scholarly journals In Vivo Analysis of Embryo Development and Behavioral Response of Medaka Fish under Static Magnetic Field Exposures

Author(s):  
Weinong Sun ◽  
Yaqing He ◽  
Sai-Wing Leung ◽  
Yuen-Chong Kong

The static magnetic field (SMF) in human exposure has become a health risk concern, especially with respect to prolonged exposure. The International Commission on Non-Ionizing Radiation Protection (ICNIRP) has been considering cell or animal models to be adopted to estimate the possible human health impacts after such exposure. The medaka fish is a good animal model for human-related health assessment studies; this paper examines both the embryo development and behavioral responses in medaka fish in vivo to long-term SMF exposure at the mT level. SMF exposure was examined for the complete developmental period of embryos until hatched; the embryos were monitored and recorded every 24 h for different morphological abnormalities in their developmental stages. The behavioral response of adult fish was also examined by analyzing their swimming velocities and positioning as compared with that of the control group. It was observed that there were no impacts on embryo development under prolonged exposure up to about 100 mT while the swimming behavior of the adult fish under exposure was different to the control group—the swimming movement of the treated group was more static, with an average velocity of 24.6% less as observed over a 24-h duration.

1984 ◽  
Vol 3 (1) ◽  
pp. 223-234
Author(s):  
Frank Papatheofanis ◽  
Bill Fapatheofanls ◽  
Robert Ray

2016 ◽  
Vol 28 (2) ◽  
pp. 210
Author(s):  
P. Hugon ◽  
J. Lamy ◽  
E. Corbin ◽  
P. Mermillod ◽  
M. Saint-Dizier

This study was designed to evaluate the effects of oviductal fluid at different periovulatory times on oocyte maturation, modification of the zona pellucida (ZP), fertilization and embryo development. Bovine oviducts were collected at a slaughterhouse and classified as preovulatory (pre-ov: 1 pre-ov follicle and a regressing corpus luteum) or post-ovulatory (post-ov: a corpus haemorrhagicum or recent corpus luteum; n = 10 cows/stage). Both oviducts were flushed with 1 mL of sterile TCM-199, and oviductal flushes (OF) were aliquoted and stored at –80°C. Abattoir-derived bovine ovaries were aspirated and cumulus‐oocyte complexes (COC) with at least 3 cumulus layers and homogeneous oocyte cytoplasm were in vitro matured for 22 h in standard maturation medium (control group, n = 319) or in standard medium with 2× concentrated additives supplemented (50% v/v) with pre-ov OF (n = 255) or post-ov OF (n = 248). After in vitro maturation (IVM), subgroups of COC were denuded, and the time of digestion of the ZP by pronase 0.1% (v/v in TCM-199) was determined to evaluate ZP hardening. After IVM, COC were fertilised in vitro for 18–20 h at a final concentration of 1.106 million spermatozoa (spz)/mL. After in vitro fertilization (IVF), COC were denuded, washed twice and cultured for 8 days more under standard conditions. After IVM, IVF, and embryo culture, oocytes/embryos were fixed with ethanol, stained with Hoescht, and examined under fluorescence microscopy for determination of (1) maturation and developmental stages, (2) numbers of fertilised and polyspermic oocytes, and (3) spz bound to the ZP. Percentages were compared between groups by chi-square. Times of ZP digestion were compared by Kruskal‐Wallis test. Numbers of spz bound to the ZP were compared by ANOVA on normalised data followed by Newman-Keuls tests. Data are presented as mean ± SEM. A P < 0.05 was considered significant. Addition of OF during IVM had no effect on maturation rates compared with the control. However, the digestion time of the ZP by pronase was reduced after IVM with pre-ov OF (313 ± 21 s; n = 26) compared with post-ov OF (459 ± 23 s; n = 23) but not with the control (416 ± 30 s; n = 25). After IVF, the number of spermatozoa bound to the ZP was increased after IVM with pre-ov OF (57 ± 5 spz/oocyte; n = 67) and decreased after IVM with post-ov OF (34 ± 3 spz/oocyte; n = 76) compared with the control (42 ± 5 spz/oocyte; n = 60). Addition of OF during IVM had no effect on rates of IVF and polyspermia. However, the rate of development to the blastocyst stage was less after IVM with post-ov OF (10%, n = 97 cleaved oocytes) compared with control (24%, n = 130) and pre-ov OF (29%, n = 101). In conclusion, the OF collected before ovulation decreased the resistance of the ZP to protease digestion and increased its ability to bind spz, whereas it was the opposite for the post-ov OF. Furthermore, the post-ov OF decreased the developmental competence of fertilised oocytes.


2009 ◽  
Vol 21 (1) ◽  
pp. 104
Author(s):  
J. T. Aaltonen ◽  
K. J. Mattson ◽  
N. M. Loskutoff

As described in the IETS Manual (Stringfellow and Seidel, 1995), and endorsed by the OIE, trypsin can be used (for specific pathogens and livestock) to effectively remove certain infectious agents from in vivo-derived embryos for international transport. Because of the multimillion-dollar AI industry for livestock, the OIE has encouraged more research in developing similar decontamination techniques for semen as an added safeguard to animal quarantine for the prevention of disease transmission. Most or all of the earlier studies on embryos used a porcine pancreatic-derived trypsin. Because of more stringent guidelines from international regulatory agencies on the use of animal products, several serine protease recombinants are now available. Previous experiments comparing the porcine pancreatic extract with a recombinant bovine sequence trypsin developed in corn resulted in no statistical difference in cleavage or morula/blastocyst rates. (Mattson et al. 2008 Theriogenology 69, 724–727). An additional in vivo study treating bovine sperm with a yeast-derived human-sequence trypsin resulted in significantly more transferable-quality embryos after the AI of superovulated cows as compared with sperm not treated with trypsin (Blevins et al. 2008 Reprod. Fertil. Dev. 20, 84). The goal of this experiment was to examine the in vitro development of bovine embryos produced from sperm treated with a recombinant trypsin found in a commercially available density gradient centrifugation (DGC) product (Bovipure, Nidacon, Sweden) compared with DGC without trypsin. Oocyte aspiration, maturation, fertilization, and embryo culture were performed using standard methods in 5 replications (n = 2220 oocytes). Semen was collected and pooled from 2 Bos taurus bulls and frozen in an egg-yolk cryodiluent (Biladyl, Minitube). The semen was processed using Bovipure DGC composed of 2 mL of 40% colloid of silane-coated silica particles containing either a yeast-derived human sequence recombinant trypsin containing no animal by-products (n = 1126 oocytes) or the same colloid without trypsin as the control group (n = 1094 oocytes). Both 40% concentrations were layered over 2 mL of an 80% concentration of the same colloid without any additives. The density gradients were centrifuged at 300g for 20 min, after which time the pellets were washed in 5 mL of prewarmed TL Hepes solution (Cambrex) and centrifuged at 500g for 10 min. The resulting sperm pellets were then resuspended in a volume calculated to provide 1 × 106 sperm mL–1, to be used for in vitro inseminations. Results were compared using a 2-tailed unpaired t-test. Cleavage rates for the trypsin-treated sperm (n = 969, 35.8%) and the control (n = 950, 44.3%) groups were not statistically different (P = 0.20). Although more embryos reached the morula to blastocyst stages in the control group (n = 421, 61.0%) than in the trypsinized group (n = 347, 54.7%), these differences also were not statistically significant (P = 0.85). In conclusion, trypsinized Bovipure DGC of sperm before insemination showed no detrimental effects on IVF-derived bovine embryo development.


2013 ◽  
Vol 47 (3) ◽  
pp. 179-187 ◽  
Author(s):  
V. F. Chekhun ◽  
Yu. V. Lozovskaya ◽  
N. Yu. Lukyanova ◽  
D. V. Demash ◽  
I. N. Todor ◽  
...  

2014 ◽  
Vol 26 (1) ◽  
pp. 128
Author(s):  
C. P. Buemo ◽  
A. Gambini ◽  
I. Hiriart ◽  
D. Salamone

Somatic cell nuclear transfer (SCNT) derived blastocysts have lower cell number than IVF-derived blastocysts and their in vivo counterparts. The aim of this study was to improve the blastocyst rates and quality of SCNT blastocysts by the aggregation of genetically identical free zona pellucida (ZP) porcine clones. Cumulus–oocyte complexes were recovered from slaughterhouse ovaries by follicular aspiration. Maturation was performed in TCM for 42 to 48 h at 39°C and 5% CO2. After denudation by treatment with hyaluronidase, mature oocytes were stripped of the ZP using a protease and then enucleated by micromanipulation; staining was performed with Hoechst 33342 to observe metaphase II. Ooplasms were placed in phytohemagglutinin to permit different membranes to adhere between each other; the ooplasm membrane was adhered to a porcine fetal fibroblast from an in vitro culture. Adhered membranes of the donor cell nucleus and enucleated oocyte cytoplasm were electrofused through the use of an electric pulse (80 V for 30 μs). All reconstituted embryos (RE) were electrically activated using an electroporator in activation medium (0.3 M mannitol, 1.0 mM CaCl2, 0.1 mM MgCl2, and 0.01% PVA) by a DC pulse of 1.2 kV cm–1 for 80 μs. Then, the oocytes were incubated in 2 mM 6-DMAP for 3 h. In vitro culture of free ZP embryos was achieved in a system of well of wells in 100 μL of medium, placing 3 activated oocytes per microwell (aggregation embryo), whereas the control group was cultivated with equal drops without microwells. Embryos were cultivated at 39°C in 5% O2, 5% CO2 for 7 days in SOF medium with a supplement of 10% fetal bovine serum on the fifth day. The RE were placed in microwells. Two experimental groups were used, control group (not added 1X) and 3 RE per microwell (3X). At Day 7, resulting blastocysts were classified according to their morphology and diameter to determine their quality and evaluate if the embryo aggregation improves it. Results demonstrated that aggregation improves in vitro embryo development rates until blastocyst stage and indicated that blastocysts rates calculated over total number of oocytes do not differ between groups (Table 1). Embryo aggregation improves cleavage per oocyte and cleavage per microwell rates, presenting statistical significant differences and increasing the probabilities of higher embryo development generation until the blastocyst stage with better quality and higher diameter. Table 1.Somatic cell nuclear transfer cloning and embryo aggregation


2009 ◽  
Vol 21 (1) ◽  
pp. 200
Author(s):  
M. Clemente ◽  
A. T. Palasz ◽  
J. de La Fuente ◽  
P. Lonergan ◽  
A. Gutierrez-Adan ◽  
...  

Hyaluronan (HA), which progressively increases during embryogenesis, is a glycosaminoglycan that plays a major role in oocyte/embryo development (Fenderson et al. 1993 Differentiation 54, 85–95). One of the main functions of HA is to participate in the cell proliferation and migration that are controlled by HA receptors, RHAMM and C44, and by the presence of different HA synthases, Has1, Has2, and Has3. All have very distinctive features and functions at different stages of embryo development. The objective of this study was to determine the relative mRNA abundance of HA receptors and synthases in Day 7 and 13 bovine embryos derived in vitro or in vivo. In vitro embryos were produced by standard oocyte maturation and fertilization procedures. Presumptive zygotes were cultured in groups of 25 in 25-μL droplets of synthetic oviduct fluid supplemented with 5% FCS at 39°C, 5% CO2, and 5%O2 with maximum humidity. In vivo blastocysts were collected from superovulated heifers on Day 7 (estrus = Day 0) by uterine flushing and on Day 13 immediately after slaughter by flushing the dissected reproductive tracts. All embryos were frozen in LN2 and stored at –80°C for mRNA extraction. Quantification of transcripts for RHAMM and CD44 receptors and Has2 and Has3 synthases was performed on groups of ten Day 7 blastocysts (3 groups for in vivo or in vitro) and individual Day 13 embryos (7 embryos in vivo or in vitro) by real-time quantitative RT-PCR. Data on differences in transcript abundance were analyzed by ANOVA. The relative abundance of the Has2 and Has3 synthases was similar between in vivo and in vitro embryos, irrespective of their developmental stage. The quantity of CD44 was significantly higher in in vitro compared with in vivo embryos only on Day 7. However, the quantity of RHAMM receptor was higher on Day 13 in in vitro compared with in vivo embryos. When the comparison was done between developmental stages (Day 7 v. Day 13) for in vivo and in vitro embryos, we found that in vivo-produced Day 7 blastocysts expressed significantly more RHAMM receptor than embryos on Day 13. The reverse pattern of expression was shown for CD44 receptor. For in vitro embryos, the only difference observed was for Has3, which was up-regulated on Day 13 compared with Day 7 embryos. In conclusion, the present study demonstrates, for the first time, developmental changes in the abundance of RHAMM and CD44 receptor mRNA and Has2 and Has3 synthase mRNA in in vivo and in vitro bovine-derived embryos on Day 7 and 13. We believe that our results will provide new insight into the potential role of this intriguing multifunctional molecule in bovine early embryo development.


2015 ◽  
Vol 27 (1) ◽  
pp. 161
Author(s):  
A. E. Velásquez ◽  
D. Veraguas ◽  
J. F. Cox ◽  
F. O. Castro ◽  
L. l. Rodriguez

Embryo splitting has been used since the early 1980s to produce identical twins and increase the pregnancy rate per available embryo. However, very little is known about the effect of splitting on embryo development and competence. Indeed splitting could provoke a negative effect on embryo survival and it can be presumed that each demi-embryo might respond differently to the injury. In this sense, even when embryos are genetically and morphologically identical at the moment of splitting, their developmental potential and molecular characteristics might change as a consequence of the intense manipulation or epigenetic differences due to the interaction with the environment. We have proposed an approach to evaluate the effect of blastocyst splitting on the morphological and gene expression in in vivo development up to the filamentous stage. For that, the effect of splitting on bovine embryo development was evaluated during the elongation period by transferring split and nonsplit IVF-derived blastocysts to cattle recipients and collecting them at Day 17 of development. The number of collected embryos, embryo size, and global gene expression was compared between both groups. Collected elongated embryos derived from split blastocyst were compared with time matched collected control embryos. From 14 transferred hemi-embryos, 5 (35.7%) were collected while 9 elongated from 17 controls were recovered (52.9%). Neither the recovery rate nor the average length of the elongated embryos was significantly different between the two treatments. However, when embryos were rated depending on their size, more than 50% of embryos from the control group had a length surpassing 100 mm, while only 33% of the split embryos reached that size. Global gene expression was performed using 2-colour microarray-based gene expression analysis. This was a whole-genome microarray study comparing 10 individual elongated embryos derived from split and nonsplit IVF blastocysts. Genes were considered differentially expressed if the fold change is greater than 2 (up or down-regulation) with P ≤ 0.05. A total of 29 585 transcripts were detected in all embryos. From those, 449 (1.5%) were differentially expressed between elongated embryos derived from split and nonsplit IVF blastocysts, among them, 248 (0.83%) genes were down-regulated and 201 (0.67%) genes were up-regulated in split embryos. Gene ontology analysis identified deregulated genes related with intrinsic component of membrane (ELOVL7, GJA1, LAPTM4B, LDLR, SLC18A2, SLC1A3, SLC38A5, TSPAN13), lipid transporter activity (RBP4, APOA1, MTTP), and organophosphate ester transport (GJA1, GJB1, ATP9B). In conclusion, we showed that splitting affect the in vivo developmental capability and gene expression profile during the elongation period of bovine embryos. However, further studies are needed to determine the long-term effect of this technique to produce viable offspring. This work was partially supported by Fondecyt No. 11100082 and Fondequip No. EQM12113 from the Ministry of Education of Chile.


2008 ◽  
Vol 20 (9) ◽  
pp. 81
Author(s):  
K. H. Beilby ◽  
C. C. Grupen ◽  
W. M. C. Maxwell ◽  
G. Evans

The use of sex-sorted ram sperm results in pregnancy rates similar or superior to that of non-sorted sperm after laparoscopic insemination of synchronised ewes under defined conditions [1, 2]. To further assess the fertility of sex-sorted ram sperm, embryo production and development rates were examined after the insemination of superovulated ewes with either sex-sorted or non-sorted sperm. Merino ewes (n = 30) were synchronised in oestrus using progestagen sponges inserted for 14 days and hormonally stimulated with PMSG (600 IU) on sponge removal (SR), FSH (133 mg) at decreasing doses every 12 h for 4 days before insemination, and GnRH 24 h before insemination. Each ewe was inseminated in the uterus by laparoscopy 42–44 h after SR with 15 × 106 motile X- or Y-chromosome bearing or non-sorted spermatozoa. On day 6 after insemination, antegrade flushing of both uterine horns was performed. Overall, the fertilisation rate was higher using X-chromosome bearing sperm (70%) compared with both Y-chromosome enriched (59%) and non-sorted treatments (64%). Embryo development was more advanced after the insemination of non-sorted sperm with more hatching (hg) and expanded blastocysts (exb) recovered per animal (hg: 3.37 ± 1.19; exb: 5.00 ± 1.68) compared with sorted groups (X hg: 1.71 ± 0.92; exb: 3.28 ± 1.80; Y hg: 1.67 ± 1.67; exb: 1.50 ± 1.02). Moreover, embryos were recovered at earlier developmental stages after insemination with Y- compared with X-chromosome bearing sperm. In conclusion, the use of sex-sorted sperm did not affect the efficiency of embryo production. However, the development of embryos derived from sex-sorted sperm was delayed compared with those from non-sorted sperm. (1) de Graaf et al. 2007. Reproduction in Domestic Animals 42, 648–653 (2) Beilby et al. 2008. Theriogenology [IN PRESS]


Author(s):  
Wanda B. High ◽  
Joseph Sikora ◽  
Kamil Ugurbil ◽  
Michael Garwood

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