally and used as diploid controls. Three batches of eggs were randomly selected from each group and were incubated at 10-11°C under the same environmental conditions in hatchery troughs until the fry stage. The first-feeding offspring were also reared under the same environmental and nutritional conditions for 38 days. Triplicate samples of 30 eggs (10 eggs per trough) from each group were selected 1.5h post-fertilization and at the eyed stage. Based on red blood cell analysis, nine diploid and nine triploid fish were also selected for study. The triploidy induction success rate was 87.1%. While diploid fish had greater body weights than those in the heat-shock treatment group, weight gain (WG%) was not different between the fry of the diploid and heat-shock treatment groups. Of thyroid hormones measured, 3,5,3'-triiodo-l-thyronine (T3) was less (P<0.05) in eyed eggs of the heat-shock treatment group, but thyroxine (T4) was greater in fry of the heat-shock treatment group as compared to those that were diploid. Cortisol concentration was greater in fry of the heat-shock treatment group as compared to those that were diploid suggesting that fry in the triploid state may be more susceptible to stressors. Concentrations of immune variables (lysozyme, ACH50, albumin, IgM, total protein, globulin and complement) were either comparable or greater in fry of the heat-shock treatment group suggesting that the immune system is not impaired in fish as a result of triploidy induction. Copyright © 2015 Elsevier B.V. All rights reserved.

Centrosome structure and function is altered by chloral hydrate and diazepam during the first reproductive cell cycles in sea urchin eggs

NASA Technical Reports Server (NTRS)

Schatten, H.; Chakrabarti, A.

1998-01-01

This paper explores the mode of action of the tranquillizers chloral hydrate and diazepam during fertilization and mitosis of the first reproductive cell cycles in sea urchin eggs. Most striking effects of these drugs are the alteration of centrosomal material and the abnormal microtubule configurations during exposure and after recovery from the drugs. This finding is utilized to study the mechanisms of centrosome compaction and decompaction and the dynamic configurational changes of centrosomal material and its interactions with microtubules. When 0.1% chloral hydrate or 350-750 microM diazepam is applied at specific phases during the first cell cycle of sea urchin eggs, expanded centrosomal material compacts at distinct regions and super-compacts into dense spheres while microtubules disassemble. When eggs are treated before pronuclear fusion, centrosomal material aggregates around each of the two pronuclei while microtubules disappear. Upon recovery, atypical asters oftentimes with multiple foci are formed from centrosomal material surrounding the pronuclei which indicates that the drugs have affected centrosomal material and prevent it from functioning normally. Electron microscopy and immunofluorescence studies with antibodies that routinely stain centrosomes in sea urchin eggs (4D2; and Ah-6) depict centrosomal material that is altered when compared to control cells. This centrosomal material is not able to reform normal microtubule patterns upon recovery but will form multiple asters around the two pronuclei. When cells are treated with 0.1% chloral hydrate or 350-750 microM diazepam during mitosis, the bipolar centrosomal material becomes compacted and aggregates into multiple dense spheres while spindle and polar microtubules disassemble. With increased incubation time, the smaller dense centrosome particles aggregate into bigger and fewer spheres. Upon recovery, unusual irregular microtubule configurations are formed from centrosomes that have lost their ability to reform normal mitotic figures. These results indicate that chloral hydrate and diazepam affect centrosome structure which results in the inability to reform normal microtubule formations and causes abnormal fertilization and mitosis.

Hatching success of ostrich eggs in relation to setting, turning and angle of rotation.

PubMed

van Schalkwyk, S J; Cloete, S W; Brown, C R; Brand, Z

2000-03-01

1. Three trials were designed to study the effects of axis of setting, turning frequency and axis and angle of rotation on the hatching success of ostrich eggs. The joint effects of axis of setting and angle of rotation were investigated in a fourth trial. 2. The hatchability of fertile ostrich eggs artificially incubated in electronic incubators (turned through 60 degrees hourly) was improved substantially in eggs set in horizontal positions for 2 or 3 weeks and vertically for the rest of the time. 3. The hatchability of fertile eggs set in the horizontal position without any turning was very low (27%). It was improved to approximately 60% by manual turning through 180 degrees around the short axis and through 60 degrees around the long axis at 08.00 and 16.00 h. A further improvement to approximately 80% was obtained in eggs automatically turned through 60 degrees around the long axis in the incubator. Additional turning through 180 degrees around the short axis twice daily at 08.00 and 16.00 h resulted in no further improvement. 4. The hatchability of fertile eggs set vertically in electronic incubators and rotated hourly through angles ranging from 60 degrees to 90 degrees around the short axis increased linearly over the range studied. The response amounted to 1.83% for an increase of 10 (R2=0.96). 5. The detrimental effect of rotation through the smaller angle of 60 degrees around the short axis could be compensated for by setting ostrich eggs in the horizontal position for 2 weeks before putting them in the vertical position.

Effects of Schistosoma haematobium infection on reproductive success and male outcrossing ability in the simultaneous hermaphrodite, Bulinus truncatus (Gastropoda: Planorbidae).

PubMed

Schrag, S J; Rollinson, D

1994-01-01

The schistosome intermediate snail host, Bulinus truncatus (Mollusca: Planorbidae), has two reproductive (phally) morphs. Both aphallics and euphallics can self-fertilize, but aphallics cannot donate sperm because they do not develop a functional penis and prostate. This study investigated the interactions between phally and fitness consequences of Schistosoma haematobium infection in B. truncatus. Snails which developed patent infections produced 26% fewer eggs than controls and 35% fewer eggs than exposed snails which did not develop infections. This reduction was due to a lower lifetime production of egg masses and a smaller mean number of eggs/mass in infected snails relative to control or exposed snails. However, there was no evidence of increased mortality in infected snails. Contrary to reports of fecundity compensation in other intermediate host snails, egg production post-exposure during the pre-patent period did not increase relative to that of controls in either infected or exposed snails. Phally did not influence susceptibility to infection or length of the prepatent period. Furthermore, lifetime egg, egg mass and hatchling production, as well as mean eggs/mass and number of hatchlings reaching maturity, did not differ significantly between aphallics and euphallics within control of exposed experimental groups. However, within the infected group euphallics produced 38% fewer eggs, smaller egg masses, and fewer hatchlings reaching maturity than aphallics, supporting the prediction of a cost to the growth and maintenance of a full male tract. This cost was detectable only when snails were under the stress of infection. The proportion of euphallic offspring produced did not differ across experimental groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of multiple Src family kinases in sea urchin eggs and their function in Ca2+ release at fertilization.

PubMed

Townley, Ian K; Schuyler, Erin; Parker-Gür, Michelle; Foltz, Kathy R

2009-03-15

Egg activation at fertilization in deuterostomes requires a rise in intracellular Ca(2+), which is released from the egg's endoplasmic reticulum. In sea urchins, a Src Family Kinase (SpSFK1) is necessary for the PLCgamma-mediated signaling event that initiates this Ca(2+) release (Giusti, A.F., O'Neill, F.J., Yamasu, K., Foltz, K.R. and Jaffe, L.A., 2003. Function of a sea urchin egg Src family kinase in initiating Ca2+ release at fertilization. Dev. Biol. 256, 367-378.). Annotation of the Strongylocentrotus purpuratus genome sequence led to the identification of additional, predicted SFKs (Bradham, C.A., Foltz, D.R., Beane, W.S., Amone, M.I., Rizzo, F., Coffman, J.A., Mushegian, A., Goel, M., Morales, J., Geneviere, A.M., Lapraz, F., Robertson, A.J., Kelkar, H., Loza-Coll, M., Townley, I.K., Raisch, M., Roux, M.M., Lepage, T., Gache, C., McClay, D.R., Manning, G., 2006. The sea urchin kinome: a first look. Dev. Biol. 300, 180-193.; Roux, M.M., Townley, I.K., Raisch, M., Reade, A., Bradham, C., Humphreys, G., Gunaratne, H.J., Killian, C.E., Moy, G., Su, Y.H., Ettensohn, C.A., Wilt, F., Vacquier, V.D., Burke, R.D., Wessel, G. and Foltz, K.R., 2006. A functional genomic and proteomic perspective of sea urchin calcium signaling and egg activation. Dev. Biol. 300, 416-433.). Here, we describe the cloning and characterization of these 4 additional SFKs and test their function during the initial Ca(2+) release at fertilization using the dominant-interfering microinjection method coupled with Ca(2+) recording. While two of the new SFKs (SpFrk and SpSFK3) are necessary for Ca(2+) release, SpSFK5 appears dispensable for early egg to embryo transition events. Interestingly, SpSFK7 may be involved in preventing precocious release of Ca(2+). Binding studies indicate that only SpSFK1 is capable of direct interaction with PLCgamma. Immunolocalization studies suggest that one or more SpSFK and PLCgamma are localized to the egg cortex and at the site of sperm-egg interaction. Collectively, these data indicate that more than one SFK is involved in the Ca(2+) release pathway at fertilization.

50 CFR 16.13 - Importation of live or dead fish, mollusks, and crustaceans, or their eggs.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., and crustaceans, or their eggs. 16.13 Section 16.13 Wildlife and Fisheries UNITED STATES FISH AND... Wildlife § 16.13 Importation of live or dead fish, mollusks, and crustaceans, or their eggs. (a) Upon an... their gametes or fertilized eggs, may be imported, transported, and possessed in captivity without a...

CRYPTIC CHOICE OF CONSPECIFIC SPERM CONTROLLED BY THE IMPACT OF OVARIAN FLUID ON SPERM SWIMMING BEHAVIOR

PubMed Central

Yeates, Sarah E; Diamond, Sian E; Einum, Sigurd; Emerson, Brent C; Holt, William V; Gage, Matthew J G

2013-01-01

Despite evidence that variation in male–female reproductive compatibility exists in many fertilization systems, identifying mechanisms of cryptic female choice at the gamete level has been a challenge. Here, under risks of genetic incompatibility through hybridization, we show how salmon and trout eggs promote fertilization by conspecific sperm. Using in vitro fertilization experiments that replicate the gametic microenvironment, we find complete interfertility between both species. However, if either species’ ova were presented with equivalent numbers of both sperm types, conspecific sperm gained fertilization precedence. Surprisingly, the species’ identity of the eggs did not explain this cryptic female choice, which instead was primarily controlled by conspecific ovarian fluid, a semiviscous, protein-rich solution that bathes the eggs and is released at spawning. Video analyses revealed that ovarian fluid doubled sperm motile life span and straightened swimming trajectory, behaviors allowing chemoattraction up a concentration gradient. To confirm chemoattraction, cell migration tests through membranes containing pores that approximated to the egg micropyle showed that conspecific ovarian fluid attracted many more spermatozoa through the membrane, compared with heterospecific fluid or water. These combined findings together identify how cryptic female choice can evolve at the gamete level and promote reproductive isolation, mediated by a specific chemoattractive influence of ovarian fluid on sperm swimming behavior. PMID:24299405

A calcium influx is triggered and propagates in the zygote as a wavefront during in vitro fertilization of flowering plants.

PubMed

Antoine, A F; Faure, J E; Cordeiro, S; Dumas, C; Rougier, M; Feijó, J A

2000-09-12

In this paper, we report direct measurement of an influx of extracellular Ca(2+) induced by gamete fusion in flowering plants. This result was obtained during maize in vitro fertilization with the use of an extracellular Ca(2+)-selective vibrating probe. Ca(2+) influx recorded at the surface of isolated egg cells, with or without adhesion of a male sperm cell, was close to zero and stable over time. Gamete fusion, however, triggered a Ca(2+) influx in the vicinity of the sperm entry site with a delay of 1.8 +/- 0.6 sec. The Ca(2+) influx spread subsequently through the whole egg cell plasma membrane as a wavefront, progressing at an estimated rate of 1.13 micrometer.(-1). Once established, Ca(2+) influx intensities were sustained, monotonic and homogeneous over the whole egg cell, with an average peak influx of 14.92 pmol .cm(-2).(-1) and an average duration of 24.4 min. The wavefront spread of channel activation correlates well with the cytological modifications induced by fertilization, such as egg cell contraction, and with the cytosolic Ca(2+) ((c)[Ca(2+)]) elevation previously reported. Calcium influx was inhibited effectively by gadolinium, possibly implicating mechanosensitive channels. Furthermore, artificial influxes created by incubation with Ca(2+) ionophores mimicked some aspects of egg activation. Taken together, these results suggest that, during fertilization in higher plants, gamete membrane fusion starts the first embryonic events by channel opening and Ca(2+) influx. In turn, (c)[Ca(2+)] may work as a trigger and possibly a space and time coordinator of many aspects of egg activation.

An oocyte-specific astacin family protease, alveolin, is released from cortical granules to trigger egg envelope hardening during fertilization in medaka (Oryzias latipes).

PubMed

Shibata, Yasushi; Iwamatsu, Takashi; Suzuki, Norio; Young, Graham; Naruse, Kiyoshi; Nagahama, Yoshitaka; Yoshikuni, Michiyasu

2012-12-15

It has long been hypothesized that in fishes the contents of cortical granules are involved in the hardening of egg envelope following fertilization. We previously purified the egg envelope hardening initiation factor from the exudates released from activated medaka (Oryzias latipes) eggs and tentatively termed this protein alveolin. Alveolin is a member of the astacin metalloprotease family and was proposed to be a protease which hydrolyzes ZPB at one restricted position to allow starting cross-linking with ZPC. Here, we investigated the complete pathway from biosynthesis and accumulation to secretion of alveolin. A single alveolin transcript was detected only in ovarian preparations, confirming the specific expression of alveolin in the ovary. In situ hybridization indicated that the alveolin mRNA is already expressed in the very early previtellogenic oocytes. However, immunocytochemical studies revealed that the appearance of alveolin protein was delayed until the beginning of the vitellogenic stage. The cortical granules isolated from unfertilized eggs contained a high molecular weight form of glycosylated alveolin with a 50kDa relative molecular mass. Hypotonic treatment burst isolated granules in vitro and transformed alveolin to a 21.5kDa form, which is the same size as that of natural alveolin released from eggs upon fertilization. This transformation was inhibited in the presence of leupeptin and 4-(2-aminoethyl) benzenesulfonyl fluoride hydrochloride (AEBSF), suggesting that a serine protease is involved in alveolin activation upon fertilization. Furthermore, the phylogenetic relationship of alveolin with other vertebrate astacin family members was analyzed. The result shows that alveolin and its teleostean homologs make a new group which is separate from either the hatching enzyme, meprin and BMP1/tolloid groups. Copyright © 2012 Elsevier Inc. All rights reserved.

Sexual selection for genetic compatibility: the role of the major histocompatibility complex on cryptic female choice in Chinook salmon (Oncorhynchus tshawytscha)

PubMed Central

Gessner, C; Nakagawa, S; Zavodna, M; Gemmell, N J

2017-01-01

Cryptic female choice (CFC), a form of sexual selection during or post mating, describes processes of differential sperm utilization by females to bias fertilization outcomes towards certain males. In Chinook salmon (Oncorhynchus tshawytscha) the ovarian fluid surrounding the ova of a given female differently enhances the sperm velocity of males. Sperm velocity is a key ejaculate trait that determines fertilization success in externally fertilizing fishes, thus the differential effect on sperm velocity might bias male fertilization outcomes and represent a mechanism of CFC. Once sperm reach the oocyte, CFC could potentially be further facilitated by sperm–egg interactions, which are well understood in externally fertilizing marine invertebrates. Here, we explored the potential genetic basis of both possible mechanisms of CFC by examining whether the genotypic combinations of mates (amino-acid divergence, number of shared alleles) at the major histocompatibility complex (MHC) class I and II explain the variation in sperm velocity and/or male fertilization success that is not explained by sperm velocity, which might indicate MHC-based sperm–egg interactions. We recorded sperm velocity in ovarian fluid, employed paired-male fertilization trials and evaluated the fertilization success of each male using microsatellite-based paternity assignment. We showed that relative sperm velocity was positively correlated with fertilization success, confirming that the differential effect on sperm velocity may be a mechanism of CFC in Chinook salmon. The variation in sperm velocity was independent of MHC class I and II. However, the MHC class II divergence of mates explained fertilization success, indicating that this locus might influence sperm–egg interactions. PMID:28051059

Changes in the concentrations of four maternal steroids during embryonic development in the threespined stickleback (Gasterosteus aculeatus).

PubMed

Paitz, Ryan Thomas; Mommer, Brett Christian; Suhr, Elissa; Bell, Alison Marie

2015-08-01

Embryonic exposure to steroids often leads to long-term phenotypic effects. It has been hypothesized that mothers may be able to create a steroid environment that adjusts the phenotypes of offspring to current environmental conditions. Complicating this hypothesis is the potential for developing embryos to modulate their early endocrine environment. This study utilized the threespined stickleback (Gasterosteus aculeatus) to characterize the early endocrine environment within eggs by measuring four steroids (progesterone, testosterone, estradiol, and cortisol) of maternal origin. We then examined how the concentrations of these four steroids changed over the first 12 days post fertilization (dpf). Progesterone, testosterone, estradiol, and cortisol of maternal origin could be detected within unfertilized eggs and levels of all four steroids declined in the first 3 days following fertilization. While levels of progesterone, testosterone, and estradiol remained low after the initial decline, levels of cortisol rose again by 8 dpf. These results demonstrate that G. aculeatus embryos begin development in the presence of a number of maternal steroids but levels begin to change quickly following fertilization. This suggests that embryonic processes change the early endocrine environment and hence influence the ability of maternal steroids to affect development. With these findings, G. aculeatus becomes an intriguing system in which to study how selection may act on both maternal and embryonic processes to shape the evolutionary consequence of steroid-mediated maternal effects. © 2015 Wiley Periodicals, Inc.

Evaluation of the Efficacy of Iodophor Disinfection of Walleye and Northern Pike Eggs to Eliminate Viral Hemorrhagic Septicemia Virus

USGS Publications Warehouse

Tuttle-Lau, M.T.; Phillips, K.A.; Gaikowski, M.P.

2009-01-01

Viral hemorrhagic septicemia virus (VHSv) is a serious fish pathogen that has been responsible for large-scale fish kills in the Great Lakes since 2005. It causes high mortality and resulting outbreaks have severe economic consequences for aquaculture. Iodophor disinfection of salmonid eggs is a standard hatchery practice to reduce the risk of pathogen transfer during gamete collection ('spawning') operations and is thus a leading candidate for reducing VHSv transmission during and after spawning of nonsalmonid fishes. However, before it is incorporated by hatcheries during nonsalmonid fish spawning efforts, its safety and effectiveness needs to be evaluated. The USGS Fact Sheet 2009-3107, 'Evaluation of the Efficacy of Iodophor Disinfection of Walleye and Northern Pike Eggs to Eliminate Viral Hemorrhagic Septicemia Virus' presents the results of a study to assess the effectiveness of iodophor disinfection for eliminating VHSv (strain IVb) from fertilized eggs of walleye and northern pike intentionally challenged with VHSv following egg fertilization. Walleye and northern pike egg survival (hatch) following iodophor egg disinfection also was assessed.

Toxicity of TFM lampricide to early life stages of walleye

USGS Publications Warehouse

Seelye, J.G.; Marking, L.L.; King, E.L.; Hanson, L.H.; Bills, T.D.

1987-01-01

The authors studied the effects of the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) on gametes, newly fertilized eggs, eyed eggs, larvae, and swim-up fry of the walleye Stizostedion vitreum . When gametes from sexually mature walleyes were stripped into solutions of TFM, no effects were observed during the fertilization process at concentrations up to 3.0 mg/L - three times the concentration lethal to 99.9% of larval sea lampreys Petromyzon marinus held 12 h (LC99.9) under the same test conditions. Newly fertilized eggs likewise were unaffected during water hardening by concentrations of TFM that were lethal to sea lamprey ammocoetes. Eyed eggs, sac fry, and swim-up fry yielded LC25 values that were 2.5 to 5 times greater than the 12-h LC99.9 for sea lamprey ammocoetes. The data thus indicated that all of the early life stages of walleyes tested were considerably more resistant than sea lamprey ammocoetes to TFM, and that it is unlikely they would be adversely affected by standard stream treatments to kill sea lamprey ammocoetes.

An Electron Microscope Study of the Rat Ovum

PubMed Central

Sotelo, J. Roberto; Porter, Keith R.

1959-01-01

This paper reports on the fine structure of rat oocytes at stages before ovulation, during maturation, fertilization, and early cleavage. The study includes parallel observations on light and electron microscope preparations with attempted correlations. The follicular cells of the ovarian egg are described as sending long processes through the zona pellucida to the egg surface where they mingle with thin projections from the egg itself. No open communication between follicle cell cytoplasm and egg cytoplasm was observed. During maturation and fertilization both types of processes are withdrawn from the zona. The germinal vesicle and later the pronuclei of the fertilized egg are characterized by numerous large nucleoli. These have the form of thick walled vesicles with diameters as great as 8 to 10 µ. The wall is dense in the EM image and appears to consist in part of small granules. The cytoplasm shows several inclusions including mitochondria of usual form and a Golgi component which has the typical fine structure and the distribution described by earlier light studies. Small dense particles, presumably RNP particles, are distributed throughout the cytoplasmic matrix and show no preference for membranes. The endoplasmic reticulum of the oocyte is represented by a scattering only of vesicles, but begins a more extensive and elaborate development with the onset of segmentation. One inclusion of the ooplasm, similar in size to mitochondria, receives special attention. It is a vesicular structure, containing a large number of small vesicles (10 to 50 mµ in diameter) and frequently a central density or nucleoid. They are referred to as multivesicular bodies. Such bodies are found in small number in the ovarian egg, but increase greatly in number during maturation and fertilization. It appears from the micrographs of eggs in these latter stages that these vesicular bodies break down and liberate their content of small vesicles to the surrounding ooplasm. Comments are provided on the apparent significance of the various observations. PMID:13654454

Histological study on maturation, fertilization and the state of gonadal region following spawning in the model sea anemone, Nematostella vectensis

PubMed Central

Moiseeva, Elizabeth; Rabinowitz, Claudette; Rinkevich, Baruch

2017-01-01

The starlet sea-anemone Nematostella vectensis has emerged as a model organism in developmental biology. Still, our understanding of various biological features, including reproductive biology of this model species are in its infancy. Consequently, through histological sections, we study here key stages of the oogenesis (oocyte maturation/fertilization), as the state of the gonad region immediately after natural spawning. Germ cells develop in a secluded mesenterial gastrodermal zone, where the developing oocytes are surrounded by mucoid glandular cells and trophocytes (accessory cells). During vitellogenesis, the germinal vesicle in oocytes migrates towards the animal pole and the large polarized oocytes begin to mature, characterized by karyosphere formation. Then, the karyosphere breaks down, the chromosomes form the metaphase plate I and the eggs are extruded from the animal enclosed in a sticky, jelly-like mucoid mass, along with numerous nematosomes. Fertilization occurs externally at metaphase II via swimming sperm extruded by males during natural spawning. The polar bodies are ejected from the eggs and are situated within a narrow space between the egg’s vitelline membrane and the adjacent edge of the jelly coat. The cortical reaction occurs only at the polar bodies’ ejection site. Several spermatozoa can penetrate the same egg. Fertilization is accompanied by a strong ooplasmatic segregation. Immediately after spawning, the gonad region holds many previtellogenic and vitellogenic oocytes, though no oocytes with karyosphere. Above are the first histological descriptions for egg maturation, meiotic chromosome’s status at fertilization, fertilization and the gonadal region’s state following spawning, also documenting for the first time the ejection of the polar body. PMID:28796817

Spectral interferometry for morphological imaging in in vitro fertilization (IVF) (Conference Presentation)

NASA Astrophysics Data System (ADS)

Zhu, Yizheng; Li, Chengshuai

2016-03-01

Morphological assessment of spermatozoa is of critical importance for in vitro fertilization (IVF), especially intracytoplasmic sperm injection (ICSI)-based IVF. In ICSI, a single sperm cell is selected and injected into an egg to achieve fertilization. The quality of the sperm cell is found to be highly correlated to IVF success. Sperm morphology, such as shape, head birefringence and motility, among others, are typically evaluated under a microscope. Current observation relies on conventional techniques such as differential interference contrast microscopy and polarized light microscopy. Their qualitative nature, however, limits the ability to provide accurate quantitative analysis. Here, we demonstrate quantitative morphological measurement of sperm cells using two types of spectral interferometric techniques, namely spectral modulation interferometry and spectral multiplexing interferometry. Both are based on spectral-domain low coherence interferometry, which is known for its exquisite phase determination ability. While spectral modulation interferometry encodes sample phase in a single spectrum, spectral multiplexing interferometry does so for sample birefringence. Therefore they are capable of highly sensitive phase and birefringence imaging. These features suit well in the imaging of live sperm cells, which are small, dynamic objects with only low to moderate levels of phase and birefringence contrast. We will introduce the operation of both techniques and demonstrate their application to measuring the phase and birefringence morphology of sperm cells.

TIME RELATIONSHIPS IN THE CLEAVAGE OF THE NORMAL FERTILIZED EGG OF ARBACIA PUNCTULATA

PubMed Central

Blum, Harold F.; Price, Judith P.

1950-01-01

Quantitative data are presented indicating the extent of variability in the time of cleavage of normal fertilized eggs of Arbacia punctulata. It is a pleasure to acknowledge the valuable suggestions and criticisms of Professor Arthur K. Parpart during the course of the experiments described in this and the preceding paper, and those of Professor Douglas A. Marsland and Professor M. J. Kopac at the final manuscript stage. PMID:15406367

Sterilization of sea lampreys (Petromyzon marinus) by immersion in an aqueous solution of bisazir

USGS Publications Warehouse

Hanson, Lee H.

1981-01-01

Groups of sea lamprey (Petromyzon marinus) eggs fertilized by males previously immersed in an aqueous solution of p,p-bis(1-aziridinyl)-N-methylphosphinothioic amide (bisazir) at concentrations of 10–100 mg/L produced fewer normal, live prolarvae after 15–17 d of incubation than did groups of eggs fertilized by normal males. Mortality of embryos or prolarvae was nearly 100% in groups of eggs fertilized by males that had been immersed in a 50 mg/L solution of bisazir for 4 h or in a 100 mg/L solution for 2 h. The immersion technique appears to be an efficient method of sterilizing large numbers of male sea lampreys for use in a proposed sterile-male-release program.Key words: sea lamprey, Petromyzon marinus; pest control, fish control, sterile-male technique, sterilization, chemosterilants, bisazir, Great Lakes

31 CFR 538.523 - Commercial sales, exportation, and reexportation of agricultural commodities, medicine, and...

Code of Federal Regulations, 2010 CFR

2010-07-01

... drinking water) or animals (including animal feeds); (B) Seeds for food crops; (C) Fertilizers or organic fertilizers; or (D) Reproductive materials (such as live animals, fertilized eggs, embryos, and semen) for the... fertilizers, live horses, western red cedar, and medical devices other than basic medical supplies, such as...

31 CFR 560.530 - Commercial sales, exportation, and reexportation of agricultural commodities, medicine, and...

Code of Federal Regulations, 2010 CFR

2010-07-01

... water) or animals (including animal feeds); (B) Seeds for food crops; (C) Fertilizers or organic fertilizers; or (D) Reproductive materials (such as live animals, fertilized eggs, embryos, and semen) for the... exportation or reexportation of all fertilizers, live horses, western red cedar, and medical devices other...

Sperm transport and retention at the fertilization site is orchestrated by a chemical guidance and oviduct movement.

PubMed

Guidobaldi, H A; Teves, M E; Uñates, D R; Giojalas, L C

2012-05-01

In mammals, only a few spermatozoa arrive at the fertilization site. During the last step in the journey to the egg, apart from their self-propulsion, spermatozoa may be assisted by oviduct movement and/or a guidance mechanism. The proportion of rabbit spermatozoa that arrive at the fertilization site was determined under in vivo conditions, in which either the ovulation products (secreting chemoattractants) and/or the oviduct movement (causing the displacement of the oviductal fluid) was inhibited. When only one of these components was inhibited, sperm transport to the fertilization site was partially reduced. However, when both the ovulation products and the oviduct movement were inhibited, almost no spermatozoa arrived at the fertilization site. The results suggest that spermatozoa are transported to and retained at the fertilization site by the combined action of a chemical guidance and the oviduct movement. A working model is proposed to explain how these two mechanisms may operate to transport spermatozoa to the fertilization site, probably as an evolutionary adaptation to maximize the chance of fertilizing an egg.

Stability of post-fertilization traveling waves

NASA Astrophysics Data System (ADS)

Flores, Gilberto; Plaza, Ramón G.

This paper studies the stability of a family of traveling wave solutions to the system proposed by Lane et al. [D.C. Lane, J.D. Murray, V.S. Manoranjan, Analysis of wave phenomena in a morphogenetic mechanochemical model and an application to post-fertilization waves on eggs, IMA J. Math. Appl. Med. Biol. 4 (4) (1987) 309-331], to model a pair of mechanochemical phenomena known as post-fertilization waves on eggs. The waves consist of an elastic deformation pulse on the egg's surface, and a free calcium concentration front. The family is indexed by a coupling parameter measuring contraction stress effects on the calcium concentration. This work establishes the spectral, linear and nonlinear orbital stability of these post-fertilization waves for small values of the coupling parameter. The usual methods for the spectral and evolution equations cannot be applied because of the presence of mixed partial derivatives in the elastic equation. Nonetheless, exponential decay of the directly constructed semigroup on the complement of the zero eigenspace is established. We show that small perturbations of the waves yield solutions to the nonlinear equations decaying exponentially to a phase-modulated traveling wave.

Role of tetraspanin CD9 molecule in fertilization of mammals.

PubMed

Jankovičová, J; Simon, M; Antalíková, J; Cupperová, P; Michalková, K

2015-01-01

Fertilization process is a very clever and unique process comprising some essential steps resulting in formation of zygote. Tetraspanin CD9 is considered to be a serious candidate molecule participating in these events. The importance of CD9 has been discussed in relation to acrosome reaction, sperm-binding, sperm-penetration, sperm-egg fusion and eventually, egg activation. The abundant expression of CD9 oocyte plasma membrane and the presence of CD9-containing vesicles in the perivitelline space of intact oocytes have been confirmed. Despite the fact that majority of authors analyzed CD9 expressed on oocytes, several studies considered the function of sperm CD9, too. To understand CD9 involvement, various conditions of in vitro fertilization (IVF) assays using polyclonal as well as monoclonal antibodies or knockout mice were carried out. However, ambiguous data have been obtained about the importance of CD9 in sperm-egg binding or fusion. Although the current findings did not prove any hypothesis, the indispensable role of CD9 in fertilization process was not excluded and the precise role of CD9 remains unexplained.

Surface hydrocarbons of queen eggs regulate worker reproduction in a social insect

PubMed Central

Endler, Annett; Liebig, Jürgen; Schmitt, Thomas; Parker, Jane E.; Jones, Graeme R.; Schreier, Peter; Hölldobler, Bert

2004-01-01

A hitherto largely unresolved problem in behavioral biology is how workers are prevented from reproducing in large insect societies with high relatedness. Signals of the queen are assumed to inform the nestmates about her presence in the colony, which leads to indirect fitness benefits for workers. In the ant Camponotus floridanus, we found such a signal located on queen-laid eggs. In groups of workers that were regularly provided with queen-laid eggs, larvae, and cocoons, with larvae and cocoons alone, or with no brood, only in the groups with queen-laid eggs did workers not lay eggs. Thus, the eggs seem to inform the nestmates about the queen's presence, which induces workers to refrain from reproducing. The signal on queen-laid eggs is presumably the same that enables workers to distinguish between queen- and worker-laid eggs. Despite their viability, the latter are destroyed by workers when given a choice between both types. Queen- and worker-laid eggs differ in their surface hydrocarbons in a way similar to the way fertile queens differ from workers in the composition of their cuticular hydrocarbons. When we transferred hydrocarbons from the queen cuticle to worker-laid eggs, the destruction of those eggs was significantly mitigated. We conclude that queen-derived hydrocarbon labels inform workers about the presence of a fertile queen and thereby regulate worker reproduction. PMID:14993614

Effects of Oscillatory Flow on Fertilization in the Green Sea Urchin Strongylocentrotus droebachiensis

PubMed Central

Kregting, Louise T.; Bass, Anna L.; Guadayol, Òscar; Yund, Philip O.; Thomas, Florence I. M.

2013-01-01

Broadcast spawning invertebrates that live in shallow, high-energy coastal habitats are subjected to oscillatory water motion that creates unsteady flow fields above the surface of animals. The frequency of the oscillatory fluctuations is driven by the wave period, which will influence the stability of local flow structures and may affect fertilization processes. Using an oscillatory water tunnel, we quantified the percentage of eggs fertilized on or near spawning green sea urchins, Strongylocentrotus droebachiensis. Eggs were sampled in the water column, wake eddy, substratum and aboral surface under a range of different periods (T = 4.5 – 12.7 s) and velocities of oscillatory flow. The root-mean-square wave velocity (rms(u w)) was a good predictor of fertilization in oscillatory flow, although the root-mean-square of total velocity (rms(u)), which incorporates all the components of flow (current, wave and turbulence), also provided significant predictions. The percentage of eggs fertilized varied between 50 – 85% at low flows (rms(u w) <0.02 m s−1), depending on the location sampled, but declined to below 10% for most locations at higher rms(u w). The water column was an important location for fertilization with a relative contribution greater than that of the aboral surface, especially at medium and high rms(u w) categories. We conclude that gametes can be successfully fertilized on or near the parent under a range of oscillatory flow conditions. PMID:24098766

Cryopreservation of epididymal stallion sperm.

PubMed

Olaciregui, M; Gil, L; Montón, A; Luño, V; Jerez, R A; Martí, J I

2014-02-01

Any event that makes semen collection or mating impossible, such as death, castration, or injury, may terminate a stallion's breeding career. Fortunately, stallion sperm which are capable of fertilization can be harvested from the epididymis, and frozen for future use. However, the fertility of frozen-thawed epididymal sperm has been found to be lower than that of ejaculated sperm. Therefore, this study aimed to optimize the fertility of frozen epididymal stallion sperm by investigating the effects of different cryoprotectants and freezing protocols on sperm quality. Dimethylformamide was tested alone or combination with pasteurized egg yolk as substitute of fresh egg yolk. In addition, the effect of the pre-freeze stabilization on sperm quality was analyzed. Heterospermic samples obtained from stallion epididymis were collected and cryopreserved in lactose-egg-yolk extender or in the same extender with varying content of cryoprotectant and content of egg yolk, stabilized and no-stabilized. Sperm motility, viability, hypoosmotic swelling test (HOST) and acrosome integrity were evaluated post-thawing. No improvement was observed on the replacement of fresh yolk by pasteurized egg yolk, whereas the results suggest that dimethylformamide is a cryoprotectant suitable for cryopreservation of equine epididymal semen, even better than glycerol. In addition, we found that the stabilization before freezing on epididymal stallion sperm, can improve sperm quality parameters. Copyright © 2014 Elsevier Inc. All rights reserved.

Oxygen requirements of separated hybrid catfish female Ictalurus punctatus male I. furcatus eggs

USDA-ARS?s Scientific Manuscript database

Channel catfish Ictalurus punctatus egg masses require ambient water with over 95% air saturation to maintain maximum oxygen consumption as they near hatch. Since hybrid catfish eggs (channel catfish ' X blue catfish I. furcatus ') are often kept separated after fertilization by the addition of full...

Investigation of thiamine and PCB association with early life stage fry mortality in lake trout from northwestern Lake Michigan in 1996-1998

USGS Publications Warehouse

Honeyfield, Dale C.; Beltman, Dong; Holey, Mark; Edsall, Carol C.

2005-01-01

Lake trout (Salvelinus namaycush) eggs were collected from 72 females near Sturgeon Bay, WI in northwestern Lake Michigan from 1996, 1997, and 1998 to determine the relationships between egg thiamine and polychlorinated biphenyl (PCB) concentrations with egg fertilization and hatch, prevalence of abnormal fry, and fry mortality. Fry mortality consistent with early mortality syndrome (EMS) was observed in eggs from 33% of the females in 1996, 25% in 1997, and 28% in 1998. Among egg lots exhibiting EMS, fry mortality averaged 95% in 1996, 63% in 1997 and 77% in 1998 compared to 2% or less in lots that did not exhibit EMS. Expression of EMS was strongly correlated with egg thiamine concentrations; egg lots with less than approximately 1 nmol/g total thiamine consistently exhibited high rates of EMS, whereas egg batches with greater than 1.5 nmol/g showed little or no incidence of EMS among swim-up fry. Egg thiamine concentration was not related to fertilization rate, egg hatch, or the prevalence of abnormal fry. There was no relationship between egg concentrations of PCBs or tetrachlorinated dibenzo-p-dioxin (TCDD) equivalents (from PCBs, dioxins, and furans) and any of the egg or fry viability measurements, including EMS. We concluded that fry mortality observed in Lake Michigan lake trout in 1996-1998 was not caused by the toxicity of PCBs, dioxins, and furans, but is due to low egg thiamine concentrations.

An evaluation of soybean lecithin as an alternative to avian egg yolk in the cryopreservation of fish sperm.

PubMed

Yildiz, Cengiz; Bozkurt, Yusuf; Yavas, Ilker

2013-08-01

Plant-derived lecithin has been used as a more sanitary alternative to avian egg yolk in livestock sperm cryopreservation protocols but its efficacy for cryopreserving fish sperm has not previously been tested comparatively. Here various concentrations of soybean lecithin were evaluated for the cryopreservation of carp (Cyprinus carpio) sperm. Sexually mature fish were induced to spermiation and ovulation with ovopel. The extenders were prepared by using 300 mM glucose, 10% DMSO, supplemented with different ratios of lecithin (5%, 10%, 15%, and 20%) and 10% egg yolk (control I). Negative control was made without egg yolk and soybean lecithin (control II). The pooled semen was diluted separately at ratio of 1:3 (v/v) by using egg yolk and soybean-based extenders. Diluted semen placed into 0.25 ml straws were equilibrated at 4 °C for 15 min and frozen in liquid nitrogen vapor. Fertilization was conducted using a ratio of 1 × 10(5)spermatozoa/egg. Supplementation of 10% lecithin to extender showed the best cryoprotective effect for sperm motility and duration of motility against freezing damage compared to 15%, 20% and control II groups (p<0.05). Cryopreserved sperm with extender containing 10% lecithin provided a greater result in terms of fertilization success when compared to extenders containing 20% lecithin or control II (p<0.05). It is concluded that the animal protein-free extender containing 10% soybean lecithin has a similar cryoprotective actions with conventional egg yolk-based extender against freezing damages and fertilization. Therefore, soybean lecithin is a suitable alternative to avian egg yolk for the cryopreservation of fish sperm. Copyright © 2013 Elsevier Inc. All rights reserved.

Reproductive success, early life stage development, and survival of westslope cutthroat trout (Oncorhynchus clarki lewisi) exposed to elevated selenium in an area of active coal mining

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barri-Lynn Rudolph; Iisak Andreller; Christopher J. Kennedy

2008-04-15

The effects of accumulated Se on the reproductive success and larval development of cutthroat trout (Oncorhynchus clarki lewisi) collected from a site of active coal mining in British Columbia were assessed. Eggs from 12 fish from an exposed site (Clode Pond) and 16 from a reference site (O'Rourke Lake) were field-collected and reared in the laboratory. Egg Se concentrations ranged from 12.3 to 16.7 and 11.8 to 140.0 {mu}g/g dry weight (dw) from fish collected at the reference and exposed sites, respectively. Other studies, including those with this species, have not shown Se to affect egg viability. However, in themore » present study, eggs with Se concentrations >86.3 {mu}g/g dw were not successfully fertilized or were nonviable at fertilization, while eggs with concentrations >46.8 and <75.4 {mu}g/g dw were fertilized (96% reached the eyed stage) but did not produce viable fry. A significant positive relationship between egg Se concentration and alevin mortality was observed. Deformities were analyzed in surviving fry which developed from eggs with Se concentrations between 11.8 and 20.6 {mu}g/g dw. No relationship between Se concentration in eggs and deformities or edema was found in this range, suggesting that the no-effect threshold for deformity is >20.6 {mu}g/g dw. The present data, in conjunction with the data from several other studies in temperate fish, suggest that current Se thresholds are conservative for cold-water fish. 25 refs., 3 figs.« less

ZP Domain Proteins in the Abalone Egg Coat Include a Paralog of VERL under Positive Selection That Binds Lysin and 18-kDa Sperm Proteins

PubMed Central

Aagaard, Jan E.; Vacquier, Victor D.; MacCoss, Michael J.; Swanson, Willie J.

2010-01-01

Identifying fertilization molecules is key to our understanding of reproductive biology, yet only a few examples of interacting sperm and egg proteins are known. One of the best characterized comes from the invertebrate archeogastropod abalone (Haliotis spp.), where sperm lysin mediates passage through the protective egg vitelline envelope (VE) by binding to the VE protein vitelline envelope receptor for lysin (VERL). Rapid adaptive divergence of abalone lysin and VERL are an example of positive selection on interacting fertilization proteins contributing to reproductive isolation. Previously, we characterized a subset of the abalone VE proteins that share a structural feature, the zona pellucida (ZP) domain, which is common to VERL and the egg envelopes of vertebrates. Here, we use additional expressed sequence tag sequencing and shotgun proteomics to characterize this family of proteins in the abalone egg VE. We expand 3-fold the number of known ZP domain proteins present within the VE (now 30 in total) and identify a paralog of VERL (vitelline envelope zona pellucida domain protein [VEZP] 14) that contains a putative lysin-binding motif. We find that, like VERL, the divergence of VEZP14 among abalone species is driven by positive selection on the lysin-binding motif alone and that these paralogous egg VE proteins bind a similar set of sperm proteins including a rapidly evolving 18-kDa paralog of lysin, which may mediate sperm–egg fusion. This work identifies an egg coat paralog of VERL under positive selection and the candidate sperm proteins with which it may interact during abalone fertilization. PMID:19767347

Effects of Toxic Compounds in Montipora capitata on Exogenous and Endogenous Zooxanthellae Performance and Fertilization Success

PubMed Central

Hagedorn, Mary; Farrell, Ann; Carter, Virginia; Zuchowicz, Nikolas; Johnston, Erika; Padilla-Gamiño, Jacqueline; Gunasekera, Sarath; Paul, Valerie

2015-01-01

Studies have identified chemicals within the stony coral genus Montipora that have significant biological activities. For example, Montiporic acids A and B and other compounds have been isolated from the adult tissue and eggs of Montipora spp. and have displayed antimicrobial activity and cytotoxicity in cultured cells. The ecological role of these toxic compounds is currently unclear. This study examines the role these toxins play in reproduction. Toxins were found in the eggs and larvae of the coral Montipora capitata. Releasing these toxins by crushing both the eggs and larvae resulted in irreversible inhibition of photosynthesis in endogenous and exogenous zooxanthellae within minutes. Moreover, these toxins were stable, as frozen storage of eggs and larvae did not affect toxicity. Photosynthetic competency of Porites compressa zooxanthellae treated with either frozen or fresh, crushed eggs was inhibited similarly (P > 0.05, ANCOVA). Addition of toxic eggs plugs to live P. compressa fragments caused complete tissue necrosis under the exposed area on the fragments within 1 week. Small volumes of M. capitata crushed eggs added to sperm suspensions reduced in vitro fertilization success by killing the sperm. After 30 min, untreated sperm maintained 90 ± 1.9% SEM motility while those treated with crushed eggs were rendered immotile, 4 ± 1.4% SEM. Flow cytometry indicated membrane disruption of the immotile sperm. Fertilization success using untreated sperm was 79 ± 4% SEM, whereas the success rate dropped significantly after exposure to the crushed eggs, 1.3 ± 0% SEM. Unlike the eggs and the larvae, M. capitata sperm did not reduce the photosynthetic competency of P. compressa zooxanthellae, suggesting the sperm was nontoxic. The identity of the toxins, cellular mechanism of action, advantage of the toxins for M. capitata and their role on the reef are still unknown. PMID:25714606

Influence of pre-storage incubation on hatchability traits, thyroid hormones, antioxidative status and immunity of newly hatched chicks at two chicken breeder flock ages.

PubMed

Ebeid, T A; Twfeek, F A; Assar, M H; Bealish, A M; Abd El-Karim, R E; Ragab, M

2017-11-01

Egg storage longer than 7 days is associated with negative effects on hatchability traits. Pre-storage incubation has been a suggested method to reduce the negative effects of long-term storage times by enhancing the developmental stage of the embryo and probably reducing the embryonic stress. The objective of the present study was to investigate the effects of pre-storage incubation and storage time on hatchability characteristics, chick quality and serum thyroid hormones, antioxidative properties and immunoglobulin Y (IgY) concentrations of newly hatched chicks at two breeder flock ages. A total of 8000 fertile eggs were obtained from two different ages of chicken breeder hens (Egyptian local cross, Inshas). Half of the eggs were collected from young breeder hens (28 weeks old) and the other half from old breeder hens (50 weeks old). In each breeder flock age, eggs were distributed in a completely randomized experimental design in a 2×4 factorial arrangement, with two storage periods (4 or 14 days) and four pre-storage incubation durations (0, 4, 6 or 8 h at 37.5°C). At 28 and 50 weeks of age, pre-storage incubation and its interaction with storage period influenced significantly the apparent fertility, hatchability of set eggs and hatchability of fertile eggs and this improvement in hatchability is attributed to the reduction in embryonic mortality (early, intermediate and late). Pre-storage incubation for 6 or 8 h elevated significantly the grade A chicks and reduced the grade B chicks in comparison with non-heated controls. Interestingly, for eggs stored for 14 days, pre-storage incubation for 6 or 8 h enhanced serum triiodothyronine, thyroxine, glutathione peroxidase activity, total antioxidant capacity and IgY concentrations significantly and decreased serum malondialdehyde concentration significantly in the newly hatched chicks. It could be concluded that pre-storage incubation enhanced the hatching results, improved the antioxidative properties, reduced lipid peroxidation and elevated the humoral immunity in the newly hatched chicks. Hence, several benefits might be gained by pre-storage incubation when fertilized eggs will be stored for long periods.

Soya-lecithin in extender improves the freezability and fertility of buffalo (Bubalus bubalis) bull spermatozoa.

PubMed

Akhter, S; Ansari, M S; Andrabi, S M H; Rakha, B A; Ullah, N; Khalid, M

2012-10-01

Egg yolk is routinely used as a cryoprotectant in semen extenders. However, it may contain cryoprotective antagonists, and there are hygienic risks associated with its use. Proteins of plant origin, like soya-lecithin, lack these hazards. The aim of this study was to use soya-lecithin as a cryoprotectant in extender and to investigate its effects on in vitro quality and in vivo fertility of buffalo semen. Semen from three buffalo bulls was frozen in tris-citric extender containing 5.0%, 10% or 15% soya-lecithin or 20% egg yolk. Sperm motility, plasma membrane integrity and viability were assessed post-dilution, pre-freezing and post-thaw. In Post-dilution and pre-freezing, the values for motility, plasma membrane integrity and viability remained higher (p ≤ 0.05) in extenders containing 10% soya-lecithin and control compared with extender containing 5% and 15% soya-lecithin. However, motility, plasma membrane integrity and viability were higher (p < 0.05) in extender containing 10% soya-lecithin compared with control and extenders containing 5% and 15% soya-lecithin. Semen from two buffalo bulls was frozen in tris-citric extender containing either 10% soya-lecithin or 20% egg yolk. Higher (p < 0.05) fertility rate was recorded in buffaloes inseminated with semen containing 10% soya-lecithin (56%) compared with 20% egg yolk (41.5%). The results suggest that 10% soya-lecithin in extender improves the freezability and fertility of buffalo bull spermatozoa and can be used as an alternate to egg yolk in cryopreservation of buffalo semen. © 2011 Blackwell Verlag GmbH.

Trust women to choose: a response to John a Robertson's 'Egg freezing and Egg banking: empowerment and alienation in assisted reproduction'.

PubMed

Goold, Imogen

2017-12-01

In 'Egg Freezing and Egg Banking: Empowerment and Alienation in Assisted Reproduction', John A Robertson responds to the American Society of Reproductive Medicine's statement that oocyte preservation should no longer be considered an experimental treatment. He explores the implications of this development, focusing on the potentially empowering impact of oocyte preservation as a means for women to preserve their fertility. He also engages with concerns about the possibility that such a development may raise issues of alienation. He highlights some of the potential problems that may emerge as women gain the capacity to store and either donate or sell any eggs they do not need for their own reproductive purposes. Much of his paper is valuable and considered, but in places, his views rest on assumptions about women's attitudes to their fertility, understanding of the technology, and relationship with their gametes that are open to dispute. This paper teases out some of these assumptions and puts pressure on them by drawing on the growing body of data about what women actually do think and feel about fertility issues. It focuses on two of his main concerns-that social egg freezing may give women a false sense of security and that women may be harmed if a market in eggs leads to their alienation from their gametes. Via this response to Robertson, I aim to redress the tendency often seen in discussions around women, infertility, aging, and empowerment to unquestioningly accept what I argue are stereotypes and assumptions about women's views and capacity to reason.

Effects of host genetics and environment on egg-associated microbiotas in brown trout (Salmo trutta).

PubMed

Wilkins, Laetitia G E; Fumagalli, Luca; Wedekind, Claus

2016-10-01

Recent studies found fish egg-specific bacterial communities that changed over the course of embryogenesis, suggesting an interaction between the developing host and its microbiota. Indeed, single-strain infections demonstrated that the virulence of opportunistic bacteria is influenced by environmental factors and host immune genes. However, the interplay between a fish embryo host and its microbiota has not been studied yet at the community level. To test whether host genetics affects the assemblage of egg-associated bacteria, adult brown trout (Salmo trutta) were sampled from a natural population. Their gametes were used for full-factorial in vitro fertilizations to separate sire from dam effects. In total, 2520 embryos were singly raised under experimental conditions that differently support microbial growth. High-throughput 16S rRNA amplicon sequencing was applied to characterize bacterial communities on milt and fertilized eggs across treatments. Dam and sire identity influenced embryo mortality, time until hatching and composition of egg-associated microbiotas, but no link between bacterial communities on milt and on fertilized eggs could be found. Elevated resources increased embryo mortality and modified bacterial communities with a shift in their putative functional potential. Resource availability did not significantly affect any parental effects on embryo performance. Sire identity affected bacterial diversity that turned out to be a significant predictor of hatching time: embryos associated with high bacterial diversity hatched later. We conclude that both host genetics and the availability of resources define diversity and composition of egg-associated bacterial communities that then affect the life history of their hosts. © 2016 John Wiley & Sons Ltd.

OBSERVATIONS ON THE UPTAKE OF TRITIATED THYMIDINE IN THE PRONUCLEI OF FERTILIZED SAND DOLLAR EMBRYOS.

PubMed

Simmel, E B; Karnofsky, D A

1961-05-01

Following fertilization of the egg of the sand dollar Echinarachnius parma, tritiated thymidine (H(3)TDR) was taken up independently by the male and female pronuclei beginning within about 15 to 20 minutes, and the labeled pronuclei fused at about 30 to 40 minutes. At cleavage 90 minutes later the labeled nuclear material was distributed to both daughter cells. Unfertilized eggs and sperm exposed to H(3)TDR did not show nuclear localization of thymidine. DNA replication, thus, is initiated in the haploid pronuclei shortly after fertilization and prior to fusion. The major portion of DNA synthesis, as evidenced by thymidine uptake, appears to be during a 20 to 30 minute period after fertilization. Fertilization is associated with the activation of a mechanism which initiates early and independent replication of DNA in both the male and female pronuclei.

OBSERVATIONS ON THE UPTAKE OF TRITIATED THYMIDINE IN THE PRONUCLEI OF FERTILIZED SAND DOLLAR EMBRYOS

PubMed Central

Simmel, Eva B.; Karnofsky, David A.

1961-01-01

Following fertilization of the egg of the sand dollar Echinarachnius parma, tritiated thymidine (H3TDR) was taken up independently by the male and female pronuclei beginning within about 15 to 20 minutes, and the labeled pronuclei fused at about 30 to 40 minutes. At cleavage 90 minutes later the labeled nuclear material was distributed to both daughter cells. Unfertilized eggs and sperm exposed to H3TDR did not show nuclear localization of thymidine. DNA replication, thus, is initiated in the haploid pronuclei shortly after fertilization and prior to fusion. The major portion of DNA synthesis, as evidenced by thymidine uptake, appears to be during a 20 to 30 minute period after fertilization. Fertilization is associated with the activation of a mechanism which initiates early and independent replication of DNA in both the male and female pronuclei. PMID:19866590

Fertilization stimulates an increase in inositol trisphosphate and inositol lipid levels in Xenopus eggs.

PubMed

Snow, P; Yim, D L; Leibow, J D; Saini, S; Nuccitelli, R

1996-11-25

Previous experiments from our lab have suggested that the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) is required for sperm-induced egg activation in Xenopus laevis. Here we measure the endogenous production of both Ins(1,4,5)P3 and PIP2 during the sperm-induced and ionomycin-induced calcium wave in the egg and find that both increase following fertilization. Ins(1,4,5)P3 increases 3.2-fold from an unfertilized egg level of 0.13 pmole per egg (0.29 microM) to a peak of 0.42 pmole per egg (0.93 microM) as the calcium wave reaches the antipode in the fertilized egg. This continuous production of Ins(1,4,5)P3 during the time that the Ca2+ wave is propagating across the egg suggests the involvement of Ins(1,4,5)P3 in wave propagation. This increase in Ins(1,4,5)P3 is smaller in ionomycin-activated eggs than in sperm-activated eggs, suggesting that the sperm-induced production of Ins(1,4,5)P3 involves a PIP2 hydrolysis pathway that is not simply raising intracellular Ca2+. While one might expect PIP2 levels to fall as a result of hydrolysis, we find that PIP2 actually increases 2-fold. The total lipid fraction in unfertilized egg exhibits 0.8 pmole PIP2 per egg and this increases to 1.5 pmole as the calcium wave reaches the antipode. The PIP2 concentration peaks 2 min after the completion of the calcium wave at 1.8 pmole per egg. The amount of PIP2 in the animal and vegetal hemispheres of the egg was also measured by cutting frozen eggs in half. The vegetal hemisphere contained twice the amount of PIP2 as the animal hemisphere but it also contained twice the amount of lipid. Thus, there was an equivalent amount of PIP2 normalized to lipid in each hemisphere. Isolated animal and vegetal hemisphere cortices exhibit similar PIP2 concentrations, suggesting that the 2-fold higher total PIP2 in the vegetal half is not due to a gradient of PIP2 in the plasma membrane, but rather implies that cytoplasmic organelle membranes also contain PIP2.

Effect of the combination of white and red LED lighting during incubation on layer, broiler, and Pekin duck hatchability.

PubMed

Archer, G S; Jeffrey, D; Tucker, Z

2017-08-01

Previous research has shown that providing light during incubation can have positive effects on hatchability and chick quality; however, white light alone has been observed to improve these factors only in pigmented broiler eggs and non-pigmented white layer eggs. Monochromatic red light has been shown to improve hatchability in layer eggs. Therefore the objective of this study was to utilize one light fixture that emitted both white and monochromatic red light to determine if this one light source could improve hatchability in both types of chicken eggs and pigmented Pekin duck egg. To determine this, 3 experiments were conducted, the first using White Leghorn eggs (N = 6912), the second using commercial broiler eggs (N = 4608), and the third using commercial Pekin duck eggs (N = 3564) in which eggs were incubated with 12 h of light and 12 h of darkness (LED) or complete darkness (DARK); the light level was 250 lux. Hatchability, embryo mortality, and hatchling quality were measured. In Experiment 1, LED had fewer early dead embryos (P = 0.03), less overall embryo mortality (P = 0.05), fewer chicks with unhealed navels (P < 0.001), fewer chicks with defects (P < 0.001), and a higher percentage of fertile eggs that hatched (P = 0.05) than DARK. In Experiment 2, LED had fewer chicks with unhealed navels (P = 0.003), fewer chicks with defects (P = 0.001), and a higher percentage of fertile eggs that hatched (P = 0.04) than DARK. In Experiment 3, LED had fewer early dead embryos (P = 0.05), lower overall embryo mortality (P = 0.04), and a higher percentage of fertile eggs that hatched (P = 0.05), and had ducklings with lower bodyweights at hatch (P = 0.04) than DARK. These results indicate that providing both white and red light during incubation can improve chick quality across poultry varieties. This type of fixture could be used to improve commercial hatchery efficiency and chick quality. © 2017 Poultry Science Association Inc.

Effects of ascorbic acid enrichment by immersion of rainbow trout (Oncorhynchus mykiss, Walbaum 1792) eggs and embryos

USGS Publications Warehouse

Falahatkar, B.; Dabrowski, K.; Arslan, M.; Rinchard, J.

2006-01-01

This study was conducted to examine the effects of different forms and concentrations of ascorbic acid (vitamin C), and different enrichment times (24 and 48 h post ovulation) on egg, embryo and alevin ascorbate concentrations and survival of rainbow trout (enrichment was at the ova stage). In experiments 1 and 2, fertilized eggs were immersed in water containing ascorbate at 0 (control), 100, 1000 mg L-1 l-ascorbic acid (AA) and 2000 mg L -1 l-ascorbyl monophosphate (AP). In experiment 3, 0 (control), 500 and 1000 mg L-1 AA neutralized (N) with NaOH, 1000 mg L-1 AA non-neutralized (NN), 1000 and 2000 mg L-1 AP immersions were used. The mean total ascorbic acid (TAA) and dehydroascorbic acid (DHA) concentrations were measured before fertilization, at 3 and 24 h after fertilization, at the eyed stage, and in hatched alevins. We observed significant differences in TAA concentration at different immersion levels at 3 and 24 h after fertilization. Survival decreased significantly depending on the level of vitamin C, pH of the solutions and immersion time. We suggest that when broodstock rainbow trout do not have enough vitamin C in their ovaries, immersion of eggs in 1000 mg L-1 of neutralized AA may be useful. ?? 2006 Blackwell Publishing Ltd.

Cryptic choice of conspecific sperm controlled by the impact of ovarian fluid on sperm swimming behavior.

PubMed

Yeates, Sarah E; Diamond, Sian E; Einum, Sigurd; Emerson, Brent C; Holt, William V; Gage, Matthew J G

2013-12-01

Despite evidence that variation in male-female reproductive compatibility exists in many fertilization systems, identifying mechanisms of cryptic female choice at the gamete level has been a challenge. Here, under risks of genetic incompatibility through hybridization, we show how salmon and trout eggs promote fertilization by conspecific sperm. Using in vitro fertilization experiments that replicate the gametic microenvironment, we find complete interfertility between both species. However, if either species' ova were presented with equivalent numbers of both sperm types, conspecific sperm gained fertilization precedence. Surprisingly, the species' identity of the eggs did not explain this cryptic female choice, which instead was primarily controlled by conspecific ovarian fluid, a semiviscous, protein-rich solution that bathes the eggs and is released at spawning. Video analyses revealed that ovarian fluid doubled sperm motile life span and straightened swimming trajectory, behaviors allowing chemoattraction up a concentration gradient. To confirm chemoattraction, cell migration tests through membranes containing pores that approximated to the egg micropyle showed that conspecific ovarian fluid attracted many more spermatozoa through the membrane, compared with heterospecific fluid or water. These combined findings together identify how cryptic female choice can evolve at the gamete level and promote reproductive isolation, mediated by a specific chemoattractive influence of ovarian fluid on sperm swimming behavior. © 2013 The Authors. Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Cystic Fibrosis: Prenatal Screening and Diagnosis

MedlinePlus

... can use in vitro fertilization (IVF) with donor sperm or donor eggs (but the donor should be ... status). You can use IVF with your own sperm and eggs, and then use preimplantation genetic diagnosis ...

Causes of hatching failure in endangered birds

PubMed Central

Hemmings, N.; West, M.; Birkhead, T. R.

2012-01-01

About 10 per cent of birds' eggs fail to hatch, but the incidence of failure can be much higher in endangered species. Most studies fail to distinguish between infertility (due to a lack of sperm) and embryo mortality as the cause of hatching failure, yet doing so is crucial in order to understand the underlying problem. Using newly validated techniques to visualize sperm and embryonic tissue, we assessed the fertility status of unhatched eggs of five endangered species, including both wild and captive birds. All eggs were classified as ‘infertile’ when collected, but most were actually fertile with numerous sperm on the ovum. Eggs of captive birds had fewer sperm and were more likely to be infertile than those of wild birds. Our findings raise important questions regarding the management of captive breeding programmes. PMID:22977070

[The effect of palm oil and safflower oil in the feed of parent fattening hens on fertility, hatchability and growth of progeny].

PubMed

Halle, I

1999-01-01

The aim of two experiments with broiler breeder hens was to evaluate the effect of diets containing palm butter or safflower oil (25 g and 50 g/kg feed, resp.) on fertility, hatchability and growth of progeny. Especially the incorporation of oleic and linoleic acid in egg yolk reflected the dietary fatty acid source. Eggs were collected and stored in the incubator at a hen age of 31, 40, 50, and 60 weeks. Hatched chicks were reared over 5 weeks. The number of fertile eggs (Experiment 1 and 2, 75 and 88%, resp.) differed between the experiments (P < or = 0.05). Neither embryonic mortality nor hatchability (Experiment 1 and 2, 76 and 78%, resp.) were significantly affected by fatty acid composition of yolk. No clear maternal dietary effect was recorded on chicken weight at hatching (Experiment 1 and 2, 43.3 g and 43.7 g, resp.) and at 35 days of age (Experimental 1 and 2, 1676 g and 1764 g, resp.) The fatty acid composition in the analysed egg yolk sac of chicks showed a different fatty level but corresponded to fatty acid composition of breeding eggs before incubation. According to a decreased level of docosahexaenoic acid in egg yolk due to increased incorporation of linoleic acid, the content of this fatty acid was also diminished in phospholipids of the brain of chicken on days 1 and 5 after hatching.

Spawning Behavior and Egg Development of Aplysia kurodai Inhabiting the Coastal Waters of Jeju Island, Korea

PubMed Central

Lee, Chi-Hoon; Kaang, Bong-Kiun; Lee, Young-Don

2014-01-01

This study was investigated spawning behavior, structure of egg masses and egg development in Aplysia kurodai inhabiting the coastal waters of Jeju Island, Korea. The mating and courtship behavior of A. kurodai occurred in the form of unilateral copulating with chain formation. In chain copulation, only the first animal acted as a female; the second and succeeding animals acted as males (sperm donors) to the animals in front and as females to the animals behind. The fertilized eggs were packaged in capsules that are embedded in jelly to form a cylindrical string called an egg masses. The number of capsule per cm of the egg masses was 55 to 60 capsules and each capsule within the egg masses held 15 to 25 eggs. After spawning, the egg masses were bright yellow or orange in color. This egg masses color not changed until embryos developed into trochophore stage. Thereafter, as embryo developed from trochophore stage to veliger stage the egg masses color became brownish. The fertilized eggs were spherical, with a diameter of approximately 80±1 μm at spawning. At 5 to 6 days after spawning, the embryo developed into trochophore stage and began to rotate within the egg capsule. In the trochophore stage, the precursor of the velum, called the prototroch or prevelum, developed. At 10 days after spawning, the prevelum is transformed into the velum, and the trochophore developed into veliger stage. Between 10 to 15 days after spawning, the veligers broke out of the egg capsule, and hatched as free-swimming larvae. PMID:25949168

Evaluation of cryoprotective effect of Turkish pine honey on common carp (Cyprinus carpio) spermatozoa.

PubMed

Ogretmen, F; Inanan, B E

2014-01-01

The cryopreservation procedures that allow preserving sperm cells have been applied for sperm of many species. A sugar like glucose, fructose and sucrose were frequently used in cryomedia but up to the present pine honey was not used for cryopreservation of sperm cells. The objective of present study is to investigate the effect of pine honey in various concentrations of 100, 200, 300, 400 and 500 mg/ml solutions on cryopreservation and fertilization ability of spermatozoa of common carp (Cyprinus carpio). Totally 12.5 % (v/v) Me2SO as a cryoprotectant and 10 % (v/v) egg yolk added all extenders. Pine honey also compared with sugars as glucose, fructose (monosaccharide) and sucrose (disaccharide). Collected semen samples were diluted at the ratio of 1:9 with the extenders. After dilutions, the sperm motility was assessed for each group and then the diluted semen samples were cryopreserved. The extenders containing 300 mg ml-1 pine honey group showed both highest post thaw motility 75.3 ± 5.1 %, motility duration (s) 47.3 ± 2.5 % and hatching ratio 42.6 ± 4.2 % than other cryopreserved groups (P<0.05). Using the pine honey in cryomedia is effective for cryopreservation especially about hatching success of egg fertilized by frozen-thawed sperm of common carp.

In Vitro Fertilization (IVF)

MedlinePlus

... or eggs are implanted in your uterus. One cycle of IVF takes about two weeks. IVF is ... Specific steps of an in vitro fertilization (IVF) cycle carry risks, including: Multiple births. IVF increases the ...

Estimate the contribution of incubation parameters influence egg hatchability using multiple linear regression analysis

PubMed Central

Khalil, Mohamed H.; Shebl, Mostafa K.; Kosba, Mohamed A.; El-Sabrout, Karim; Zaki, Nesma

2016-01-01

Aim: This research was conducted to determine the most affecting parameters on hatchability of indigenous and improved local chickens’ eggs. Materials and Methods: Five parameters were studied (fertility, early and late embryonic mortalities, shape index, egg weight, and egg weight loss) on four strains, namely Fayoumi, Alexandria, Matrouh, and Montazah. Multiple linear regression was performed on the studied parameters to determine the most influencing one on hatchability. Results: The results showed significant differences in commercial and scientific hatchability among strains. Alexandria strain has the highest significant commercial hatchability (80.70%). Regarding the studied strains, highly significant differences in hatching chick weight among strains were observed. Using multiple linear regression analysis, fertility made the greatest percent contribution (71.31%) to hatchability, and the lowest percent contributions were made by shape index and egg weight loss. Conclusion: A prediction of hatchability using multiple regression analysis could be a good tool to improve hatchability percentage in chickens. PMID:27651666

Present-day nearshore pH differentially depresses fertilization in congeneric sea urchins.

PubMed

Frieder, Christina A

2014-02-01

Ocean acidification impacts fertilization in some species of sea urchin, but whether sensitivity is great enough to be influenced by present-day pH variability has not been documented. In this study, fertilization in two congeneric sea urchins, Strongylocentrotus purpuratus and S. franciscanus, was found to be sensitive to reduced pH, <7.50, but only within a range of sperm-egg ratios that was species-specific. By further testing fertilization across a broad range of pH, pH-fertilization curves were generated and revealed that S. purpuratus was largely robust to pH, while fertilization in S. franciscanus was sensitive to even modest reductions in pH. Combining the pH-fertilization response curves with pH data collected from these species' habitat demonstrated that relative fertilization success remained high for S. purpuratus but could be as low as 79% for S. franciscanus during periods of naturally low pH. In order for S. franciscanus to maintain high fertilization success in the present and future, adequate adult densities, and thus sufficient sperm-egg ratios, will be required to negate the effects of low pH. In contrast, fertilization of S. purpuratus was robust to a broad range of pH, encompassing both present-day and future ocean acidification scenarios, even though the two congeners have similar habitats.

Calcium and Egg Activation in Drosophila

PubMed Central

Sartain, Caroline V.; Wolfner, Mariana F.

2012-01-01

Summary In many animals, a rise in intracellular calcium levels is the trigger for egg activation, the process by which an arrested mature oocyte transitions to prepare for embryogenesis. In nearly all animals studied to date, this calcium rise, and thus egg activation, is triggered by the fertilizing sperm. However in the insects that have been examined, fertilization is not necessary to activate their oocytes. Rather, these insects’ eggs activate as they transit through the female’s reproductive tract, regardless of male contribution. Recent studies in Drosophila have shown that egg activation nevertheless requires calcium and that the downstream events and molecules of egg activation are also conserved, despite the difference in initial trigger. Genetic studies have uncovered essential roles for the calcium-dependent enzyme calcineurin and its regulator calcipressin, and have hinted at roles for calmodulin, in Drosophila egg activation. Physiological and in vitro studies have led to a model in which mechanical forces that impact the Drosophila oocyte as it moves through the reproductive tract triggers the influx of calcium from the external environment, thereby initiating egg activation. Future research will aim to test this model, as well as to determine the spatiotemporal dynamics of cytoplasmic calcium flux and mode of signal propagation in this unique system. PMID:23218670

Regulator of G-protein signaling 2 (RGS2) suppresses premature calcium release in mouse eggs

PubMed Central

Bernhardt, Miranda L.; Lowther, Katie M.; Padilla-Banks, Elizabeth; McDonough, Caitlin E.; Lee, Katherine N.; Evsikov, Alexei V.; Uliasz, Tracy F.; Chidiac, Peter; Williams, Carmen J.; Mehlmann, Lisa M.

2015-01-01

During oocyte maturation, capacity and sensitivity of Ca2+ signaling machinery increases dramatically, preparing the metaphase II (MII)-arrested egg for fertilization. Upon sperm-egg fusion, Ca2+ release from IP3-sensitive endoplasmic reticulum stores results in cytoplasmic Ca2+ oscillations that drive egg activation and initiate early embryo development. Premature Ca2+ release can cause parthenogenetic activation prior to fertilization; thus, preventing inappropriate Ca2+ signaling is crucial for ensuring robust MII arrest. Here, we show that regulator of G-protein signaling 2 (RGS2) suppresses Ca2+ release in MII eggs. Rgs2 mRNA was recruited for translation during oocyte maturation, resulting in ∼20-fold more RGS2 protein in MII eggs than in fully grown immature oocytes. Rgs2-siRNA-injected oocytes matured to MII; however, they had increased sensitivity to low pH and acetylcholine (ACh), which caused inappropriate Ca2+ release and premature egg activation. When matured in vitro, RGS2-depleted eggs underwent spontaneous Ca2+ increases that were sufficient to cause premature zona pellucida conversion. Rgs2−/− females had reduced litter sizes, and their eggs had increased sensitivity to low pH and ACh. Rgs2−/− eggs also underwent premature zona pellucida conversion in vivo. These findings indicate that RGS2 functions as a brake to suppress premature Ca2+ release in eggs that are poised on the brink of development. PMID:26160904

In vitro evidence for the participation of Drosophila melanogaster sperm β-N-acetylglucosaminidases in the interactions with glycans carrying terminal N-acetylglucosamine residues on the egg's envelopes.

PubMed

Intra, Jari; Veltri, Concetta; De Caro, Daniela; Perotti, Maria Elisa; Pasini, Maria Enrica

2017-09-01

Fertilization is a complex and multiphasic process, consisting of several steps, where egg-coating envelope's glycoproteins and sperm surface receptors play a critical role. Sperm-associated β-N-acetylglucosaminidases, also known as hexosaminidases, have been identified in a variety of organisms. Previously, two isoforms of hexosaminidases, named here DmHEXA and DmHEXB, were found as intrinsic proteins in the sperm plasma membrane of Drosophila melanogaster. In the present work, we carried out different approaches using solid-phase assays in order to analyze the oligosaccharide recognition ability of D. melanogaster sperm hexosaminidases to interact with well-defined carbohydrate chains that might functionally mimic egg glycoconjugates. Our results showed that Drosophila hexosaminidases prefer glycans carrying terminal β-N-acetylglucosamine, but not core β-N-acetylglucosamine residues. The capacity of sperm β-N-acetylhexosaminidases to bind micropylar chorion and vitelline envelope was examined in vitro assays. Binding was completely blocked when β-N-acetylhexosaminidases were preincubated with the glycoproteins ovalbumin and transferrin, and the monosaccharide β-N-acetylglucosamine. Overall, these data support the hypothesis of the potential role of these glycosidases in sperm-egg interactions in Drosophila. © 2017 Wiley Periodicals, Inc.

Effects of different storage time on hatching results and some egg quality characteristics of rock partridge (A. graeca) (management and production).

PubMed

Günhan, S; Kirikçi, K

2017-06-01

In this research, partridge eggs were stored during zero to 7, 8 to 14, 15 to 21, 22 to 28, 29 to 35 and 36 to 42 d, respectively. The effect of different egg storage periods on egg protein and moisture rates, mineral contents, and some egg quality and hatching characteristics were investigated. The extension of egg storage times didn't affect the external quality features like shell weight, shell thickness, and albumen rate, but it affected the yolk weight, yolk index, albumen index, and Haugh unit (P < 0.05). Yolk weight was increased and yolk index, albumen index, and Haugh unit values were decreased with the extension of storage time. Different storage times of partridge eggs did not have important effects on the protein rates. Protein and humidity rate of the eggs were 14.21 and 67.64%, respectively. There were some elements such as S, P, Na, K, and Ca, but Al, Cd, Co, Mo, and Pb could not be found in the partridge eggs. There is no effect of the storage time on the mineral content of the egg. Storage time had negative effect on fertility and hatchability after 21 d of storage d, but no effect on hatchability of fertile eggs. As this study showed, partridge eggs are resistant to long storage times, as partridge egg proteins can resist degradation in the optimum storage times. To determine egg degradation, the study should be focused on partridge eggshell features, which are responsible for degradation. As a result of this research, partridge eggs can be stored for 21 d under optimum storage conditions without any negative hatchability results. © 2017 Poultry Science Association Inc.

Embryogenic plant cells in microgravity

NASA Technical Reports Server (NTRS)

Krikorian, Abraham D.

1991-01-01

In view of circumstantial evidence for the role of gravity (g) in shaping the embryo environment, normal embryo development may not occur reliably and efficiently in the microgravity environment of space. Attention must accordingly be given to those aspects of higher plant reproductive biology in space environments required for the production of viable embryos in a 'seed to seed to seed' experiment. It is suggested that cultured cells can be grown to be morphogenetically competent, and can be evaluated as to their ability to simulate embryogenic events usually associated with fertilized eggs in the embryo sac of the ovule in the ovary.

Comparing sugar type supplementation for cryopreservation of boar semen in egg yolk based extender.

PubMed

Malo, C; Gil, L; Gonzalez, N; Cano, R; de Blas, I; Espinosa, E

2010-08-01

Cryopreservation of boar semen is still considered suboptimal due to lower fertility when compared to fresh semen. The aim of this study was to evaluate the effects of the addition of different sugars (lactose, trehalose and glucose) on boar spermatozoa cryopreserved in an egg yolk based extender. Ejaculates were collected from a boar previously selected and semen samples were processed using the straw freezing procedure. In experiment 1, subsamples of semen were frozen in three different extenders: recommended lactose egg yolk extender (LEY); trehalose egg yolk extender (TEY) and glucose egg yolk extender (GEY). Sperm quality was assessed for motility, viability, acrosome integrity and hypoosmotic swelling test response upon collection, after freezing and thawing and then every hour for 3h. Results showed that total motility at 1 and 3h, progressive motility at 3h, positive hypoosmotic response at 2 and 3h and acrosome integrity at all times were significantly improved when trehalose was added to the extender. In experiment 2, sugar influence was also demonstrated in vitro fertilization. A total of 1691 oocytes were in vitro matured and inseminated with frozen-thawed sperm at 2000:1 sperm:oocyte ratio and coincubated for 6h. Presumptive zygotes were cultured in NCSU-23 medium to assess fertilization parameters and embryo development. Both penetration and monospermy rates were significantly higher for trehalose frozen semen. A significant increase was observed in efficiency and blastocyst formation rates from TEY to the other groups. Our results demonstrated that trehalose extender enhances spermatozoa viability and its in vitro fertilization parameters in boar ejaculates with good sperm freezability. Further studies are necessary to assess the impact of sugars on the entire population. (c) 2010 Elsevier Inc. All rights reserved.

Identification of a novel C1q family member in color crucian carp (Carassius auratus) ovary.

PubMed

Chen, Bo; Gui, Jianfang

2004-07-01

Potential roles of C1q/tumor necrosis factor (TNF) superfamily proteins have been observed in vertebrate oogenesis and oocyte maturation, but no ovary-specific member has been identified so far. In this study, we have cloned and identified a novel member of C1q family with a C1q domain in the C-terminal from fully grown oocyte cDNA library of color crucian carp and demonstrated that the gene might be specifically expressed in ovary and therefore designated as Carassius auratus ovary-specific C1q-like factor, CaOC1q-like factor. It encodes a 213 amino acid protein with a 17 amino acid signal peptide. There is only one protein band of about 24.5 kDa in the extracts from phase I to phase IV oocytes, but two positive protein bands are detected in the extracts of mature eggs and fertilized eggs. Furthermore, the mobility shift of the smaller target protein band cannot be eliminated by phosphatase treatment, but the larger protein band increases its mobility on the gel after phosphatase treatment, suggesting that the larger protein might be a phosphorylated form. Immunofluorescence localization indicates that the CaOC1q-like proteins localize in cytoplasm, cytoplasm membrane and egg envelope of the oocytes at cortical granule stage and vitellogenesis stage, whereas they were compressed to cytoplasm margin in ovulated mature eggs and discharged into perivitelline space between cytoplasm membrane and egg envelope after egg fertilization. Further studies on distribution and translocation mechanism of the CaOC1q-like factor will be benefit to elucidate the unique function in oogenesis, oocyte maturation and egg fertilization.

Trust women to choose: a response to John a Robertson's ‘Egg freezing and Egg banking: empowerment and alienation in assisted reproduction’†

PubMed Central

2017-01-01

Abstract In ‘Egg Freezing and Egg Banking: Empowerment and Alienation in Assisted Reproduction’, John A Robertson responds to the American Society of Reproductive Medicine's statement that oocyte preservation should no longer be considered an experimental treatment. He explores the implications of this development, focusing on the potentially empowering impact of oocyte preservation as a means for women to preserve their fertility. He also engages with concerns about the possibility that such a development may raise issues of alienation. He highlights some of the potential problems that may emerge as women gain the capacity to store and either donate or sell any eggs they do not need for their own reproductive purposes. Much of his paper is valuable and considered, but in places, his views rest on assumptions about women's attitudes to their fertility, understanding of the technology, and relationship with their gametes that are open to dispute. This paper teases out some of these assumptions and puts pressure on them by drawing on the growing body of data about what women actually do think and feel about fertility issues. It focuses on two of his main concerns—that social egg freezing may give women a false sense of security and that women may be harmed if a market in eggs leads to their alienation from their gametes. Via this response to Robertson, I aim to redress the tendency often seen in discussions around women, infertility, aging, and empowerment to unquestioningly accept what I argue are stereotypes and assumptions about women's views and capacity to reason. PMID:29868183

Systematic Mapping and Functional Analysis of a Family of Human Epididymal Secretory Sperm-Located Proteins*

PubMed Central

Li, JianYuan; Liu, FuJun; Wang, HaiYan; Liu, Xin; Liu, Juan; Li, Ning; Wan, FengChun; Wang, WenTing; Zhang, ChengLin; Jin, ShaoHua; Liu, Jie; Zhu, Peng; Liu, YunXiang

2010-01-01

The mammalian spermatozoon has many cellular compartments, such as head and tail, permitting it to interact with the female reproductive tract and fertilize the egg. It acquires this fertilizing potential during transit through the epididymis, which secretes proteins that coat different sperm domains. Optimal levels of these proteins provide the spermatozoon with its ability to move to, bind to, fuse with, and penetrate the egg; otherwise male infertility results. As few human epididymal proteins have been characterized, this work was performed to generate a database of human epididymal sperm-located proteins involved in maturation. Two-dimensional gel electrophoresis of epididymal tissue and luminal fluid proteins, followed by identification using MALDI-TOF/MS or MALDI-TOF/TOF, revealed over a thousand spots in gels comprising 745 abundant nonstructural proteins, 408 in luminal fluids, of which 207 were present on spermatozoa. Antibodies raised to 619 recombinant or synthetic peptides, used in Western blots, histological sections, and washed sperm preparations to confirm antibody quality and protein expression, indicated their regional location in the epididymal epithelium and highly specific locations on washed functional spermatozoa. Sperm function tests suggested the role of some proteins in motility and protection against oxidative attack. A large database of these proteins, characterized by size, pI, chromosomal location, and function, was given a unified terminology reflecting their sperm domain location. These novel, secreted human epididymal proteins are potential targets for a posttesticular contraceptive acting to provide rapid, reversible, functional sterility in men and they are also biomarkers that could be used in noninvasive assessments of male fertility. PMID:20736409

Termite queens close the sperm gates of eggs to switch from sexual to asexual reproduction.

PubMed

Yashiro, Toshihisa; Matsuura, Kenji

2014-12-02

Males and females are in conflict over genetic transmission in the evolution of parthenogenesis, because it enhances female reproductive output but deprives the males' genetic contribution. For males, any trait that coerces females into sexual reproduction should increase their fitness. However, in the termite Reticulitermes speratus, queens produce their replacements (neotenic queens) parthenogenetically while using normal sexual reproduction to produce other colony members. Here, we show that termite queens produce parthenogenetic offspring in the presence of kings by closing the micropyles (sperm gates; i.e., openings for sperm entry) of their eggs. Our field survey showed that termite eggs show large variation in numbers of micropyles, with some having none. Microsatellite analysis showed that embryos of micropyleless eggs develop parthenogenetically, whereas those of eggs with micropyles are fertilized and develop sexually. Surveys of eggs among queens of different age groups showed that queens begin to lay micropyleless eggs when they are older and thus, need to produce their replacements parthenogenetically. In addition, we found clear seasonality in new neotenic queen differentiation and micropyleless egg production. This micropyle-dependent parthenogenesis is the first identification, to our knowledge, of the mechanism through which females control egg fertilization over time in diploid animals, implying a novel route of the evolution of parthenogenesis in favor of female interests without interference from males.

Ultrastructural dynamics of human reproduction, from ovulation to fertilization and early embryo development.

PubMed

Familiari, Giuseppe; Heyn, Rosemarie; Relucenti, Michela; Nottola, Stefania A; Sathananthan, A Henry

2006-01-01

This study describes the updated, fine structure of human gametes, the human fertilization process, and human embryos, mainly derived from assisted reproductive technology (ART). As clearly shown, the ultrastructure of human reproduction is a peculiar multistep process, which differs in part from that of other mammalian models, having some unique features. Particular attention has been devoted to the (1) sperm ultrastructure, likely "Tygerberg (Kruger) strict morphology criteria"; (2) mature oocyte, in which the MII spindle is barrel shaped, anastral, and lacking centrioles; (3) three-dimensional microarchitecture of the zona pellucida with its unique supramolecular filamentous organization; (4) sperm-egg interactions with the peculiarity of the sperm centrosome that activates the egg and organizes the sperm aster and mitotic spindles of the embryo; and (5) presence of viable cumulus cells whose metabolic activity is closely related to egg and embryo behavior in in vitro as well as in vivo conditions, in a sort of extraovarian "microfollicular unit." Even if the ultrastructural morphodynamic features of human fertilization are well understood, our knowledge about in vivo fertilization is still very limited and the complex sequence of in vivo biological steps involved in human reproduction is only partially reproduced in current ART procedures.

[Controlling effect of antagonist bioorganic fertilizer on tomato root-knot nematode].

PubMed

Zhu, Zhen; Chen, Fang; Xiao, Tong-jian; Wang, Xiao-hui; Ran, Wei; Yang, Xing-ming; Shen, Qi-rong

2011-04-01

Indoor in vitro culture experiment and greenhouse pot experiment were conducted to evaluate the capabilities of three bacterial strains XZ-173 (Bacillus amyloliquefaciens), SL-25 (B. gibsonii), and KS-62 (Paenibacillus polymyxa) that can hydrolyze collagen protein in controlling tomato root-knot nematode. In the in vitro culture experiment, suspensions of XZ-173, SL-25, and KS-62 induced a mortality rate of 75.9%, 66.7%, and 50.0% to the second-stage junior nematode within 24 h, and decreased the egg hatching rate to 17.8%, 28.9% and 37.6% after 7-day incubation, respectively, in contrast to the 17.4% mortality rate and 53.6% egg hatching rate in the control (sterilized water). In the greenhouse pot experiment, the bioorganic fertilizer mixed with equal parts of fermented XZ-173, SL-25, and KS-62 gained the best result, with the root-knot nematode population in rhizosphere soil decreased by 84.0% as compared with the control. The bioorganic fertilizer also decreased the numbers of galls and eggs on tomato roots significantly, and increased the underground and aboveground biomass of tomato. Therefore, antagonist bioorganic fertilizer has promising potential in controlling root-knot nematode.

Structural analysis of fertilization in the fish Brycon orbignyanus.

PubMed

Ganeco, Luciana Nakaghi; Franceschini-Vicentini, Irene Bastos; Nakaghi, Laura Satiko Okada

2009-05-01

In the present work, we analyzed the structure of oocytes and fertilized eggs of the piracanjuba fish (Brycon orbignyanus) under light and scanning electron microscopy. After inducing spawning, samples were collected at the moment of oocyte extrusion, when oocytes and semen were mixed (time 0), as well as at 10, 20 and 30 s after mixing, every minute up to 10 min, and then at 15 and 20 min. The oocytes are spherical, translucent and greenish with a mean diameter of 1.3 +/- 0.11 mm. During the extrusion, cytoplasmic movement was observed in eggs towards the micropyle, characterizing the animal pole. At the moment of fertilization, the cortical cytoplasm showed a higher concentration of cortical alveoli at the animal pole than at the vegetal pole. The cortical alveoli breakdown promoted the elevation of the chorion with a consequent increase in egg diameter (1.95 +/- 0.08 mm). The penetration of the spermatozoon promotes the formation of a fertilization cone of spherical external structure, which obstructs the opening of the micropyle. This structure acts as a main mechanism to avoid polyspermy, intercepting the access of supernumerary spermatozoa. Such studies about the reproductive biology of fish are important to species survival and conservation programmes.

Fertilization of frog eggs on a Sounding Rocket in space.

PubMed

Ubbels, G A; Berendsen, W; Narraway, J

1989-01-01

During the TEXUS-17 flight (April/May 1988) eggs of a higher organism, the anuran amphibian Xenopus laevis, have for the first time been successfully fertilized under microgravity on a Sounding Rocket. This result also implies that Life Sciences Experiments of Short Duration can be carried out on Sounding Rockets. The latter can therefore function as additional carriers for such experiments. Histological sections of the experimental material demonstrated the penetration of sperm into eggs, while SEM analysis revealed the differentiation of characteristic egg surface structures. Our TEXUS-17 experiment convincingly shows that the modified automatic experiment container, originally designed for experimental BR 52NL on the D1-mission, now functions flawlessly. Eight containers were flown in an airtight, well-isolated box (TEM 06-15), and a similar set was activated on Earth, two hours later. The analysis of the biological material is in progress.

Making families: organizational boundary work in US egg and sperm donation.

PubMed

Johnson, Katherine M

2013-12-01

Egg and sperm donation can create distinct issues for designating family boundaries. These issues come to the forefront as relations between donors, recipients, and donor-conceived children have been shifting from anonymous to more open arrangements in the US and other western countries. In this study, I address US organizational practices and family boundary construction. Fertility clinics, egg donation agencies, and sperm banks are central providers of US gamete donation services. Given the disruptive potential of gamete donation, how do they manage relationships between parties? Through a content analysis of materials from twenty fertility clinics, twenty egg donation agencies, and thirty-one sperm banks, I address three major strategies of organizational boundary work: 1) creating identity categories, 2) managing information, and 3) managing interaction. I ultimately argue that even as many organizations offer opportunities for connections between parties, they exercise social control over donation arrangements through bounded relationships. Copyright © 2013 Elsevier Ltd. All rights reserved.

Quantitative mapping of zinc fluxes in the mammalian egg reveals the origin of fertilization-induced zinc sparks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Que, Emily L.; Bleher, Reiner; Duncan, Francesca E.

2014-12-15

Fertilization of a mammalian egg initiates a series of 'zinc sparks' that are necessary to induce the egg-to-embryo transition. Despite the importance of these zinc-efflux events little is known about their origin. To understand the molecular mechanism of the zinc spark we combined four physical approaches that resolve zinc distributions in single cells: a chemical probe for dynamic live-cell fluorescence imaging and a combination of scanning transmission electron microscopy with energy-dispersive spectroscopy, X-ray fluorescence microscopy and three-dimensional elemental tomography for high-resolution elemental mapping. We show that the zinc spark arises from a system of thousands of zinc-loaded vesicles, each ofmore » which contains, on average, 10(6) zinc atoms. These vesicles undergo dynamic movement during oocyte maturation and exocytosis at the time of fertilization. The discovery of these vesicles and the demonstration that zinc sparks originate from them provides a quantitative framework for understanding how zinc fluxes regulate cellular processes« less

Quantitative mapping of zinc fluxes in the mammalian egg reveals the origin of fertilization-induced zinc sparks.

PubMed

Que, Emily L; Bleher, Reiner; Duncan, Francesca E; Kong, Betty Y; Gleber, Sophie C; Vogt, Stefan; Chen, Si; Garwin, Seth A; Bayer, Amanda R; Dravid, Vinayak P; Woodruff, Teresa K; O'Halloran, Thomas V

2015-02-01

Fertilization of a mammalian egg initiates a series of 'zinc sparks' that are necessary to induce the egg-to-embryo transition. Despite the importance of these zinc-efflux events little is known about their origin. To understand the molecular mechanism of the zinc spark we combined four physical approaches that resolve zinc distributions in single cells: a chemical probe for dynamic live-cell fluorescence imaging and a combination of scanning transmission electron microscopy with energy-dispersive spectroscopy, X-ray fluorescence microscopy and three-dimensional elemental tomography for high-resolution elemental mapping. We show that the zinc spark arises from a system of thousands of zinc-loaded vesicles, each of which contains, on average, 10(6) zinc atoms. These vesicles undergo dynamic movement during oocyte maturation and exocytosis at the time of fertilization. The discovery of these vesicles and the demonstration that zinc sparks originate from them provides a quantitative framework for understanding how zinc fluxes regulate cellular processes.

Early development of the longsnout seahorse Hippocampus reidi (Syngnathidae) within the male brood pouch.

PubMed

Novelli, B; Otero Ferrer, F; Socorro, J A; Molina Domínguez, L

2018-06-01

Fertilized and unfertilized eggs and embryos of the longsnout seahorse Hippocampus reidi were collected at different stages of development and provided the basis for a description of morphological development from fertilization until release from the paternal pouch. Images of fertilized eggs, as well as their rupture after a few minutes in seawater are reported for the first time. The yolk sac transitioned from ovoid to spherical shape and was reabsorbed progressively until release. The tail began rising from the surface of the deuteroplasm while embryos were in the egg envelope. Embryos lacked a primordial fin fold and developed some species characteristics, such as rays in the dorsal fin, before resorption of the yolk sac. At release, juvenile seahorses were in an advanced stage of development even if they lacked important adult characteristics, such as ring plates and coronet. The tail was not prehensile in juveniles at release; a small caudal fin was present, although this fin is lost in adults. © 2018 The Fisheries Society of the British Isles.

Quantitative mapping of zinc fluxes in the mammalian egg reveals the origin of fertilization-induced zinc sparks

PubMed Central

Que, Emily L.; Bleher, Reiner; Duncan, Francesca E.; Kong, Betty Y.; Gleber, Sophie C.; Vogt, Stefan; Chen, Si; Garwin, Seth A.; Bayer, Amanda R.; Dravid, Vinayak; Woodruff, Teresa K.; O’Halloran, Thomas V.

2015-01-01

Fertilization of a mammalian egg induces a series of ‘zinc sparks’ that are necessary for inducing the egg-to-embryo transition. Despite the importance of these zinc efflux events little is known about their origin. To understand the molecular mechanism of the zinc spark we combined four physical approaches to resolve zinc distributions in single cells: a chemical probe for dynamic live-cell fluorescence imaging and a combination of scanning transmission electron microscopy with energy dispersive spectroscopy, X-ray fluorescence microscopy, and 3D elemental tomography for high resolution elemental mapping. We show that the zinc spark arises from a system of thousands of zinc-loaded vesicles, each of which contains, on average, 106 zinc atoms. These vesicles undergo dynamic movement during oocyte maturation and exocytosis at the time of fertilization. The discovery of these vesicles and the demonstration that zinc sparks originate from them provides a quantitative framework for understanding how zinc fluxes regulate cellular processes. PMID:25615666

Examining the relationships between egg cortisol and oxidative stress in developing wild sockeye salmon (Oncorhynchus nerka).

PubMed

Taylor, Jessica J; Sopinka, Natalie M; Wilson, Samantha M; Hinch, Scott G; Patterson, David A; Cooke, Steven J; Willmore, William G

2016-10-01

Maternally-derived hormones in oocytes, such as glucocorticoids (GCs), play a crucial role in embryo development in oviparous taxa. In fishes, maternal stressor exposure increases circulating and egg cortisol levels, the primary GC in fishes, as well as induces oxidative stress. Elevated egg cortisol levels modify offspring traits but whether maternal oxidative stress correlates with circulating and egg cortisol levels, and whether maternal/egg cortisol levels correlate with offspring oxidative stress have yet to be determined. The objective of this study was to examine the relationships among maternal and egg cortisol, and maternal and offspring oxidative stress to provide insight into the potential intergenerational effects of stressor exposure in sockeye salmon (Oncorhynchus nerka). Antioxidant concentration and oxidative stress were measured in maternal tissues (plasma, brain, heart and liver) as well as offspring developmental stages (pre-fertilization, 24h post-fertilization, eyed, and hatch), and were compared to both naturally-occurring and experimentally-elevated (via cortisol egg bath) levels of cortisol in eggs. Oxygen radical absorptive capacity of tissues from maternal sockeye salmon was measured spectrophotometrically and was not correlated with maternal or egg cortisol concentrations. Also, naturally-occurring and experimentally-elevated cortisol levels in eggs (to mimic maternal stress) did not affect oxidative stress or antioxidant capacity of the offspring. We conclude that the metrics of maternal stress examined in sockeye salmon (i.e., maternal/egg cortisol, maternal oxidative stress) are independent of each other, and that egg cortisol content does not influence offspring oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of water hardness on size and hatching success of silver carp eggs

USGS Publications Warehouse

Rach, Jeff J.; Sass, Greg G.; Luoma, James A.; Gaikowski, Mark P.

2010-01-01

Eggs of silver carp Hypophthalmichthys molitrix absorb water after release from the female, causing them to become turgid and to increase substantially in size. The volume of water that diffuses within an egg is most likely determined by (1) the difference in ionic concentration between the egg and the water that surrounds it and (2) the elasticity of the egg membrane. Prior observations suggest that silver carp eggs may swell and burst in soft waters. If water hardness affects silver carp reproductive success in nonnative ecosystems, this abiotic factor could limit silver carp distribution or abundance. In this study, we tested the effect of water hardness on silver carp egg enlargement and hatching success. Groups of newly fertilized silver carp eggs were placed in water at one of five nominal water hardness levels (50, 100, 150, 200, or 250 mg/L as CaCO3) for 1 h to harden (absorb water after fertilization). Egg groups were then placed in separate incubation vessels housed in two recirculation systems that were supplied with either soft (50 mg/L as CaCO3) or hard (250 mg/L as CaCO3) water to evaluate hatching success. Tests were terminated within 24 h after viable eggs had hatched. Eggs that were initially placed in 50-mg/L water to harden were larger (i.e., swelled more) and had a greater probability of hatch than eggs hardened in other water hardness levels. Unlike the effect of water hardness during egg hardening, the water hardness during incubation appeared to have no effect on egg hatching success. Our research suggests that water hardness may not be a limiting factor in the reproduction, recruitment, and range expansion of silver carp in North America.

Practical evolution and application of direct intracytoplasmic sperm injection for male factor and idiopathic fertilization failure infertilities.

PubMed

Tucker, M J; Wright, G; Morton, P C; Mayer, M P; Ingargiola, P E; Jones, A E

1995-04-01

To analyze the introduction of a new assisted fertilization technique for the treatment of severe male factor and idiopathic fertilization failure infertilities. Retrospective analysis of 16-month clinical application of IVF-ET where insemination was performed solely by direct intracytoplasmic sperm injection. Clinical IVF-ET program. Ninety-two couples undergoing 105 cycles of sperm injection. One hundred embryo transfers yielded 28 viable pregnancies (28%) from which eight normal deliveries have occurred to date. Complete cleavage arrest or fertilization failure occurred in four cycles, and one couple had all embryos cryopreserved. One thousand one hundred forty-three eggs were injected of which 173 (15%) degenerated. Four hundred seventy-nine of the surviving 970 eggs became normally fertilized (49%), and 381 of these zygotes (79.5%) developed suitably for cryopreservation or for transfer. Thirty-four of 310 embryos transferred implanted, yielding an implantation rate of 11%. Both testicular and epididymal sperm were used successfully to achieve fertilization and pregnancies, as was sperm retrieved by electroejaculation. Older women and couples suffering from prior idiopathic fertilization failure had a markedly poorer outcome. These results confirm that the intracytoplasmic sperm injection technique is a successful form of assisted fertilization that can be applied to a wide range of couples at significant risk from fertilization failure.

[Mg2+]o/[Ca2+]o determines Ca2+ response at fertilization: tuning of adult phenotype?

PubMed

Ozil, Jean-Pierre; Sainte-Beuve, Thierry; Banrezes, Bernadette

2017-11-01

Alteration of the postnatal phenotype has sparked great concern about the developmental impact of culture media used at fertilization. However, the mechanisms and compounds involved are yet to be determined. Here, we used the Ca 2+ responses from mouse eggs fertilized by ICSI as a dynamic and quantitative marker to understand the role of compounds in egg functioning and establish possible correlations with adult phenotypes. We computed 134 Ca 2+ responses from the first to the last oscillation in media with specific formulations. Analyses demonstrate that eggs generated two times as many Ca 2+ oscillations in KSOM as in M16 media (18.8 ± 7.0 vs 9.2 ± 2.5). Moreover, the time increment of the delay between two consecutive oscillations, named TIbO, is the most sensitive coefficient characterizing the mechanism that paces Ca 2+ oscillations once the egg has been fertilized. Neither doubling external free Ca 2+ nor dispermic fertilization increased significantly the total number of Ca 2+ oscillations. In contrast, removing Mg 2+ from the M16 boosted Ca 2+ oscillations to 54.0 ± 35.2. Hence, [Mg 2+ ] o /[Ca 2+ ] o appears to determine the number, duration and frequency of the Ca 2+ oscillations. These changes were correlated with long-term effects. The rate of female's growth was impacted with the 'KSOM' females having only half the fat deposit of 'M16' females. Moreover, adult animals issued from M16 had significantly smaller brain weight vs 'KSOM' and 'control' animals. TIbO is a new Ca 2+ coefficient that gauges the very early functional impact of culture media. It offers the possibility of establishing correlations with postnatal consequences according to IVF medium formulation.Free French abstract: A French translation of this abstract is freely available at http://www.reproduction-online.org/content/154/5/675/suppl/DC2. © 2017 Society for Reproduction and Fertility.

Recombinant mouse sperm ZP3-binding protein (ZP3R/sp56) forms a high order oligomer that binds eggs and inhibits mouse fertilization in vitro.

PubMed

Buffone, Mariano G; Zhuang, Tiangang; Ord, Teri S; Hui, Ling; Moss, Stuart B; Gerton, George L

2008-05-02

Many candidates have been proposed as zona pellucida-binding proteins. Without precluding a role for any of those candidates, we focused on mouse sperm protein ZP3R/sp56, which is localized in the acrosomal matrix. The objective of this study was to analyze the role of ZP3R/sp56 in mouse fertilization. We expressed recombinant ZP3R/sp56 as a secreted protein in HEK293 cells and purified it from serum-free, conditioned medium. In the presence of reducing agents, the recombinant ZP3R/sp56 exhibited a molecular weight similar to that observed for the native ZP3R/sp56. Reminiscent of the native protein, recombinant ZP3R/sp56 formed a high molecular weight, disulfide cross-linked oligomer consisting of six or more monomers under non-reducing conditions. Recombinant ZP3R/sp56 bound to the zona pellucida of unfertilized eggs but not to 2-cell embryos, indicating that the changes that take place in the zona pellucida at fertilization affected the interaction of this protein with the zona pellucida. The extent of in vitro fertilization was reduced in a dose-dependent manner when unfertilized eggs were preincubated with recombinant ZP3R/sp56 (74% drop at the maximum concentrations assayed). Eggs incubated with the recombinant protein showed an absence of or very few sperm in the perivitelline space, suggesting that the reduction in the fertilization rate is caused by the inhibition of sperm binding and/or penetration through the zona pellucida. These results indicate that sperm ZP3R/sp56 is important for sperm-zona interactions during fertilization and support the concept that the acrosomal matrix plays an essential role in mediating the binding of sperm to the zona pellucida.

Hypogravity's Effect on the Life Cycle of Japanese Quail

NASA Technical Reports Server (NTRS)

Hester, Patricia Y.

1999-01-01

A series of studies were conducted to determine the effect of activities preceding space-flight and during space-flight on quail embryonic development. While the overall development of the quail embryos was evaluated, the report presented herein, focused on calcium utilization or uptake from eggshells by developing embryos during incubation in space and on earth. In the pre-space trials, fertilized quail eggs were subjected to pre-night dynamics including forces of centrifugation, vibration, or a combination of vibration and centrifugation prior to incubation for 6 or 16 days. In another trial, fertile quail eggs were tested for survivability in a refrigerator stowage kit for eggs (RSKE) which was subsequently used to transport the eggs to space. Eggs in the RSKE were subjected to shuttle launch dynamics including G force and random vibration profiles. In the space- flight trials, 48 fertile quail eggs were launched on space shuttle Flight STS-76 and were subsequently incubated in a Slovakian incubator onboard space station, MIR. Two sets of ground controls each with 48 fertile eggs with and without exposure to launch dynamics were initiated 5 days post-launch. There was a laboratory control (incubated in Lyon RX2 incubator at 37.5 C) and a synchronous control (incubated in Lyon RX2 incubator at 39 - 400 C), which simulated the temperature of the space-flight incubator. Following space-flight trials, post-flight trials were conducted where quail eggs were incubated in Lyon RX2 or Slovakian incubators under various temperatures with or without launch dynamics. Eggshells from all study trials were retrieved and analyzed for calcium content to determine if its utilization by developing quail embryos was affected by activities preceding space-flight or during incubation in space under microgravity. Results from the pre-flight and post-flight showed that pre-flight activities and shuttle launch dynamics had no effect on calcium uptake from the eggshell by developing embryos. However, calcium uptake from the eggshell by developing embryos incubated in micro,aravity was impaired by 12.6% when compared to embryos incubated on earth under laboratory control environment. This impairment was unlikely due to factors other than microgravity. In general, calcium utilization by developing embryos increased with age of incubation with the most increase occurring at day 16 of incubation.

Estrogenic activity and reproductive effects of the UV-filter oxybenzone (2-hydroxy-4-methoxyphenyl-methanone) in fish.

PubMed

Coronado, Michael; De Haro, Hector; Deng, Xin; Rempel, Mary Ann; Lavado, Ramon; Schlenk, Daniel

2008-11-21

Previous studies in extracts of sediments surrounding municipal outfalls off the coast of California, USA and effluents of New York City, NY, USA indicated the UV-filtering agent, oxybenzone (CAS# 131-57-7; benzophenone-3) as a potential estrogen. The effects of oxybenzone on estrogenic activity and reproduction were evaluated using a 14-day juvenile rainbow trout assay for plasma vitellogenin and a subsequent 21-day Japanese medaka reproduction assay. Significant induction of vitellogenin was observed in the rainbow trout at the 1000 microg/L nominal concentration (749 microg/L median measured value) of oxybenzone which was approximately 75 times greater than the concentrations observed in previous wastewater effluent. Vitellogenin induction was also observed in the 1000 microg/L nominal concentration (620 microg/L median measured) of oxybenzone in male Japanese medaka (Oryzias latipes) after 21 days of exposure. The number of eggs produced per female per day exposed to the same concentration (620 microg/L) were significantly lower after 7 days, but returned to control values after 21 days. Fertilized eggs were then monitored for 20 days to assess hatching success. The overall percentage of fertilized eggs collected during the 21-day exposure that hatched was significantly lower in the 620 microg/L oxybenzone concentration. There was also a temporal effect at this concentration as egg viability (percentage of fertilized eggs that hatched) was diminished 13-15 days after eggs were collected. All three oxybenzone concentrations (16, 132, and 620 microg/L) and the 50 ng/L estradiol positive control showed reduced hatching of eggs at day 15, and the 132 and 620 microg/L oxybenzone concentrations diminished the percentage of eggs that hatched on days 13-15. These data indicate that the UV-filter oxybenzone alters endocrine or reproduction endpoints in two fish species, but at concentrations significantly higher than those measured in the environment.

Some correlations between development and respiration in the sand dollar egg, as shown by cyanide inhibition studies.

PubMed

ROBBIE, W A

1948-01-30

Cyanide is a valuable tool for studying respiratory mechanisms and their rôle in embryonic development: it is relatively specific in its action, penetrates cell membranes readily, is active in low concentration, and may be controlled quantitatively (page 217). Echinarachnius is extremely sensitive to cyanide and the oxygen consumption of both eggs and of sperm is almost completely inhibited by 10(-5)M HCN (pages 219 and 221). Cell division is likewise arrested by the same concentration (page 223). One of the pronounced effects of an irreversible dosage of cyanide is the marked cytolysis or breakdown of the egg, both internally and at the cell membrane. This cytolysis appears to be related to the state of metabolism, and its occurrence varies with both the respiratory and developmental activity of the cell (page 224). The lethal dosage of cyanide varies with the state of development of the egg: the unfertilized egg is less susceptible than the fertilized one, and the susceptibility increases as the development of the fertilized egg proceeds (page 228). The Echinarachnius egg differs from that of Arbacia in respiratory behavior chiefly in its inability to survive prolonged anoxia: the sea urchin egg will tolerate for 24 hours a concentration of cyanide that kills the sand dollar eggs in 30 minutes (page 229). The Echinarachnius egg is apparently completely dependent upon cyanide-sensitive catalytic systems for its normal functioning and maintenance. Interference with this aerobic energy release mechanism results in irreversible damage to the egg (page 231).

SOME CORRELATIONS BETWEEN DEVELOPMENT AND RESPIRATION IN THE SAND DOLLAR EGG, AS SHOWN BY CYANIDE INHIBITION STUDIES

PubMed Central

Robbie, W. A.

1948-01-01

Cyanide is a valuable tool for studying respiratory mechanisms and their rôle in embryonic development: it is relatively specific in its action, penetrates cell membranes readily, is active in low concentration, and may be controlled quantitatively (page 217). Echinarachnius is extremely sensitive to cyanide and the oxygen consumption of both eggs and of sperm is almost completely inhibited by 10–5 M HCN (pages 219 and 221). Cell division is likewise arrested by the same concentration (page 223). One of the pronounced effects of an irreversible dosage of cyanide is the marked cytolysis or breakdown of the egg, both internally and at the cell membrane. This cytolysis appears to be related to the state of metabolism, and its occurrence varies with both the respiratory and developmental activity of the cell (page 224). The lethal dosage of cyanide varies with the state of development of the egg: the unfertilized egg is less susceptible than the fertilized one, and the susceptibility increases as the development of the fertilized egg proceeds (page 228). The Echinarachnius egg differs from that of Arbacia in respiratory behavior chiefly in its inability to survive prolonged anoxia: the sea urchin egg will tolerate for 24 hours a concentration of cyanide that kills the sand dollar eggs in 30 minutes (page 229). The Echinarachnius egg is apparently completely dependent upon cyanide-sensitive catalytic systems for its normal functioning and maintenance. Interference with this aerobic energy release mechanism results in irreversible damage to the egg (page 231). PMID:18920609

Transmission of lymphocystis disease virus to cultured gilthead seabream, Sparus aurata L., larvae.

PubMed

Cano, I; Valverde, E J; Garcia-Rosado, E; Alonso, M C; Lopez-Jimena, B; Ortiz-Delgado, J B; Borrego, J J; Sarasquete, C; Castro, D

2013-06-01

The transmission of lymphocystis disease virus (LCDV) to gilthead seabream, Sparus aurata L., larvae was investigated using fertilized eggs from a farm with previous reports of lymphocystis disease. LCDV genome was detected by PCR-hybridization in blood samples from 17.5% of the asymptomatic gilthead seabream broodstock analysed. Using the same methodology, eggs spawned from these animals were LCDV positive, as well as larvae hatched from them. The presence of infective viral particles was confirmed by cytopathic effects development on SAF-1 cells. Whole-mount in situ hybridization (ISH) and immunohistochemistry (IHC) showed the presence of LCDV in the epidermis of larvae hatched from LCDV-positive eggs. When fertilized eggs were disinfected with iodine, no viral DNA was detected either in eggs (analysed by PCR-hybridization) or in larvae (PCR-hybridization and ISH). These results suggest the vertical transmission of LCDV, the virus being transmitted on the egg surface. Larvae hatched from disinfected eggs remain LCDV negative during the endotrophic phase, as showed by PCR-hybridization, ISH and IHC. After feeding on LCDV-positive rotifers, viral antigens were observed in the digestive tract, which suggests that viral entry could be achieved via the alimentary canal, and that rotifers can act as a vector in LCDV transmission to gilthead seabream larvae. © 2012 Blackwell Publishing Ltd.

The dynamics of plasma membrane PtdIns(4,5)P(2) at fertilization of mouse eggs.

PubMed

Halet, Guillaume; Tunwell, Richard; Balla, Tamas; Swann, Karl; Carroll, John

2002-05-15

A series of intracellular Ca2+ oscillations are responsible for triggering egg activation and cortical granule exocytosis at fertilization in mammals. These Ca2+ oscillations are generated by an increase in inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)], which results from the hydrolysis of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P(2)]. Using confocal imaging to simultaneously monitor Ca2+ and plasma membrane PtdIns(4,5)P(2) in single living mouse eggs we have sought to establish the relationship between the kinetics of PtdIns(4,5)P(2) metabolism and the Ca2+ oscillations at fertilization. We report that there is no detectable net loss of plasma membrane PtdIns(4,5)P(2) either during the latent period or during the subsequent Ca2+ oscillations. When phosphatidylinositol 4-kinase is inhibited with micromolar wortmannin a limited decrease in plasma membrane PtdIns(4,5)P(2) is detected in half the eggs studied. Although we were unable to detect a widespread loss of PtdIns(4,5)P(2), we found that fertilization triggers a net increase in plasma membrane PtdIns(4,5)P(2) that is localized to the vegetal cortex. The fertilization-induced increase in PtdIns(4,5)P(2) follows the increase in Ca2+, is blocked by Ca2+ buffers and can be mimicked, albeit with slower kinetics, by photoreleasing Ins(1,4,5)P(3). Inhibition of Ca2+-dependent exocytosis of cortical granules, without interfering with Ca2+ transients, inhibits the PtdIns(4,5)P(2) increase. The increase appears to be due to de novo synthesis since it is inhibited by micromolar wortmannin. Finally, there is no increase in PtdIns(4,5)P(2) in immature oocytes that are not competent to extrude cortical granules. These studies suggest that fertilization does not deplete plasma membrane PtdIns(4,5)P(2) and that one of the pathways for increasing PtdIns(4,5)P(2) at fertilization is invoked by exocytosis of cortical granules.

Nematode development after removal of egg cytoplasm: absence of localized unbound determinants.

PubMed

Laufer, J S; von Ehrenstein, G

1981-01-23

Embryos of Caenorhabditis elegans develop into fertile adults after cell fragments, containing presumptive cytoplasm of somatic and germ line precursors, are extruded from uncleaved eggs or early blastomeres through laser-induced holes in the eggshells. This suggests that the determinate development of this worm is not dependent on the prelocalization of determinants in specific regions of the egg cytoplasm.

Does magnesium hardness in hatching waters affect the fertilization and hatching success of hybrid catfish eggs

USDA-ARS?s Scientific Manuscript database

Embryonic development is deemed to be the most sensitive stage in the life cycle of a teleost. As egg development takes outside the fish’s body, water hardness is one abioitic parameter, suggested to have a major effect on egg development and embryo survival. Ca2+ and Mg2+ contribute to water har...

Biology of Fopius arisanus (Hymenoptera: Braconidae) in Two Species of Fruit Flies

PubMed Central

Groth, M. Z.; Loeck, A. E.; Nörnberg, S. D.; Bernardi, D.; Nava, D. E.

2016-01-01

Fopius arisanus (Sonan, 1932) (Hymenoptera: Braconidae) is an egg–larval parasitoid used in control programs of Bactrocera dorsalis (Hendel) and Ceratitis capitata (Wiedemann). In Brazil, C. capitata and Anastrepha fraterculus (Wiedemann) are considered the main tephritid pests of exotic and indigenous fruits. The objective of this study was to study the biology of F. arisanus in C. capitata and A. fraterculus. Eggs of the two fruit fly species were used to determine the parasitism rate, number of offspring, emergence rate, sex ratio, adult weight and longevity of male and female F. arisanus. These biological parameters were used to develop a fertility life table. We observed higher parasitism and emergence rates of adults, a shorter duration of the egg–adult period and a sex ratio biased to females when F. arisanus was reared in eggs of C. capitata than in those of A. fraterculus. However, adults of F. arisanus from eggs of A. fraterculus were heavier and had greater longevity than those obtained from C. capitata eggs. The fertility life table showed better biological and reproductive performance for F. arisanus reared in eggs of C. capitata, although eggs of A. fraterculus also provided positive values for population increase. PMID:27638954

Relationship between maternal immunological response during pregnancy and onset of preeclampsia.

PubMed

Martínez-Varea, Alicia; Pellicer, Begoña; Perales-Marín, Alfredo; Pellicer, Antonio

2014-01-01

Maternofetal immune tolerance is essential to maintain pregnancy. The maternal immunological tolerance to the semiallogeneic fetus becomes greater in egg donation pregnancies with unrelated donors as the complete fetal genome is allogeneic to the mother. Instead of being rejected, the allogeneic fetus is tolerated by the pregnant woman in egg donation pregnancies. It has been reported that maternal morbidity during egg donation pregnancies is higher as compared with spontaneous or in vitro fertilization pregnancies. Particularly, egg donation pregnancies are associated with a higher incidence of pregnancy-induced hypertension and placental pathology. Preeclampsia, a pregnancy-specific disease characterized by the development of both hypertension and proteinuria, remains the leading cause of maternal and perinatal mortality and morbidity. The aim of this review is to characterize and relate the maternofetal immunological tolerance phenomenon during pregnancies with a semiallogenic fetus, which are the spontaneously conceived pregnancies and in vitro fertilization pregnancies, and those with an allogeneic fetus or egg donation pregnancies. Maternofetal immune tolerance in uncomplicated pregnancies and pathological pregnancies, such as those with preeclampsia, has also been assessed. Moreover, whether an inadequate maternal immunological response to the allogenic fetus could lead to a higher prevalence of preeclampsia in egg donation pregnancies has been addressed.

Anti-snake venom activities of ethanolic extract of fruits of Piper longum L. (Piperaceae) against Russell's viper venom: characterization of piperine as active principle.

PubMed

Shenoy, P A; Nipate, S S; Sonpetkar, J M; Salvi, N C; Waghmare, A B; Chaudhari, P D

2013-05-20

Piper longum L. fruits have been traditionally used against snakebites in north-eastern and southern region of India. To examine the ability of ethanolic extract of fruits of Piper longum L., Piperaceae (PLE) and piperine, one of the main active principles of Piper longum, to inhibit the Russell's viper (Doboia russelii, Viperidae) snake venom activities. Anti-snake venom activities of ethanolic extract of fruits of Piper longum L. (Piperaceae) and piperine against Russell's viper venom was studied in embryonated fertile chicken eggs, mice and rats by using various models as follows: inhibition of venom lethal action, inhibition of venom haemorrhagic action (in vitro), inhibition of venom haemorrhagic action (in vivo), inhibition of venom necrotizing action, inhibition of venom defibrinogenating action, inhibition of venom induced paw edema, inhibition of venom induced mast cell degranulation, creatine kinase assay and assay for catalase activity. PLE was found to inhibit the venom induced haemorrhage in embryonated fertile chicken eggs. Administration of PLE and piperine significantly (p<0.01) inhibited venom induced lethality, haemorrhage, necrosis, defibrinogenation and inflammatory paw edema in mice in a dose dependent manner. PLE and piperine also significantly (p<0.01) reduced venom induced mast cell degranulation in rats. Venom induced decrease in catalase enzyme levels in mice kidney tissue and increase in creatine kinase enzyme levels in mice serum were significantly (p<0.01) reversed by administration of both PLE and piperine. PLE possesses good anti-snake venom properties and piperine is one of the compounds responsible for the effective venom neutralizing ability of the plant. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Mature Oocyte Cryopreservation for Fertility Preservation.

PubMed

Liang, Tina; Motan, Tarek

2016-01-01

In recent decades, advances in cancer treatment have led to a dramatic improvement in long term survival. This has led to an increasing focus on quality of life after surviving cancer treatment, with fertility being an important aspect. Given the known reproductive risks of cancer therapies, there has been a growing interest in the field of fertility preservation (also referred to as oncofertility). Mature oocyte cryopreservation is no longer considered experimental and has become a realistic option for reproductive aged women prior to undergoing cancer treatment. Additionally, as cryopreservation techniques improve, mature oocyte cryopreservation is increasing being marketed to healthy women without cancer wishing to delay child bearing, also termed "social egg freezing". This chapter provides a review of the current technology, use, and outcomes of mature oocyte cryopreservation. It also outlines the ethical debate surrounding social egg freezing and directions for future research in female fertility preservation.

Captive propagation of bald eagles at Patuxent Wildlife Research Center and introductions into the wild, 1976-80

USGS Publications Warehouse

Wiemeyer, Stanley N.

1981-01-01

One to 5 pairs of the Bald Eagle (Haliaeetus leucocephalus) were in the captive propagation project at Patuxent Wildlife Research Center during 1976-80. Four pairs produced viable eggs or young by natural mating in one or more years. Pairs laid second clutches 9 of 11 times when their first clutches were collected within 8 days of clutch completion. Sixty-nine percent of fertile artificially incubated eggs hatched; 93% of fertile parent-incubated eggs hatched. Eleven eaglets from artificially incubated eggs were hand reared. Age of birds at the time they were acquired from the wild was not a factor in their reproductive success. Ten hand-reared and 2 parent-reared young were fostered to adult Bald Eagles at active wild nests; 11 were accepted and survived. Eleven parent-reared young were provided to hacking projects. Egg transplants to wild nests were conducted, but discontinued because of poor success. Double clutching of captive pairs has not resulted in substantially increased numbers of eaglets. Additional research is needed in artificial incubation, artificial insemination, and nutrition and care of hand-reared eaglets.

Reproductive success of rose-ringed parakeets Psittacula krameri in a captive UK population.

PubMed

Lambert, Mark S; Massei, Giovanna; Bell, Jennifer; Berry, Leslie; Haigh, Carol; Cowan, David P

2009-11-01

Rose-ringed parakeets Psittacula krameri (Scop.) have recently become established in several European countries, with potential for significant negative economic and ecological impacts. However, in northern Europe the potential for reproductive output is largely unknown. In 2005 the authors established a captive outdoor colony in north-east England and examined breeding success over 2 years. In 2006 (19 pairs, 15 clutches) the average first clutch size was 3.6 (+/-0.3) eggs. Six clutches were infertile, and overall the colony produced 1.4 (+/-0.5) fertile eggs per pair. Eleven pairs produced a second clutch following removal of the first; seven were infertile, and overall productivity was 0.7 (+/-0.4) fertile eggs per pair. Unsuccessful pairs were rearranged or replaced. In 2007, overall productivity was 2.5 (+/-0.4) and 1.8 (+/-0.4) fertile eggs per pair for the first and second attempts respectively. For pairs that remained unchanged through 2006-2007, productivity was consistent between years and breeding attempts. Where food and nest sites were not limiting, clutch sizes in north-east England were similar to those in the native range, and consistent between first and second attempts. This has implications for the future expansion and management of the species. (c) Crown Copyright 2009. Reproduced with permission of Her Majesty's Stationery Office.

Birth of mice after in vitro fertilization using C57BL/6 sperm transported within epididymides at refrigerated temperatures.

PubMed

Mochida, K; Ohkawa, M; Inoue, K; Valdez, D M; Kasai, M; Ogura, A

2005-07-01

The transportation of cryopreserved spermatozoa is an economical, efficient, and safe method for the distribution of mouse strains from one facility to another. However, spermatozoa from some strains, including C57BL/6 (B6), are very sensitive to freezing and thawing and frequently fail to fertilize eggs by conventional in vitro fertilization methods at the recipient mouse facility. Since many genetically engineered mice have the B6 genetic background, this sensitivity poses a major obstacle to studies of mouse genetics. We investigated the feasibility of transporting spermatozoa within epididymides under non-freezing conditions. First, we examined the interval that B6 and B6D2F1 (BDF1) spermatozoa retained their ability to fertilize when stored within epididymides at low temperatures (5 degrees C or 7 degrees C). Fertilization rates were >50%, irrespective of the spermatozoa used, when epididymides were stored for 3d at 7 degrees C. B6 spermatozoa, but not BDF1 sperm, had better retention of fertilizing ability at 7 degrees C versus 5 degrees C. We then transported freshly collected B6 and BDF1 epididymides from a sender colony to a recipient colony using a common package delivery service, during which the temperature was maintained at 5 degrees C or 7 degrees C for 2d. Sufficiently high fertilization rates (68.0-77.5%) were obtained for all experimental groups, except for B6 spermatozoa transported at 5 degrees C. These spermatozoa were successfully cryopreserved at the recipient facility and, yielded post-thaw fertilization rates of 27.6-66.4%. When embryos derived from the B6 spermatozoa that were transported at 7 degrees C were transferred into recipient females, 52.7% (38/72) developed to term. In conclusion, transportation of epididymides at refrigerated temperatures is a practical method for the exchange of mouse genetic resources between facilities, especially when these facilities do not specialize in sperm cryopreservation. For the B6 mouse strain, the transportation of epididymides at 7 degrees C rather than 5 degrees C, is recommended.

Spacelab

NASA Image and Video Library

1994-07-01

Astronaut Donald Thomas conducts the Fertilization and Embryonic Development of Japanese Newt in Space (AstroNewt) experiment at the Aquatic Animal Experiment Unit (AAEU) inside the International Microgravity Laboratory-2 (IML-2) science module. The AstroNewt experiment aims to know the effects of gravity on the early developmental process of fertilized eggs using a unique aquatic animal, the Japanese red-bellied newt. The newt egg is a large single cell at the begirning of development. The Japanese newt mates in spring and autumn. In late autumn, female newts enter hibernation with sperm in their body cavity and in spring lay eggs and fertilize them with the stored sperm. The experiment takes advantage of this feature of the newt. Groups of newts were sent to the Kennedy Space Center and kept in hibernation until the mission. The AAEU cassettes carried four newts aboard the Space Shuttle. Two newts in one cassette are treated by hormone injection on the ground to simulate egg laying. The other two newts are treated on orbit by the crew. The former group started maturization of eggs before launch. The effects of gravity on that early process were differentiated by comparison of the two groups. The IML-2 was the second in a series of Spacelab flights designed to conduct research by the international science community in a microgravity environment. Managed by the Marshall Space Flight Center, the IML-2 was launched on July 8, 1994 aboard the STS-65 Space Shuttle mission, Orbiter Columbia.

Spacelab

NASA Image and Video Library

1994-07-01

Astronaut Donald Thomas conducts the Fertilization and Embryonic Development of Japanese Newt in Space (AstroNewt) experiment at the Aquatic Animal Experiment Unit (AAEU) inside the International Microgravity Laboratory-2 (IML-2) science module. The AstroNewt experiment aims to know the effects of gravity on the early developmental process of fertilized eggs using a unique aquatic animal, the Japanese red-bellied newt. The newt egg is a large single cell at the begirning of development. The Japanese newt mates in spring and autumn. In late autumn, female newts enter hibernation with sperm in their body cavity and in spring lay eggs and fertilized them with the stored sperm. The experiment takes advantage of this feature of the newt. Groups of newts were sent to the Kennedy Space Center and kept in hibernation until the mission. The AAEU cassettes carried four newts aboard the Space Shuttle. Two newts in one cassette are treated by hormone injection on the ground to simulate egg laying. The other two newts are treated on orbit by the crew. The former group started maturization of eggs before launch. The effects of gravity on that early process were differentiated by comparison of the two groups. The IML-2 was the second in a series of Spacelab flights designed to conduct research by the international science community in a microgravity environment. Managed by the Marshall Space Flight Center, the IML-2 was launch on July 8, 1994 aboard the STS-65 Space Shuttle Orbiter Columbia mission.

Twins, Triplets, and Other Multiples

MedlinePlus

... one baby naturally. Another reason is that more women are using fertility treatments to help them conceive. How twins are formed Twins form in one of two ways: Identical twins occur when a single fertilized egg splits into two. Identical twins look ...

Isolation and Characterization of Sex-Linked Female-Sterile Mutants in DROSOPHILA MELANOGASTER

PubMed Central

Gans, Madeleine; Audit, Claudie; Masson, Michele

1975-01-01

The purpose of the experiments described was to identify X chromosome genes functioning mainly or exclusively during oogenesis. Two mutagenesis experiments were carried out with ethyl methane sulfonate. Following treatment inducing 60% lethals, 9% of the treated X chromosomes carried a female sterility mutation which did not otherwise seriously affect viability. Among —95 isolated mutants, 19 were heat-sensitive and 5 cold-sensitive. The mutants have been classified as follows: I (16 mutants; 12 complementation groups): the females laid few or no eggs; the defect concerned either ovulation or oogenesis. II (37 mutants; 18 complementation groups): the female laid morphologically abnormal eggs, often with increased membrane permeability. III A (13 mutants; at least 8 complementation groups): the homozygous females were sterile if mated to mutant males; their progeny (homo- and hemizygous) died at a late embryonic stage (11 mutants), at the larval stage (1 mutant) or at the pupal stage (1 mutant). However fertility was partly restored by breeding to wild-type males as shown by survival of some heterozygous descendants. III B (29 mutants; 22 complementation groups): the fertility of the females was not restored by breeding to a wild-type male. Most of the eggs of 13 of the mutants died at a late stage of embryogenesis. The eggs of the others ceased development earlier or, perhaps, remained unfertilized. The distribution of the number of mutants per complementation group led to an estimation of a total of about 150 X-linked genes involved in female fertility. The females of three mutants, heat-sensitive and totally sterile at 29°, produced at a lower temperature descendants morphologically abnormal or deprived of germ cells. Three other mutants not described in detail showed a reduction in female fertility with many descendants lacking germ cells. A desirable mutant which was not recovered was one with normal fertile females producing descendants which, regardless of their genotype, bore specific morphological abnormalities. The value of the mutants isolated for analysis of the complex processes leading to egg formation and initiation of development is discussed. PMID:814037

Efficient utilization of very dilute aquatic sperm: sperm competition may be more likely than sperm limitation when eggs are retained.

PubMed

Pemberton, Andrew J; Hughes, Roger N; Manríquez, Patricio H; Bishop, John D D

2003-11-07

Fertilization success may be severely limited in marine invertebrates that spawn both male and female gametes. In a diverse group of aquatic organisms only sperm are released, with sperm-egg fusion occurring at the mother. Here, we report fertilization kinetics data for two such 'brooding' or 'spermcast' species--representing each major clade of the animal kingdom. High levels of fertilization were achieved at sperm concentrations of two or three orders of magnitude lower than is common with broadcast spawning species. At a concentration of 100 sperm ml(-1), fertilization rates of a bryozoan and colonial ascidian were near maximum, whereas most broadcast spawners would have displayed near complete reproductive failure. A further experiment looked at the rate of uptake of sperm under natural conditions. Results suggested that sperm released at ca. 0.9 m from an acting female could be collected at a rate of 3-12 times greater than the minimum required simply to avoid sperm limitation. Thus, evolutionary pressures on gametic and other reproductive characteristics of many species that release sperm but retain eggs may be quite different from those of broadcast spawners and may confer on the former an enhanced scope for sperm competition and female choice.

Influence of fertilizing water pH on the hatching success of stripped channel catfish eggs on channel x blue hybrid catfish embryo production in hatcheries

USDA-ARS?s Scientific Manuscript database

Variable egg quality is one of the most important constrains to the development of aquaculture. The quality of eggs that are manually stripped from channel catfish are affected by variation in parental genetics, maturity, type and dose of hormone, age and pre-spawning stress of female fish. Furthe...

Marchantia MpRKD Regulates the Gametophyte-Sporophyte Transition by Keeping Egg Cells Quiescent in the Absence of Fertilization.

PubMed

Rövekamp, Moritz; Bowman, John L; Grossniklaus, Ueli

2016-07-11

Unlike in animals, the life cycle of land plants alternates between two multicellular generations, the haploid gametophyte and the diploid sporophyte [1]. Gamete differentiation initiates the transition from the gametophyte to the sporophyte generation and, upon maturation, the egg cell establishes a quiescent state that is maintained until fertilization. This quiescence represents a hallmark of the gametophyte-sporophyte transition. The underlying molecular mechanisms are complex and best characterized in the flowering plant Arabidopsis thaliana [2-4]. However, only few genes with egg cell-specific expression or defects have been identified [5-10]. Intriguingly, ectopic expression of members of a clade of RWP-RK domain (RKD)-containing transcription factors, which are absent from animal genomes [11-13], can induce an egg cell-like transcriptome in sporophytic cells of A. thaliana. Yet, to date, loss-of-function experiments have not produced phenotypes affecting the egg cell, likely due to genetic redundancy and/or cross-regulation among the five RKD genes of A. thaliana [10]. To reduce genetic complexity, we explored the genome of Marchantia polymorpha, a liverwort belonging to the basal lineage of extant land plants [14-17]. Based on sequence homology, we identified a single M. polymorpha RKD gene, MpRKD, which is orthologous to all five A. thaliana RKD genes. Analysis of the MpRKD expression pattern and characterization of lines with reduced MpRKD activity indicate that it functions as a regulator of gametophyte development and the gametophyte-sporophyte transition. In particular, MpRKD is required to establish and/or maintain the quiescent state of the egg cell in the absence of fertilization. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impact of cage stocking density on egg laying characteristics and related stress and immunity parameters of Japanese quails in subtropics.

PubMed

El-Tarabany, M S

2016-10-01

The aim of this study was to investigate the effects of different cage stocking densities on egg production parameters, as well as related stress and immunity indices in Japanese quails under subtropical Egyptian conditions. Two hundred and sixteen birds of Japanese quail at 14th week of age were used in this experiment. The birds were divided randomly into three groups: 60, 72 and 84. Each group subdivided into 4 replicates, where the cages' floor spaces were 200 (S1 ), 167 (S2 ) and 143 (S3 ) cm(2) /bird, respectively. Birds housed at 200 cm(2) /bird (S1 ) had superior fertility (fertility % (p = 0.013) and hatchability % (p = 0.041)), egg production (egg weight (p = 0.034) and egg mass (p = 0.001)) and immunity parameters (higher geometric mean of antibody titres against Newcastle disease virus, p = 0.024). Furthermore, they had higher internal egg quality score: albumen height (p = 0.003), yolk height (p = 0.023), yolk index (p = 0.006) and Haugh unit (p = 0.035). Birds housed at 143 cm(2) /bird (S3 ) had the lowest total leucocytic count and lymphocyte % (p = 0.022), but the highest H/L ratio (p = 0.001). Corticosterone concentration was lower in S1 group (p = 0.031) than that in groups housed at higher densities. Japanese quail housed at high densities revealed drop in fertility, hatchability, production and immunity parameters, indicating a detrimental effects on both welfare and economic income. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Two Dimensional Finite Element Model to Study Calcium Distribution in Oocytes

NASA Astrophysics Data System (ADS)

Naik, Parvaiz Ahmad; Pardasani, Kamal Raj

2015-06-01

Cytosolic free calcium concentration is a key regulatory factor and perhaps the most widely used means of controlling cellular function. Calcium can enter cells through different pathways which are activated by specific stimuli including membrane depolarization, chemical signals and calcium depletion of intracellular stores. One of the important components of oocyte maturation is differentiation of the Ca2+ signaling machinery which is essential for egg activation after fertilization. Eggs acquire the ability to produce the fertilization-specific calcium signal during oocyte maturation. The calcium concentration patterns required during different stages of oocyte maturation are still not completely known. Also the mechanisms involved in calcium dynamics in oocyte cell are still not well understood. In view of above a two dimensional FEM model has been proposed to study calcium distribution in an oocyte cell. The parameters such as buffers, ryanodine receptor, SERCA pump and voltage gated calcium channel are incorporated in the model. Based on the biophysical conditions the initial and boundary conditions have been framed. The model is transformed into variational form and Ritz finite element method has been employed to obtain the solution. A program has been developed in MATLAB 7.10 for the entire problem and executed to obtain numerical results. The numerical results have been used to study the effect of buffers, RyR, SERCA pump and VGCC on calcium distribution in an oocyte cell.

[Female age - related fertility decline: Far from the myth of the "selfish working-girl" and the "right to have a child"].

PubMed

Vialle, M; Perrin, J; Amar-Hoffet, A; Boyer, P; Courbiere, B

2016-04-01

To study the social dimension of age-related female infertility through an analysis of three key themes: the personal life histories of infertile women over 40 years of age; representations of age and the desire to become pregnant after age 40; opinions of French legislations framing Assisted Reproductive Technologies, age limits, egg donation, and egg freezing for non-medical reasons. This qualitative sociological study was based on semi-structured interviews with infertile women over age 40 going through fertility treatments. The interviews contained three parts: personal and relationship histories; experiences related to age; opinions related to French legislation. Twenty-three interviews were conducted; each lasting between 90 to 120minutes. Far from having similar life histories, the women interviewed had very different backgrounds leading to their desire for a pregnancy after 40 years of age. From the beginning of their fertility treatments, they perceived a "race against the clock". This feeling of urgency accompanied their experiences and was related to the desire to not be too old for their future child. The women interviewed were mainly in favor of loosening French bioethical laws in order to avoid the need to travel abroad to pursue fertility treatments. The profiles studied attest to a growing gap between biological and biographical temporalities, as well as an inability of women to reduce their desire for a child. Faced with this disparity, egg donation and egg freezing were seen as practical solutions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The Acp26Aa seminal fluid protein is a modulator of early egg hatchability in Drosophila melanogaster.

PubMed

Chapman, T; Herndon, L A; Heifetz, Y; Partridge, L; Wolfner, M F

2001-08-22

Drosophila melanogaster male accessory gland proteins (Acps) that are transferred in the ejaculate with sperm mediate post-mating competition for fertilizations between males. The actions of Acps include effects on oviposition and ovulation, receptivity and sperm storage. Two Acps that modulate egg production are Acp26Aa (ovulin) and Acp70A (the sex peptide). Acp26Aa acts specifically on the process of ovulation (the release of mature eggs from the ovaries), which is initiated 1.5 h after mating. In contrast, sperm storage can take as long as 6-9 h to complete. Initial ovulations after matings by virgin females will therefore occur before all sperm are fully stored and the extra eggs initially laid as a result of Acp26Aa transfer are expected to be inefficiently fertilized. Acp26Aa-mediated release of existing eggs should not cause a significant energetic cost or lead to a decrease in female lifespan assuming, as seems likely, that the energetic cost of egg laying comes from de novo egg synthesis (oogenesis) rather than from ovulation. We tested these predictions using Acp26Aa(1) mutant males that lack Acp26Aa but are normal for other Acps and Acp26Aa(2) males that transfer a truncated but fully functional Acp26Aa protein. Females mating with Acp26Aa(2) (truncation) males that received functional Acp26Aa produced significantly more eggs following their first matings than did mates of Acp26Aa(1) (null) males. However, as predicted above, these extra eggs, which were laid as a result of Acp26Aa transfer to virgin females, showed significantly lower egg hatchability. Control experiments indicated that this lower hatchability was due to lower rates of fertilization at early post-mating times. There was no drop in egg hatchability in subsequent non-virgin matings. In addition, as predicted above, females that did or did not receive Acp26Aa did not differ in survival, lifetime fecundity or lifetime progeny, indicating that Acp26Aa transfer does not represent a significant energetic cost for females and does not contribute to the survival cost of mating. Acp26Aa appears to remove a block to oogenesis by causing the clearing out of existing mature eggs and, thus, indirectly allowing oogenesis to be initiated immediately after mating. The results show that subtle processes coordinate the stimulation of egg production and sperm storage in mating pairs.

Fertilization: a sperm’s journey to and interaction with the oocyte

PubMed Central

Ikawa, Masahito; Inoue, Naokazu; Benham, Adam M.; Okabe, Masaru

2010-01-01

Mammalian fertilization comprises sperm migration through the female reproductive tract, biochemical and morphological changes to sperm, and sperm-egg interaction in the oviduct. Recent gene knockout approaches in mice have revealed that many factors previously considered important for fertilization are largely dispensable, or if they are essential, they have an unexpected function. These results indicate that what has been observed in in vitro fertilization (IVF) differs significantly from what occurs during “physiological” fertilization. This Review focuses on the advantages of studying fertilization using gene-manipulated animals and highlights an emerging molecular mechanism of mammalian fertilization. PMID:20364096

Amphibian egg cytoplasm response to altered g-forces and gravity orientation

NASA Technical Reports Server (NTRS)

Neff, A. W.; Smith, R. C.; Malacinski, G. M.

1986-01-01

Elucidation of dorsal/ventral polarity and primary embryonic axis development in amphibian embryos requires an understanding of cytoplasmic rearrangements in fertile eggs at the biophysical, physiological, and biochemical levels. Evidence is presented that amphibian egg cytoplasmic components are compartmentalized. The effects of altered orientation to the gravitational vector (i.e., egg inversion) and alterations in gravity force ranging from hypergravity (centrifugation) to simulated microgravity (i.e., horizontal clinostat rotation) on cytoplasmic compartment rearrangements are reviewed. The behavior of yolk compartments as well as a newly defined (with monoclonal antibody) nonyolk cytoplasmic compartment, in inverted eggs and in eggs rotated on horizontal clinostats at their buoyant density, is discussed.

Quantitative mapping of zinc fluxes in the mammalian egg reveals the origin of fertilization-induced zinc sparks

DOE PAGES

Que, Emily L.; Bleher, Reiner; Duncan, Francesca E.; ...

2014-12-15

Fertilization of a mammalian egg induces a series of ‘zinc sparks’ that are necessary for inducing the egg-to-embryo transition. Despite the importance of these zinc efflux events little is known about their origin. To understand the molecular mechanism of the zinc spark we combined four physical approaches to resolve zinc distributions in single cells: a chemical probe for dynamic live-cell fluorescence imaging and a combination of scanning transmission electron microscopy with energy dispersive spectroscopy, X-ray fluorescence microscopy, and 3D elemental tomography for high resolution elemental mapping. Here we show that the zinc spark arises from a system of thousands ofmore » zinc-loaded vesicles, each of which contains, on average, 106 zinc atoms. These vesicles undergo dynamic movement during oocyte maturation and exocytosis at the time of fertilization. We conclude that the discovery of these vesicles and the demonstration that zinc sparks originate from them provides a quantitative framework for understanding how zinc fluxes regulate cellular processes.« less

ERK1/2 mediates sperm acrosome reaction through elevation of intracellular calcium concentration.

PubMed

Jaldety, Yael; Breitbart, Haim

2015-10-01

Mammalian sperm acquire fertilization capacity after residing in the female reproductive tract for a few hours in a process called capacitation. Only capacitated sperm can bind the zona pellucida (ZP) of the egg and undergo the acrosome reaction, a process that allows penetration and fertilization. Extracellular signal regulated kinase (ERK1/2) mediates signalling in many cell types, however its role in sperm function is largely unknown. Here we show that ERK1/2 is highly phosphorylated/activated after a short incubation of mouse sperm under capacitation conditions and that this phosphorylation is reduced after longer incubation. Further phosphorylation was observed upon addition of crude extract of egg ZP or epidermal growth factor (EGF). The mitogen-activated ERK-kinase (MEK) inhibitor U0126 abolished ERK1/2 phosphorylation, in vitro fertilization rate and the acrosome reaction induced by ZP or EGF but not by the Ca2+-ionophore A23187. Moreover, inhibition of ERK1/2 along the capacitation process diminished almost completely the sperm's ability to go through the acrosome reaction, while inhibition at the end of capacitation attenuated the acrosome reaction rate by only 45%. The fact that the acrosome reaction, induced by the Ca2+ -ionophore A23187, was not inhibited by U0126 suggests that ERK1/2 mediates the acrosome reaction by activating Ca2+ transport into the cell. Direct determination of intracellular [Ca2+] revealed that Ca2+ influx induced by EGF or ZP was completely blocked by U0126. Thus, it has been established that the increase in ERK1/2 phosphorylation/activation in response to ZP or by activation of the EGF receptor (EGFR) by EGF, is a key event for intracellular Ca2+ elevation and the subsequent occurrence of the acrosome reaction.

EXPERIMENTAL STUDIES ON EMBRYOGENESIS IN HYDROZOANS (TRACHYLINA AND SIPHONOPHORA) WITH DIRECT DEVELOPMENT.

PubMed

Freeman, Gary

1983-12-01

The normal embryology of the trachymedusa Aglantha digitale and the siphonophores Nanomia cara and Muggiaea atlantica is described. Marking experiments on these embryos indicate that the site of first cleavage initiation corresponds to the oral pole of the oral-aboral axis. In Muggiaea the plane of the first cleavage corresponds to the plane of bilateral symmetry. Experiments in which presumptive aboral and oral regions are isolated from these embryos at different stages of development indicate that there is an early determination of different regions along this axis. Only the oral region of the Muggiaea embryo has the ability to regulate. These eggs have a pronounced centrolecithal organization. As a consequence of cleavage, the outer ectoplasmic layer of the egg ends up in the cells that form the ectoderm, while the inner or endoplasmic region of the egg ends up in the cells that form the endoderm. Experimentally created fragments of fertilized eggs that contain only ectoplasm differentiate to form an unorganized ectodermal cell mass, indicating that endoplasm is necessary in order to differentiate endoderm. The process of embryogenesis in these animals and the developmental mechanisms they use are very different from those used by hydrozoans with indirect development. These embryos use a suite of developmental mechanisms which are very similar to those used by ctenophores. The significance of this similarity is discussed.

The role of the actin cytoskeleton in calcium signaling in starfish oocytes.

PubMed

Santella, Luigia; Puppo, Agostina; Chun, Jong Tai

2008-01-01

Ca2+ is the most universal second messenger in cells from the very first moment of fertilization. In all animal species, fertilized eggs exhibit massive mobilization of intracellular Ca2+ to orchestrate the initial events of development. Echinoderm eggs have been an excellent model system for studying fertilization and the cell cycle due to their large size and abundance. In preparation for fertilization, the cell cycle-arrested oocytes must undergo meiotic maturation. Studies of starfish oocytes have shown that Ca2+ signaling is intimately involved in this process. Our knowledge of the molecular mechanism of meiotic maturation and fertilization has expanded greatly in the past two decades due to the discovery of cell cycle-related kinases and Ca2+-mobilizing second messengers. However, the molecular details of their actions await elucidation of other cellular elements that assist in the creation and transduction of Ca2+ signals. In this regard, the actin cytoskeleton, the receptors for second messengers and the Ca2+-binding proteins also require more attention. This article reviews the physiological significance and the mechanism of intracellular Ca2+ mobilization in starfish oocytes during maturation and fertilization.

Effects of Salivary Gland Hypertrophy Virus on the Reproductive Behavior of the Housefly, Musca domestica▿

PubMed Central

Lietze, Verena-Ulrike; Geden, Christopher J.; Blackburn, Patrick; Boucias, Drion G.

2007-01-01

Pathological studies demonstrated that the salivary gland hypertrophy virus of houseflies (MdSGHV) shuts down reproduction in infected females. The mechanism that underlay the disruption of reproduction functioned on several levels. Females infected at the previtellogenic stage did not produce eggs, reflecting a block in the gonadotropic cycle. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analysis of hemolymph samples demonstrated that MdSGHV infection reduced the levels of both the female-specific hexamerin and egg yolk proteins. Furthermore, reverse transcriptase quantitative real-time PCR data demonstrated that infection blocked hexamerin and yolk protein gene transcription. When females were allowed to develop eggs prior to infection (postvitellogenic stage), the outcome of mating attempts depended upon when mating took place. If egg-containing, virus-infected females were mated within 24 h of infection, they copulated and deposited a single batch of fertilized eggs. However, if mating was delayed for a longer period, the egg-containing females refused to copulate with healthy males. Both of these results suggested that a virus-induced signal influenced the central nervous system, shutting down female receptivity and egg production. All experiments demonstrated that MdSGHV-infected males did not display azoospermia and were fertile. Both healthy females mated with infected males, and the resulting F1 progeny were free of salivary gland hypertrophy symptoms, which suggests that the virus is not sexually or vertically transmitted. PMID:17827327

Determination of cortisol in lake sturgeon (Acipenser fulvescens) eggs by liquid chromatography tandem mass spectrometry.

PubMed

Bussy, Ugo; Wassink, Lydia; Scribner, Kim T; Li, Weiming

2017-01-01

Quantifying cortisol concentrations in fish eggs is important to understand the effects of environmental conditions on maternal physiological condition and on egg provisioning and quality. Data are particularly relevant to studies of the ecology of threatened species such as lake sturgeon (Aciperser fulvescens) as well as assessments of larval physical and behavioral phenotypes, fish health and caviar quality in sturgeon aquaculture. This study focuses on development of bioanalytical methods for high sensitivity and robust determination of cortisol in sturgeon eggs. Sample preparation was optimized after investigating protein precipitation and liquid-liquid extraction techniques. Ethyl acetate was found to be the most efficient solvent (recovery parameter) and also provided the best sample clean up (matrix effect parameter). The method was determined to be linear for cortisol concentrations between 0.025 and 100ng/mL. The limits of detection and quantification were 0.025 and 0.1ng/mL respectively. Intra- and inter-day performances of the method were validated at three concentrations (0.25; 10 and 100ng/mL). The method was applied to field-collected samples for the determination of endogenous cortisol in lake sturgeon eggs. Cortisol was detected in all egg samples and statistical analysis showed significant differences between fertilized and non-fertilized eggs. Copyright © 2016 Elsevier B.V. All rights reserved.

Dietary lufenuron reduces egg hatch and influences protein expression in the fruit fly Bactrocera latifrons (Hendel).

PubMed

Chang, Chiou Ling; Geib, Scott; Cho, Il Kyu; Li, Qing X; Stanley, David

2014-08-01

Lufenuron (LFN), a chitin synthase inhibitor, impacts the fertility of Ceratitis capitata, Bactrocera dorsalis, B. cucurbitae, and B. latifrons. We posed the hypothesis that LFN curtails egg hatch in the solanaceous fruit fly, B. latifrons. In this study, newly emerged virgin adults were sexed and fed for 12 days with varying concentrations of LFN-laced agar diets until sexual maturation. Eggs were collected from 12-d-old adults and the egg hatch was assessed. Egg hatch decreased in adults reared on LFN-treated diets. LFN-treated media did not influence fertility after one gender was reared on experimental and the other on control media before mating. Exposure to LFN-treated medium after mating led to reduced egg hatch. We infer that LFN is not a permanent sterilant, and reduced egg hatch depends on continuous exposure to dietary LFN after mating. Proteomic analysis identified two differentially expressed proteins, a pheromone binding protein and a chitin binding protein, between adults maintained on LFN-treated and control diets. Expression of two genes encoding chitin synthase 2, and chitin binding protein, was altered in adults exposed to dietary LFN. LFN treatments also led to increased expression of two odorant binding proteins one in females and one in males. We surmise these data support our hypothesis and provide insight into LFN actions. © 2014 Wiley Periodicals, Inc.

High Serum FSH is Associated with Brown Oocyte Formation and a Lower Pregnacy Rate in Human IVF Parctice.

PubMed

Xu, Hongyi; Deng, Kai; Luo, Qingbing; Chen, Juan; Zhang, Xin; Wang, Xiaoyan; Diao, Honglu; Zhang, Changjun

2016-01-01

To investigate whether brown zona pellucida (ZP) of oocytes affects the outcome of fertilization, embryo quality and pregnancy rate in in vitro fertilization-embryo transfer (IVF-ET). Based on the ZP color of their oocytes, a total number of 703 patients dated from 2012 to 2014 were divided into a normal egg group (group A) and a brown oocyte group (group B), with 629 and 74 cases, respectively. Clinical characteristics, gonadotropin (Gn) days, Gn dosage, serum hormone levels on the day of human chorionic gonadotropin (HCG) injection, ZP thickness (ZPT) of the eggs, fertilization rate, rescue intracytoplasmic sperm injection (rICSI) rate, good-quality embryo rate and pregnancy rate were compared between the two groups. No significant differences were found in the duration and the causes of infertility, and their basal level of endocrine hormone before IVF-ET between normal egg group and brown egg group. The level of serum hormone including estradiol, progesterone and luteinizing hormone on the day of HCG injection were again similar. Moreover, there were no differences in number of mature oocytes, oocyte fertilization rates and rICSI rates after IVF between the two groups. However, we observed that the ZPT of brown oocytes (group B) was higher than that of normal oocytes (group A). Moreover, the Gn dosage and FSH levels on the day of HCG injection were significantly higher in group B than in group A and the good-quality embryo rate and pregnancy rate in group B were lower than those in group A. Compared with normal eggs, oocytes with a brown ZP were found to have a higher ZPT, lower embryo quality and lower pregnancy rate, which might be due to a high Gn dosage injection and high serum FSH levels during IVT-ET cycles. © 2016 The Author(s) Published by S. Karger AG, Basel.

Sperm-egg penetration assay assessment of the contraceptive effects of glycerol and egg yolk in rooster sperm diluents.

PubMed

Abouelezz, F M K; Castaño, C; Toledano-Díaz, A; Esteso, M C; López-Sebastián, A; Campo, J L; Santiago-Moreno, J

2015-06-01

Glycerol (GLY) and egg yolk (EY) are good cryoprotectants of avian and mammalian sperm, but in birds, they strongly inhibit the eventual fertilization of ova. Using the sperm penetration (SP-holes) assay and fertility trials, the present study investigates (1) the possible mechanism by which this contraceptive effect occurs in chickens and (2) the maximum concentrations of GLY and EY tolerated by fresh rooster sperm. Seventy Black-Barred Andaluza hens (five per treatment) were inseminated four times (twice per week) with 0.1 mL of fresh semen from roosters of the same breed diluted 1:1 (v:v) with Lake and Ravie medium containing different concentrations of GLY or EY. No adverse effects on acrosome integrity, sperm motility, or viability were seen with any concentration of GLY or EY. The number of SP-holes on perivitelline layer samples taken from above the germinal disc became progressively lower at GLY concentrations of 1.5% or greater (P > 0.05). No holes caused by sperms were seen in unfertilized eggs. The corresponding fertility results showed similar reductions when the GLY concentration was 1.5% or greater. No changes in the number of SP-holes were seen with increasing EY concentrations (0%-7.5%), nor were any differences in fertility observed, except for a reduction when 15% EY was used. The results therefore reveal that GLY affects the transit of sperms through the oviduct in their attempt to reach the infundibulum area, limiting their access to the ovum perivitelline layer. Egg yolk had no such effect, nor did it influence acrosome reaction capacity; its mechanism of contraceptive action therefore remains unknown. The maximum GLY and EY concentrations tolerated by the rooster sperm were 0.75% and 7.5%, respectively. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of intracellular pH on the mitotic apparatus and mitotic stage in the sand dollar egg.

PubMed

Watanabe, K; Hamaguchi, M S; Hamaguchi, Y

1997-01-01

The effect of change in intracellular pH (pHi) on mitosis was investigated in the sand dollar egg. The pHi in the fertilized egg of Scaphechinus mirabilis and Clypeaster japonicus, which was 7.34 and 7.31, respectively, changed by means of treating the egg at nuclear envelope breakdown with sea water containing acetate and/or ammonia at various values of pH. The mitotic apparatus at pHi 6.70 became larger than that of normal fertilized eggs; that is, the mitotic spindle had the maximal size, especially in length at pHi 6.70. The spindle length linearly decreased when pHi increased from 6.70 to 7.84. By polarization microscopy, the increase in birefringence retardation was detected at slightly acidic pHi, suggesting that the increase in size of the spindle is caused by the increase in the amount of microtubules in the spindle. At pHi 6.30, the organization of the mitotic apparatus was inhibited. Furthermore, slightly acidic pHi caused cleavage retardation or inhibition. By counting the number of the eggs at various mitotic stages with time after treating them with the media, it is found that metaphase was persistent and most of the S. mirabilis eggs were arrested at metaphase under the condition of pHi 6.70. It is concluded that at slightly acidic pH, the microtubules in the spindle are stabilized and more microtubules assembled than those in the normal eggs.

On Reproductive Work in Spain: Transnational Adoption, Egg Donation, Surrogacy.

PubMed

Marre, Diana; San Román, Beatriz; Guerra, Diana

2018-01-01

Spain's plummeting fertility since the late twentieth century may seem to reflect a waning desire for children. Nevertheless, reproductive disappointments resulting from gender inequalities cause many Spanish women to postpone motherhood and experience age-related fertility problems. For them, creating a family often becomes possible only through the reproductive labor of other women. Our analysis of transnational adoption, egg donation, and surrogacy in Spain shows how anonymity and altruism play out in these three strategies, with implications for the valuation of women's reproductive work and relationships among reproductive providers, intermediaries, recipients, and the resulting children.

Do Gametes Woo? Evidence for Their Nonrandom Union at Fertilization.

PubMed

Nadeau, Joseph H

2017-10-01

A fundamental tenet of inheritance in sexually reproducing organisms such as humans and laboratory mice is that gametes combine randomly at fertilization, thereby ensuring a balanced and statistically predictable representation of inherited variants in each generation. This principle is encapsulated in Mendel's First Law. But exceptions are known. With transmission ratio distortion, particular alleles are preferentially transmitted to offspring. Preferential transmission usually occurs in one sex but not both, and is not known to require interactions between gametes at fertilization. A reanalysis of our published work in mice and of data in other published reports revealed instances where any of 12 mutant genes biases fertilization, with either too many or too few heterozygotes and homozygotes, depending on the mutant gene and on dietary conditions. Although such deviations are usually attributed to embryonic lethality of the underrepresented genotypes, the evidence is more consistent with genetically-determined preferences for specific combinations of egg and sperm at fertilization that result in genotype bias without embryo loss. This unexpected discovery of genetically-biased fertilization could yield insights about the molecular and cellular interactions between sperm and egg at fertilization, with implications for our understanding of inheritance, reproduction, population genetics, and medical genetics. Copyright © 2017 by the Genetics Society of America.

Observations of turkey eggs stored up to 27 days and incubated for 8 days: embryo developmental stage and weight differences and the differentiation of fertilized from unfertilized germinal discs

USDA-ARS?s Scientific Manuscript database

For logistical reasons, egg storage prior to incubation is a growing practice in the commercial turkey industry. In the following study, 5 groups of eggs each from inseminated and virgin hens were stored for progressively increasing periods of time (5 days or less to 21-27 days) and incubated. At ...

Germline Defects Caused by Smed-boule RNA-Interference Reveal That Egg Capsule Deposition Occurs Independently of Fertilization, Ovulation, Mating, or the Presence of Gametes in Planarian Flatworms

PubMed Central

Steiner, Jessica Kathryne; Tasaki, Junichi; Rouhana, Labib

2016-01-01

Few animals are known to lay eggs in the absence of ovulation or copulation, as it is presumably energetically wasteful and subjected to negative selection. Characterization of Smed-boule, a member of the DAZ family of germline RNA-binding proteins, revealed that egg capsule (or capsule) production and deposition occurs independently of the presence of gametes in the planarian flatworm Schmidtea mediterranea. Reduction of Smed-boule expression by RNA-interference (RNAi) causes ablation of spermatogonial stem cells and the inability of ovarian germline stem cells to undergo oogenesis. Although animals subjected to Smed-boule RNAi lose their gametes and become sterile, they continue to lay egg capsules. Production of sterile capsules is even observed in virgin Smed-boule(RNAi) and control planarians maintained in complete isolation, demonstrating that egg production in S. mediterranea occurs independently of ovulation, fertilization, or mating. Evidence suggests that this is a conserved feature amongst Platyhelminthes, and therefore relevant to the pathology and dissemination of parasitic flatworms. These findings demonstrate that Smed-boule functions at different stages during male and female germline stem cell development, and also demonstrate that egg capsule production by planarian flatworms occurs independently of signals produced by mating or ova. PMID:27149082

Germline Defects Caused by Smed-boule RNA-Interference Reveal That Egg Capsule Deposition Occurs Independently of Fertilization, Ovulation, Mating, or the Presence of Gametes in Planarian Flatworms.

PubMed

Steiner, Jessica Kathryne; Tasaki, Junichi; Rouhana, Labib

2016-05-01

Few animals are known to lay eggs in the absence of ovulation or copulation, as it is presumably energetically wasteful and subjected to negative selection. Characterization of Smed-boule, a member of the DAZ family of germline RNA-binding proteins, revealed that egg capsule (or capsule) production and deposition occurs independently of the presence of gametes in the planarian flatworm Schmidtea mediterranea. Reduction of Smed-boule expression by RNA-interference (RNAi) causes ablation of spermatogonial stem cells and the inability of ovarian germline stem cells to undergo oogenesis. Although animals subjected to Smed-boule RNAi lose their gametes and become sterile, they continue to lay egg capsules. Production of sterile capsules is even observed in virgin Smed-boule(RNAi) and control planarians maintained in complete isolation, demonstrating that egg production in S. mediterranea occurs independently of ovulation, fertilization, or mating. Evidence suggests that this is a conserved feature amongst Platyhelminthes, and therefore relevant to the pathology and dissemination of parasitic flatworms. These findings demonstrate that Smed-boule functions at different stages during male and female germline stem cell development, and also demonstrate that egg capsule production by planarian flatworms occurs independently of signals produced by mating or ova.

Hormonal priming, induction of ovulation and in-vitro fertilization of the endangered Wyoming toad (Bufo baxteri)

PubMed Central

Browne, Robert K; Seratt, Jessica; Vance, Carrie; Kouba, Andrew

2006-01-01

The endangered Wyoming toad (Bufo baxteri) is the subject of an extensive captive breeding and reintroduction program. Wyoming toads in captivity rarely ovulate spontaneously and hormonal induction is used to ovulate females or to stimulate spermiation in males. With hormonal induction, ovulation is unreliable and egg numbers are low. The sequential administration of anovulatory doses of hormones (priming) has increased egg numbers and quality in both anurans and fish. Consequently, we tested the efficacy of a combination of human Chorionic Gonadotrophin (hCG) and Luteinizing Hormone Releasing Hormone analogue (LHRHa) administered as one dose, or two or three sequential doses to Bufo baxteri on egg numbers, fertilization and early embryo development. Spawning toads deposited eggs into Simplified Amphibian Ringers (SAR) solution to enable controlled in-vitro fertilization (IVF) with sperm from hormonally induced male toads. Unprimed females receiving a single mixed normally ovulatory dose of 500 IU hCG plus 4 micrograms of LHRHa produced no eggs. Whereas females primed with this dose and an anovulatory dose (100 IU hCG and 0.8 micrograms of LHRHa) of the same hormones, or primed only with an anovulatory dose, spawned after then receiving an ovulatory dose. Higher total egg numbers were produced with two primings than with one priming. Moreover, two primings produced significantly more eggs from each individual female than one priming. The cleavage rate of eggs was not found to differ between one or two primings. Nevertheless, embryo development with eggs from two primings gave a significantly greater percentage neurulation and swim-up than those from one priming. Of the male toads receiving a single dose of 300 IU hCG, 80% produced spermic urine with the greatest sperm concentration 7 hours post-administration (PA). However, peak sperm motility (95%) was achieved at 5 hours PA and remained relatively constant until declining 20 hours PA. In conclusion, Bufo baxteri egg numbers and quality benefited from sequential priming with LHRHa and hCG whereas spermic urine for IVF was produced from males with a single dose of hCG. The power of assisted reproduction technology in the conservation of endangered amphibians is shown by the release of nearly 2000 tadpoles produced by IVF during this study. PMID:16790071

Short and long-term effects of three neurotoxic insecticides on biological and behavioural attributes of the orb-web spider Alpaida veniliae (Araneae, Araneidae): implications for IPM programs.

PubMed

Benamú, Marco A; Schneider, Marcela I; González, Alda; Sánchez, Norma E

2013-09-01

Soybean pest control in Argentina is done just by chemical control using broad-spectrum pesticides. Alpaida veniliae (Araneae, Araneidae) is one of the most abundant spider species of the orb web weaver guild in soybean, and it is considered a very important polyphagous predator, attacking different insects' families. The objective of this study was to determine if neurotoxic insecticides commonly used in soybean crops and a new active ingredient registered in Argentina (spinosad) adversely affected survival, prey consumption, mating behaviour, web building and reproductive capacity of A. veniliae females, under standard laboratory conditions. Spinosad was the most harmful insecticide due to high acute toxicity, even at lower concentrations than those registered for its field use and for its sublethal effects also. Cypermethrin caused several sublethal effects although its acute toxicity on spider was lower than other insecticides. It reduced prey consumption, affected web building, caused abnormalities in eggs sacs and decreased drastically the fecundity and fertility at sublethal concentrations. Endosulfan did not reduce prey consumption but it affected web building, caused abnormalities in eggs sacs and egg masses, and decreased the fecundity and fertility. Spinosad was also the compound with the most drastic effect on web building, it did not reduce prey consumption and fecundity, but fertility was reduced and abnormalities in egg sacs and egg masses were observed. The use of these insecticides in IPM programs according to their potential toxicity on spider communities is discussed.

Methylxanthines and reproduction.

PubMed

Minelli, Alba; Bellezza, Ilaria

2011-01-01

Reproduction is the process by which organisms create descendants. In human reproduction, two kinds of sex cells, or gametes, are involved. Sperm, the male gamete, and egg egg , or ovum ovum Vedi egg , the female gamete, must meet in the female reproductive system to create a new individual and both the female and the male reproductive systems are essential to the occurrence of reproduction. Scientific reports dealing with the effects of methylxanthines on reproduction are mostly centred on the use of these compounds as phosphodiesterase inhibitors that, by maintaining high intracellular levels of cyclic AMP (cAMP) cyclic AMP , will affect the gametes differently. High cAMP levels will sustain sperm sperm maturation while they hold the oocytes in mitotic arrest. Caffeine caffeine , being the methylxanthine most widely consumed by every segment of the population, has been the subject of greatest interest among health professionals and researchers. Conflicting results still seem to characterize the association between male/female caffeine caffeine consumption in adult life and semen quality/fertility fertility , although moderate daily caffeine consumption of levels up to 400-450 mg/day (5.7-6.4 mg/kg/day in a 70-kg adult) do not seem to be associated with adverse effects, i.e. general toxicity, effects on bone status and calcium balance, cardiovascular effects, behavioural changes, increased incidence of cancer, or effects on male fertility. A clear stimulation of egg-laying by the coffee leaf pest Leucoptera coffeella was recently reported, providing support for the hypothesis that caffeine, in a dose-dependent way, in insects stimulates egg-laying, thus leading to the death of coffee trees.

Participation of the 39-kDa glycoprotein (gp39) of the vitelline envelope of Bufo arenarum eggs in sperm-egg interaction.

PubMed

Barrera, Daniel; Llanos, Ricardo J; Miceli, Dora C

2012-05-01

The acquisition of egg fertilizability in Bufo arenarum takes place during the oviductal transit and during this process the extracellular coelomic envelope (CE) of the eggs is converted into the vitelline envelope (VE). It has been stated that one of the necessary events leading to a fertilizable state is the proteolytic cleavage of CE glycoproteins in the oviductal pars recta by oviductin, a serine protease. Consequently, there is a marked increase in the relative quantity of glycoproteins with 39 (gp39) and 42 kDa (gp42) in the VE. In the present study, sperm-VE binding assays using heat-solubilized biotin-conjugated VE glycoproteins revealed that both gp39 and gp42 have sperm binding capacity. According to this result, our study was focused on gp39, a glycoprotein that we have previously reported as a homologue of mammalian ZPC. For this purpose, rabbit polyclonal antibodies against gp39 were generated at our laboratory. The specificity of the antibodies was confirmed with western blot of VE glycoproteins separated on SDS-PAGE. Immunohistochemical and immunoelectron studies showed gp39 distributed throughout the width of the VE. In addition, immunofluorescence assays probed that gp39 bound to the sperm head. Finally, as an approach to elucidate the possible involvement of gp39 in fertilization, inhibition assays showed that pretreatment of eggs with antibodies against gp39 generated a significant decrease in the fertilization rate. Therefore, our findings suggest that gp39, which is modified by oviductal action, participates as a VE glycoprotein ligand for sperm in Bufo arenarum fertilization.

Consequences of uncontrolled cooling during sterlet (Acipenser ruthenus) sperm cryopreservation on post-thaw motility and fertilizing ability.

PubMed

Horokhovatskyi, Yevhen; Rodina, Marek; Asyabar, Hadiseh Dadras; Boryshpolets, Sergii; Dzyuba, Borys

2017-06-01

The significant influence of the number and position of fish sperm sample straws in uncontrolled cooling devices on post-thaw spermatozoa parameters, such as motility and fertilizing ability, is presented in this study. The two most popular uncontrolled cooling devices were used in this study: a Styrofoam box setup with a polystyrene floating raft on liquid nitrogen and the dry shipper setup with a straw holder. We tested the effect of different quantities of straws (6 or 60) placed on the polystyrene floating raft and the position of the straws in the holder (on the periphery or in the centre). Using these cooling methods, sperm of 10 male sterlets diluted with methanol containing cryoprotective medium was frozen. All temperature changes were recorded by a thermocouple inside the straw, and the thermogram intervals were analysed. Spermatozoa motility was evaluated by video microscopy with integrated computer-assisted sperm analysis software. Fertilization trials were conducted at a 10 5 spermatozoa/egg ratio. Post-thaw spermatozoa parameters, including the percent of motile spermatozoa, curvilinear velocity, velocity according to the smoothed path, linearity of track, beat-cross frequency and fertilization rate, were significantly decreased in the 60-straw floating raft setup in comparison to all of the other cooling methods. The freezing rate between -10 °C and -30 °C was significantly decreased by up to 18.6 ± 0.61 °C/min for the 60-straw floating raft setup in comparison to the other freezing conditions. Considering the above results, efforts to standardize cryopreservation protocols using uncontrolled cooling devices should take into account the amount of straws subjected to freezing. Copyright © 2017. Published by Elsevier Inc.

Distinct sperm nucleus behaviors between genotypic and temperature-dependent sex determination males are associated with replication and expression-related pathways in a gynogenetic fish.

PubMed

Zhu, Yao-Jun; Li, Xi-Yin; Zhang, Jun; Li, Zhi; Ding, Miao; Zhang, Xiao-Juan; Zhou, Li; Gui, Jian-Fang

2018-06-05

Coexistence and transition of diverse sex determination strategies have been revealed in some ectothermic species, but the variation between males caused by different sex determination strategies and the underlying mechanism remain unclear. Here, we used the gynogenetic gibel carp (Carassius gibelio) with both genotypic sex determination (GSD) and temperature-dependent sex determination (TSD) strategies to illustrate this issue. We found out that males of GSD and TSD in gibel carp had similar morphology, testicular histology, sperm structure and sperm vitality. However, when maternal individuals were mated with males of GSD, sperm nucleus swelling and fusing with the female pronucleus were observed in the fertilized eggs. On the contrary, when maternal individuals were mated with males of TSD, sperm nucleus remained in the condensed status throughout the whole process. Subsequently, semen proteomics analysis unveiled that DNA replication and gene expression-related pathways were inhibited in the sperm from males of TSD compared to males of GSD, and most differentially expressed proteins associated with DNA replication, transcription and translation were down-regulated. Moreover, via BrdU incorporation and immunofluorescence detection, male nucleus replication was revealed to be present in the fertilized eggs by the sperm from males of GSD, but absent in the fertilized eggs by the sperm from males of TSD. These findings indicate that DNA replication and gene expression-related pathways are associated with the distinct sperm nucleus development behaviors in fertilized eggs in response to the sperm from males of GSD and TSD. And this study is the first attempt to screen the differences between males determined via GSD and TSD in gynogenetic species, which might give a hint for understanding evolutionary adaption of diverse sex determination mechanisms in unisexual vertebrates.

MALE REPRODUCTIVE PHYSIOLOGY AND THE DEVELOPMENT OF ARTIFICIAL INSEMINATION IN THE MAGELLANIC PENGUIN (SPHENISCUS MAGELLANICUS) USING CHILLED-STORED SEMEN.

PubMed

O'Brien, Justine K; Nollens, Hendrik H; Schmitt, Todd L; Steinman, Karen J; Dubach, Jean M; Robeck, Todd R

2016-03-01

Research was performed to increase our understanding of male Magellanic penguin (Spheniscus magellanicus) reproductive biology and to develop artificial insemination (AI) technology to assist with maintaining the species' genetic diversity. Seminal traits were characterized from seven males with noncontaminated ejaculates (n = 123) displaying high in vitro motion parameters, membrane integrity, and morphology. Seven females were maintained in nest sites that permitted visual, auditory, and tactile contact with their paired male but not copulation for 18.3 ± 2.4 days before egg lay. After cloacal AI (2.6 ± 0.4 inseminations/female) with semen chilled for up to 20.5 hr at 5°C, all females produced one to two fertile eggs, with the first oviposition occurring within 7 days of plasma progesterone concentrations exceeding 0.8 ng/ml. Overall fertility was 91.7%, hatchability was 63.6%, and genetic analyses confirmed that all embryos and hatchlings were sired by AI males. The heterospermic AI design demonstrated that eggs were fertilized by spermatozoa chilled for 1.5-19.8 hr before AI and were laid 4.5-11.5 days post AI. These results contribute new data on Magellanic penguin sperm biology and demonstrate that high fertility rates after AI of chilled semen can be achieved with females remaining in proximity to their paired mate.

Dimethyleacetamide improves the cryosurvivability of Indian red jungle fowl (Gallus gallus murghi) sperm.

PubMed

Rakha, B A; Ansari, M S; Akhter, S; Zafar, Z; Naseer, A; Hussain, I; Santiago-Moreno, J; Blesbois, E

2017-11-01

It was hypothesized that dimethyleacetamide (DMA) can be used as an alternate to glycerol for cryopreservation of Indian red jungle fowl semen. Four concentrations of DMA (4%, 6%, 8% and 10%) in extender were compared with previously optimized cryopreservation protocol based on 20% glycerol (control) for Indian red jungle fowl. Sperm motility, plasma membrane integrity, viability, and acrosome integrity were assessed at the stage of post-dilution, cooling, equilibration, and freeze-thawing. The whole experiment was repeated/replicated for five times independently. Sperm motility, plasma membrane integrity, viability and acrosome integrity were recorded highest (P < 0.05) at post-dilution, cooling, equilibration, and freeze-thawing in extender having 6% DMA compared to control and other experimental extenders. The highest (P < 0.05) recovery rates of all aforementioned parameters were also recorded in extender having 6% DMA; thus, 6% DMA was further compared with control (20% glycerol) for fertility after artificial insemination. Eggs were collected for five days after artificial insemination with semen cryopreserved in extender containing 6% DMA and control. The higher no. of fertilized eggs, fertility, no. of hatched eggs, hatch (%) and hatchability were recorded with semen cryopreserved in extender having 6% DMA compared to control. It is concluded that 6% DMA maintained higher post-thaw quality and fertility of Indian red jungle fowl semen and is a better replacement of glycerol. Copyright © 2017 Elsevier Inc. All rights reserved.

The effect of endoscopic sterilization on reproductive behavior and pair bond maintenance of feral pigeons (Columba livia).

PubMed

Heiderich, E; Failing, K; Lierz, M; Schildger, B

2016-01-01

Problems related to feral pigeons (Columba livia) in cities mainly result from their large numbers due to uncontrolled population growth. The aim of this study was to evaluate whether endoscopic guided sterilization affects the reproductive behavior of feral pigeons under experimental conditions, with the intention of assessing this technique as a potential method for feral pigeon population control. Five groups of four pairs of feral pigeons each were studied from 8 weeks before, to 7 weeks after sterilization. Both the male and female of the first pair of each group were sterilized, in the second pair only the female and in the third pair only the male was sterilized. The fourth pair acted as a control. All eggs laid were candled to assess fertility. Surgical sterilization had minimal effects on behavior and therefore seems not to have impact on possible field application for population control. All pairs maintained their pair bonds and continued to defend their nesting sites against other pigeons. Only one female copulated with a foreign fertile male while her primary partner was debilitated due to surgery, but returned to him as soon as he recovered. All eggs laid more than 5 days after male sterilization were infertile, whereas all control pairs had fertile eggs. Only one fertile clutch was produced, 5 days after the male's sterilization. Therefore it is assumed that males remain fertile for a limited period of time. Endoscopic sterilization seems to be a promising method for field control of feral pigeon populations and sterilization of the male only seems sufficient.

Two-pore channels function in calcium regulation in sea star oocytes and embryos

PubMed Central

Ramos, Isabela; Reich, Adrian; Wessel, Gary M.

2014-01-01

Egg activation at fertilization is an excellent process for studying calcium regulation. Nicotinic acid adenine dinucleotide-phosphate (NAADP), a potent calcium messenger, is able to trigger calcium release, likely through two-pore channels (TPCs). Concomitantly, a family of ectocellular enzymes, the ADP-ribosyl cyclases (ARCs), has emerged as being able to change their enzymatic mode from one of nucleotide cyclization in formation of cADPR to a base-exchange reaction in the generation of NAADP. Using sea star oocytes we gain insights into the functions of endogenously expressed TPCs and ARCs in the context of the global calcium signals at fertilization. Three TPCs and one ARC were found in the sea star (Patiria miniata) that were localized in the cortex of the oocytes and eggs. PmTPCs were localized in specialized secretory organelles called cortical granules, and PmARCs accumulated in a different, unknown, set of vesicles, closely apposed to the cortical granules in the egg cortex. Using morpholino knockdown of PmTPCs and PmARC in the oocytes, we found that both calcium regulators are essential for early embryo development, and that knockdown of PmTPCs leads to aberrant construction of the fertilization envelope at fertilization and changes in cortical granule pH. The calcium signals at fertilization are not significantly altered when individual PmTPCs are silenced, but the timing and shape of the cortical flash and calcium wave are slightly changed when the expression of all three PmTPCs is perturbed concomitantly, suggesting a cooperative activity among TPC isoforms in eliciting calcium signals that may influence localized physiological activities. PMID:25377554

DNA methylation profiles correlated to striped bass sperm fertility

USDA-ARS?s Scientific Manuscript database

Striped bass (Morone saxatilis) spermatozoa are used to fertilize in vitro the eggs of white bass (Morone chrysops) to produce the preferred hybrid for the striped bass aquaculture industry. Currently, only one source of domestic striped bass juveniles are available to growers that are not obtained ...

Sperm Proteasomes Degrade Sperm Receptor on the Egg Zona Pellucida during Mammalian Fertilization

PubMed Central

Zimmerman, Shawn W.; Manandhar, Gaurishankar; Yi, Young-Joo; Gupta, Satish K.; Sutovsky, Miriam; Odhiambo, John F.; Powell, Michael D.; Miller, David J.; Sutovsky, Peter

2011-01-01

Despite decades of research, the mechanism by which the fertilizing spermatozoon penetrates the mammalian vitelline membrane, the zona pellucida (ZP) remains one of the unexplained fundamental events of human/mammalian development. Evidence has been accumulating in support of the 26S proteasome as a candidate for echinoderm, ascidian and mammalian egg coat lysin. Monitoring ZP protein degradation by sperm during fertilization is nearly impossible because those few spermatozoa that penetrate the ZP leave behind a virtually untraceable residue of degraded proteins. We have overcome this hurdle by designing an experimentally consistent in vitro system in which live boar spermatozoa are co-incubated with ZP-proteins (ZPP) solubilized from porcine oocytes. Using this assay, mimicking sperm-egg interactions, we demonstrate that the sperm-borne proteasomes can degrade the sperm receptor protein ZPC. Upon coincubation with motile spermatozoa, the solubilized ZPP, which appear to be ubiquitinated, adhered to sperm acrosomal caps and induced acrosomal exocytosis/formation of the acrosomal shroud. The degradation of the sperm receptor protein ZPC was assessed by Western blotting band-densitometry and proteomics. A nearly identical pattern of sperm receptor degradation, evident already within the first 5 min of coincubation, was observed when the spermatozoa were replaced with the isolated, enzymatically active, sperm-derived proteasomes. ZPC degradation was blocked by proteasomal inhibitors and accelerated by ubiquitin-aldehyde(UBAL), a modified ubiquitin protein that stimulates proteasomal proteolysis. Such a degradation pattern of ZPC is consistent with in vitro fertilization studies, in which proteasomal inhibitors completely blocked fertilization, and UBAL increased fertilization and polyspermy rates. Preincubation of intact zona-enclosed ova with isolated active sperm proteasomes caused digestion, abrasions and loosening of the exposed zonae, and significantly reduced the fertilization/polyspermy rates after IVF, accompanied by en-mass detachment of zona bound sperm. Thus, the sperm borne 26S proteasome is a candidate zona lysin in mammals. This new paradigm has implications for contraception and assisted reproductive technologies in humans, as well as animals. PMID:21383844

Seminal fluid enhances competitiveness of territorial males' sperm in a fish with alternative male reproductive tactics.

PubMed

Poli, Federica; Locatello, Lisa; Rasotto, Maria B

2018-05-29

The most common adaptation to sperm competition in males is represented by an increase in the sperm number and/or quality released at mating, to raise their probability of egg fertilization. However, rapidly mounting evidence highlights that seminal fluid may directly influence the competitive fertilization success of a male by affecting either own and/or rival sperm performances. In the black goby, Gobius niger , an external fertilizer with guard-sneaker mating tactics and high sperm competition level, sneaker males' ejaculates contain less seminal fluid and more sperm, that are also of better quality, than those of territorial males. However, territorial males, gain a higher paternity success inside natural nests. Here, we ask whether the seminal fluid can contribute to territorial males' reproductive success by enhancing their sperm performances and/or by decreasing those of sneaker males. Using sperm and seminal fluid manipulation and in vitro fertilization tests, we found that own seminal fluid influences the velocity and fertilization ability of sperm only in territorial males, making them as faster as those of sneakers and with similar fertilization rate. Moreover, both sneaker and territorial males' sperm remain unaffected by the seminal fluid of rival males. Thus, black goby males respond to the different level of sperm competition faced by differently allocating in sperm and non-sperm components of the ejaculate, with sneakers primarily investing in sperm of intrinsic high quality and territorial males relying on the effect of seminal fluid to increase the lower intrinsic quality of their sperm. © 2018. Published by The Company of Biologists Ltd.

Mice lacking the USP2 deubiquitinating enzyme have severe male subfertility associated with defects in fertilization and sperm motility.

PubMed

Bedard, Nathalie; Yang, Yaoming; Gregory, Mary; Cyr, Daniel G; Suzuki, João; Yu, Xiaomin; Chian, Ri-Cheng; Hermo, Louis; O'Flaherty, Cristian; Smith, Charles E; Clarke, Hugh J; Wing, Simon S

2011-09-01

The ubiquitin-proteasome system plays an important role in spermatogenesis. However, the functions of deubiquitinating enzymes in this process remain poorly characterized. We previously showed that the deubiquitinating enzyme USP2 is induced in late elongating spermatids. To identify its function, we generated mice lacking USP2. Usp2 -/- mice appeared normal, and the weights of major organs, including the testis, did not differ from wild type (Usp2 +/+). However, although the numbers of testicular spermatids and epididymal spermatozoa were normal in Usp2 -/- males, these animals had a severe defect in fertility, yielding only 12% as many offspring as Usp2 +/+ littermates. Spermatogenesis in Usp2 -/- mice was morphologically normal except for the presence of abnormal aggregations of elongating spermatids and formation of multinucleated cells in some tubules. The epididymal epithelium was morphologically normal in Usp2 -/- mice, but some abnormal cells other than sperm were present in the lumen. Usp2 -/- epididymal spermatozoa manifested normal motility when incubated in culture media, but rapidly became immotile when incubated in PBS in contrast to Usp2 +/+ spermatozoa, which largely maintained motility under this condition. Usp2 -/- and +/+ spermatozoa underwent acrosome reactions in vitro with similar frequency. In vitro fertilization assays demonstrated a severe defect in the ability of Usp2 -/- spermatozoa to fertilize eggs. This could be bypassed by intracytoplasmic sperm injection or removal of the zona pellucida, which resulted in fertilization rates similar to that of Usp2 +/+ mice. We demonstrate for the first time, using mouse transgenic approaches, a role for the ubiquitin system in fertilization.

Live Births from Domestic Dog (Canis familiaris) Embryos Produced by In Vitro Fertilization

PubMed Central

Nagashima, Jennifer B.; Sylvester, Skylar R.; Nelson, Jacquelyn L.; Cheong, Soon Hon; Mukai, Chinatsu; Lambo, Colleen; Flanders, James A.; Meyers-Wallen, Vicki N.; Songsasen, Nucharin; Travis, Alexander J.

2015-01-01

Development of assisted reproductive technologies (ART) in the dog has resisted progress for decades, due to their unique reproductive physiology. This lack of progress is remarkable given the critical role ART could play in conserving endangered canid species or eradicating heritable disease through gene-editing technologies—an approach that would also advance the dog as a biomedical model. Over 350 heritable disorders/traits in dogs are homologous with human conditions, almost twice the number of any other species. Here we report the first live births from in vitro fertilized embryos in the dog. Adding to the practical significance, these embryos had also been cryopreserved. Changes in handling of both gametes enabled this progress. The medium previously used to capacitate sperm excluded magnesium because it delayed spontaneous acrosome exocytosis. We found that magnesium significantly enhanced sperm hyperactivation and ability to undergo physiologically-induced acrosome exocytosis, two functions essential to fertilize an egg. Unlike other mammals, dogs ovulate a primary oocyte, which reaches metaphase II on Days 4–5 after the luteinizing hormone (LH) surge. We found that only on Day 6 are oocytes consistently able to be fertilized. In vitro fertilization of Day 6 oocytes with sperm capacitated in medium supplemented with magnesium resulted in high rates of embryo development (78.8%, n = 146). Intra-oviductal transfer of nineteen cryopreserved, in vitro fertilization (IVF)-derived embryos resulted in seven live, healthy puppies. Development of IVF enables modern genetic approaches to be applied more efficiently in dogs, and for gamete rescue to conserve endangered canid species. PMID:26650234

Ejaculate and type of freezing extender affect rates of fertilization of horse oocytes in vitro.

PubMed

Roasa, L M; Choi, Y H; Love, C C; Romo, S; Varner, D D; Hinrichs, K

2007-09-01

In vitro fertilization (IVF) was performed on in vitro-matured equine oocytes in three experiments. Frozen-thawed sperm were prepared using swim-up separation and heparin treatment. In Experiment 1, fertilization was achieved with sperm from only one frozen ejaculate of four obtained from the same stallion. Within this ejaculate, fertilization rates were higher with fresh media, as compared to media held for 6-8 days before use (39.6% versus 7.3%, respectively; P<0.001). The type of bovine serum albumin used affected fertilization rates (4% versus 39.6%; P<0.001). To determine if IVF rates were influenced by factors associated with the freezing process (Experiment 2), a single ejaculate from a second stallion was frozen using eight variations in timing of steps in the freezing protocol. There were no differences among treatments in fertilization rates (range, 0-3%). In Experiment 3, fertilization rates of semen frozen in an extender containing 21.5% egg yolk were lower than fertilization rates of semen from the same ejaculate but frozen with a 3% egg-yolk extender (0% versus 15%, respectively; P<0.01). We inferred that rates of equine IVF with frozen-thawed sperm were influenced by ejaculate, the composition and age of the media used, and freezing extender. To our knowledge, this is the first report of ejaculate or extender differences affecting in vitro fertilization in this species. These factors may help to explain the great variability in fertilization rates reported with equine IVF, both among and within laboratories.

The asymmetry of avian egg-shape: an adaptation for reproduction on dry land

PubMed Central

Mao, Kun-Ming; Murakami, Ayako; Iwasawa, Atsushi; Yoshizaki, Norio

2007-01-01

The present study describes the biological meaning of the asymmetrical shape in avian reproduction using quail. During the incubation of eggs, water was gradually lost and the air chamber which appeared in between the inner and outer shell membranes at the blunt end expanded, so that the angle made by the long egg-axis and the horizontal line increased, presumably because the centre of gravity of the egg contents moved toward the sharp end. The increase in angle occurred in both fertile and infertile eggs, suggesting that this phenomenon occurs irrespective of fertility and is due to the asymmetrical shape. The increase in the volume of the air chamber resulted in an increase in the area of the inner shell membrane at the chamber to satisfy the amount of gas exchange needed by the developing embryo for better hatching. We isolated a 300-kDa protein from the inner shell membrane. It was produced by cells in the luminal epithelium of the oviductal isthmus and was found in the cortex of the fibres of shell membranes and a lining surrounding the air chamber. The lining comprised a medial layer between the inner and outer shell membranes in uterine eggs. The asymmetrical ellipsoid produces the air chamber at the blunt end of the avian egg during its sojourn in the oviductal isthmus, to maintain the blunt end up after oviposition and to raise that end during incubation in a dry environment, leading to high hatchability. PMID:17523938

Ca2+ release triggered by nicotinate adenine dinucleotide phosphate in intact sea urchin eggs.

PubMed Central

Perez-Terzic, C M; Chini, E N; Shen, S S; Dousa, T P; Clapham, D E

1995-01-01

Nicotinate adenine dinucleotide phosphate (NAADP) was recently identified [Lee and Aarhus (1995) J. Biol. Chem. 270, 2152-2157; Chini, Beers and Dousa (1995) J. Biol. Chem. 270, 3116-3223] as a potent Ca(2+)-releasing agent in sea urchin egg homogenates. NAADP triggered Ca2+ release by a mechanism that was distinct from inositol 1,4,5-trisphosphate (InsP3)- and cyclic ADP-ribose (cADPR)-induced Ca2+ release. When NAADP was microinjected into intact sea urchin eggs it induced a dose-dependent increase in cytoplasmic free Ca2+ which was independent of the extracellular [Ca2+]. The Ca2+ waves elicited by microinjections of NAADP originated at the site of injection and swept across the cytosol. As previously found in sea urchin egg homogenates, NAADP-induced Ca2+ release in intact eggs was not blocked by heparin or by prior desensitization to InsP3 or cADPR. Thio-NADP, a specific inhibitor of the NAADP-induced Ca2+ release in sea urchin homogenates [Chini, Beers and Dousa (1995) J. Biol. Chem. 270, 3116-3223] blocked NAADP (but not InsP3 or cADPR) injection-induced Ca2+ release in intact sea urchin eggs. Finally, fertilization of sea urchin eggs abrogated subsequent NAADP-induced Ca2+ release, suggesting that the NAADP-sensitive Ca2+ pool may participate in the fertilization response. This study demonstrates that NAADP acts as a selective Ca(2+)-releasing agonist in intact cells. Images Figure 2 PMID:8554544

Behavior of centrosomes during fertilization and cell division in mouse oocytes and in sea urchin eggs

NASA Technical Reports Server (NTRS)

Schatten, Heide; Schatten, Gerald; Balczon, Ron; Simerly, Calvin; Mazia, Daniel

1986-01-01

The behavior of centrosomes during the stages of fertilization and cell division in mouse oocytes and in sea urchin eggs was monitored in an immunofluorescence microscope, using autoimmune centrosomal antiserum derived from a patient with scleroderma to label the centrosomal material. These observations showed that centrosomes reproduce during the interphase and aggregate and separate during cell mitosis. Results supported the hypothesis of Mazia (1984), who proposed that centrosomes are 'flexible bodies'. It was also found that, while the sea urchin centrosomes are paternally inherited as was initially proposed by Bovery (1904), the mouse centrosomes are of maternal origin.

Establishment of polarities in the oocyte of Xenopus laevis: the provisional axial symmetry of the full-grown oocyte of Xenopus laevis.

PubMed

Ubbels, G A

1997-04-01

We aimed at understanding of formation and function of the "Nieuwkoop Centre" in embryonic pattern formation. Discussed are data on genesis of cytoplasmic localizations in ovarian oocytes, transient modifications of cytoskeletal structures creating cytoplasmic asymmetries in fertilized eggs, the axis determining "vegetal cortical rotation" and fate of distinct cells, as shown by injection of specific molecular markers into particular blastomeres at specific times. Egg rotation and centrifugation suggested that sperm that gravity cooperate in symmetrization of the axially symmetrical anuran egg. After fertilization in space or in a fast rotating clinostate, axis formation and embryonic development were normal although the blastocoel was transiently abnormal. Normal tadpoles came back on Earth after ovulation, fertilization and culture in space. They metamorphosed normally and got healthy Earth-born F1 offspring. We conclude that neither sperm nor gravity are required for determination of the bilateral symmetry in the embryo of Xenopus laevis. In normal development sperm and gravity, either alone or in collaboration, may overrule an initial bilaterality inherent to, the full-grown oocyte, residing in some still unidentified component(s)/or mechanisms.

Embryonic Cleavage Cycles: How Is a Mouse Like a Fly?

PubMed Central

O’Farrell, Patrick H.; Stumpff, Jason; Su, Tin Tin

2009-01-01

The evolutionary advent of uterine support of embryonic growth in mammals is relatively recent. Nonetheless, striking differences in the earliest steps of embryogenesis make it difficult to draw parallels even with other chordates. We suggest that use of fertilization as a reference point misaligns the earliest stages and masks parallels that are evident when development is aligned at conserved stages surrounding gastrulation. In externally deposited eggs from representatives of all the major phyla, gastrulation is preceded by specialized extremely rapid cleavage cell cycles. Mammals also exhibit remarkably fast cell cycles in close association with gastrulation, but instead of beginning development with these rapid cycles, the mammalian egg first devotes itself to the production of extraembryonic structures. Previous attempts to identify common features of cleavage cycles focused on post-fertilization divisions of the mammalian egg. We propose that comparison to the rapid peri-gastrulation cycles is more appropriate and suggest that these cycles are related by evolutionary descent to the early cleavage stages of embryos such as those of frog and fly. The deferral of events in mammalian embryogenesis might be due to an evolutionary shift in the timing of fertilization. PMID:14711435

Diploid male dynamics under different numbers of sexual alleles and male dispersal abilities.

PubMed

Faria, Luiz R R; Soares, Elaine Della Giustina; Carmo, Eduardo do; Oliveira, Paulo Murilo Castro de

2016-09-01

Insects in the order Hymenoptera (bees, wasps and ants) present an haplodiploid system of sexual determination in which fertilized eggs become females and unfertilized eggs males. Under single locus complementary sex-determination (sl-CSD) system, the sex of a specimen depends on the alleles at a single locus: when diploid, an individual will be a female if heterozygous and male if homozygous. Significant diploid male (DM) production may drive a population to an extinction scenario called "diploid male vortex". We aimed at studying the dynamics of populations of a sl-CSD organism under several combinations of two parameters: male flight abilities and number of sexual alleles. In these simulations, we evaluated the frequency of DM and a genetic diversity measure over 10,000 generations. The number of sexual alleles varied from 10 to 100 and, at each generation, a male offspring might fly to another random site within a varying radius R. Two main results emerge from our simulations: (i) the number of DM depends more on male flight radius than on the number of alleles; (ii) in large geographic regions, the effect of males flight radius on the allelic diversity turns out much less pronounced than in small regions. In other words, small regions where inbreeding normally appears recover genetic diversity due to large flight radii. These results may be particularly relevant when considering the population dynamics of species with increasingly limited dispersal ability (e.g., forest-dependent species of euglossine bees in fragmented landscapes).

Embryo Development inside Female Salamander (Ambystoma jeffersonianum-laterale) Prior to Egg Laying

PubMed Central

Charney, Noah D.; Castorino, John J.; Dobro, Megan J.; Steely, Sarah L.

2014-01-01

The length of embryo retention prior to oviposition is a critical evolutionary trait. In all oviparous salamanders, which include the vast majority of species in the order, fertilization is thought to occur at the time of egg laying. Embryos then enter the first cleavage stage several hours after being deposited. This pattern holds for previously studied individuals in the Ambystoma jeffersonianum-laterale complex. Here, we document an instance in which a female Ambystoma jeffersonianum-laterale was carrying embryos internally that had already reached stage 10 of development. Development likely began several days prior to the start of migration to the breeding pond. This is the first such record for any egg-laying salamander, and suggests a degree of plasticity in the timing of fertilization and development not previously recognized. Further work is needed to ascertain the prevalence, mechanics, and evolutionary significance of this phenomenon. PMID:24651275

Telescience testbed experiments for biomedical studies: fertilization potential recording of amphibian eggs using tele-manipulation under stereoscopic vision.

PubMed

Watanabe, S; Tanaka, M; Wada, Y; Suzuki, H; Takagi, S; Mori, S; Fukai, K; Kanazawa, Y; Takagi, M; Hirakawa, K; Ogasawara, K; Tsumura, K; Ogawa, K; Matsumoto, K; Nagaoka, S; Suzuki, T; Shimura, D; Yamashita, M; Nishio, S

1994-07-01

The telescience testbed experiments were carried out to test and investigate the tele-manipulation techniques in the intracellular potential recording of amphibian eggs. Implementation of telescience testbed was set up in the two separated laboratories of the Tsukuba Space center of NASDA, which were connected by tele-communication links. Manipulators respective for a microelectrode and a sample stage of microscope were moved by computers, of which command signals were transmitted from a computer in a remote control room. The computer in the control room was operated by an investigator (PI) who controlled the movement of each manipulator remotely. A stereoscopic vision of the microscope image were prepared by using a head mounted display (HMD) and were indispensable to the intracellular single cell recording. The fertilization potential of amphibian eggs was successfully obtained through the remote operating system.

Sequence-Specific Interaction between the Disintegrin Domain of Mouse ADAM 3 and Murine Eggs: Role of β1 Integrin-associated Proteins CD9, CD81, and CD98

PubMed Central

Takahashi, Yuji; Bigler, Dora; Ito, Yasuhiko; White, Judith M.

2001-01-01

ADAM 3 is a sperm surface glycoprotein that has been implicated in sperm-egg adhesion. Because little is known about the adhesive activity of ADAMs, we investigated the interaction of ADAM 3 disintegrin domains, made in bacteria and in insect cells, with murine eggs. Both recombinant proteins inhibited sperm-egg binding and fusion with potencies similar to that which we recently reported for the ADAM 2 disintegrin domain. Alanine scanning mutagenesis revealed a critical importance for the glutamine at position 7 of the disintegrin loop. Fluorescent beads coated with the ADAM 3 disintegrin domain bound to the egg surface. Bead binding was inhibited by an authentic, but not by a scrambled, peptide analog of the disintegrin loop. Bead binding was also inhibited by the function-blocking anti-α6 monoclonal antibody (mAb) GoH3, but not by a nonfunction blocking anti-α6 mAb, or by mAbs against either the αv or β3 integrin subunits. We also present evidence that in addition to the tetraspanin CD9, two other β1-integrin-associated proteins, the tetraspanin CD81 as well as the single pass transmembrane protein CD98 are expressed on murine eggs. Antibodies to CD9 and CD98 inhibited in vitro fertilization and binding of the ADAM 3 disintegrin domain. Our findings are discussed in terms of the involvement of multiple sperm ADAMs and multiple egg β1 integrin-associated proteins in sperm-egg binding and fusion. We propose that an egg surface “tetraspan web” facilitates fertilization and that it may do so by fostering ADAM–integrin interactions. PMID:11294888

Sequence-specific interaction between the disintegrin domain of mouse ADAM 3 and murine eggs: role of beta1 integrin-associated proteins CD9, CD81, and CD98.

PubMed

Takahashi, Y; Bigler, D; Ito, Y; White, J M

2001-04-01

ADAM 3 is a sperm surface glycoprotein that has been implicated in sperm-egg adhesion. Because little is known about the adhesive activity of ADAMs, we investigated the interaction of ADAM 3 disintegrin domains, made in bacteria and in insect cells, with murine eggs. Both recombinant proteins inhibited sperm-egg binding and fusion with potencies similar to that which we recently reported for the ADAM 2 disintegrin domain. Alanine scanning mutagenesis revealed a critical importance for the glutamine at position 7 of the disintegrin loop. Fluorescent beads coated with the ADAM 3 disintegrin domain bound to the egg surface. Bead binding was inhibited by an authentic, but not by a scrambled, peptide analog of the disintegrin loop. Bead binding was also inhibited by the function-blocking anti-alpha6 monoclonal antibody (mAb) GoH3, but not by a nonfunction blocking anti-alpha6 mAb, or by mAbs against either the alphav or beta3 integrin subunits. We also present evidence that in addition to the tetraspanin CD9, two other beta1-integrin-associated proteins, the tetraspanin CD81 as well as the single pass transmembrane protein CD98 are expressed on murine eggs. Antibodies to CD9 and CD98 inhibited in vitro fertilization and binding of the ADAM 3 disintegrin domain. Our findings are discussed in terms of the involvement of multiple sperm ADAMs and multiple egg beta1 integrin-associated proteins in sperm-egg binding and fusion. We propose that an egg surface "tetraspan web" facilitates fertilization and that it may do so by fostering ADAM-integrin interactions.

Marine gametes in a changing ocean: Impacts of climate change stressors on fecundity and the egg.

PubMed

Foo, Shawna A; Byrne, Maria

2017-07-01

In marine invertebrates, the environmental history of the mother can influence fecundity and egg size. Acclimation of females in climate change stressors, increased temperature and low pH, results in a decrease in egg number and size in many taxa, with the exception of cephalopods, where eggs increase in size. With respect to spawned eggs, near future levels of ocean acidification can interfere with the egg's block to polyspermy and intracellular pH. Reduction of the extracellular egg jelly coat seen in low pH conditions has implications for impaired egg function and fertilization. Some fast generation species (e.g. copepods, polychaetes) have shown restoration of female reproductive output after several generations in treatments. It will be important to determine if the changes to egg number and size induced by exposure to climate change stressors are heritable. Copyright © 2017 Elsevier Ltd. All rights reserved.

Translatome analysis at the egg-to-embryo transition in sea urchin

PubMed Central

Chassé, Héloïse; Aubert, Julie; Boulben, Sandrine; Le Corguillé, Gildas; Corre, Erwan; Cormier, Patrick

2018-01-01

Abstract Early embryogenesis relies on the translational regulation of maternally stored mRNAs. In sea urchin, fertilization triggers a dramatic rise in translation activity, necessary for the onset of cell division. Here, the full spectrum of the mRNAs translated upon fertilization was investigated by polysome profiling and sequencing. The translatome of the early sea urchin embryo gave a complete picture of the polysomal recruitment dynamics following fertilization. Our results indicate that only a subset of maternal mRNAs were selectively recruited onto polysomes, with over-represented functional categories in the translated set. The increase in translation upon fertilization depends on the formation of translation initiation complexes following mTOR pathway activation. Surprisingly, mTOR pathway inhibition differentially affected polysomal recruitment of the newly translated mRNAs, which thus appeared either mTOR-dependent or mTOR-independent. Therefore, our data argue for an alternative to the classical cap-dependent model of translation in early development. The identification of the mRNAs translated following fertilization helped assign translational activation events to specific mRNAs. This translatome is the first step to a comprehensive analysis of the molecular mechanisms governing translation upon fertilization and the translational regulatory networks that control the egg-to-embryo transition as well as the early steps of embryogenesis. PMID:29660001

Translatome analysis at the egg-to-embryo transition in sea urchin.

PubMed

Chassé, Héloïse; Aubert, Julie; Boulben, Sandrine; Le Corguillé, Gildas; Corre, Erwan; Cormier, Patrick; Morales, Julia

2018-05-18

Early embryogenesis relies on the translational regulation of maternally stored mRNAs. In sea urchin, fertilization triggers a dramatic rise in translation activity, necessary for the onset of cell division. Here, the full spectrum of the mRNAs translated upon fertilization was investigated by polysome profiling and sequencing. The translatome of the early sea urchin embryo gave a complete picture of the polysomal recruitment dynamics following fertilization. Our results indicate that only a subset of maternal mRNAs were selectively recruited onto polysomes, with over-represented functional categories in the translated set. The increase in translation upon fertilization depends on the formation of translation initiation complexes following mTOR pathway activation. Surprisingly, mTOR pathway inhibition differentially affected polysomal recruitment of the newly translated mRNAs, which thus appeared either mTOR-dependent or mTOR-independent. Therefore, our data argue for an alternative to the classical cap-dependent model of translation in early development. The identification of the mRNAs translated following fertilization helped assign translational activation events to specific mRNAs. This translatome is the first step to a comprehensive analysis of the molecular mechanisms governing translation upon fertilization and the translational regulatory networks that control the egg-to-embryo transition as well as the early steps of embryogenesis.

Sperm depletion in singly mated females of the Mexican Fruit Fly (Diptera: Tephritidae)

USDA-ARS?s Scientific Manuscript database

Female Mexican fruit flies, or mexflies, have the capacity to produce more than a thousand eggs over their lifetime but fertility of the eggs will depend on the female’s capacity to store semen and/or to replenish semen through remating. The two parameters are interrelated in that sexual receptivity...

Replacing egg yolk with soybean lecithin in the cryopreservation of stallion semen.

PubMed

Papa, Frederico Ozanam; Felício, Gabriel Barcelos; Melo-Oña, Cely Marini; Alvarenga, Marco Antonio; De Vita, Bruna; Trinque, Cássio; Puoli-Filho, José Nicolau P; Dell'Aqua, José Antonio

2011-11-01

The objective of this study was to determine whether replacing the egg yolk with soybean lecithin in the Botu-Crio® cryodiluent would maintain the fertility of cryopreserved stallion sperm. Two experiments were performed to evaluate cell freezability. In experiment 1, sperm from 15 stallions were frozen in Botu-Crio® (BC) or Botu-Crio® which contained 45g/L soybean lecithin (BCLS45) in place of the egg yolk. In experiment 2, we compared different concentrations of soybean lecithin: 0, 10.0, 12.5, 15.0, 17.5 and 20.0g/L (BC, BCLS10, BCLS12.5, BCLS17.5 and BCLS20, respectively). In experiment 1, sperm frozen in BC and BCLS45 exhibited similar (P>0.05) percentages of total motile sperm (61% and 61%, respectively); progressively motile sperm (27% and 27%, respectively) and sperm with intact plasma membranes (IMP; 53% and 57%, respectively). Similarly, sperm frozen in BC or BC containing any concentration of soybean lecithin maintained similar (P>0.05) percentages of total motile sperm (61-68%) and progressively motile sperm (27-31%). In the first fertility trial, we used cryopreserved semen from a single stallion was inseminated into mares. The semen from the sperm that were frozen in BC diluent resulted in a higher fertility rate (66%, 16/24) compared to the sperm that were frozen in BCLS45 diluent (17%, 5/29; P<0.01). Similarly, in a second fertility trial, the mares that were inseminated with the sperm that were frozen in BC diluent exhibited a higher fertility rate (66%, 16/24) compared to the mares that were inseminated with the sperm that were frozen in BCLS20 (40%, 10/25; P<0.05). Finally, in a third trial, the sperm that were frozen in BC resulted in a higher fertility rate in mares (75%, 18/24) compared to the sperm that were frozen in BCLS10 (41%, 10/24; P<0.05). Although replacing the egg yolk in the BC cryodiluent with soybean lecithin provided similar laboratory results for stallion sperm, after cryopreservation, the sperm that was frozen with soybean lecithin in the diluent correlated with lower fertility rates. Based on these results, we concluded that the use of BCLS can be used as an alternative diluent for cryopreserving stallion sperm. However, the resulting reduced fertility rate is a matter of concern. Further studies are necessary to clarify the reasons for this decrease in fertility and to determine the optimal lecithin concentration for diluents to freeze stallion sperm. Copyright © 2011 Elsevier B.V. All rights reserved.

Autoradiographic visualization of the mouse egg's sperm receptor bound to sperm

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bleil, J.D.; Wassarman, P.M.

1986-04-01

The extracellular coat, or zona pellucida, of mammalian eggs contains species-specific receptors to which sperm bind as a prelude to fertilization. In mice, ZP3, one of only three zona pellucida glycoproteins, serves as sperm receptor. Acrosome-intact, but not acrosome-reacted, mouse sperm recognize and interact with specific O-linked oligosaccharides of ZP3 resulting in sperm-egg binding. Binding, in turn, causes sperm to undergo the acrosome reaction; a membrane fusion event that results in loss of plasma membrane at the anterior region of the head and exposure of inner acrosomal membrane with its associated acrosomal contents. Bound, acrosome-reacted sperm are able to penetratemore » the zona pellucida and fuse with the egg's plasma membrane (fertilization). In the present report, we examined binding of radioiodinated, purified, egg ZP3 to both acrosome intact and acrosome reacted sperm by whole-mount autoradiography. Silver grains due to bound 125I-ZP3 were found localized to the acrosomal cap region of heads of acrosome-reacted sperm. Under the same conditions, 125I-fetuin bound at only background levels to heads of both acrosome-intact and -reacted sperm, and 125I-ZP2, another zona pellucida glycoprotein, bound preferentially to acrosome-reacted sperm. These results provide visual evidence that ZP3 binds preferentially and specifically to heads of acrosome intact sperm; properties expected of the mouse egg's sperm receptor.« less

Phosphoproteomic network analysis in the sea urchin Strongylocentrotus purpuratus reveals new candidates in egg activation.

PubMed

Guo, Hongbo; Garcia-Vedrenne, Ana Elisa; Isserlin, Ruth; Lugowski, Andrew; Morada, Anthony; Sun, Alex; Miao, Yishen; Kuzmanov, Uros; Wan, Cuihong; Ma, Hongyue; Foltz, Kathy; Emili, Andrew

2015-12-01

Fertilization triggers a dynamic symphony of molecular transformations induced by a rapid rise in intracellular calcium. Most prominent are surface alterations, metabolic activation, cytoskeletal reorganization, and cell-cycle reentry. While the activation process appears to be broadly evolutionarily conserved, and protein phosphorylation is known to play a key role, the signaling networks mediating the response to fertilization are not well described. To address this gap, we performed a time course phosphoproteomic analysis of egg activation in the sea urchin Strongylocentrotus purpuratus, a system that offers biochemical tractability coupled with exquisite synchronicity. By coupling large-scale phosphopeptide enrichment with unbiased quantitative MS, we identified striking changes in global phosphoprotein patterns at 2- and 5-min postfertilization as compared to unfertilized eggs. Overall, we mapped 8796 distinct phosphosite modifications on 2833 phosphoproteins, of which 15% were differentially regulated in early egg activation. Activated kinases were identified by phosphosite mapping, while enrichment analyses revealed conserved signaling cascades not previously associated with egg activation. This work represents the most comprehensive study of signaling associated with egg activation to date, suggesting novel mechanisms that can be experimentally tested and providing a valuable resource for the broader research community. All MS data have been deposited in the ProteomeXchange with identifier PXD002239 (http://proteomecentral.proteomexchange.org/dataset/PXD002239). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Gene banking of the neotropical fish Leporinus obtusidens (Valenciennes, 1836): a protocol to freeze its sperm in the field.

PubMed

Taitson, P F; Chami, E; Godinho, H P

2008-05-01

A practical sperm cryopreservation protocol using a dry-shipper and a diluent of simple composition is described for the neotropical fish Leporinus obtusidens (Valenciennes, 1836). The cooling rate of the dry-shipper and its period of useful time, established under laboratory conditions, were respectively 25.7-30.8 degrees C/min (between 0 and -60 degrees C) and 9 days after charging. Sperm donors were selected on the basis of their hyperemic genital papilla and the ability to ooze milt under gentle manual pressure, during the reproductive months of November to January. Milt volume (1.3+/-0.3 mL; n=9 fish), fresh sperm motility rate (93.3+/-2.5%; n=6 fish), and sperm concentration (10.9+/-3.0 x 10(9)spermatozoa/mL of milt) were obtained. The sperm cryopreservation experiments were conducted with the following cryoprotectants (all at 10%, before mixing with milt): dimethyl sulphoxide (DMSO; n=10 fish), methanol (n=6 fish), propanediol (n=6 fish) and ethylene glycol (n=5 fish). Glucose (5%) and hen's egg yolk (10%) made up the diluents containing DMSO, ethylene glycol or propanediol. Milk powder (10%) replaced hen's egg yolk in the diluent containing methanol. Distilled water (up to 100%) completed the diluent solutions. Milt freezing (in 0.5-mL straws) was performed in the dry-shipper after 1:5 (milt:diluent) dilution. Thawed sperm cryopreserved in DMSO-containing diluent and activated by 119 mM NaHCO(3) gave the highest motility rate (62+/-14%). The fertilizing capacity of L. obtusidens sperm was tested using the combination of DMSO-containing diluent as the cryoprotectant and 119 mM NaHCO(3) as the activating solution. Oocytes were obtained from artificial spawning and fertilized with different proportions of spermatozoa. The greatest rate of fertilization (74%) occurred when the ratio of about 112,000 motile spermatozoa:oocyte was used. Thus, a protocol to freeze L. obtusidens sperm can be elaborated as follows. Milt (<1.5 mL fish(-1)) was readily available only in November to January; a simple solution, composed of 10% DMSO (concentration before adding milt), 5% glucose, and 10% hen yolk egg, in distilled water, was used as sperm diluent; cooling rate of 25-30 degrees C/min, yielded in a portable dry-shipper, was adequate to freeze diluted milt (1:5; milt:diluent), in 5-mL straws; about 112,000 thawed motile spermatozoa:oocyte activated by 119 mM NaHCO(3) assured a fertilization rate of 74%.

The impact of six insecticides commonly used in control of agricultural pests on the generalist predator Hippodamia convergens (Coleoptera: Coccinellidae).

PubMed

Santos, Kenia Fernanda Aguiar; Zanuzo Zanardi, Odimar; de Morais, Matheus Rovere; Jacob, Cynthia Renata Oliveira; de Oliveira, Monique Bárbara; Yamamoto, Pedro Takao

2017-11-01

Hippodamia convergens is an important predator found in different agroecosystems. We evaluated the impacts of six insecticides on eggs, larvae and adults of this predator. For eggs, all insecticides reduced larval hatching rates, but did not affect egg duration. Chlorpyrifos and phosmet reduced larval survival; and chlorpyrifos, etofenprox and phosmet prolonged the larva development time. The survival and duration of pupae were not affected by all insecticides tested. Chlorpyrifos reduced fecundity, fertility and longevity when eggs were sprayed. For first-instar larvae, chlorpyrifos, etofenprox, phosmet and imidacloprid caused 100% mortality, while azadirachtin and thiamethoxam caused 35.0 and 52.7% mortality, respectively. However, azadirachtin and thiamethoxam did not affect the other biological parameters of the predator. In adults, chlorpyrifos, etofenprox and phosmet reduced adult survival. Chlorpyrifos, etofenprox, and phosmet reduced fecundity and longevity, but did not affect fertility. Azadirachtin, imidacloprid and thiamethoxam did not affect fecundity, fertility or longevity. Based on demographic parameters, all insecticides reduced the net reproductive rate (R o ), intrinsic rate of increase (r) and finite rate of increase (λ) of the predator when eggs were treated directly. Azadirachtin, chlorpyrifos, etofenprox and phosmet increased the mean generation time (T), while the effects of imidacloprid and thiamethoxam were similar to the control. When first-instar larvae were treated, azadirachtin and thiamethoxam reduced the R o , r and λ. Thiamethoxam increased the T value, while the effects of the other insecticides were similar to the control. These insecticides should be used with caution, in order to reduce their harmful effects on the predator in agroecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

The role of HIRA and maternal histones in sperm nucleus decondensation in the gibel carp and color crucian carp.

PubMed

Zhao, Zhan-Ke; Li, Wei; Wang, Meng-Yu; Zhou, Li; Wang, Jia-Lin; Wang, Yu-Feng

2011-02-01

The histone H3.3 chaperone HIRA is essential for chromatin assembly during male pronucleus formation in Drosophila. However, the role of HIRA during fertilization in vertebrates remains unclear. The gibel carp (Carassius auratus gibelio) is a unique gynogenetic crucian carp (gyno-carp). Heterologous sperm nuclei cannot decondense when incorporated in the egg, thus the eggs produce a clonal lineage of all females by typical gynogenesis. In contrast, after entering the egg, homologous sperm can undergo decondensation and sexual reproduction is activated, which may produce both female and male offspring. Therefore, this fish is a useful model for studying the mechanisms of fertilization. Herein, we first compared HIRA expression during embryogenesis between gyno-carp and the gonochoristic color crucian carp (Carassius auratus; gono-carp). In gono-carp, a dramatic reduction of HIRA protein occurs shortly after fertilization, whereas HIRA protein is consistently expressed during embryogenesis of gyno-carp. Next, we used immunodepletion and an in vitro sperm decondensation system, and found that complete removal of HIRA inhibited sperm decondensation in both of the fish. Immunofluorescence localization showed that in the condensed sperm nuclei of gono-carp incubated in gyno-carp egg extracts, HIRA was detected, but neither the histone H2A variant H2af1o nor acetylated histone H4 was observed. These results suggest that HIRA may be a critical factor required for sperm nucleus decondensation, while the defect in deposition of some maternal histones in the sperm nucleus could be one reason why heterologous sperm cannot decondense in the gibel carp egg. Copyright © 2011 Wiley-Liss, Inc.

Lateral mobility of plasma membrane lipids in Xenopus eggs: regional differences related to animal/vegetal polarity become extreme upon fertilization.

PubMed

Dictus, W J; van Zoelen, E J; Tetteroo, P A; Tertoolen, L G; de Laat, S W; Bluemink, J G

1984-01-01

Regional differences in the lateral mobility properties of plasma membrane lipids have been studied in unfertilized and fertilized Xenopus eggs by fluorescence photobleaching recovery (FPR) measurements. Out of a variety of commonly used lipid probes only the aminofluorescein-labeled fatty acids HEDAF (5-(N-hexadecanoyl)-aminofluorescein) and TEDAF (5-(N-tetradecanoyl)-aminofluorescein) appear to partition into the plasma membrane. Under all experimental conditions used these molecules show partial recovery upon photobleaching indicating the existence of lipidic microdomains. In the unfertilized egg the mobile fraction of plasma membrane lipids (approximately 50%) has a fivefold smaller lateral diffusion coefficient (D = 1.5 X 10(-8) cm2/sec) in the animal than in the vegetal plasma membrane (D = 7.6 X 10(-8) cm2/sec). This demonstrates the presence of an animal/vegetal polarity within the Xenopus egg plasma membrane. Upon fertilization this polarity is strongly (greater than 100X) enhanced leading to the formation of two distinct macrodomains within the plasma membrane. At the animal side of the egg lipids are completely immobilized on the time scale of FPR measurements (D less than 10(-10) cm2/sec), whereas at the vegetal side D is only slightly reduced (D = 4.4 X 10(-8) cm2/sec). The immobilization of animal plasma membrane lipids, which could play a role in the polyspermy block, probably arises by the fusion of cortical granules which are more numerous here. The transition between the animal and the vegetal domain is sharp and coincides with the boundary between the presumptive ecto- and endoderm. The role of regional differences in the plasma membrane is discussed in relation to cell diversification in early development.

Postmating sexual selection and the enigmatic jawed genitalia of Callosobruchus subinnotatus

PubMed Central

Rönn, Johanna Liljestrand; Schilthuizen, Menno; Arnqvist, Göran

2017-01-01

ABSTRACT Insect genitalia exhibit rapid divergent evolution. Truly extraordinary structures have evolved in some groups, presumably as a result of postmating sexual selection. To increase our understanding of this phenomenon, we studied the function of one such structure. The male genitalia of Callosobruchus subinnotatus (Coleoptera: Bruchinae) contain a pair of jaw-like structures with unknown function. Here, we used phenotypic engineering to ablate the teeth on these jaws. We then experimentally assessed the effects of ablation of the genital jaws on mating duration, ejaculate weight, male fertilization success and female fecundity, using a double-mating experimental design. We predicted that copulatory wounding in females should be positively related to male fertilization success; however, we found no significant correlation between genital tract scarring in females and male fertilization success. Male fertilization success was, however, positively related to the amount of ejaculate transferred by males and negatively related to female ejaculate dumping. Ablation of male genital jaws did not affect male relative fertilization success but resulted in a reduction in female egg production. Our results suggest that postmating sexual selection in males indeed favors these genital jaws, not primarily through an elevated relative success in sperm competition but by increasing female egg production. PMID:28583926

rab3 mediates cortical granule exocytosis in the sea urchin egg.

PubMed

Conner, S; Wessel, G M

1998-11-15

Egg activation at fertilization in the sea urchin results in the exocytosis of approximately 15,000 cortical granules that are docked at the plasma membrane. Previously, we reported that several integral membrane proteins modeled in the SNARE hypothesis, synaptotagmin, VAMP, and syntaxin, in addition to a small GTPase of the ras superfamily, rab3, were present on cortical granules (Conner, S., Leaf, D., and Wessel, G., Mol. Reprod. Dev. 48, 1-13, 1997). Here we report that rab3 is associated with cortical granules throughout oogenesis, during cortical granule translocation, and while docked at the egg plasma membrane. Following cortical granule exocytosis, however, rab3 reassociates with a different population of vesicles, at least some of which are of endocytic origin. Because of its selective association with cortical granules in eggs and oocytes, we hypothesize that rab3 functions in cortical granule exocytosis. To test this hypothesis, we used a strategy of interfering with rab3 function by peptide competition with its effector domain, a conserved region within specific rab types. We first identified the effector domain sequence in Lytechinus variegatus eggs and find the sequence 94% identical to the effector domain of rab3 in Stronglocentrotus purpuratus. Then, with synthetic peptides to different regions of the rab3 protein, we find that cortical granule exocytosis is inhibited in eggs injected with effector domain peptides, but not with peptides from the hypervariable region or with a scrambled effector peptide. Additionally, effector-peptide-injected eggs injected with IP3 are blocked in their ability to exocytose cortical granules, suggesting that the inhibition is directly on the membrane fusion event and not the result of interference with the signal transduction mechanism leading to calcium release. We interpret these results to mean that rab3 functions in the regulation of cortical granule exocytosis following vesicle docking. Copyright 1998 Academic Press.

Identification and quantification of pathogenic helminth eggs using a digital image system.

PubMed

Jiménez, B; Maya, C; Velásquez, G; Torner, F; Arambula, F; Barrios, J A; Velasco, M

2016-07-01

A system was developed to identify and quantify up to seven species of helminth eggs (Ascaris lumbricoides -fertile and unfertile eggs-, Trichuris trichiura, Toxocara canis, Taenia saginata, Hymenolepis nana, Hymenolepis diminuta, and Schistosoma mansoni) in wastewater using different image processing tools and pattern recognition algorithms. The system was developed in three stages. Version one was used to explore the viability of the concept of identifying helminth eggs through an image processing system, while versions 2 and 3 were used to improve its efficiency. The system development was based on the analysis of different properties of helminth eggs in order to discriminate them from other objects in samples processed using the conventional United States Environmental Protection Agency (US EPA) technique to quantify helminth eggs. The system was tested, in its three stages, considering two parameters: specificity (capacity to discriminate between species of helminth eggs and other objects) and sensitivity (capacity to correctly classify and identify the different species of helminth eggs). The final version showed a specificity of 99% while the sensitivity varied between 80 and 90%, depending on the total suspended solids content of the wastewater samples. To achieve such values in samples with total suspended solids (TSS) above 150 mg/L, it is recommended to dilute the concentrated sediment just before taking the images under the microscope. The system allows the helminth eggs most commonly found in wastewater to be reliably and uniformly detected and quantified. In addition, it provides the total number of eggs as well as the individual number by species, and for Ascaris lumbricoides it differentiates whether or not the egg is fertile. The system only requires basically trained technicians to prepare the samples, as for visual identification there is no need for highly trained personnel. The time required to analyze each image is less than a minute. This system could be used in central analytical laboratories providing a remote analysis service. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

In vitro and in vivo effects of ulipristal acetate on fertilization and early embryo development in mice.

PubMed

Gómez-Elías, Matías D; Munuce, María J; Bahamondes, Luis; Cuasnicú, Patricia S; Cohen, Débora J

2016-01-01

Does ulipristal acetate (UPA), a selective progesterone receptor modulator used for emergency contraception (EC), interfere with fertilization or early embryo development in vitro and in vivo? At doses similar to those used for EC, UPA does not affect mouse gamete transport, fertilization or embryo development. UPA acts as an emergency contraceptive mainly by inhibiting or delaying ovulation. However, there is little information regarding its effects on post-ovulatory events preceding implantation. This was an in vitro and in vivo experimental study involving the use of mouse gametes and embryos from at least three animals in each set of experiments. For in vitro fertilization experiments, mouse epididymal spermatozoa capacitated in the presence of different concentrations of UPA (0-1000 ng/ml) were used to inseminate cumulus-intact or cumulus-free eggs in the presence or absence of UPA during gamete co-incubation, and the percentage of fertilized eggs was determined. For in vivo fertilization experiments, superovulated females caged with proven fertile males were injected with UPA (40 mg/kg) or vehicle just before or just after mating and the percentage of fertilized eggs recovered from the ampulla was determined. To investigate the effect of UPA on embryo development, zygotes were recovered from mated females, cultured in the presence of UPA (1000 ng/ml) for 4 days and the progression of embryo development was monitored daily. In vitro studies revealed that the presence of UPA during capacitation and/or gamete co-incubation does not affect fertilization. Whereas the in vivo administration of UPA at the same time as hCG injection produced a decrease in the number of eggs ovulated compared with controls (vehicle injected animals, P < 0.05), no effects on fertilization were observed when UPA was administered shortly before or after mating. No differences were observed in either the percentage of cleaved embryos or the cleavage speed when UPA was present during in vitro embryo culture. Considering the ethical and technical limitations inherent to the use of human gametes for fertilization studies, the mouse model was used as an approach for exploring the potential effects of UPA on in vivo sperm transport and fertilization. Nevertheless, the extrapolation of these results to humans requires further investigation. This study presents new evidence on the lack of effect of UPA on gamete interaction and embryo development, providing new insights into the mechanism of action of UPA as an emergency contraceptive method with potential clinical implications. These new findings could contribute to increase the acceptability and proper use of UPA as an emergency contraceptive method. This study was partially supported by a National Agency of Scientific and Technological Promotion (ANPCyT), Argentina grants PICT 2011-061 to D.J.C. and PICT 2011-2023 to P.S.C. None of the authors has any competing interests to declare. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Parthenogenesis in unfertilized eggs of Coturnix chinensis, the Chinese painted quail, and the effect of egg clutch position on embryonic development.

PubMed

Parker, H M; McDaniel, C D

2009-04-01

Parthenogenesis, embryonic development of an unfertilized egg, was studied for many years in turkeys. In fact, as many as 49% of unfertilized Beltsville Small White turkey eggs develop embryos. However, no research exists on parthenogenesis in quail. The Chinese painted quail is a close relative of the more common Japanese quail and, unlike turkeys or chickens, the small Chinese painted quail reaches sexual maturity rapidly, making it a great candidate for further research on parthenogenesis. Obviously, a better understanding of avian parthenogenesis should increase our knowledge of avian fertilization and early embryonic development. Therefore, we determined if unfertilized Chinese painted quail hens produce embryos. Second, we explored the possibility that position of the egg within the clutch influences parthenogenesis. When initial secondary sexual plumage was apparent at 4 wk of age, male chicks were separated from females to prevent fertilization. Hens were placed in individual cages near sexual maturity, at approximately 6 wk of age. Individual eggs were collected daily and labeled with hen number and date. Eggs were stored for 0 to 3 d at 20 degrees C before incubation at 37.5 degrees C. After 10 d of incubation, approximately 4,000 eggs from 300 laying hens were examined for embryonic development under a magnifying lamp. On average, 4.8% of the unfertilized eggs contained an abortive form of embryonic development consisting of undifferentiated cells and unorganized membranes. Approximately 27% of the laying hens produced at least 1 egg with parthenogenic development. However, about 10% (30) of these hens exhibited a predisposition for parthenogenesis by producing 2 or more unfertilized eggs with embryonic development. Twenty percent of the eggs from 2 hens produced embryonic development. Additionally, the first egg laid in a clutch was most likely to produce embryonic development, with a steady decline in the percentage of eggs with embryonic development as position in the clutch increased. In conclusion, the Chinese painted quail does exhibit parthenogenesis and clutch position influences the rate of naturally occurring parthenogenesis.

Fatal ovarian hyperstimulation syndrome in an anonymous egg donor.

PubMed

Pooniya, Shashank; Behera, C; Mridha, A R; Bhardwaj, D N; Millo, Tabin

2016-12-01

Ovarian hyperstimulation syndrome is a rare, but potentially life-threatening iatrogenic disorder arising from ovulation induction or ovarian hyperstimulation for assisted reproduction techniques. We report a case of a 26-year-old multiparous woman, an anonymous egg donor, who died a few hours after undergoing a procedure to donate eggs at an in vitro fertilization clinic. Her husband alleged that medical negligence had led to her death. The autopsy confirmed death due to ovarian hyperstimulation syndrome. We know of no previous descriptions of fatal ovarian hyperstimulation syndrome in an anonymous egg donor in medico-legal literature. © The Author(s) 2016.

Effect of Dietary L-ascorbic Acid (L-AA) on Production Performance, Egg Quality Traits and Fertility in Japanese Quail (Coturnix japonica) at Low Ambient Temperature.

PubMed

Shit, N; Singh, R P; Sastry, K V H; Agarwal, R; Singh, R; Pandey, N K; Mohan, J

2012-07-01

Environmental stress boosts the levels of stress hormones and accelerates energy expenditure which subsequently imbalance the body's homeostasis. L-ascorbic acid (L-AA) has been recognized to mitigate the negative impact of environmental stress on production performances in birds. The present investigation was carried out to elucidate the effect of different dietary levels of L-AA on production performance, egg quality traits and fertility in Japanese quail at low ambient temperature. Sixty matured females (15 wks) were equally divided into three groups (20/group) based on the different dietary levels of L-AA (0, 250 and 500 ppm) and coupled with an equal number of males (1:1) obtained from the same hatch. They were managed in uniform husbandry conditions without restriction of feed and water at 14 h photo-schedule. Except for feed efficiency, body weight change, feed consumption and hen-day egg production were recorded highest in 500 ppm L-AA supplemented groups. Among the all egg quality traits studied, only specific gravity, shell weight and thickness differed significantly (p<0.05) in the present study. Fertility was improved significantly (p<0.01) to a dose dependent manner of L-AA. The findings of the present study concluded that dietary L-AA can be a caring management practice at least in part to alleviate the adverse effect of cold induced stress on production performance in Japanese quail.

Detection of Echinococcus granulosus and Echinococcus ortleppi in Bhutan.

PubMed

Thapa, Nirmal Kumar; Armua-Fernandez, Maria Teresa; Kinzang, Dukpa; Gurung, Ratna B; Wangdi, Phuntsho; Deplazes, Peter

2017-04-01

In this pilot study, fecal samples were collected from community dogs around slaughterhouses and from the city of Thimphu (n=138) as well as from carnivores in the forest area around a farm in Bhutan (n=28). Samples were analyzed microscopically for the presence of taeniid eggs by the floatation and sieving method. Further molecular analyses of 20 samples of community dogs positive for taeniid eggs confirmed 10 Echinococcus granulosus sensu lato and one Taenia hydatigena case. From 14 environmental fecal samples from the forest area positive for taeniid eggs, one contained E. granulosus s.l., six T. hydatigena and one Taenia taeniaeformis DNA. In the remaining samples considered positive for taeniid eggs, no molecular confirmation could be achieved. Additionally, Echinococcus cysts were collected from locally slaughtered cattle and imported cattle organs. Seven Echinococcus cysts (one fertile) from the local animals and 35 (four fertile) from imported cattle organs were confirmed as E. granulosus (G1-3) by PCR/sequencing. One Echinococcus cyst each from a local animal and from an imported cattle organ (both fertile) were confirmed to be Echinococcus ortleppi (G5). Sterile Echinococcus cysts were also collected from local yaks (n=10), and all revealed to be E. granulosus (G1-G3). Hospital records of cystic echinococcosis in humans and the presence of Echinococcus spp. in dogs and ungulates indicate the existence of local transmission for both E. ortleppi and E. granulosus in Bhutan. Copyright © 2016. Published by Elsevier B.V.

Collection of gametes from live axolotl, Ambystoma mexicanum, and standardization of in vitro fertilization.

PubMed

Mansour, N; Lahnsteiner, F; Patzner, R A

2011-01-15

This study established the first protocol for collection of gametes from live axolotl, Ambystoma mexicanum, by gentle abdominal massage and in vitro fertilization. To stimulate spermiation and ovulation, human chorionic gonadotrophin (hCG) and Ovopel pellets, which are commercially used to stimulate spawning in fish, were tested. The hCG was more effective than Ovopel pellets and yielded a higher semen volume in the injected males and a shorter response time in the females. Collected semen by this method was already motile and fertile. Fertile eggs could be collected in 3-4 successive collection times after the female has started the typical spawning behaviour. The fertilization condition that yielded the highest hatching rate was mixing semen with eggs before the addition of a fertilization saline solution (20 mmol/l NaCl, 1 mmol/l KCl, 1 mmol/l Mg(2)SO(4), 1 mmol Ca(2)Cl, 3 mmol NaHCO(3), 10 mmol/l Tris, pH 8.5 - Osmolality = 65 mosmol/kg). When the pH of the fertilization solution was increased to ≥ 10, the hatching rate was significantly increased. The use of fertilization solutions with osmolalities of ≥ 150 and ≥ 182 were accompanied with a significant decrease in hatching rates and the appearance of deformed larvae, respectively. In conclusion, a reliable protocol for gamete collection from live axolotl is established as a laboratory model of in vitro fertilization for urodele amphibians. This protocol may be transferable to endangered urodeles. Copyright © 2011 Elsevier Inc. All rights reserved.

Oviposition strategies of conifer seed chalcids in relation to host phenology.

PubMed

Rouault, Gaëlle; Turgeon, Jean; Candau, Jean-Noël; Roques, Alain; von Aderkas, Patrick

2004-10-01

Insects are considered the most important predators of seed cones, the female reproductive structures of conifers, prior to seed dispersal. Slightly more than 100 genera of insects are known to parasitize conifer seed cones. The most diverse (i.e., number of species) of these genera is Megastigmus (Hymenoptera: Torymidae), which comprises many important seed pests of native and exotic conifers. Seed chalcids, Megastigmus spp., lay eggs inside the developing ovules of host conifers and, until recently, oviposition was believed to occur only in fertilized ovules. Ovule development begins just after pollination, but stops if cells are not fertilized. The morphological stage of cone development at the time of oviposition by seed chalcids has been established for many species; however, knowledge of ovule development at that time has been documented for only one species, M. spermotrophus. Megastigmus spermotrophus oviposits in Douglas-fir ovules after pollination but before fertilization. Unlike the unfertilized ovules, those containing a M. spermotrophus larva continue to develop, whether fertilized or not, stressing the need to broaden our understanding of the insect-plant interactions for this entire genus. To achieve this task, we reviewed the scientific literature and assembled information pertaining to the timing of oviposition and to the pollination and fertilization periods of their respective host(s). More specifically, we were searching for circumstantial evidence that other species of Megastigmus associated with conifers could behave (i.e., oviposit before ovule fertilization) and impact on female gametophyte (i.e., prevent abortion) like M. spermotrophus. The evidence from our compilation suggests that seed chalcids infesting Pinaceae may also oviposit before ovule fertilization, just like M. spermotrophus, whereas those infesting Cupressaceae seemingly oviposit after ovule fertilization. Based on this evidence, we hypothesize that all species of Megastigmus associated with Pinaceae can oviposit in unfertilized ovules, whereas those exploiting Cupressaceae cannot, and thus oviposit only in already fully developed fertilized seeds. Furthermore, we predict that the presence of a larva in unfertilized ovules of all Pinaceae will influence the development of the female gametophyte by preventing its abortion. This influence on the Pinaceae can be interpreted as an ability to parasitize any of the potential seeds present in a seed cone, and as such represents a much more efficient oviposition strategy than searching and locating only fertilized seeds. Concomitantly, this ability has likely led to an overestimation of the impact of the species of seed chalcid infesting Pinaceae on seed production.

Oviposition strategies of conifer seed chalcids in relation to host phenology

NASA Astrophysics Data System (ADS)

Rouault, Gaëlle; Turgeon, Jean; Candau, Jean-Noël; Roques, Alain; Aderkas, Patrick

2004-10-01

Insects are considered the most important predators of seed cones, the female reproductive structures of conifers, prior to seed dispersal. Slightly more than 100 genera of insects are known to parasitize conifer seed cones. The most diverse (i.e., number of species) of these genera is Megastigmus (Hymenoptera: Torymidae), which comprises many important seed pests of native and exotic conifers. Seed chalcids, Megastigmus spp., lay eggs inside the developing ovules of host conifers and, until recently, oviposition was believed to occur only in fertilized ovules. Ovule development begins just after pollination, but stops if cells are not fertilized. The morphological stage of cone development at the time of oviposition by seed chalcids has been established for many species; however, knowledge of ovule development at that time has been documented for only one species, M. spermotrophus. Megastigmus spermotrophus oviposits in Douglas-fir ovules after pollination but before fertilization. Unlike the unfertilized ovules, those containing a M. spermotrophus larva continue to develop, whether fertilized or not, stressing the need to broaden our understanding of the insect plant interactions for this entire genus. To achieve this task, we reviewed the scientific literature and assembled information pertaining to the timing of oviposition and to the pollination and fertilization periods of their respective host(s). More specifically, we were searching for circumstantial evidence that other species of Megastigmus associated with conifers could behave (i.e., oviposit before ovule fertilization) and impact on female gametophyte (i.e., prevent abortion) like M. spermotrophus. The evidence from our compilation suggests that seed chalcids infesting Pinaceae may also oviposit before ovule fertilization, just like M. spermotrophus, whereas those infesting Cupressaceae seemingly oviposit after ovule fertilization. Based on this evidence, we hypothesize that all species of Megastigmus associated with Pinaceae can oviposit in unfertilized ovules, whereas those exploiting Cupressaceae cannot, and thus oviposit only in already fully developed fertilized seeds. Furthermore, we predict that the presence of a larva in unfertilized ovules of all Pinaceae will influence the development of the female gametophyte by preventing its abortion. This influence on the Pinaceae can be interpreted as an ability to parasitize any of the potential seeds present in a seed cone, and as such represents a much more efficient oviposition strategy than searching and locating only fertilized seeds. Concomitantly, this ability has likely led to an overestimation of the impact of the species of seed chalcid infesting Pinaceae on seed production.

Occurrence of Partial Nuclei in Eggs of the Sand Dollar, Clypeaster japonicus.

PubMed

Yoneda, M; Nemoto, S I

1990-10-01

Females of Clypeaster japonicus bearing eggs with multiple nuclei were occasionally found. DAPI (4'-6-diamidino-2-phenylindole) stained all these nuclei. The summed volume of the two nuclei in binucleate eggs was similar to the nuclear volume in mononucleate eggs from the same batch. On fertilization, two partial nuclei migrated to the center of the egg with a time-course similar to that taken by a single nucleus; they then participated in forming the zygote nucleus, which subsequently formed a single mitotic spindle. These multiple nuclei thus appear to function as genuine nuclei. Possibly they result from the failure of a single nucleus to form during oogenesis.

Effects of immobilization by electricity and MS-222 on brown trout broodstock and their progeny

USGS Publications Warehouse

Redman, S.D.; Meinertz, J.R.; Gaikowski, M.P.

1998-01-01

To determine the effects of electrically and chemically induced immobilization on postspawn broodstock and their progeny, age-2 and age-3 female broodstock and age-2 male broodstock of brown trout Salmo trutta were immobilized with electricity or tricaine methanesulfonate (MS-222), stripped of their eggs or milt, and weighed. Eggs taken from electrically immobilized females were fertilized with milt taken from age-2 males that were immobilized with electricity, and eggs taken from females immobilized with MS-222 were fertilized with milt taken from age-2 males that were immobilized with MS-222. After spawning, the mortality and weight of broodstock were compared twice over a 6-month period. Egg viability and growth of offspring fry from each treatment group were also compared. Electricity induced complete and consistent immobilization in brown trout broodstock. Electrically immobilized fish were more easily handled than fish immobilized with MS-222; however, electrically immobilized fish survival (70%) was significantly less than fish immobilized with MS-222 (83%). Broodstock growth differences were only noted at 6 months postexposure, when the mean weight of electrically immobilized fish was slightly less than the weight of fish immobilized with MS-222. Broodstock immobilization by electricity did not reduce egg viability or fry growth.

Eggs: The role of gravity in the establishment of the dorso-ventral axis in the amphibian embryo (7-IML-1)

NASA Technical Reports Server (NTRS)

Ubbels, Geertje A.

1992-01-01

The purpose of this experiment is to fertilize frog (Xenopus laevis) eggs under microgravity, to perform histological fixations at two different programmed times, and after return to Earth, to determine whether timing and pattern of egg cleavages and axis formation are normal. Because of the limited viability of the gametes, this experiment will be the very first to be activated in the Biorack. Various aspects of this investigation are discussed.

Patent gastrointestinal nematode infections in organically and conventionally pastured dairy cows and their impact on individual milk and fertility parameters.

PubMed

May, Katharina; Brügemann, Kerstin; König, Sven; Strube, Christina

2017-10-15

Infections with gastrointestinal nematodes (GIN) can lead to production losses and impacts on product quality in affected cows, which has mainly been demonstrated during deworming experiments or via herd-level measurements. Here, a field study was carried out to explore the association between GIN infection status and milk production as well as fertility parameters in individual dairy cows. Different selection lines of Black and White cows were included in the study, which were distributed among 17 small and medium-sized organic and conventional German grassland farms. Faecal samples of 1166 dairy cows were examined twice, in July and September 2015. Nematode eggs were found in the faeces of 473 (40.6%) cows. As expected, strongylid eggs (Trichostrongylidae or Oesophagostomum and Bunostomum spp., respectively) were the predominant morphotype, followed by Strongyloides papillosus and Capillaria spp. eggs. In July, cows kept under organic conditions had a significantly lower GIN prevalence in comparison to cows kept on conventional farms. Faecal egg counts were generally low, with the highest value in September and an arithmetic mean of 11.3 eggs per gram faeces (EPG) for all observations. The relationships between GIN infection status and milk yield (kg milk/cow/day), milk protein content (%) and milk fat content (%) for each first test-day record after parasitological assessment were estimated by using linear mixed models. Milk protein content was estimated 0.05% lower in GIN positive compared to GIN negative cows, whereas no significant effect on milk yield or milk fat content was observed. The impact of GIN infection status on success in first insemination (SFI) was estimated by using a threshold model. No significant association was demonstrated between GIN infection status and SFI. Unexpectedly, the fertility parameter days from calving-to-first-service (CTFS) showed a significantly shorter average interval in GIN positive cows. However, these data on reproductive performance need to be considered preliminary as long-term studies are needed to allow a firm prediction of the impact of GIN infection status on dairy cow fertility parameters. Copyright © 2017 Elsevier B.V. All rights reserved.

9 CFR 93.904 - Health certificate for live fish, fertilized eggs, and gametes.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Health certificate for live fish... ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN ANIMAL, BIRD, AND... General Provisions for Svc-Regulated Fish Species § 93.904 Health certificate for live fish, fertilized...

Cytoplasmic rearrangements associated with amphibian egg symmetrization

NASA Technical Reports Server (NTRS)

Malacinski, G. M.

1984-01-01

Cytoplasmic rearrangements which follow fertilization were mentioned in normal and inverted eggs. A set of yolk compartments was resolved by cytological analyses of both normally oriented and inverted eggs. Those compartments were characterized by their yolk platelet compositions and movement during egg inversion. It is found that during egg inversion the yolk compartments shift minor cytoplasmic compartments which line the egg cortex. Those yolk mass shifts occurred only after the inverted egg was activated. The direction of shift of the major yolk components, rather than the sperm entrance site, determines the dorsal/ventral polarity of the inverted egg. Among different spawnings the rate of shift varied. Eggs that displayed the fastest rate of shift exhibited the highest frequency of developmental abnormalities during organogenesis. Interpretation of novel observations on cytoplasmic organization provide criticism of some earlier models. A new density compartment model is presented as a coherent way to view the organization of the egg cytoplasm and the development of bilateral symmetry.

Quality of Pinzgau bull spermatozoa following different periods of cryostorage.

PubMed

Chrenek, P; Spaleková, E; Olexikova, L; Makarevich, A; Kubovicova, E

2017-04-01

The aim of this work was to examine the influence of cryostorage duration of Pinzgau bull's insemination doses (IDs) on some sperm traits. The IDs were frozen by a slow freezing method and stored in liquid nitrogen for different periods: less than 8 years (group 1), 8-13 years (group 2) and 14-18 years (group 3). Motility (CASA), pathological sperm rate (Giemsa staining), apoptotic (Yo-Pro-1-positive) and necrotic (propidium iodide-positive) cell occurrence and fertilizing ability (penetration/fertilization test) of spermatozoa were evaluated post-thaw. The average post-thaw sperm motility in all examined groups was over 40%. No significant influence of storage length either on the sperm total motility or progressive movement was revealed. In each tested group the average rate of malformed spermatozoa did not exceed 20%. No effect of cryostorage length on the occurrence of apoptotic or necrotic sperm was noted. Similarly, penetrating/fertilizing ability of sperm did not differ among the groups, excepting differences in the rate of pronuclei (PN) formation. In group 1, 72.9% of eggs showed two visible PN following 20 h incubation with sperm, whilst in groups 2 and 3 only 67 and 54.5% of zygotes, respectively, had both PN at this time. These results revealed no influence of storage time on the bull spermatozoa in all parameters excepting the rate of PN formation. As high inter-male variability was observed in the susceptibility of bull sperm to cryostorage, individual differences should be taken into account when semen from individual bulls is to be stored for a long time.

Management of Sexual Maturation and Natural Spawning of Captive- Reared Yellowtail Kingfish, Seriola lalandi, in an Indoor Rearing Tank.

PubMed

Yang, Sang Geun; Ji, Seung Cheol; Lim, Sang Gu; Hur, Sang Woo; Jeong, Minhwan; Lee, Chi Hoon; Kim, Bong Seok; Lee, Young-Don

2016-06-01

This study describes results on sexual maturation and characteristics of natural spawned eggs to develop a method for the production of stable, healthy fertilized eggs from captive-reared yellowtail kingfish, Seriola lalandi. A total of 59 yellowtail kingfish were captured off the coast of Jeju Island, after which the broodstock was cultured in indoor culture tank (100 m(3)) until they were 6.1-14.9 kg in body weight. As part of the rearing management for induced sex maturation, the intensity of illumination was maintained at 130 lux. The photoperiod (light/dark; L/D) was set to a 12 L/12 D from October 2013 to January 2014, and 15 L/9 D from February 2014 to June 2014. Feeds comprised mainly EP (Extruded Pellets), with squid cuttlefish added for improvement of egg quality, and was given from April to June 2014. The first spawning of yellowtail kingfish occurred in May 3, 2014, at a water temperature of 17.0°C. Spawning continued until June 12, 2014, with the water temperature set at 20.5°C. Time of spawning was 26 times at this period. The total number of eggs that spawned during the spawning period was 4,449×10(3). The buoyant rate of spawning eggs and fertilization rate of buoyant eggs during the spawned period were 76.1% and 100%, respectively. The diameters of the egg and oil globule were 1.388 ± 0.041 mm and 0.378 ± 0.029 mm, respectively, which was higher in early eggs than in those from late during the spawned period.

Rainbow trout embryotoxicity of a complex contaminant mixture extracted from Lake Michigan lake trout

USGS Publications Warehouse

Wilson, P.J.; Tillitt, D.E.

1996-01-01

Persistent Hydrophobic contaminants such as poly chlorinated dibenzo-p-dioxins, dibenzofurans and biphenyl congeners are present in aquatic systems, and are known to produce adverse effects in fish. Reproductive failure in fish populations has been observed in aquatic systems contaminated with persistent hydrophobic compounds. In order to mimic maternal transfer of environmental contaminants to newly fertilized fish eggs, a complex environmental extract was tested for embryotoxicity in a nanoinjection bioassay with embryos of rainbow trout. The extract was obtained from whole adult lake trout collected from Lake Michigan in 1988. The tissue extraction involved blending and dehydration with sodium sulfate, column extraction, dialysis separation, reactive cleanup and, finally, high-performance gel permeation chromatography. Egg gram-equivalent doses (g tissue/g egg normalized for egg % lipid) of the final extract (0.02, 0.10, 0.20, 1.0, 2.0, 4.0, 10.0, 20.0 eggEQ) were injected into newly fertilized rainbow trout eggs using triolein as the vehicle. The extract of the lake trout was embryotoxic to rainbow trout, with an LD50 of 35 eggEQ, based on total cumulative mortality. Gross physical abnormalities characteristic of dioxin exposure, such as hemorrhaging, yolk-sac edema and craniofacial deformities, were observed and showed significant dose-related increases. Sublethal effects in the rainbow trout, such as delayed time to hatch, mild hemorrhaging and moderate yolk-sac edema, resulted from estimated total PCB exposure as low as 8.8 ng/g, and this may have significant implications on Great Lakes lake trout fry and juvenile mortality.

Gonad morphology, gametogenesis, and reproductive modes in fishes of the tribe Starksiini (Teleostei, Blenniiformes).

PubMed

Fishelson, Lev; Baldwin, Carole C; Hastings, Philip A

2013-05-01

A comparative study of the reproductive organs in 17 of the 30 species of the tribe Starksiini (Labrisomidae, Blenniiformes) and related labrisomids reveals the major traits of gamete form and production and likely reproductive modes. The testes are of the lobular type and have a testicular gland and sperm ducts. Isodiametric sperm (aquasperm) with a globular head or anisodiametric sperm (introsperm) with an elongate head, or both, were observed in the studied species. Both types have either one or two flagella in the sperm tail. Ovaries of the Starksiini are bilobed and exhibit synchronous or asynchronous egg production. Although viviparity or "ovoviviparity" reportedly characterizes the group, our study revealed evidence of both internal and external fertilization and three modes of reproduction. External fertilization or ovuliparity is suggested for the Starksia atlantica and S. lepicoelia species complexes by the presence in males of a short genital papilla that is not reinforced through adhesion with the first anal-fin spine and by the absence of sperm within the ovaries. Internal fertilization and zygoparity is indicated for most species by the presence of an intromittent papilla in males that is adhered to the first anal-fin spine, "nests" of sperm within the ovaries, absence of embryos within the ovarian lamellae and usually thick egg envelopes bearing dense covers of adhesive filaments. Internal fertilization and embryoparity is indicated for starksia fulva and Xenomedea rhodopyga by an intromittent papilla that is adhered to the first anal-fin spine of males, anisodiametric sperm in males, delicate egg envelopes without adhesive filaments and developing embryos within follicular envelopes or within the follicle in females. Although many of these features are seen in the internally fertilizing clinid blennies, starksiins differ in retaining the testicular gland typical of labrisomids and in lacking sperm packaging typical of other internally fertilizing teleosts. Copyright © 2013 Wiley Periodicals, Inc.

IVF versus ICSI for the fertilization of in-vitro matured human oocytes.

PubMed

Walls, M; Junk, S; Ryan, J P; Hart, R

2012-12-01

Traditional dogma suggests that intracytoplasmic sperm injection (ICSI) should be performed to ensure successful oocyte fertilization in an in-vitro maturation (IVM) cycle. This study postulated that there would be no difference in the fertilization rate when ICSI was compared with IVF. This hypothesis was tested in a randomized trial of IVF versus ICSI in IVM. A total of 150 immature oocytes were collected in eight cycles of IVM for patients diagnosed with polycystic ovarian syndrome (PCOS). Patients were primed with minimal FSH before transvaginal oocyte aspiration. Sibling oocytes were inseminated by 50% IVF and 50% ICSI. There was no significant difference in fertilization, useable or total blastocyst development between the two insemination technique groups. Clinical pregnancy results for combined fresh and cryopreserved transfers were identical between the two insemination techniques with a total of two fresh and five cryopreserved IVF-inseminated embryos resulting in three clinical pregnancies (42.9%) and five fresh and two cryopreserved ICSI-derived embryos resulting in three clinical pregnancies (42.9%). This research has shown IVF to be a legitimate fertilization technique for IVM oocytes in PCOS patients and provides a greater awareness of the use of a fertilization method previously not utilized with IVM. In-vitro maturation (IVM) is an alternative treatment method to traditional IVF. Due to the minimal use of stimulating hormones in this treatment, IVM has a lower risk of ovarian hyperstimulation syndrome, it can be used for fertility preservation in cancer patients and it is more cost conservative. Early research into the effects of IVM showed a hardening effect on the membrane surrounding the egg (the zona pellucida). It was initially believed that, to overcome this hardening in order to allow the egg to be fertilized, spermatozoa would need to be injected into the egg using intracytoplasmic sperm injection. Due to recent advances in hormonal stimulation protocols (FSH priming) and culture conditions, we postulated that, for patients suffering from polycystic ovarian syndrome (PCOS), fertilization, embryo development and clinical pregnancy would not be superior in the injected oocytes compared with those inseminated by IVF. We found that by using the two insemination techniques on sibling oocytes from eight PCOS patients, there was no significant difference in fertilization, useable or total blastocyst development (day 5 or 6 embryos) and that clinical pregnancy results were identical. This research provides a greater awareness of a fertilization technique which is not normally utilized for IVM treatment, providing a less invasive, more cost-effective approach for the patient. Copyright © 2012 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Post-copulatory opportunities for sperm competition and cryptic female choice provide no offspring fitness benefits in externally fertilizing salmon

PubMed Central

Lumley, Alyson J.; Diamond, Sian E.; Einum, Sigurd; Yeates, Sarah E.; Peruffo, Danielle; Emerson, Brent C.; Gage, Matthew J. G.

2016-01-01

There is increasing evidence that females can somehow improve their offspring fitness by mating with multiple males, but we understand little about the exact stage(s) at which such benefits are gained. Here, we measure whether offspring fitness is influenced by mechanisms operating solely between sperm and egg. Using externally fertilizing and polyandrous Atlantic salmon (Salmo salar), we employed split-clutch and split-ejaculate in vitro fertilization experiments to generate offspring using designs that either denied or applied opportunities for sperm competition and cryptic female choice. Following fertilizations, we measured 140 days of offspring fitness after hatch, through growth and survival in hatchery and near-natural conditions. Despite an average composite mortality of 61%, offspring fitness at every life stage was near-identical between groups fertilized under the absence versus presence of opportunities for sperm competition and cryptic female choice. Of the 21 551 and 21 771 eggs from 24 females fertilized under monandrous versus polyandrous conditions, 68% versus 67.8% survived to the 100-day juvenile stage; sub-samples showed similar hatching success (73.1% versus 74.3%), had similar survival over 40 days in near-natural streams (57.3% versus 56.2%) and grew at similar rates throughout. We therefore found no evidence that gamete-specific interactions allow offspring fitness benefits when polyandrous fertilization conditions provide opportunities for sperm competition and cryptic female choice. PMID:27069665

Comparative detection of calcium fluctuations in single female sex cells of tobacco to distinguish calcium signals triggered by in vitro fertilization.

PubMed

Peng, Xiong-Bo; Sun, Meng-Xiang; Yang, Hong-Yuan

2009-08-01

Double fertilization is a key process of sexual reproduction in higher plants. The role of calcium in the activation of female sex cells through fertilization has recently received a great deal of attention. The establishment of a Ca(2+)-imaging technique for living, single, female sex cells is a difficult but necessary prerequisite for evaluating the role of Ca(2+) in the transduction of external stimuli, including the fusion with the sperm cell, to internal cellular processes. The present study describes the use of Fluo-3 for reporting the Ca(2+) signal in isolated, single, female sex cells, egg cells and central cells, of tobacco plants. A suitable loading protocol was optimized by loading the cells at pH 5.6 with 2 microM Fluo-3 for 30 min at 30 degrees C. Under these conditions, several key factors related to in vitro fertilization were also investigated in order to test their possible effects on the [Ca(2+)](cyt) of the female sex cells. The results indicated that the bovine serum albumin-fusion system was superior to the polyethlene glycol-fusion system for detecting calcium fluctuations in female sex cells during fertilization. The central cell was fertilized with the sperm cell in bovine serum albumin; however, no evident calcium dynamic was detected, implying that a transient calcium rise might be a specific signal for egg cell fertilization.

Male Investments in High Quality Sperm Improve Fertilization Success, but May Have Negative Impact on Offspring Fitness in Whitefish

PubMed Central

Kekäläinen, Jukka; Soler, Carles; Veentaus, Sami; Huuskonen, Hannu

2015-01-01

Many ejaculate traits show remarkable variation in relation to male social status. Males in disfavoured (subordinate) mating positions often invest heavily on sperm motility but may have less available resources on traits (e.g., secondary sexual ornaments) that improve the probability of gaining matings. Although higher investments in sperm motility can increase the relative fertilization success of subordinate males, it is unclear whether status-dependent differences in sperm traits could have any consequences for offspring fitness. We tested this possibility in whitefish (Coregonus lavaretus L.) by experimentally fertilizing the eggs of 24 females with the sperm of either highly-ornamented (large breeding tubercles, dominant) or less-ornamented (small tubercles, subordinate) males (split-clutch breeding design). In comparison to highly-ornamented individuals, less-ornamented males had higher sperm motility, which fertilized the eggs more efficiently, but produced embryos with impaired hatching success. Also offspring size and body condition were lower among less-ornamented males. Furthermore, sperm motility was positively associated with the fertilization success and offspring size, but only in highly-ornamented males. Together our results indicate that male investments on highly motile (fertile) sperm is not necessarily advantageous during later offspring ontogeny and that male status-dependent differences in sperm phenotype may have important effects on offspring fitness in different life-history stages. PMID:26389594

The intimate genetics of Drosophila fertilization

PubMed Central

Loppin, Benjamin; Dubruille, Raphaëlle; Horard, Béatrice

2015-01-01

The union of haploid gametes at fertilization initiates the formation of the diploid zygote in sexually reproducing animals. This founding event of embryogenesis includes several fascinating cellular and nuclear processes, such as sperm–egg cellular interactions, sperm chromatin remodelling, centrosome formation or pronuclear migration. In comparison with other aspects of development, the exploration of animal fertilization at the functional level has remained so far relatively limited, even in classical model organisms. Here, we have reviewed our current knowledge of fertilization in Drosophila melanogaster, with a special emphasis on the genes involved in the complex transformation of the fertilizing sperm nucleus into a replicated set of paternal chromosomes. PMID:26246493

$sup 35$S Metabolism in the Physiology of Mammals Reproduction; METABOLISME DU 35S DANS LA PHYSIOLOGIE DE LA REPRODUCTION CHEZ LES MAMMIFERES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moricard, R.; Gothie, S.; Rodriguez-Galindo, M.

1959-10-31

From ovulation to nidation in the uterus, the spermatozoa, the second order ovocyte, and the fertilized egg are free in the genital secretions whose sulfur amount depends on ovarian hormones. The spermatozoa can fix S/sup 35/ in vitro and they seem to be able to metabolize this element during their ascent through the genital tract. In the uterus and in the mucosa of the cervix, there is an intense and fast metabolism of the S/sup 35/ in the guinea pig. In the fallopian tube, fecondation takes place in the secretions in which S/sup 35/ metabolism is at the highest degreemore » at fertilization. As soon as the second polar body is expelled, the pellucida has a very high concentration of S/sup 35/, whether the latter is injected in the form of Na/sub 2/S/sup 35/O/sub 4/ or cystine. This concentration is not only due to fertilization, it appears also in unfertilized eggs. In vitro cultures of ovarian ovocytes, tubal eggs, and uterine blastocytes show the protective part played by the pellucida and its concentrating power, a function which does not seem to be performed by the pellucida of first-order ovocytes. (auth)« less

How cuckoldry can decrease the opportunity for sexual selection: Data and theory from a genetic parentage analysis of the sand goby, Pomatoschistus minutus

PubMed Central

Jones, Adam G.; Walker, DeEtte; Kvarnemo, Charlotta; Lindström, Kai; Avise, John C.

2001-01-01

Alternative mating strategies are common in nature and are generally thought to increase the intensity of sexual selection. However, cuckoldry can theoretically decrease the opportunity for sexual selection, particularly in highly polygamous species. We address here the influence of sneaking (fertilization thievery) on the opportunity for sexual selection in the sand goby Pomatoschistus minutus, a marine fish species in which males build and defend nests. Our microsatellite-based analysis of the mating system in a natural sand goby population shows high rates of sneaking and multiple mating by males. Sneaker males had fertilized eggs in ≈50% of the assayed nests, and multiple sneakers sometimes fertilized eggs from a single female. Successful males had received eggs from 2 to 6 females per nest (mean = 3.4). We developed a simple mathematical model showing that sneaking in this polygynous sand goby population almost certainly decreases the opportunity for sexual selection, an outcome that contrasts with the usual effects of cuckoldry in socially monogamous animals. These results highlight a more complex and interesting relationship between cuckoldry rates and the intensity of sexual selection than previously assumed in much of the literature on animal mating systems. PMID:11481481

Egg incubation position affects toxicity of air cell administered PCB 126 (3,3?4,4?,5- pentachlorobiphenyl) in chicken (Gallus domesticus) embryos

USGS Publications Warehouse

McKernan, M.A.; Rattner, B.A.; Hale, R.C.; Ottinger, M.A.

2007-01-01

The avian egg is used extensively for chemical screening and determining the relative sensitivity of species to environmental contaminants (e.g., metals, pesticides, polyhalogenated compounds). The effect of egg incubation position on embryonic survival, pipping, and hatching success was examined following air cell administration of polychlorinated biphenyl (PCB) congener 126 (3,3',4,4',5-pentachlorobiphenyl [PCB 126]; 500?2,000 pg/g egg) on day 4 of development in fertile chicken (Gallus gallus) eggs. Depending on dose, toxicity was found to be up to nine times greater in vertically versus horizontally incubated eggs. This may be due to enhanced embryonic exposure to the injection bolus in vertically incubated eggs compared to more gradual uptake in horizontally incubated eggs. Following air cell administration of PCB 126, horizontal incubation of eggs may more closely approximate uptake and toxicity that has been observed with naturally incorporated contaminants. These data have implications for chemical screening and use of laboratory data for ecological risk assessments.

A simplified method for correcting contaminant concentrations in eggs for moisture loss.

USGS Publications Warehouse

Heinz, Gary H.; Stebbins, Katherine R.; Klimstra, Jon D.; Hoffman, David J.

2009-01-01

We developed a simplified and highly accurate method for correcting contaminant concentrations in eggs for the moisture that is lost from an egg during incubation. To make the correction, one injects water into the air cell of the egg until overflowing. The amount of water injected corrects almost perfectly for the amount of water lost during incubation or when an egg is left in the nest and dehydrates and deteriorates over time. To validate the new method we weighed freshly laid chicken (Gallus gallus) eggs and then incubated sets of fertile and dead eggs for either 12 or 19 d. We then injected water into the air cells of these eggs and verified that the weights after water injection were almost identical to the weights of the eggs when they were fresh. The advantages of the new method are its speed, accuracy, and simplicity: It does not require the calculation of a correction factor that has to be applied to each contaminant residue.

Comparative toxicity of two Iodophors to rainbow trout eggs

USGS Publications Warehouse

Amend, Donald F.

1974-01-01

Toxicity of Wescodyne(R) and Betadine(R) to eyed eggs was not adversely affected by water hardness (as calcium and magnesium) or by exposure periods up to 60 min. Both iodophors were much more toxic below pH 6.0 than at pH 8.0. In general Wescodyne was slightly more toxic than Betadine. Significant egg loss occurred if freshly fertilized eggs were water-hardened in either iodophor at 100 ppm of iodine, but egg loss at 25 ppm of iodine or at 100 ppm if the eggs were disinfected 30 min after water hardening was comparable to the control. Also, there was no effect on the egg mortality or fry development following single or multiple exposures after eggs were water hardened. At pH 6.0 and above, Wescodyne and Betadine at 100 ppm iodine in a 15-min dip would be safe to use on rainbow trout eggs at any stage of development after water hardening. Recommendations and precautions for hatchery use are given.

Kinematics of gray crescent formation in Xenopus eggs: the displacement of subcortical cytoplasm relative to the egg surface.

PubMed

Vincent, J P; Oster, G F; Gerhart, J C

1986-02-01

Specification of the amphibian dorso-ventral axis takes place in the period between fertilization and first cleavage when the gray crescent forms. In the course of gray crescent formation, the egg reorganizes its periphery by a movement for which two descriptions have been given. According to the "rotation hypothesis," which was originated and supported for Rana eggs, the entire egg cortex rotates by an arc of 30 degrees relative to the stationary subcortical cytoplasm, leaving the crescent as a zone of altered coloration. The "contraction hypothesis" on the other hand, which was proposed for Xenopus and Rana eggs, asserts that there is a cortical contraction focused at the sperm entry point that leads to stretching of the opposite equatorial zone at which the crescent appears. We have reinvestigated the case of Xenopus eggs by imprinting one kind of fluorescent dye pattern (Nile blue) onto the subcortical cytoplasm and another kind (fluorescein-lectin) onto the egg surface. When the egg surface is held fixed by embedding the egg in gelatin, two major movements of the subcortical cytoplasm are observable. First, starting at time 0.3 (30% of the time between fertilization and first cleavage), the animal hemisphere subcortical cytoplasm converges toward a point, while the vegetal hemisphere is quiescent. This convergence continues with decreasing strength until approximately 0.8 of the first cell cycle. Second, at 0.45, an overall rotation of the animal and vegetal subcortical cytoplasm commences, superimposed on the animal hemisphere convergence. By 0.8-0.9 the rotation is complete, having accomplished a 30 degrees displacement of the subcortical cytoplasm relative to the surface. This rotation reliably locates the future dorsal midline of the embryo at the meridian on which the displacement of the subcortical cytoplasm is greatest in a vegetal direction. In normal unembedded eggs, when the egg surface is free to move, it rotates 30 degrees relative to the subcortical cytoplasm, which remains stationary in a position of gravitational equilibrium. Although both a convergence and rotation occur in the Xenopus egg, we give evidence that the rotation, not the convergence (perhaps equated with contraction), specifies the embryo's prospective axis. Even though the Xenopus egg does not form a classical gray crescent, due to its particular pigment distribution, the reorganization process which specifies the future embryonic axis resembles that of the Rana egg.

White sturgeon spawning areas in the lower Snake River

USGS Publications Warehouse

Parsley, M.J.; Kappenman, K.M.

2000-01-01

We documented 17 white sturgeon Acipenser transmontanus spawning locations in the Snake River from the mouth to Lower Granite Dam (river km 0 to 173). Spawning locations were determined by the collection of fertilized eggs on artificial substrates or in plankton nets. We collected 245 eggs at seven locations in McNary Reservoir, 22 eggs at three locations in Ice Harbor Reservoir, 30 eggs from two locations in Lower Monumental Reservoir, and 464 eggs at five locations in Little Goose Reservoir. All 17 locations were in high water velocity areas and between 1.0 and 7.0 km downstream from a hydroelectric dam. The documentation of spawning areas is important because this habitat is necessary to maintain natural and viable populations.

Identification of metalloprotease/disintegrins in Xenopus laevis testis with a potential role in fertilization.

PubMed

Shilling, F M; Krätzschmar, J; Cai, H; Weskamp, G; Gayko, U; Leibow, J; Myles, D G; Nuccitelli, R; Blobel, C P

1997-06-15

Proteins containing a membrane-anchored metalloprotease domain, a disintegrin domain, and a cysteine-rich region (MDC proteins) are thought to play an important role in mammalian fertilization, as well as in somatic cell-cell interactions. We have identified PCR sequence tags encoding the disintegrin domain of five distinct MDC proteins from Xenopus laevis testis cDNA. Four of these sequence tags (xMDC9, xMDC11.1, xMDC11.2, and xMDC13) showed strong similarity to known mammalian MDC proteins, whereas the fifth (xMDC16) apparently represents a novel family member. Northern blot analysis revealed that the mRNA for xMDC16 was only expressed in testis, and not in heart, muscle, liver, ovaries, or eggs, whereas the mRNAs corresponding to the four other PCR products were expressed in testis and in some or all somatic tissues tested. The xMDC16 protein sequence, as predicted from the full-length cDNA, contains a metalloprotease domain with the active-site sequence HEXXH, a disintegrin domain, a cysteine-rich region, an EGF repeat, a transmembrane domain, and a short cytoplasmic tail. To study a potential role for these xMDC proteins in fertilization, peptides corresponding to the predicted integrin-binding domain of each protein were tested for their ability to inhibit X. laevis fertilization. Cyclic and linear xMDC16 peptides inhibited fertilization in a concentration-dependent manner, whereas xMDC16 peptides that were scrambled or had certain amino acid replacements in the predicted integrin-binding domain did not affect fertilization. Cyclic and linear xMDC9 peptides and linear xMDC13 peptides also inhibited fertilization similarly to xMDC16 peptides, whereas peptides corresponding to the predicted integrin-binding site of xMDC11.1 and xMDC11.2 did not. These results are discussed in the context of a model in which multiple MDC protein-receptor interactions are necessary for fertilization to occur.

Growth and male reproduction improvement of non-thermal dielectric barrier discharge plasma treatment on chickens

NASA Astrophysics Data System (ADS)

Jiao Zhang, Jiao; Luong Huynh, Do; Chandimali, Nisansala; Kang, Tae Yoon; Kim, Nameun; Mok, Young Sun; Kwon, Taeho; Jeong, Dong Kee

2018-05-01

This study investigated whether plasma treatment of fertilized eggs before hatching could affect the growth and reproduction of chickens. Three point five-day-incubated fertilized eggs exposed to non-thermal dielectric barrier discharge plasma at 2.81 W of power for 2 min resulted in the highest growth in chickens. Plasma growth-promoting effect was regulated by the reactive oxygen species homeostasis and the improvement of energy metabolism via increasing serum hormones and adenosine triphosphate levels which were resulted from the regulation of genes involved in antioxidant defense, hormone biosynthesis and energetic metabolism. Interestingly, plasma-treated male chickens conspicuously grew faster than females. Further, aspects of male reproductive system (testosterone level and sperm quality) were improved by the plasma treatment but female reproduction (estradiol and progesterone levels, egg-laying rate and egg weight) had no significant changes. Unfortunately, offspring whose parents were the optimal plasma-treated chickens did not show any difference on growth characteristics and failed to inherit excellent growth features from their parents. Our results suggest a new method to improve the growth rate and male reproductive capacity in poultry but it is only effective in the plasma direct-treated generation.

Medaka extended one-generation reproduction test evaluating 4-nonylphenol.

PubMed

Watanabe, Haruna; Horie, Yoshifumi; Takanobu, Hitomi; Koshio, Masaaki; Flynn, Kevin; Iguchi, Taisen; Tatarazako, Norihisa

2017-12-01

The medaka extended one-generation test (MEOGRT) was developed as a multigenerational toxicity test for chemicals, particularly endocrine-disrupting chemicals. Briefly, 3 generations of Japanese medaka (Oryzias latipes) are exposed to a chemical over a 20-wk period: 3 wk in the parental generation (F0), 15 wk in the first generation (F1), and 2 wk in the second generation (F2). The present study reports the first MEOGRT results concerning branched isomer mixtures of 4-nonylphenol (NP). Adult F0 medaka exposed to NP at 5 actual concentrations (1.27, 2.95, 9.81, 27.8, 89.4 µg/L) were unaffected in terms of reproduction, although vitellogenin in the male liver was increased dose-dependently at concentration of 2.95 µg/L and higher. In F1, in contrast, total egg (fecundity), fertile egg, and fertility decreased as NP increased; lowest-observed-effect concentrations (LOECs) for total egg, fertile egg, and fertility were 1.27, 1.27, 27.8 µg/L, respectively. In F1, but not in F0, secondary sex characteristics (i.e., anal fin papillae in males) were suppressed at 27.8 µg/L NP. Vitellogenin induction in adult male fish was slightly weaker in F1 than it was in F0, however. Gonadal sex abnormality and sex reversal occurred at 27.8 and 89.4 µg/L NP in F1 subadults. At 89.4 µg/L NP, all genotypic F1 males in breeding pairs had female phenotype, and some even demonstrated spawning. Concentrations of NP lower than 89.4 µg/L did not affect F2 survival or hatching. The highest detected NP level in environmental freshwater in Japan was approximately a half of the LOEC (1.27 µg/L for F1 fecundity); in other countries, however, environmental concentrations above the LOEC are reported, suggesting that NP may be affecting fish populations. Environ Toxicol Chem 2017;36:3254-3266. © 2017 SETAC. © 2017 SETAC.

Juno is the egg Izumo receptor and is essential for mammalian fertilisation

PubMed Central

Bianchi, Enrica; Doe, Brendan; Goulding, David; Wright, Gavin J.

2014-01-01

Fertilisation occurs when sperm and egg recognise each other and fuse to form a new, genetically distinct organism. The molecular basis of sperm-egg recognition is unknown, but is likely to require interactions between receptor proteins displayed on their surface. Izumo1 is an essential sperm cell surface protein, but its egg receptor has remained a mystery. Here, we identify Juno as the receptor for Izumo1 on mouse eggs, and show this interaction is conserved within mammals. Female mice lacking Juno are infertile and Juno-deficient eggs do not fuse with normal sperm. Rapid shedding of Juno from the oolemma after fertilisation suggests a mechanism for the membrane block to polyspermy, ensuring eggs normally fuse with just a single sperm. Our discovery of an essential receptor pair at the nexus of conception provides opportunities for the rational development of new fertility treatments and contraceptives. PMID:24739963

Species and gamete-specific fertilization success of two sea urchins under near future levels of pCO2

NASA Astrophysics Data System (ADS)

Sung, Chan-Gyung; Kim, Tae Won; Park, Young-Gyu; Kang, Seong-Gil; Inaba, Kazuo; Shiba, Kogiku; Choi, Tae Seob; Moon, Seong-Dae; Litvin, Steve; Lee, Kyu-Tae; Lee, Jung-Suk

2014-09-01

Since the Industrial Revolution, rising atmospheric CO2 concentration has driven an increase in the partial pressure of CO2 in seawater (pCO2), thus lowering ocean pH. We examined the separate effects of exposure of gametes to elevated pCO2 and low pH on fertilization success of the sea urchin Strongylocentrotus nudus. Sperm and eggs were independently exposed to seawater with pCO2 levels ranging from 380 (pH 7.96-8.3) to 6000 ppmv (pH 7.15-7.20). When sperm were exposed, fertilization rate decreased drastically with increased pCO2, even at a concentration of 450 ppmv (pH range: 7.94 to 7.96). Conversely, fertilization of Hemicentrotus pulcherrimus was not significantly changed even when sperm was exposed to pCO2 concentrations as high as 750 ppmv. Exposure of S. nudus eggs to seawater with high pCO2 did not affect fertilization success, suggesting that the effect of increased pCO2 on sperm is responsible for reduced fertilization success. Surprisingly, this result was not related to sperm motility, which was insensitive to pCO2. When seawater was acidified using HCl, leaving pCO2 constant, fertilization success in S. nudus remained high (> 80%) until pH decreased to 7.3. While further studies are required to elucidate the physiological mechanism by which elevated pCO2 impairs sperm and reduces S. nudus fertilization, this study suggests that in the foreseeable future, sea urchin survival may be threatened due to lower fertilization success driven by elevated pCO2 rather than by decreased pH in seawater.

Egg freezing and egg banking: empowerment and alienation in assisted reproduction.

PubMed

Robertson, John A

2014-06-01

With the development of rapid freezing of human oocytes, many programs have reported IVF success rates comparable to those achieved with fresh eggs and thawed frozen embryos. Egg freezing is now gaining professional and regulatory acceptance as a safe and effective technique for women who wish to avoid discarding excess embryos, who face fertility-threatening medical treatments, or who want to preserve their eggs for use when they are better situated to have a family. This article focuses on the uses of and justification for egg freezing, the path to professional acceptance, the variability in success rates, and the controversy over freezing eggs for social rather than medical reasons. It also addresses the emergence of egg banking as a separate sector in the infertility industry, the regulatory issues that it poses, and its effect on egg donation. Key here is the legal control of stored eggs by banking women and their options when they wish to dispose of those eggs. The analysis is framed around empowerment and alienation. Egg freezing is generally empowering for women, but the donation or sale of unused eggs to infertile women, egg bankers, and researchers also raises issues of alienation.

Egg freezing and egg banking: empowerment and alienation in assisted reproduction

PubMed Central

Robertson, John A.

2014-01-01

With the development of rapid freezing of human oocytes, many programs have reported IVF success rates comparable to those achieved with fresh eggs and thawed frozen embryos. Egg freezing is now gaining professional and regulatory acceptance as a safe and effective technique for women who wish to avoid discarding excess embryos, who face fertility-threatening medical treatments, or who want to preserve their eggs for use when they are better situated to have a family. This article focuses on the uses of and justification for egg freezing, the path to professional acceptance, the variability in success rates, and the controversy over freezing eggs for social rather than medical reasons. It also addresses the emergence of egg banking as a separate sector in the infertility industry, the regulatory issues that it poses, and its effect on egg donation. Key here is the legal control of stored eggs by banking women and their options when they wish to dispose of those eggs. The analysis is framed around empowerment and alienation. Egg freezing is generally empowering for women, but the donation or sale of unused eggs to infertile women, egg bankers, and researchers also raises issues of alienation. PMID:27774158

Artificial wetlands as tools for frog conservation: stability and variability of reproduction characteristics in Sahara frog populations in Tunisian man-made lakes.

PubMed

Bellakhal, Meher; Neveu, André; Fertouna-Bellakhal, Mouna; Aleya, Lotfi

2017-12-01

Amphibian populations are in decline principally due to climate change, environmental contaminants, and the reduction in wetlands. Even though data concerning current population trends are scarce, artificial wetlands appear to play a vital role in amphibian conservation. This study concerns the reproductive biology of the Sahara frog over a 2-year period in four Tunisian man-made lakes. Each month, gonad state (parameters: K, GSI, LCI), fecundity, and fertility of females (using 1227 clutches) were evaluated in the field under controlled conditions. Clutches were present for 110-130 days at two of the sites, but only for 60-80 days at the other two. Maximum egg laying occurred in May, corresponding to the highest point in the gonad somatic index. Clutch densities were higher in the smaller lakes. Female fecundity was in relation to body size; mean clutch fecundity attained 1416 eggs, with no differences observed according to site. Egg fertility varied over a 1-year period, with a maximum in May followed by a decrease when water temperature was at its highest. Eggs were smaller at the beginning of spawning; maximum size was in May, which might explain the higher fertility, but no maternal influence was detected. Embryonic development was strictly dependent on temperature. The population at each site appeared as a small patch within a metapopulation in overall good health, as shown by the relative temporal stability in reproduction variables. Constructed wetlands may therefore play an important role in the conservation of amphibians, especially in semi-arid zones.

A parthenogenesis gene of apomict origin elicits embryo formation from unfertilized eggs in a sexual plant

PubMed Central

Conner, Joann A.; Mookkan, Muruganantham; Huo, Heqiang; Chae, Keun; Ozias-Akins, Peggy

2015-01-01

Apomixis is a naturally occurring mode of asexual reproduction in flowering plants that results in seed formation without the involvement of meiosis or fertilization of the egg. Seeds formed on an apomictic plant contain offspring genetically identical to the maternal plant. Apomixis has significant potential for preserving hybrid vigor from one generation to the next in highly productive crop plant genotypes. Apomictic Pennisetum/Cenchrus species, members of the Poaceae (grass) family, reproduce by apospory. Apospory is characterized by apomeiosis, the formation of unreduced embryo sacs derived from nucellar cells of the ovary and, by parthenogenesis, the development of the unreduced egg into an embryo without fertilization. In Pennisetum squamulatum (L.) R.Br., apospory segregates as a single dominant locus, the apospory-specific genomic region (ASGR). In this study, we demonstrate that the PsASGR-BABY BOOM-like (PsASGR-BBML) gene is expressed in egg cells before fertilization and can induce parthenogenesis and the production of haploid offspring in transgenic sexual pearl millet. A reduction of PsASGR-BBML expression in apomictic F1 RNAi transgenic plants results in fewer visible parthenogenetic embryos and a reduction of embryo cell number compared with controls. Our results endorse a key role for PsASGR-BBML in parthenogenesis and a newly discovered role for a member of the BBM-like clade of APETALA 2 transcription factors. Induction of parthenogenesis by PsASGR-BBML will be valuable for installing parthenogenesis to synthesize apomixis in crops and will have further application for haploid induction to rapidly obtain homozygous lines for breeding. PMID:26305939

Expression of two different sulfated fucans by females of Lytechinus variegatus may regulate the seasonal variation in the fertilization of the sea urchin.

PubMed

Cinelli, Leonardo P; Castro, Michelle O; Santos, Livia L; Garcia, Clarice R; Vilela-Silva, Ana-Cristina E S; Mourão, Paulo A S

2007-08-01

The egg jellies of sea urchins contain sulfated polysaccharides with unusual structures, composed of linear chains of l-fucose or l-galactose with well-defined repetitive units. The specific pattern of sulfation and the position of the glycosidic bond vary among sulfated polysaccharides from different species. These polysaccharides show species specificity in inducing the acrosome reaction, which is a critical event for fertilization. Females of the sea urchin Lytechinus variegatus spawn eggs containing a sulfated fucan with the repetitive sequence [3-alpha-L-Fucp-2(OSO(3))-1 --> 3-alpha-L-Fucp-4(OSO(3))-1 --> 3-alpha-L-Fucp-2,4(OSO(3))-1 --> 3-alpha-L-Fucp-2(OSO(3))-1](n). We now observe that, close to winter, a period of decreased fertility for the sea urchin, the females synthesize a distinct sulfated fucan with a simple structure, composed of 4-sulfated, 3-linked alpha-fucose residues. This sulfated fucan is inactive when tested in vitro for the acrosome reaction using homologous sperm. The amount of egg jellies spawned by females (and their constituent sulfated polysaccharides) varied greatly throughout the year. Apparently, there is a correlation between the temperature of the sea water and the expression of the 4-sulfated, 3-linked sulfated fucan. Overall, we described the occurrence of two isotypes of sulfated fucan in the egg jelly of the sea urchin L. variegatus, which differ in their biological activity and may be involved in the periodicity of the reproductive cycle of the invertebrate.

Effects of Environmental Enrichment on the Fertility and Fecundity of Zebrafish (Danio rerio).

PubMed

Wafer, Lemnique N; Jensen, V Behrana; Whitney, Jesse C; Gomez, Thomas H; Flores, Rene; Goodwin, Bradford S

2016-01-01

Zebrafish (Danio rerio) are a popular vertebrate model in biomedical research, but information describing the effects of environmental enrichment on fertility and fecundity of zebrafish is sparse. In the current study, 18 breeding pairs were placed in divided 1.5-L breeding tanks containing 1 of 3 enrichment conditions: plastic grass (n = 6), plastic leaves (n = 6), or no enrichment (n = 6, control). The pairs were allowed to spawn for 3 h the next day, after which eggs were counted and breeding pairs were returned to holding tanks for use in subsequent sessions. Spawning sessions were repeated at 7-d intervals until the completion of 9 trials, with pairs rotating to a different condition at each interval. Total egg count (mean ± SEM) after 3 h was greater for zebrafish spawning in the grass environment (48.0 ± 7.7 eggs) than in the leaf or control environments (29.4 ± 5.3 and 20.4 ± 3.7 eggs, respectively). An interaction emerged between enrichment type and the age of the spawning pair on the number of fry at 6 d postfertilization (dpf). Initially, more fry were obtained from 110- and 160-dpf pairs with the grass enrichment, but from 173- and 180-dpf pairs there were more obtained with leaf enrichment than grass. A separate experiment showed that enrichment type did not have an effect on fry survivability. Overall, our data indicates that, under certain conditions, zebrafish fertility and fecundity are greater in a breeding tank containing environmental enrichment than in a bare tank.

Effect of in ovo administration of an adult-derived microbiota on establishment of the intestinal microbiome in chickens.

PubMed

Pedroso, Adriana A; Batal, Amy B; Lee, Margie D

2016-05-01

OBJECTIVE To determine effects of in ovo administration of a probiotic on development of the intestinal microbiota of 2 genetic lineages (modern and heritage) of chickens. SAMPLE 10 newly hatched chicks and 40 fertile eggs to determine intestinal microbiota at hatch, 900 fertile eggs to determine effects of probiotic on hatchability, and 1,560 chicks from treated or control eggs. PROCEDURES A probiotic competitive-exclusion product derived from adult microbiota was administered in ovo to fertile eggs of both genetic lineages. Cecal contents and tissues were collected from embryos, newly hatched chicks, and chicks. A PCR assay was used to detect bacteria present within the cecum of newly hatched chicks. Fluorescence in situ hybridization and vitality staining were used to detect viable bacteria within intestines of embryos. The intestinal microbiota was assessed by use of 16S pyrosequencing. RESULTS Microscopic evaluation of embryonic cecal contents and tissues subjected to differential staining techniques revealed viable bacteria in low numbers. Development of the intestinal microbiota of broiler chicks of both genetic lineages was enhanced by in ovo administration of adult microbiota. Although the treatment increased diversity and affected composition of the microbiota of chicks, most bacterial species present in the probiotic were transient colonizers. However, the treatment decreased the abundance of undesirable bacterial species within heritage lineage chicks. CONCLUSIONS AND CLINICAL RELEVANCE In ovo inoculation of a probiotic competitive-exclusion product derived from adult microbiota may be a viable method of managing development of the microbiota and reducing the prevalence of pathogenic bacteria in chickens.

A parthenogenesis gene of apomict origin elicits embryo formation from unfertilized eggs in a sexual plant.

PubMed

Conner, Joann A; Mookkan, Muruganantham; Huo, Heqiang; Chae, Keun; Ozias-Akins, Peggy

2015-09-08

Apomixis is a naturally occurring mode of asexual reproduction in flowering plants that results in seed formation without the involvement of meiosis or fertilization of the egg. Seeds formed on an apomictic plant contain offspring genetically identical to the maternal plant. Apomixis has significant potential for preserving hybrid vigor from one generation to the next in highly productive crop plant genotypes. Apomictic Pennisetum/Cenchrus species, members of the Poaceae (grass) family, reproduce by apospory. Apospory is characterized by apomeiosis, the formation of unreduced embryo sacs derived from nucellar cells of the ovary and, by parthenogenesis, the development of the unreduced egg into an embryo without fertilization. In Pennisetum squamulatum (L.) R.Br., apospory segregates as a single dominant locus, the apospory-specific genomic region (ASGR). In this study, we demonstrate that the PsASGR-BABY BOOM-like (PsASGR-BBML) gene is expressed in egg cells before fertilization and can induce parthenogenesis and the production of haploid offspring in transgenic sexual pearl millet. A reduction of PsASGR-BBML expression in apomictic F1 RNAi transgenic plants results in fewer visible parthenogenetic embryos and a reduction of embryo cell number compared with controls. Our results endorse a key role for PsASGR-BBML in parthenogenesis and a newly discovered role for a member of the BBM-like clade of APETALA 2 transcription factors. Induction of parthenogenesis by PsASGR-BBML will be valuable for installing parthenogenesis to synthesize apomixis in crops and will have further application for haploid induction to rapidly obtain homozygous lines for breeding.

Non-staining visualization of embryogenesis and energy metabolism in medaka fish eggs using near-infrared spectroscopy and imaging.

PubMed

Puangchit, Paralee; Ishigaki, Mika; Yasui, Yui; Kajita, Misato; Ritthiruangdej, Pitiporn; Ozaki, Yukihiro

2017-12-04

The energy metabolism and embryogenesis of fertilized Japanese medaka eggs were investigated in vivo at the molecular level using near-infrared (NIR) spectroscopy and imaging. Changes in chemical components, such as proteins and lipids, in yolk sphere and embryonic body were studied over the course of embryonic development. Metabolic changes that represent variations in the concentrations and molecular compositions of proteins and lipids in the yolk part, particularly on the 1 st day after fertilization and the day just before hatching, were successfully identified in the 4900-4000 cm -1 wavenumber region. The yolk components were shown to have specific functions at the very early and final stages of the embryonic development. Proteins with α-helix- or β-sheet-rich structures clearly showed the different variation patterns within the developing egg. Furthermore, the distribution of lipids could be selectively visualized using data from the higher wavenumber region. Detailed embryonic structures were clearly depicted in the NIR images using the data from the 6400-5500 cm -1 region in which the embryo parts had some characteristic peaks due to unsaturated fatty acids. It was made clear that yolk and embryo parts had different components especially lipid components. The present study provides new insights into material variations in the fertilized egg during its growth. NIR imaging proved to be valuable in investigating the embryogenesis in vivo at the molecular level in terms of changes in biomolecular concentrations and compositions, metabolic differentiation, and detailed information about embryonic structures without the need for staining.

Ammonia sanitization of blackwater for safe use as fertilizer.

PubMed

Fidjeland, Jörgen; Svensson, Sven-Erik; Vinnerås, Björn

2015-01-01

Source-separated blackwater from low-flush toilets contains plant-available nutrients and can be used as a fertilizer. The aim of the study was to evaluate the impact on pathogen inactivation when treating blackwater with urea and/or lime. Blackwater was spiked with Salmonella typhimurium, Escherichia coli O157, Enterococcus faecalis, and Ascaris suum eggs, and treated with urea and/or lime in concentrations up to 0.1% w/w. The bottles were kept in a storage facility (manure slurry tank) for 102 days while monitoring the pathogen concentrations. The treatment time needed to meet the requirement for Salmonella and E. coli reduction could be reduced at least six-fold. The enterococci were more persistent, and only the highest treatment doses had a significantly higher inactivation than the controls. The Ascaris egg viability was only reduced by around 50%, so higher urea/lime doses and/or longer treatment times are required to fulfill the treatment requirements of 3 log10 reductions of parasite eggs.

Potential of Lactobacillus plantarum IBB3036 and Lactobacillus salivarius IBB3154 to persistence in chicken after in ovo delivery.

PubMed

Aleksandrzak-Piekarczyk, Tamara; Puzia, Weronika; Żylińska, Joanna; Cieśla, Jarosław; Gulewicz, Krzysztof A; Bardowski, Jacek K; Górecki, Roman K

2018-03-25

The aim of this study was to characterize and compare selected Lactobacillus strains originating from different environments (cow milk and hen feces) with respect to their applicative potential to colonize gastrointestinal track of chickens before hatching from an egg. In vitro phenotypic characterization of lactobacilli strains included the investigation of the important prerequisites for persistence in gastrointestinal tract, such as a capability to survive in the presence of bile salts and at low pH, enzymatic and sugar metabolic profiles, adhesion abilities, and resistance to osmolytes, temperature, and antibiotics. Regarding the resistance of lactobacilli to most of the various stress factors tested, the milk isolate Lactobacillus plantarum IBB3036 showed better abilities than the chicken feces isolate Lactobacillus salivarius IBB3154. However, regarding the acidification tolerance and adherence ability, L. salivarius IBB3154 revealed better characteristics. Use of these two selected lactobacilli isolates together with proper prebiotics resulted in the preparation of two S1 and S2 bioformulations, which were injected in ovo into hen Cobb500 FF fertilized eggs. Furthermore, in vivo tests assessing the persistence of L. plantarum IBB3036 and L. salivarius IBB3154 in the chicken gastrointestinal tract was monitored by PCR-based classical and quantitative techniques and revealed the presence of both strains in fecal samples collected 3 days after hatching. Subsequently, the number of L. salivarius IBB3154 increased significantly in the chicken intestine, whereas the presence of L. plantarum IBB3036 was gradually decreased. © 2018 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Greenhouse Studies of Thiamethoxam Effects on Pea Leaf Weevil, Sitona lineatus

PubMed Central

Cárcamo, Héctor; Herle, Carolyn; Hervet, Vincent

2012-01-01

The pea leaf weevil, Sitona lineatus L. (Coleoptera: Curculionidae), has recently emerged as an important pest of field peas in the Canadian prairies. Systemic seed-coated insecticides may provide a tool for the integrated pest management of this pest. Therefore, several controlled assays were performed in order to determine effects of a recently registered neonicotinoid, (thiamethoxam) on S. lineatus damage to foliage, weevil mortality, fertility, egg viability, larval mortality, and root nodule damage. Foliage damage was reduced by thiamethoxam relative to untreated controls during the seedling stage (2nd–5th nodes), but weevil adult mortality was only 15–30%. Fertility was reduced substantially through an extra seven-day delay in the preoviposition period and reduced egg-laying rate during the first 20 days of the study (92% lower than controls). Overall egg viability was lower in females fed foliage grown from thiamethoxamtreated seeds. Larval survivorship and nodule damage were also lower, but only when eggs were added to treated plants at the 2nd node stage. When eggs were added late, at the 5th node stage, thiamethoxam had no effect on larval survivorship or nodule damage. The results of this study led to the conclusion that seed treatments such as thiamethoxam have potential to be used as tools that will aid in the integrated pest management of S. lineatus, especially in combination with other methods such as biocontrol and trap crops. PMID:23461362

Effects of methoprene, a juvenile hormone analog, on survival of various developmental stages, adult emergence, reproduction and behavior of Asian citrus psyllid, Diaphorina citri Kuwayama.

PubMed

Brar, Gurpreet S; Meyer, Wendy; Stelinski, Lukasz L

2015-12-01

The Asian citrus citrus psyllid, Diaphorina citri Kuwayama, transmits a bacterium that causes huanglongbing in citrus. Frequent and repeated use of neurotoxic insecticides against D. citri has resulted in the development of insecticide resistance. We evaluated the effects of the juvenile hormone analog methoprene on egg hatch, nymphal development, adult emergence, reproduction and behavior of D. citri. Methoprene significantly reduced the viability of eggs that were between 0 and 4 days old. Egg hatch of 0-48-h-old and 49-96-h-old eggs was 8 and 9%, respectively, when treated with 320 µg mL(-1) of methoprene. Methoprene caused significant mortality of first-, third- and fifth-instar D. citri nymphs and reduced adult emergence as compared with controls. Methoprene caused less than 5% adult emergence when first- and third-instar stages were treated, respectively, and less than 40% adult emergence when fifth instars were treated. Reduced fertility of females was observed when they emerged from methoprene-treated fifth instars. Methoprene was effective in reducing egg hatch, suppressing nymphal development and decreasing adult emergence of D. citri under laboratory conditions. Treatment of fifth instars reduced the fertility of females. Methoprene might be a possible tool for integrated management of D. citri. © 2015 Society of Chemical Industry.

Eggs-ploiting women: a critical feminist analysis of the different principles in transplant and fertility tourism.

PubMed

Pfeffer, Naomi

2011-11-01

Intergovernmental agencies have recognized that inconsistencies in the way that nation states regulate commerce in human kidneys lubricate transplant tourism, and have repeatedly exhorted recalcitrant governments of both organ-importing and organ-exporting nations to criminalize the exchange of cash for kidneys. Yet these same organizations have elected to remain silent on inconsistencies in the regulation of the trade in human eggs that lubricate fertility tourism. This article is a critical feminist analysis of this paradox. Sketches of the histories of regulation of the global markets in human kidneys and human eggs allow attribution of the different approaches to sales of kidneys and eggs to the triumph of neo-liberalism in the 1990s. Neo-liberalism supports the growth of the medical tourism industry and its niche market catering for infertility, and is responsible for exacerbating the relative disadvantage of poor and powerless women in destination countries, thereby creating the conditions for 'bioavailability', that is, the willingness to exchange body parts for cash. The paper identifies a disturbing correlation between deeply engrained conservative attitudes to women and a plentiful supply of eggs, and concludes by suggesting that what women need to lift themselves out of poverty and discrimination is secure and dignified work. Copyright © 2011 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Pre-implantation diagnosis of aneuploidy by polar body and blastomere FISH analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Munne, S.; Cohen, J.; Grifo, J.

1994-09-01

For preimplantation genetic diagnosis (PGD) of aneuploidy in human in-vitro fertilization (IVF), two blastomeres per embryo should be analyzed to minimize errors caused by FISH and mosaicism. But the biopsy of two cells from an 8-cell embryo can be detrimental. This can be substituted by initial FISH analysis of the first polar body (PB) and subsequent single blastomere analysis. Simultaneous FISH analysis of chromosomes X, Y, 18, 13/21 was used for first polar body aneuploidy analysis. Normal divalents appeared as single-dotted signals corresponding to their two chromatids. We found that pre-division of chromatids increased dramatically with time in culture. Allmore » but three pre-division events involved separation of chromatids within the PB or the egg, with a total of two chromatids in each. We concluded that PB aneuploidy analysis is safe when performed within 6 hours after egg retrieval. For our first clinical case we chose a 39 year-old female carrier of an X-linked disease already selected for FISH pre-implantation diagnosis. Eight polar bodies from 12 eggs were analyzed: six showed a normal X181321 complement of divalents; one had an extra chromatid for 13/21 (egg {number_sign}8); and one had a missing chromatid for 13/21 (egg {number_sign}10). After insemination, six fertilized eggs developed into embryos, including egg {number_sign}10 but not egg {number_sign}8. At day 3 of development, a single blastomere per embryo was analyzed by FISH. According to the blastomere analysis, one embryo was haploid, one tetraploid. The two normal female embryos were replaced and pregnancy and CFS results are pending. These results suggest that this technique can be successfully applied for PGD of major aneuploidies in IVF patients over 35. In addition, it indicates that studies on pre-division should be performed on eggs within six hours of retrieval.« less

Fertility signals in the bumblebee Bombus terrestris (Hymenoptera: Apidae)

NASA Astrophysics Data System (ADS)

Sramkova, A.; Schulz, C.; Twele, R.; Francke, W.; Ayasse, M.

2008-06-01

In eusocial Hymenoptera, queen control over workers is probably inseparable from the mechanism of queen recognition. In primitively eusocial bumblebees ( Bombus), worker reproduction is controlled not only by the presence or absence of a dominant queen but also by other dominant workers. Furthermore, it was shown that the queen dominance is maintained by pheromonal cues. We investigated whether there is a similar odor signal released by egg-laying queens and workers that may have a function as a fertility signal. We collected cuticular surface extracts from nest-searching and breeding Bombus terrestris queens and workers that were characterized by their ovarian stages. In chemical analyses, we identified 61 compounds consisting of aldehydes, alkanes, alkenes, and fatty acid esters. Nest-searching queens and all groups of breeding females differed significantly in their odor bouquets. Furthermore, workers before the competition point (time point of colony development where workers start to develop ovaries and lay eggs) differed largely from queens and all other groups of workers. Breeding queens showed a unique bouquet of chemical compounds and certain queen-specific compounds, and the differences toward workers decrease with an increasing development of the workers’ ovaries, hinting the presence of a reliable fertility signal. Among the worker groups, the smallest differences were found after the competition point. Egg-laying females contained higher total amounts of chemical compounds and of relative proportions of wax-type esters and aldehydes than nest-searching queens and workers before the competition point. Therefore, these compounds may have a function as a fertility signal present in queens and workers.

Duplicate Abalone Egg Coat Proteins Bind Sperm Lysin Similarly, but Evolve Oppositely, Consistent with Molecular Mimicry at Fertilization

PubMed Central

Aagaard, Jan E.; Springer, Stevan A.; Soelberg, Scott D.; Swanson, Willie J.

2013-01-01

Sperm and egg proteins constitute a remarkable paradigm in evolutionary biology: despite their fundamental role in mediating fertilization (suggesting stasis), some of these molecules are among the most rapidly evolving ones known, and their divergence can lead to reproductive isolation. Because of strong selection to maintain function among interbreeding individuals, interacting fertilization proteins should also exhibit a strong signal of correlated divergence among closely related species. We use evidence of such molecular co-evolution to target biochemical studies of fertilization in North Pacific abalone (Haliotis spp.), a model system of reproductive protein evolution. We test the evolutionary rates (d N/d S) of abalone sperm lysin and two duplicated egg coat proteins (VERL and VEZP14), and find a signal of co-evolution specific to ZP-N, a putative sperm binding motif previously identified by homology modeling. Positively selected residues in VERL and VEZP14 occur on the same face of the structural model, suggesting a common mode of interaction with sperm lysin. We test this computational prediction biochemically, confirming that the ZP-N motif is sufficient to bind lysin and that the affinities of VERL and VEZP14 are comparable. However, we also find that on phylogenetic lineages where lysin and VERL evolve rapidly, VEZP14 evolves slowly, and vice versa. We describe a model of sexual conflict that can recreate this pattern of anti-correlated evolution by assuming that VEZP14 acts as a VERL mimic, reducing the intensity of sexual conflict and slowing the co-evolution of lysin and VERL. PMID:23408913

Dimorphic ejaculates and sperm release strategies associated with alternative mating behaviors in the squid.

PubMed

Apostólico, Lígia H; Marian, José E A R

2017-11-01

Sperm competition is a powerful postcopulatory selective force influencing male adaptations associated with increasing fertilization success, and it is usually related to the evolution of different strategies of ejaculate expenditure between individuals. Ejaculates may also be influenced by additional selective pressures associated with sperm competition, such as timing between insemination and fertilization, female reproductive tract morphology, and fertilization environment. Also, males that adopt alternative mating tactics may face distinct sperm competition pressures, which may lead to the evolution of intraspecific diversity in ejaculates. In loliginid squids, males with alternative reproductive tactics (sneakers and consorts) differ not only in mating behavior, but also transfer spermatophores into two distinct sites within the female. Here, we compared structure and functioning of spermatophores between sneakers and consorts in the squid Doryteuthis plei applying microscopy techniques and in vitro experiments. Sneakers and consorts exhibit differences in spermatophore structure that lead to distinct spermatophoric reactions and spermatangium morphologies. Moreover, in sneakers, sperm release lasts longer and their sperm show an aggregative behavior not detected in consorts. Slow sperm release may be a strategy to guarantee longer sperm provision, given the wide interval between sneaker mating and egg release. For consorts, in turn, intense and quick sperm discharge may be advantageous, as timing between mating and egg-laying is relatively short. Within the complex squid mating system, factors such as (i) different fertilization sites and (ii) interval between mating and egg release may also influence sperm competition, and ultimately shape the evolution of divergent ejaculates between dimorphic males. © 2017 Wiley Periodicals, Inc.

Effective freezing rate for semen cryopreservation in endangered Mediterranean brown trout (Salmo trutta macrostigma) inhabiting the Biferno river (South Italy).

PubMed

Iaffaldano, Nicolaia; Di Iorio, Michele; Manchisi, Angelo; Esposito, Stefano; Gibertoni, Pier Paolo

2016-10-01

This study was designed to determine: (i) the in vitro effects of different freezing rates on post-thaw semen quality of Mediterranean brown trout (Salmo trutta macrostigma) from the Biferno river; and (ii) the in vivo fertilization and hatching percentage of freezing rate giving rise to the best post-thaw semen quality. Pooled semen samples were diluted 1:3 (v:v) in a freezing extender composed of 300 mM glucose, 10% egg yolk and 10% dimethyl sulfoxide (DMSO). The extended semen was packaged in 0.25 ml plastic straws and frozen at different heights above the liquid nitrogen surface (1, 5 or 10 cm) for 10 min to give three different freezing rates. Semen samples were thawed at 30°C for 10 s. The variables assessed after thawing were sperm motility, duration of motility and viability. Our results clearly indicate a significant effect of freezing rate on post-thaw semen quality. Semen frozen 5 cm above the liquid nitrogen surface showed the best quality after freezing/thawing. Based on these in vitro data, 2 groups of 200 eggs were fertilized with fresh semen or semen frozen 5 cm above the liquid nitrogen surface. Fertilization and hatching rates recorded for eggs fertilized with frozen semen were significantly lower (25.4% and 22.5%, respectively) than the ones obtained using fresh semen (87.8% and 75.5%, respectively). An effective freezing protocol will allow for the creation of a sperm cryobank to recover the original population of Mediterranean brown trout in the Biferno river.

EGG-4 and EGG-5 link events of the oocyte-to-embryo transition with meiotic cell cycle progression in Caenorhabditis elegans

PubMed Central

Parry, Jean M.; Velarde, Nathalie V.; Lefkovith, Ariel J.; Zegarek, Matthew H.; Hang, Julie S.; Ohm, Jonathan; Klancer, Richard; Maruyama, Rika; Druzhinina, Marina K.; Grant, Barth D.; Piano, Fabio; Singson, Andrew

2009-01-01

Summary The molecular underpinnings of the oocyte-to-embryo transition are poorly understood. Here we show that two protein tyrosine phosphatase-like (PTPL) family proteins, EGG-4 and EGG-5, are required for key events of the oocyte-to-embryo transition in Caenorhabditis elegans. The predicted EGG-4 and EGG-5 amino acid sequences are 99% identical and their functions are redundant. In embryos lacking EGG-4 and EGG-5 we observe defects in meiosis, polar body formation, the block to polyspermy, F-actin dynamics, and eggshell deposition. During oogenesis, EGG-4 and EGG-5 assemble at the oocyte cortex with the previously identified regulators or effectors of the oocyte-to-embryo transition EGG-3, CHS-1 and MBK-2 [1, 2]. All of these molecules share a complex interdependence with regards to their dynamics and subcellular localization. Shortly after fertilization, EGG-4 and EGG-5 are required to properly coordinate a redistribution of CHS-1 and EGG-3 away from the cortex during meiotic anaphase I. Therefore EGG-4 and EGG-5 are not only required for critical events of the oocyte-to-embryo transition but also link the dynamics of the regulatory machinery with the advancing cell cycle. PMID:19879147

A libertarian perspective on the stem cell debate: compromising the uncompromisible.

PubMed

Block, Walter

2010-08-01

The present paper attempts to forge a compromise between those who maintain that stem cell research is out-and-out murder of young helpless human beings and those who favor this practice. The compromise is predicated upon the libertarian theory of private property rights. Starting out with the premise that not only the fetus but even the fertilized egg is a human being, with all rights thereto, it offers a competition between those who fertilize eggs for research and those who wish to adopt them. If and only if the former win this competition will they be allowed to use these very young human beings for the purposes they have constructed them. This is justified on grounds of avoiding child abuse.

Reproductive performance of breeder quails fed diets supplemented with L-cysteine-coated iron oxide nanoparticles.

PubMed

Mohammadi, H; Farzinpour, A; Vaziry, A

2017-04-01

The objective of this study was to investigate the effects of L-cysteine-coated iron oxide nanoparticles on reproductive performance in breeder quails. The five treatment diets consisted of (i) negative control diet not supplemented with iron, (ii) positive control diet supplemented with 60 mg/kg of Fe 3 O 4 and (iii) experimental diets supplemented with 0.6, 6 and 60 mg/kg of L-cysteine-coated iron oxide nanoparticles. A total of 100 seven-day-old quail chicks were weighed and randomly placed to five groups of five replicate cages. Four quails (one male and three females) were raised in each cage (50 × 15 × 17 cm). Egg production, feed consumption and egg weight were recorded daily and calculated on a hen per day basis. Egg components, fertility, hatchability and day-old chicks hatched from their eggs were measured at the end of the experiment. The percentage of egg production and egg mass of the 6 mg/kg Fe 3 O 4 -Cys NPs group were significantly higher than those of the control groups. Throughout the experimental period, the highest weekly egg weight was recorded for the 60 mg/kg Fe 3 O 4 -Cys NPs group. Fertility was improved by diet supplemented with iron, both FeSO 4 and Fe 3 O 4 -Cys NPs. The breeder fed Fe 3 O 4 -Cys NPs had the highest day-old chicks weight. The results of this study showed that Fe 3 O 4 nanoparticles that were coated by L-cysteine could improve availability and utilization of iron in diet. Finally, it was proposed that Fe 3 O 4 -Cys NPs could be used as feed additives in quails. © 2017 Blackwell Verlag GmbH.

TRPV3 channels mediate strontium-induced mouse egg activation

PubMed Central

Carvacho, Ingrid; Lee, Hoi Chang; Fissore, Rafael A.; Clapham, David E.

2014-01-01

SUMMARY In mammals, calcium influx is required for oocyte maturation and egg activation. The molecular identities of the calcium-permeant channels that underlie the initiation of embryonic development are not established. Here, we describe a Transient Receptor Potential (TRP) ion channel current activated by TRP agonists that is absent in TrpV3−/− eggs. TRPV3 current is differentially expressed during oocyte maturation, reaching a peak of maximum density and activity at metaphase of meiosis II (MII), the stage of fertilization. Selective activation of TRPV3 channels provokes egg activation by mediating massive calcium entry. Widely used to activate eggs, strontium application is known to yield normal offspring in combination with somatic cell nuclear transfer. We show that TRPV3 is required for strontium influx, as TrpV3−/− eggs failed to permeate Sr2+ or undergo strontium-induced activation. We propose that TRPV3 is the major mediator of calcium influx in mouse eggs and is a putative target for artificial egg activation. PMID:24316078

Effects of calcium and magnesium hardness on the fertilization and hatching success of channel X blue hybrid catfish eggs

USDA-ARS?s Scientific Manuscript database

The aquifer used for hybrid catfish hatcheries is less than 10 mg/L of calcium hardness and 1- 25 mg/L of magnesium hardness. Embryonic development is deemed to be the most sensitive stage in the life cycle of a teleost. As egg development takes outside the fish’s body, water hardness is one abioti...

A Classroom Activity Debating the Ethical Issues of Preimplantation Genetic Diagnosis: A Role-Playing Exercise

ERIC Educational Resources Information Center

Staddon, William

2008-01-01

Almost three decades ago, the birth of Louise Brown in England marked the beginning of the "in vitro" fertilization (IVF) era. IVF is done to overcome infertility problems that some couples experience. Sperm and eggs are collected and fertilized in the lab. ("In vitro" means "in glass" and is used to refer to…

Sneaker "jack" males outcompete dominant "hooknose" males under sperm competition in Chinook salmon (Oncorhynchus tshawytscha).

PubMed

Young, Brent; Conti, David V; Dean, Matthew D

2013-12-01

In a variety of taxa, males deploy alternative reproductive tactics to secure fertilizations. In many species, small "sneaker" males attempt to steal fertilizations while avoiding encounters with larger, more aggressive, dominant males. Sneaker males usually face a number of disadvantages, including reduced access to females and the higher likelihood that upon ejaculation, their sperm face competition from other males. Nevertheless, sneaker males represent an evolutionarily stable strategy under a wide range of conditions. Game theory suggests that sneaker males compensate for these disadvantages by investing disproportionately in spermatogenesis, by producing more sperm per unit body mass (the "fair raffle") and/or by producing higher quality sperm (the "loaded raffle"). Here, we test these models by competing sperm from sneaker "jack" males against sperm from dominant "hooknose" males in Chinook salmon. Using two complementary approaches, we reject the fair raffle in favor of the loaded raffle and estimate that jack males were ∼1.35 times as likely as hooknose males to fertilize eggs under controlled competitive conditions. Interestingly, the direction and magnitude of this skew in paternity shifted according to individual female egg donors, suggesting cryptic female choice could moderate the outcomes of sperm competition in this externally fertilizing species.

Embryotoxicity of Corexit 9500 in mallard ducks (Anas platyrhynchos).

PubMed

Wooten, Kimberly J; Finch, Bryson E; Smith, Philip N

2012-04-01

Embryotoxicity of the oil dispersant Corexit 9500 was examined using fertilized mallard duck eggs. Corexit 9500 was topically applied below the air cell to eggs in volumes ranging from 0 to 100 μL on day 3 of incubation. The highest incidence of mortality occurred at developmental stage 4, one day post-Corexit 9500 application. Hatching success was significantly decreased among eggs treated with ≥ 20 μL of Corexit 9500 as compared to controls (P ≤ 0.047). No egg treated with ≥ 40 μL successfully hatched. The application volume resulting in 50% mortality (corrected for control survival) was determined to be 15.5 μL. Developmental stage at embryo death was also significantly decreased compared to controls in eggs exposed to 40 μL (P = 0.0042) and above.

Embryology of Maldives clownfish, Amphiprion nigripes (Amphiprioninae)

NASA Astrophysics Data System (ADS)

Ghosh, Swagat; Kumar, Thipramalai Thankappanpillai Ajith; Balasubramanian, Thangavel

2012-06-01

This study investigated the embryonic development of Maldives clownfish Amphiprion nigripes under natural conditions (28-30°C) at a lagoon of Agatti Island, Lakshadweep, India. The newly deposited fish egg was capsule-shaped and orange-red, with a (0.73 ± 0.04) mm3 yolk containing 5-10 fat globules. The embryonic development of fertilized eggs was divided into 26 stages and the time elapsing for each stage was recorded. Results showed that the cleavage was rapid, with the first division observed 1 h 20 min after fertilization. Blastulation occurred 4 h later, followed by gastrulation 12 h after fertilization, with a yolk volume of (0.61 ± 0.06) mm3. The organogenesis process started 22 h after fertilization when the blastopores closed and notochord formation began. The embryonic stage was recorded 24 h later, with the appearance of forebrain, midbrain, hindbrain, melanophores on yolk-sac and 22 somites, and a decreased yolk volume of (0.54 ± 0.08) mm3. Other organs developed well 31 h after fertilization, whereas the heart started beating and blood circulation began 78 h later. Red pigmentation (erytrophores) appeared 96 h after fertilization, with a small yolk volume of (0.22 ± 0.02) mm3. Mouth developed well and eyes were noticeable 120 h later, with head, pectoral fin and tail frequently moving 144 h after fertilization. The embryo reached the pre-hatching stage 168 h later and started to hatch after 170-180 h incubation. This study first detailed the embryonic development and yolk absorption of A. nigripes under natural conditions.

Comparative biology of sperm factors and fertilization-induced calcium signals across the animal kingdom.

PubMed

Kashir, Junaid; Deguchi, Ryusaku; Jones, Celine; Coward, Kevin; Stricker, Stephen A

2013-10-01

Fertilization causes mature oocytes or eggs to increase their concentrations of intracellular calcium ions (Ca²⁺) in all animals that have been examined, and such Ca²⁺ elevations, in turn, provide key activating signals that are required for non-parthenogenetic development. Several lines of evidence indicate that the Ca²⁺ transients produced during fertilization in mammals and other taxa are triggered by soluble factors that sperm deliver into oocytes after gamete fusion. Thus, for a broad-based analysis of Ca²⁺ dynamics during fertilization in animals, this article begins by summarizing data on soluble sperm factors in non-mammalian species, and subsequently reviews various topics related to a sperm-specific phospholipase C, called PLCζ, which is believed to be the predominant activator of mammalian oocytes. After characterizing initiation processes that involve sperm factors or alternative triggering mechanisms, the spatiotemporal patterns of Ca²⁺ signals in fertilized oocytes or eggs are compared in a taxon-by-taxon manner, and broadly classified as either a single major transient or a series of repetitive oscillations. Both solitary and oscillatory types of fertilization-induced Ca²⁺ signals are typically propagated as global waves that depend on Ca²⁺ release from the endoplasmic reticulum in response to increased concentrations of inositol 1,4,5-trisphosphate (IP₃). Thus, for taxa where relevant data are available, upstream pathways that elevate intraoocytic IP3 levels during fertilization are described, while other less-common modes of producing Ca²⁺ transients are also examined. In addition, the importance of fertilization-induced Ca²⁺ signals for activating development is underscored by noting some major downstream effects of these signals in various animals. © 2013 Wiley Periodicals, Inc.

Sperm competition, but not major histocompatibility divergence, drives differential fertilization success between alternative reproductive tactics in Chinook salmon.

PubMed

Lehnert, S J; Helou, L; Pitcher, T E; Heath, J W; Heath, D D

2018-01-01

Post-copulatory sexual selection processes, including sperm competition and cryptic female choice (CFC), can operate based on major histocompatibility (MH) genes. We investigated sperm competition between male alternative reproductive tactics [jack (sneaker) and hooknose (guard)] of Chinook salmon (Oncorhynchus tshawytscha). Using a full factorial design, we examined in vitro competitive fertilization success of paired jack and hooknose males at three time points after sperm activation (0, 15 and 60 s) to test for male competition, CFC and time effects on male fertilization success. We also examined egg-mediated CFC at two MH genes by examining both the relationship between competitive fertilization success and MH divergence as well as inheritance patterns of MH alleles in resulting offspring. We found that jacks sired more offspring than hooknose males at 0 s post-activation; however, jack fertilization success declined over time post-activation, suggesting a trade-off between sperm speed and longevity. Enhanced fertilization success of jacks (presumably via higher sperm quality) may serve to increase sneaker tactic competitiveness relative to dominant hooknose males. We also found evidence of egg-mediated CFC (i.e. female × male interaction) influencing competitive fertilization success; however, CFC was not acting on the MH genes as we found no relationship between fertilization success and MH II β 1 or MH I α 1 divergence and we found no deviations from Mendelian inheritance of MH alleles in the offspring. Our study provides insight into evolutionary mechanisms influencing variation in male mating success within alternative reproductive tactics, thus underscoring different strategies that males can adopt to attain success. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Fertilized eggs obtained from transplantation of frozen ovaries and parthenogenesis in combination with artificial insemination of frozen semen of the silkworm, Bombyx mori.

PubMed

Mochida, Yuji; Takemura, Yoko; Kanda, Toshio; Horie, Yasuhiro

2003-04-01

A reliable method is reported for the long-term preservation of ovaries and spermatozoa of the silkworm (Bombyx mori). Three studies are presented. In the first, ovaries were removed from larvae at either 3rd, 4th, or 5th instar, cryopreserved, and stored in liquid nitrogen. Thawed ovaries were transplanted to surgically castrated female larvae at the same or a different developmental stage. The highest percentage of recipient females producing eggs resulted into either 3rd or 4th instar larvae (respectively, 22.1 and 8.7%). Similarly, the highest levels of other measurements of successful cryopreservation and transplanted ovary, and number of eggs laid, occurred with the same combination of donor and recipient developmental stages. Other combinations of ovary/recipient developmental stages yielded lower results. In the second experiment, semen was collected from male moths, cryopreserved, and then thawed semen was diluted with trypsin solution and artificially inseminated into females obtained from the best conditions of first experiment. A small percentage of inseminated moths laid eggs (8-10.3%) compared to that of controls (100%). In addition, the fertility of eggs from experimental moths was lower than that of control females (respectively, 40.3-88% and 97.5%). In the third experiment, eggs were surgically removed from ovarian tubules of moth following transplantation of thawed ovaries and subjected to parthenogenetic activation and artificial hatching. As expected, all resulting moths were female and, following natural mating or artificial insemination with thawed semen, yielded normal offspring at high rates.

From the epididymis to the egg: participation of CRISP proteins in mammalian fertilization.

PubMed

Da Ros, Vanina G; Muñoz, Mariana Weigel; Battistone, Maria A; Brukman, Nicolás G; Carvajal, Guillermo; Curci, Ludmila; Gómez-ElIas, MatIas D; Cohen, D Bora J; Cuasnicu, Patricia S

2015-01-01

Mammalian fertilization is a complex process that involves different steps of interaction between the male and female gametes. In spite of its relevance, the molecular mechanisms underlying this process still remain to be elucidated. The present review describes the contribution of our laboratory to the understanding of mammalian fertilization using Cysteine-RIch Secretory Proteins (CRISP) as model molecules. Substantial evidence obtained from in vitro assays and knockout models shows that epididymal CRISP1 associates with the sperm surface with two different affinities during maturation, and participates in the regulation of signaling pathways during capacitation as well as in both sperm-zona pellucida interaction and gamete fusion. These observations can be extended to humans as judged by our findings showing that the human homolog of the rodent protein (hCRISP1) is also involved in both stages of fertilization. Evidence supports that other members of the CRISP family secreted in the testis (CRISP2), epididymis (CRISP3-4) or during ejaculation (CRISP3) are also involved in sperm-egg interaction, supporting the existence of a functional redundancy and cooperation between homolog proteins ensuring the success of fertilization. Together, our observations indicate that CRISP proteins accompany spermatozoa along their transit through both the male and female reproductive tracts. We believe these results not only contribute to a better mechanistic understanding of fertilization but also support CRISP proteins as excellent candidates for future research on infertility and contraception.

Your First Gynecologic Visit

MedlinePlus

... when an egg is not fertilized (also called menstruation). Obstetrician–Gynecologist (Ob–Gyn): A physician with special skills, training, and education in women’s health. Pap Test: A test in ...

Fertility of boar semen cryopreserved in extender supplemented with butylated hydroxytoluene.

PubMed

Trzcińska, Monika; Bryła, Magdalena; Gajda, Barbara; Gogol, Piotr

2015-02-01

The present study was to determine the effect of butylated hydroxytoluene (BHT) on quality and fertilizing ability of frozen-thawed boar semen. In the first experiment, five crossbreds of Polish Landrace and Large White boars (five ejaculates per boar) were frozen in 0.5 mL straws after dilution with lactose-egg yolk-glycerol extender supplemented with 0 (control), 0.5, 1.0, and 2.0 mM BHT. The sperm quality was verified based on the motility (computer-assisted sperm analysis; total motility, %; progressive motility, %), membrane integrity (YO-PRO-1/propidium iodide [PI] assay), acrosome integrity (fluorescein isothiocyanate-conjugated with peanut agglutinin/PI), and lipid peroxidation (chemiluminescence method) at 15 minutes postthaw. In the second experiment, the semen cryopreserved in extender supplemented with 1.0 and 2.0 mM BHT were selected for intrauterine artificial insemination of synchronized gilts. An intrauterine artificial insemination with low numbers of spermatozoa (500 × 10(6)) was surgically infused into each uterine horn. The highest (P < 0.001) progressive motility (%), membrane integrity, and acrosomal integrity were noted by the addition of 1.0 and 2.0 mM BHT to the freezing extender. Moreover, the various concentrations (0.5-2.0 mM) of BHT caused a considerable decrease in lipid peroxidation in relation to the control extender (P < 0.001). The highest reproductive performance of inseminated gilts (farrowing rate, 86.7%; litter size, 10.8 ± 1.6) was observed when semen was cryopreserved in extender supplemented with 1.0 mM BHT. These findings demonstrate that the addition of 1.0 mM BHT to the freezing extender efficiently improves the fertilizing ability of postthaw boar spermatozoa. Copyright © 2015 Elsevier Inc. All rights reserved.

Psychological Counseling of Female Fertility Preservation Patients

PubMed Central

Lawson, Angela K.; Klock, Susan C.; Pavone, Mary Ellen; Hirshfeld-Cytron, Jennifer; Smith, Kristin N.; Kazer, Ralph R.

2015-01-01

Young cancer patients are increasingly interested in preserving their fertility prior to undergoing gonadotoxic therapies. Although the medical safety and treatment protocols for fertility preservation have been well documented, limited research has addressed the emotional issues which arise in fertility preservation patients. We briefly review the literature on the psychosocial issues in adult female fertility preservation treatment and describe our experiences within this patient population patient. Our findings suggest that several important issues to be addressed during the psychological counseling of adult female fertility preservation patients include: 1) pre-existing psychological distress in patients undergoing treatment, 2) choice of fertility preservation strategy in the face of an uncertain relationship future, 3) decision making regarding use of third party reproduction (e.g., sperm/egg donation, gestational surrogacy), 4) treatment expectations regarding pregnancy and miscarriage, 5) ethical issues related to treatment including the creation, cryopreservation, and disposition of embryos/oocytes, and 6) decision regret from patients who declined fertility preservation. PMID:25996581

The formation of zona radiata in Pseudosciaena crocea revealed by light and transmission electron microscopy.

PubMed

Ma, Xiao-Xin; Zhu, Jun-Quan; Zhou, Hong; Yang, Wan-Xi

2012-02-01

The egg envelope is an essential structure occurring during oogenesis. It plays an important role during the process of fertilization in the large yellow croaker Pseudosciaena crocea. Elucidation of egg envelope formation helps us to understand fertilization mechanisms in teleosts. In the present work, we studied the formation of egg envelope in P. crocea by light microscopy, as well as by transmission and scanning electron microscopy. Four layers exist outside the oocyte plasmalemma, i.e., theca cell layer, basal membrane, granulosa cell layer and zona radiata. According to our observation, zona radiata is a multilaminar structure just like the same structure reported in teleosts, but the origin of this structure is a little different. Before it is formed, a peripheral space filled with different density of vesicles is the place where zona radiata is formed. Zona radiata (Z1) is secreted only by oocyte itself, it belongs to the primary envelope; zona radiata 2 (Z2) and zona radiata 3 (Z3) belong to the secondary envelope, because the two layers are formed after granulosa cells appear, and microvilli participate this process. It is very interesting that Z2 and Z3 are situated between Z1 and the granulosa cell first, but they translocate to the other side of Z1. This microanatomy difference may due to the participation of microvilli. The new finding about egg envelope formation in P. crocea will help us to do further investigation on fertilization mechanisms and will make artificial breeding possible which may contribute to the resource recovery of this species. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of dosage and application mode of L-carnitine on plasma lipid and egg-yolk cholesterol of turkeys, hatchability of eggs and post-hatch growth of their offsprings.

PubMed

Oso, A O; Fafiolu, A O; Adeleke, M A; Ladokun, O A; Sobayo, R A; Jegede, A V; Peters, S O; Oyebamiji, O A; Akinsola, J

2014-08-01

The effect of dosage and application mode of L-carnitine on plasma lipid and egg-yolk cholesterol of breeder turkeys, hatchability of eggs and post-hatch growth response was investigated using 180 breeder hens. The hens were assigned to six dietary treatments in a 2 × 3 factorial arrangements of two application modes of L-carnitine (diet and drinking water) supplemented at 0, 50 and 100 ppm (mg/kg or mg/l) levels, respectively. Each treatment was replicated five times with six hens per replicate. Dietary inclusion of 50 ppm L-carnitine showed the lowest (p < 0.01) plasma total cholesterol (TC) and low-density lipoprotein concentration (LDL). Breeder hens offered 50 ppm L-carnitine with no regard to application mode recorded the highest (p < 0.01) plasma high-density lipoprotein (HDL). Hens offered 50 and 100 ppm L-carnitine irrespective of application mode also showed reduced (p < 0.01) egg-yolk TC concentration at 32 weeks of age. Dietary supplementation of 50 ppm L-carnitine for breeder turkeys recorded the lowest (p < 0.01) egg-yolk triglyceride (TG) at 40 weeks of age. Hens offered 50 ppm L-carnitine irrespective of application mode recorded the highest (p < 0.05) hen-day egg production. Incidence of dead-in-shell also reduced (p < 0.05) with increasing dosage of L-carnitine. Dietary supplementation of 50 ppm and oral application in drinking water of 100 ppm L-carnitine for breeder turkeys resulted in highest (p < 0.05) egg fertility. Offsprings from breeder hens fed diets supplemented with L-carnitine recorded no post-hatch mortality. Highest (p < 0.05) post-hatch final live weight and weight gain was obtained with poults obtained from hens fed diet supplemented with 50 ppm L-carnitine. In conclusion, dietary supplementation of 50 ppm L-carnitine for turkey hens showed improved serum lipid profile, egg fertility, reduced dead-in-shell, egg-yolk cholesterol and resulted in improved post-hatch growth performance.

Reproductive biology of the great capricorn beetle, Cerambyx cerdo (Coleoptera: Cerambycidae): a protected but occasionally harmful species.

PubMed

Torres-Vila, L M

2017-12-01

Cerambyx cerdo (Cc) is a protected saproxylic beetle in Europe, although it is increasingly reported as an oak 'pest'. Cc ecological features are relatively well known, but, its reproductive biology is still poorly understood. Hence, we investigated the reproductive traits of Cc under laboratory conditions. In females, body length was 44.1 ± 0.9 mm, 28-53 (mean ± SE, range); fecundity 143 ± 11 eggs, 33-347; fertility 78 ± 1%, 65-93; oviposition period 44 ± 3 days, 13-128 and longevity 59 ± 5 days, 16-157. Fecundity was positively correlated with female size, longevity and oviposition period. Daily fecundity was 3.5 ± 0.2 eggs/day, 0.9-6.5 showing a fluctuating synovigenic pattern with a slight decreasing trend over time. Egg length was 3.74 ± 0.01 mm, 2.3-6.0 and egg volume 5.45 ± 0.04 mm3, 2.4-9.6. Egg size was correlated with female size, but, the relative size of eggs was larger in smaller females. Incubation time was 13.5 ± 0.1 days, 7-28. Hatching was superior in larger eggs and neonate size was positively correlated to egg volume. Females were polyandrous (up to 19 matings), but, multiple mating did not enhance fecundity or fertility. In males, body length was 41.8 ± 0.8 mm, 29-53 and longevity 49 ± 3 days, 9-124. Male longevity was unrelated to body size. Males were polygynous (up to 16 matings) and mating number did not affect male longevity. Overall, females were larger and lived longer than males. Cc reproductive traits are compared with those other Cerambycidae, especially with the congeneric pest Cerambyx welensii. Our data may be valuable to improve the protection/management measures of Cc in dehesa woodlands and other oak forests.

Development of space-fertilized eggs and formation of primordial germ cells in the embryos of medaka fish

NASA Astrophysics Data System (ADS)

Ijiri, K.

In the second International Microgravity Laboratory (IML-2) mission in 1994, four small Japanese killifish (Medaka, Oryzias latipes) made a space travel of 15 days aboard a space shuttle. These four adult Medaka fish successfully mated in space for the first time among vertebrate animals. Moreover, the eggs they laid developed normally, at least in their external appearance, hatching as fry (baby fish) in space. Fish mated and laid eggs every day during the first week. Near the end of the mission most of the eggs had a well-developed body with two pigmented eyes. In total, 43 eggs were laid (detected), out of which 8 fry hatched in space, as truly `space-originated' babies. A further 30 fry hatched within 3 days after landing. This is the normal hatching rate, compared with the ground-based data. Among the 8 space-originated fry, four were killed for histological sections, and germ cells at the gonadal region were counted for each fry. Their numbers were in the range of the germ cells of the normal control fry (ground-kept samples). Thus, as embryos developed normally in their external appearance, inside the embryos the formation of primordial germ cells took place normally in space, and their migration to the genital ridges was not hindered by microgravity. The two of the remaining space-originated fry have grown up and been creating their offspring in the laboratory. This proved that the primordial germ cells formed in space were also normal from a functional point of view. The four space-travelled adult fish re-started mating and laying eggs on the 7th day after landing and continued to do so every day afterward. Fertilization rate and hatchability of these eggs were as high as the eggs laid by the laboratory-kept fish. This fact implies that in gametogenesis of adult fish, there are no specific stages of germ cells extremely susceptible to microgravity.

A novel reproductive mode in frogs: a new species of fanged frog with internal fertilization and birth of tadpoles.

PubMed

Iskandar, Djoko T; Evans, Ben J; McGuire, Jimmy A

2014-01-01

We describe a new species of fanged frog (Limnonectes larvaepartus) that is unique among anurans in having both internal fertilization and birth of tadpoles. The new species is endemic to Sulawesi Island, Indonesia. This is the fourth valid species of Limnonectes described from Sulawesi despite that the radiation includes at least 15 species and possibly many more. Fewer than a dozen of the 6455 species of frogs in the world are known to have internal fertilization, and of these, all but the new species either deposit fertilized eggs or give birth to froglets.

Human Cloning

DTIC Science & Technology

2006-07-20

parthenogenesis , to produce human embryos. ACT researchers obtained eggs from seven women, ages 24 to 32, who were paid $3,000 to $5,000. In the SCNT...cumulus cell nucleus began to divide but division stopped at the four-to-six-cell stage. In parthenogenesis , an egg cell is treated with chemicals...Human Subject Protection regulations] as of the date of enactment of this Act, that is derived by fertilization, parthenogenesis , cloning, or any

Amphibian Development in the Virtual Absence of Gravity

NASA Technical Reports Server (NTRS)

Souza, Kenneth A.; Black, Steven D.; Wassersug, Richard J.

1995-01-01

To test whether gravity is required for normal amphibian development, Xenopus laevis females were induced to ovulate aboard the orbiting Space Shuttle. Eggs were fertilized in vitro, and although early embryonic stages showed some abnormalities, the embryos were able to regulate and produce nearly normal larvae. These results demonstrate that a vertebrate can ovulate in the virtual absence of gravity and that the eggs can develop to a free-living stage.

Laboratory observation on spawning, fecundity and larval development of amphioxus ( Branchiostoma belcheri Tsingtaunese)

NASA Astrophysics Data System (ADS)

Wu, Xian-Han; Zhang, Shi-Cui; Wang, Yong-Yuan; Zhang, Bao-Lu; Qu, Yan-Mei; Jiang, Xin-Ji

1994-12-01

Although amphioxus is widespread in temperate and tropical seas, its population is diminishing because of environmental pollution. To keep the population of this evolutionarily important animal from diminishing, study on its reproduction and development is necessary. The main findings in this study on the spawning and fecundity of the amphioxus reared in laboratory and its larval development are as follows. 1. Water temperature markedly affected the spawning. It spawned only when water temperature reached 21°C. 2. Spawning of the amphioxus in laboratory was markedly extended. Initially, the amphioxus spawned at about 7:00 PM, but spawning time was postponed as spawning days went on. 3. The number of eggs produced by a female ranged from 1400 to 12800, average of 5800. This also represents the fecundity of the amphioxus because it shedded all eggs within the ovary at a time. 4. During the first few months of life of the amphioxus, its growth rate changed seasonally. The growth rate in summer and fall was greater than that in winter. 5. The pelagic larva became a benthic adult after 50 days. 6. The amphioxus reared in laboratory from fertilized eggs could produce fertile eggs and sperms. These findings can be a foundation for measures to address the problem of diminishing amphioxus population.

Mechanical stimulation by osmotic and hydrostatic pressure activates Drosophila oocytes in vitro in a calcium-dependent manner

PubMed Central

Horner, Vanessa L.; Wolfner, Mariana F.

2008-01-01

Summary Embryogenesis in vertebrates and marine invertebrates begins when a mature oocyte is fertilized, resulting in a rise in intracellular calcium (Ca2+) that activates development. Insect eggs activate without fertilization via an unknown signal imparted to the egg during ovulation or egg laying. One hypothesis for the activating signal is that deformation of eggs as they pass through a tight orifice provides a mechanical stimulus to trigger activation. Ovulation could produce two forms of mechanical stimulus: external pressure resulting from the passage of oocytes from the ovary into the narrow oviducts, and osmotic pressure caused by hydration-induced swelling of the oocyte within the oviducts. Ovulation could also trigger activation by placing the oocyte in a new environment that contains an activating substance, such as a particular ion. Here, we provide the first evidence that Drosophila oocytes require Ca2+ for activation, and that activation can be triggered in vitro by mechanical stimuli, specifically osmotic and hydrostatic pressure. Our results suggest that activation in Drosophila is triggered by a mechanosensitive process that allows external Ca2+ to enter the oocyte and drive the events of activation. This will allow exploitation of Drosophila genetics to dissect molecular pathways involving Ca2+ and the activation of development. PMID:18304524

'Banking time': egg freezing and the negotiation of future fertility.

PubMed

Waldby, Catherine

2015-01-01

This paper examines the relatively recent practice of non-medical egg freezing, in which women bank their eggs for later use in conceiving a child. Non-medical egg freezing has only been available for about the last five years, as new vitrification techniques have made the success rates for actual conception more reliable than the earlier method of slow freezing. I draw on interviews with both clinicians and women who have banked their eggs to consider how this novel practice articulates with broader issues about the relationship between sexuality, reproduction and the political economy of household formation. Non-medical egg-freezing provides a technical solution to a number of different problems women face with regard to the elongation of the life course, the extension of education, the cost of household establishment and the iterative nature of relationship formation, thematised by the ubiquity of internet dating among the interviewees. I focus on the ways women used egg freezing to manage and reconcile different forms of time.

Revisiting "The Fertilization Fairytale:" An Analysis of Gendered Language Used to Describe Fertilization in Science Textbooks from Middle School to Medical School

ERIC Educational Resources Information Center

Campo-Engelstein, Lisa; Johnson, Nadia L.

2014-01-01

Emily Martin's ("Signs J Women Cult Soc" 16(31):485-501, 1991) article, "The Egg and the Sperm: How Science Has Constructed a Romance Based on Stereotypical Male-Female Roles," was published in "Signs" over 20 years ago. In this groundbreaking article, she discusses how gender roles are often projected onto…

Ectopic Pregnancy

MedlinePlus

... woman is pregnant. If you have an ectopic pregnancy, the fertilized egg grows in the wrong place, ... tubes. The result is usually a miscarriage. Ectopic pregnancy can be a medical emergency if it ruptures. ...

Viscous forces are predominant in the zona pellucida mechanical resistance

NASA Astrophysics Data System (ADS)

Papi, Massimiliano; Maiorana, Alessandro; Douet, Cécile; Maulucci, Giuseppe; Parasassi, Tiziana; Brunelli, Roberto; Goudet, Ghylène; De Spirito, Marco

2013-01-01

The zona pellucida (ZP) is a multilayer glycoprotein spherical shell surrounding mammalian eggs. The ZP's mechanical response plays a crucial role in mammalian fertilization and is a parameter commonly adopted in "in vitro fertilization" to characterize the oocytes quality. While it is assumed that ZP mechanical response is purely elastic, here we prove that dissipative forces cannot be neglected. Physiologically, this evidence implies that an increase in the spermatozoa motility can induce dramatic changes on the ZP reaction force turning ZP shell in an impenetrable barrier leading to fertility impairments.

Age-associated increase in aneuploidy and changes in gene expression in mouse eggs

PubMed Central

Pan, Hua; Ma, Pengpeng; Zhu, Wenting; Schultz, Richard M.

2008-01-01

An increase in the incidence of aneuploidy is well documented with increasing maternal age, in particular in human females. Remarkably, little is known regarding the underlying molecular basis for the age-associated increase in aneuploidy, which is a major source of decreased fertility in humans. Using mouse as a model system we find that eggs obtained from old mice (60–70 weeks of age) display a six-fold increase in the incidence of hyperploidy as assessed by chromosome spreads. Expression profiling of transcripts in oocytes and eggs obtained from young and old mice reveals that ~5% of the transcripts are differentially expressed in oocytes obtained from old females when compared to oocytes obtained from young females (6–12 weeks of age) and that this fraction increases to ~33% in eggs. The latter finding indicates that the normal pattern of degradation of maternal mRNAs that occurs during oocyte maturation is dramatically altered in eggs obtained from old mice and could therefore be a contributing source to the decline in fertility. Analysis of the differentially expressed transcripts also indicated that the strength of the spindle assembly checkpoint is weakened and that higher errors of microtubule-kinetochore interactions constitute part of molecular basis for the ageassociated increase in aneuploidy in females. Last, BRCA1 expression is reduced in oocytes obtained from old females and RNAi-mediated reduction of BRCA1 in oocytes obtained from young females results in perturbing spindle formation and chromosome congression following maturation. PMID:18342300

Effect of climate region and stocking density on ostrich (Struthio camelus) productive performances.

PubMed

Bouyeh, M; Seidavi, A; Mohammadi, H; Sahoo, A; Laudadio, V; Tufarelli, V

2017-02-01

The effects of three climates (hot and dry, mild and humid and Alpine) and three flock densities (<100, 100-300 and >300 m 2 ) on ostrich reproductive and productive traits were studied. Data were compared with the benchmark target sets by the World Ostrich Association (Ostrich benchmark Performance Targets. Version 2, May, 2008) for reproductive qualifications of ostrich. No significant difference was observed on egg production, weight, fertility, hatchability and day-old chicks weight among the three climate conditions; however, the Alpine climate had a lower performance trend. Mild and humid climates had a significant effect of age at sexual maturity for both males and females as well as on the duration of egg production season. Stocking density did not show significant difference on egg production, hatchability, age of male and female at sexual maturity and on duration of egg production season, while an area >300 m 2 showed a reduction in egg weight and day-old chick weight. Further, an area <100 m 2 led to a weaker ostrich fertility rate. Results showed that the ostrich would have a better performance under hot and dry and mild and humid climates as compared to Alpine climate with a stocking density of 100-300 m 2 area per breeder bird. Thus, climatic intervention strategies at Alpine regions may be carried out for maintaining optimal reproductive qualification of ostrich so as to improve the productivity in this sector. © 2016 Blackwell Verlag GmbH.

Standardization of a Patella spp. (Mollusca, Gastropoda) embryo-larval bioassay and advantages of its use in marine ecotoxicology.

PubMed

Pérez, Sara; Fernández, Nuria; Ribeiro, Pedro A

2016-05-01

The use of three limpet species, Patella vulgata Linnaeus, 1758, Patella depressa Pennant, 1777 and Patella ulyssiponensis Gmelin, 1791 as model organisms in marine ecotoxicology has been evaluated. Initial laboratory experiments were aimed to standardize a biological test with embryos and larvae of Patella spp, establishing the percentage of normal trochophore larvae as endpoint. Before conducting in vitro fertilization, oocytes must be maturated artificially by incubation in an alkaline solution; therefore, alkalinizing agent, pH and time of eggs alkalinization were evaluated. Moreover, time of sperm activation, optimum sperm and oocytes concentration during fertilization, gamete contact time, use of stirring during the fertilization, egg concentration and incubation temperature were examined. Minimum sample size per treatment was also estimated. Exposure of oocytes for 10min to FSW alkalinized with NH4OH at pH 9.0, the use of undiluted sperm pre-activated during 45min and a concentration of 200 oocytesmL(-1), a gamete-contact time of 180min and egg incubation at 18°C during 24h at a concentration of 80 eggsmL(-1) were the conditions allowing maximal embryo-larval development success. With an error of 0.05, a sampling size ≥320 allows a 95% confidence in the estimate. This Patella spp. acute bioassay fulfills a number of important a priori requirements to be used in ecotoxicological studies. Nevertheless, in vitro fertilization requires considerable handling, which may lead to failure in fecundation. Such difficulties are also addressed, in order to facilitate the routine use of this protocol by other laboratories. Copyright © 2016 Elsevier Inc. All rights reserved.

Rediscovering sperm ion channels with the patch-clamp technique

PubMed Central

Kirichok, Yuriy; Lishko, Polina V.

2011-01-01

Upon ejaculation, mammalian spermatozoa have to undergo a sequence of physiological transformations within the female reproductive tract that will allow them to reach and fertilize the egg. These include initiation of motility, hyperactivation of motility and perhaps chemotaxis toward the egg, and culminate in the acrosome reaction that permits sperm to penetrate the protective vestments of the egg. These physiological responses are triggered through the activation of sperm ion channels that cause elevations of sperm intracellular pH and Ca2+ in response to certain cues within the female reproductive tract. Despite their key role in sperm physiology and their absolute requirement for the process of fertilization, sperm ion channels remain poorly understood due to the extreme difficulty in application of the patch-clamp technique to spermatozoa. This review covers the topic of sperm ion channels in the following order: first, we discuss how the intracellular Ca2+ and pH signaling mediated by sperm ion channels controls sperm behavior during the process of fertilization. Then, we briefly cover the history of the methodology to study sperm ion channels, which culminated in the recent development of a reproducible whole-cell patch-clamp technique for mouse and human cells. We further discuss the main approaches used to patch-clamp mature mouse and human spermatozoa. Finally, we focus on the newly discovered sperm ion channels CatSper, KSper (Slo3) and HSper (Hv1), identified by the sperm patch-clamp technique. We conclude that the patch-clamp technique has markedly improved and shifted our understanding of the sperm ion channels, in addition to revealing significant species-specific differences in these channels. This method is critical for identification of the molecular mechanisms that control sperm behavior within the female reproductive tract and make fertilization possible. PMID:21642646

Effects of prolonged exposure to perchlorate on thyroid and reproductive function in zebrafish

USGS Publications Warehouse

Mukhi, S.; Patino, R.

2007-01-01

The objectives of this study were to determine the effects of prolonged exposure to perchlorate on (1) thyroid status and reproductive performance of adult zebrafish (Danio rerio) and (2) F1 embryo survival and early larval development. Using a static-renewal procedure, mixed sex populations of adult zebrafish were exposed to 0, 10, and 100 mg/l nominal concentrations of waterborne perchlorate for 10 weeks. Thyroid histology was qualitatively assessed, and females and males were separated and further exposed to their respective treatments for six additional weeks. Eight females in each tank replicate (n = 3) were paired weekly with four males from the same respective treatment, and packed-egg (spawn) volume (PEV) was measured each of the last five weeks. At least once during weeks 14-16 of exposure, other end points measured included fertilization rate, fertilized egg diameter, hatching rate, standard length, and craniofacial development of 4-day-postfertilization larvae and thyroid hormone content of 3.5-h embryos and of exposed mothers. At 10 weeks of exposure, perchlorate at both concentrations caused thyroidal hypertrophy and colloid depletion. A marked reduction in PEV was observed toward the end of the 6-week spawning period, but fertilization and embryo hatching rates were unaffected. Fertilized egg diameter and larval length were increased by parental exposure to perchlorate. Larval head depth was unaffected but the forward protrusion of the lower jaw-associated cartilage complexes, Meckel's and ceratohyal, was decreased. Exposure to both concentrations of perchlorate inhibited whole-body thyroxine content in mothers and embryos, but triiodothyronine content was unchanged. In conclusion, prolonged exposure of adult zebrafish to perchlorate not only disrupts their thyroid endocrine system but also impairs reproduction and influences early F1 development. ?? 2007 Oxford University Press.

Genetic-economic evaluation of traits in a goose meat enterprise.

PubMed

Shalev, B A; Pasternak, H

1999-05-01

1. Goose can be considered as an additional and inexpensive meat source, provided that the marketing age does not exceed 8 weeks. Using the ability of geese to eat grass may reduce the intake of concentrated food up to 30%. 2. According to an equation developed, growth rate accounts for about 58% of the annual breeding gains, egg number 28%, feather yield 10%, fertility and mortality about 2%. These values are about the same for a wide range of food prices. 3. Employing realistic values for expected annual genetic gains reveals that the customary practice of keeping breeders for 5 to 6 years should be replaced by a much shorter cycle of 3 years because the economic gain from the shorter generation interval of selection exceeds the replacement costs.

Sexy males and sexless females: the origin of triploid apomicts.

PubMed

Muralidhar, P; Haig, D

2017-05-01

Apomixis and polyploidy are closely associated in angiosperms, but the evolutionary reason for this association is unknown. Taraxacum officinale, the common dandelion, exists both as diploid sexuals and triploid apomicts. Here, in the context of T. officinale, we provide a model of the evolution of triploid apomicts from diploid sexuals. We posit an apomictic allele that arrests female meiosis in diploids, so that the plant produces diploid egg cells that can develop without fertilization, but haploid pollen. We propose occasional fertilization of diploid egg cells by haploid pollen, resulting in triploid apomicts that produce triploid egg cells but largely nonfunctional pollen. The irreversibility of this process renders diploid partial apomicts evolutionarily short-lived, and results in fixation of triploid apomicts except when they suffer extreme selective disadvantages. Our model can account for the high genetic diversity found in T. officinale triploid populations, because recombinant haploid pollen produced by diploids allows the apomictic allele to spread onto many genetic backgrounds. This leads to multiple clonal lineages in the newly apomictic population, and thereby alleviates some of the usual pitfalls of asexual reproduction.

Calcium signaling in mammalian egg activation and embryo development: Influence of subcellular localization

PubMed Central

Miao, Yi-Liang; Williams, Carmen J.

2012-01-01

Calcium (Ca2+) signals drive the fundamental events surrounding fertilization and the activation of development in all species examined to date. Initial studies of Ca2+ signaling at fertilization in marine animals were tightly linked to new discoveries of bioluminescent proteins and their use as fluorescent Ca2+ sensors. Since that time, there has been rapid progress in our understanding of the key functions for Ca2+ in many cell types and the impact of cellular localization on Ca2+ signaling pathways. In this review, which focuses on mammalian egg activation, we consider how Ca2+ is regulated and stored at different stages of oocyte development and examine the functions of molecules that serve as both regulators of Ca2+ release and effectors of Ca2+ signals. We then summarize studies exploring how Ca2+ directs downstream effectors mediating both egg activation and later signaling events required for successful preimplantation embryo development. Throughout this review, we focus attention on how localization of Ca2+ signals influences downstream signaling events, and attempt to highlight gaps in our knowledge that are ripe areas for future research. PMID:22888043

Human sperm bind to the N-terminal domain of ZP2 in humanized zonae pellucidae in transgenic mice

PubMed Central

Baibakov, Boris; Boggs, Nathan A.; Yauger, Belinda; Baibakov, Galina

2012-01-01

Fertilization requires taxon-specific gamete recognition, and human sperm do not bind to zonae pellucidae (ZP1–3) surrounding mouse eggs. Using transgenesis to replace endogenous mouse proteins with human homologues, gain-of-function sperm-binding assays were established to evaluate human gamete recognition. Human sperm bound only to zonae pellucidae containing human ZP2, either alone or coexpressed with other human zona proteins. Binding to the humanized matrix was a dominant effect that resulted in human sperm penetration of the zona pellucida and accumulation in the perivitelline space, where they were unable to fuse with mouse eggs. Using recombinant peptides, the site of gamete recognition was located to a defined domain in the N terminus of ZP2. These results provide experimental evidence for the role of ZP2 in mediating sperm binding to the zona pellucida and support a model in which human sperm–egg recognition is dependent on an N-terminal domain of ZP2, which is degraded after fertilization to provide a definitive block to polyspermy. PMID:22734000

Oocyte cryopreservation for donor egg banking.

PubMed

Cobo, Ana; Remohí, José; Chang, Ching-Chien; Nagy, Zsolt Peter

2011-09-01

Oocyte donation is an efficient alternative to using own oocytes in IVF treatment for different indications. Unfortunately, 'traditional' (fresh) egg donations are challenged with inefficiency, difficulties of synchronization, very long waiting periods and lack of quarantine measures. Given the recent improvements in the efficiency of oocyte cryopreservation, it is reasonable to examine if egg donation through oocyte cryopreservation has merits. The objective of the current manuscript is to review existing literature on this topic and to report on the most recent outcomes from two established donor cryobank centres. Reports on egg donation using slow freezing are scarce and though results are encouraging, outcomes are not yet comparable to a fresh egg donation treatment. Vitrification on the other hand appears to provide high survival rates (90%) of donor oocytes and comparable fertilization, embryo development, implantation and pregnancy rates to traditional (fresh) egg donation. Besides the excellent outcomes, the ease of use for both donors and recipients, higher efficiency, lower cost and avoiding the problem of synchronization are all features associated with the benefit of a donor egg cryobank and makes it likely that this approach becomes the future standard of care. Oocyte donation is one of the last resorts in IVF treatment for couples challenged with infertility problems. However, traditional (fresh) egg donation, as it is performed today, is not very efficient, as typically all eggs from one donor are given to only one recipient, it is arduous as it requires an excellent synchronization between the donor and recipient and there are months or years of waiting time. Because of the development of an efficient oocyte cryopreservation technique, it is now possible to cryo-store donor (as well as non-donor) eggs, maintaining their viability and allowing their use whenever there is demand. Therefore, creating a donor oocyte cryobank would carry many advantages. In the present manuscript, the current experience with oocyte donation using cryopreservation technology is reviewed. The outcomes of two recently established donor egg cryobanks at Instituto Valenciano de Infertilidad in Spain and Reproductive Biology Associates in the USA (involving a large number of cases) demonstrate that egg cryo-survival is high and that fertilization, embryo development, implantation and pregnancy rates are similar to those reported after fresh egg donation. It also provides additional advantages of being more efficient, more economical, easier for both donors and recipients and potentially also safer, because eggs can now be quarantined for 6 months (or longer) to retest for infectious diseases in the donors. It is the opinion of the authors, based on several advantages associated with the use of donor egg cryobanking, that in the future there will be fewer traditional egg donations and increasingly more cryo-egg donations. Copyright © 2011 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Variation in embryonic mortality and maternal transcript expression among Atlantic cod (Gadus morhua) broodstock: a functional genomics study.

PubMed

Rise, Matthew L; Nash, Gordon W; Hall, Jennifer R; Booman, Marije; Hori, Tiago S; Trippel, Edward A; Gamperl, A Kurt

2014-12-01

Early life stage mortality is an important issue for Atlantic cod aquaculture, yet the impact of the cod maternal (egg) transcriptome on egg quality and mortality during embryonic development is poorly understood. In the present work, we studied embryonic mortality and maternal transcript expression using eggs from 15 females. Total mortality at 7days post-fertilization (7 dpf, segmentation stage) was used as an indice of egg quality. A 20,000 probe (20K) microarray experiment compared the 7hours post-fertilization (7 hpf, ~2-cell stage) egg transcriptome of the two lowest quality females (>90% mortality at 7 dpf) to that of the highest quality female (~16% mortality at 7 dpf). Forty-three microarray probes were consistently differentially expressed in both low versus high quality egg comparisons (25 higher expressed in low quality eggs, and 18 higher expressed in high quality eggs). The microarray experiment also identified many immune-relevant genes [e.g. interferon (IFN) pathway genes ifngr1 and ifrd1)] that were highly expressed in eggs of all 3 females regardless of quality. Twelve of the 43 candidate egg quality-associated genes, and ifngr1, ifrd1 and irf7, were included in a qPCR study with 7 hpf eggs from all 15 females. Then, the genes that were confirmed by qPCR to be greater than 2-fold differentially expressed between 7 hpf eggs from the lowest and highest quality females (dcbld1, ddc, and acy3 more highly expressed in the 2 lowest quality females; kpna7 and hacd1 more highly expressed in the highest quality female), and the 3 IFN pathway genes, were included in a second qPCR study with unfertilized eggs. While some maternal transcripts included in these qPCR studies were associated with extremes in egg quality, there was little correlation between egg quality and gene expression when all females were considered. Both dcbld1 and ddc showed greater than 100-fold differences in transcript expression between females and were potentially influenced by family. The Atlantic cod ddc (dopa decarboxylase) complete cDNA was characterized, and has a 1461bp open reading frame encoding a 486 amino acid protein that contains all eight residues of the conserved pyridoxal 5'-phosphate binding site including the catalytic lysine. This study provides valuable new information and resources related to the Atlantic cod egg transcriptome. Some of these microarray-identified, qPCR-confirmed, Atlantic cod egg transcripts (e.g. ddc, kpna7) play important roles during embryonic development of other vertebrate species, and may have similar functions in Atlantic cod. Copyright © 2014. Published by Elsevier B.V.

Phospholipase C and D regulation of Src, calcium release and membrane fusion during Xenopus laevis development

PubMed Central

Stith, Bradley J.

2015-01-01

This review emphasizes how lipids regulate membrane fusion and the proteins involved in three developmental stages: oocyte maturation to the fertilizable egg, fertilization and during first cleavage. Decades of work show that phosphatidic acid (PA) releases intracellular calcium, and recent work shows that the lipid can activate Src tyrosine kinase or phospholipase C during Xenopus fertilization. Numerous reports are summarized to show three levels of increase in lipid second messengers inositol 1,4,5-trisphosphate and sn 1,2-diacylglycerol (DAG) during the three different developmental stages. In addition, possible roles for PA, ceramide, lysophosphatidylcholine, plasmalogens, phosphatidylinositol 4-phosphate, phosphatidylinositol 5-phosphate, phosphatidylinositol 4,5-bisphosphate, membrane microdomains (rafts) and phosphatidylinositol 3,4,5-trisphosphate in regulation of membrane fusion (acrosome reaction, sperm-egg fusion, cortical granule exocytosis), inositol 1,4,5-trisphosphate receptors, and calcium release are discussed. The role of six lipases involved in generating putative lipid second messengers during fertilization is also discussed: phospholipase D, autotaxin, lipin1, sphingomyelinase, phospholipase C, and phospholipase A2. More specifically, proteins involved in developmental events and their regulation through lipid binding to SH3, SH4, PH, PX, or C2 protein domains is emphasized. New models are presented for PA activation of Src (through SH3, SH4 and a unique domain), that this may be why the SH2 domain of PLCγ is not required for Xenopus fertilization, PA activation of phospholipase C, a role for PA during the calcium wave after fertilization, and that calcium/calmodulin may be responsible for the loss of Src from rafts after fertilization. Also discussed is that the large DAG increase during fertilization derives from phospholipase D production of PA and lipin dephosphorylation to DAG. PMID:25748412