scholarly journals Features of the preparation of biological material for genome editing in cattle

2019 ◽  
Vol 191 (12) ◽  
pp. 40-44
Author(s):  
A. Barkova ◽  
M. Modorov ◽  
G. Isaeva ◽  
A. Krivonogova
Keyword(s):  
Genome Editing ◽  
Biological Material ◽  
Genetic Material ◽  
Cumulus Cells ◽  
Vitro Fertilization ◽  
Expected Time ◽  
Donor Material ◽  
Material Transportation

Abstract. To carry out genome editing in cattle, an effective and well-functioning system for obtaining gametes, fertilizing eggs and their cryopreservation is necessary. Aim of the work: review and research of present-day existing methods of obtaining, insemination and cryopreservation of donor material, in order to provide genome editing in cows. Methods and materials. The work is completed according to the theme No. 0532-2019-0001 “Development of complex technology of marker-based genome selection of agricultural animals” within State Order of Ministry of Education and Science of the Russian Federation. The analysis of open scientific literature on the issues of in vitro fertilization in animals, cryopreservation of oocytes and embryons, sperm preparation and methods of insemination of cows’ oocytes, and cryopreservation of oocytes and embryons of animals is done. Features of the preparation of biological material of cattle for genome editing by microinjection into ooplasm are described. Results of research and duscussion. At present time there are two ways to obtain donor material from cattle: from live animals and taking ovaries after slaughtering cows. Material transportation is carried out at a temperature of 30–37 °C depending on the distance to the laboratory and expected time period of transportation. Oocyte-cumulus complexes can be removed by ovarian dissection and aspiration of visible follicles. In both cases, immature eggs are predominantly obtained. Subsequent ripening is carried out in vitro using special media in a CO2 incubator. The culture medium for oocyte maturation should contain hormones that mimic the peak of LH (luteinizing hormone), which occurs in vivo during the maturation of oocytes before ovulation. To accumulate a certain number of eggs at the stage of MII, it is recommended to carry out their cryopreservation by the method of vitrification, having previously released the oocyte from the cumulus cells. After thawing, oocytes need to be incubated for 2–3 hours 38.5 °C in 5–6.5% CO2 to restore the spindle. In order to make editing more effective, the introduction of genetic material is recommended to be carried out in parallel with the fertilization method “icsi”. In humans, mice and rabbits, an injection of sperm into the cytoplasm is sufficient to activate the oocyte, however, in cattle, just micro-injection of the sperm is not enough and often the male pronucleus does not form. To solve the problem, various methods are used, including freezing-thawing of sperm, resulting in damage of a membrane, or addition of heparin-glutathione into the medium that increases decondensation of the sperm DNA.

74 IN VIVO SURVIVAL OF DOMESTIC CAT OOCYTES AFTER VITRIFICATION, INTRACYTOPLASMIC SPERM INJECTION, AND TRANSFER TO RECIPIENTS

2008 ◽  
Vol 20 (1) ◽  
pp. 118 ◽  
Author(s):  
M. C. Gómez ◽  
N. Kagawa ◽  
C. E. Pope ◽  
M. Kuwayama ◽  
S. P. Leibo ◽  
...  
Keyword(s):  
Intracytoplasmic Sperm Injection ◽  
Polar Body ◽  
Oocyte Retrieval ◽  
Cumulus Cells ◽  
Domestic Cat ◽  
Minimal Amount ◽  
Vitro Fertilization ◽  
First Polar Body

The ability to cryopreserve female gametes efficiently holds immense economic and genetic implications. The purpose of the present project was to determine if domestic cat oocytes could be cryopreserved successfully by use of the Cryotop method. We evaluated (a) cleavage frequency after in vitro fertilization (IVF) v. intracytoplasmic sperm injection (ICSI) of in vivo- and in vitro-matured oocytes after vitrification, and (b) fetal development after transfer of resultant embryos into recipients. In vivo-matured cumulus–oocyte complexes (COCs) were recovered from gonadotropin-treated donors at 24 h after LH treatment, denuded of cumulus cells, and examined for the presence of the first polar body (PB). In vitro-matured COCs were obtained from ovaries donated by local clinics and placed into maturation medium for 24 h before cumulus cells were removed and PB status was determined. Oocytes were cryopreserved by the Cryotop method (Kuwayama et al. 2005 Reprod. Biomed. Online 11, 608–614) in a vitrification solution consisting of 15% DMSO, 15% ethylene glycol, and 18% sucrose. For IVF, oocytes were co-incubated with 1 � 106 motile spermatozoa mL–1 in droplets of modified Tyrode's medium in 5% CO2/air at 38�C (Pope et al. 2006 Theriogenology 66, 59–71). For ICSI, an immobilized spermatozoon was loaded into the injection pipette, which was then pushed through the zona pellucida into the ooplasm. After a minimal amount of ooplasm was aspirated into the pipette, the spermatozoon was carefully expelled, along with the aspirated ooplasm. After ICSI, or at 5 or 18 h post-insemination, in vivo- and in vitro-matured oocytes, respectively, were rinsed and placed in IVC-1 medium (Pope et al. 2006). As assessed by normal morphological appearance after liquefaction, the survival rate of both in vivo- and in vitro-matured oocytes was >90% (93–97%). For in vitro-matured oocytes, cleavage frequencies after IVF of control and vitrified oocytes were 73% (16/22) and 53% (30/57), respectively, as compared to 68% (19/28) after ICSI of vitrified oocytes (P > 0.05). For in vivo-matured oocytes, cleavage frequencies after IVF of control and vitrified oocytes were 55% (18/33) and 35% (6/17), respectively, compared to 50% (10/20) after ICSI of vitrified oocytes (P > 0.05). At 18–20 h after ICSI, 18 presumptive zygotes and four 2-cell embryos derived from vitrified in vitro-matured oocytes and 19 presumptive zygotes produced from seven in vivo-matured and 12 in vitro-matured vitrified oocytes were transferred by laparoscopy into the oviducts of two recipients at 24–26 h after oocyte retrieval. The two recipients were 9-month-old IVF/ET-derived females produced with X-sperm sorted by flow cytometry. At ultrasonography on Day 22, both recipients were pregnant, with three live fetuses observed in one recipient and one live fetus seen in the second recipient. On Day 63 and Day 66 of gestation, four live kittens were born, without assistance, to the two recipients. The one male and three female kittens weighed an average of 131 g. In summary, in vivo viability of zygotes/embryos produced by ICSI of cat oocytes vitrified by the Cryotop method was demonstrated by the birth of live kittens following transfer to recipients.

264 TESTOSTERONE IN THE OOCYTE CULTURE DOES NOT ALTER SEX-RATIO OF IN VITRO PRODUCED BOVINE EMBRYOS

2009 ◽  
Vol 21 (1) ◽  
pp. 229
Author(s):  
C. Díez ◽  
P. Bermejo-Alvarez ◽  
A. Gutiérrez-Adan ◽  
J. N. Caamaño ◽  
M. Muñoz ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Cumulus Cells ◽  
Basic Medium ◽  
Bovine Embryos ◽  
Experimental Conditions ◽  
Vitro Fertilization ◽  
Grant Support ◽  
High Concentrations

The production of sex-known offspring is a main objective in reproductive biotechnology. It has been reported that bovine ova developed in follicles with high concentrations of testosterone in vivo yielded significantly more male embryos in vitro (Grant V et al. 2008 Biol. Reprod. 78, 812–815). In this work we aimed to test the effects of testosterone on sex ratio of bovine embryos produced in fully in vitro conditions. Immature bovine cumulus–oocyte complexes (COCs; n = 750) from slaughterhouse ovaries were cultured in 199 HNaCO3 with polyvinyl alcohol (PVA) 0.1 mg mL–1 as a basic medium. Culture was made in two steps, a 24 h meiotic arrest (roscovitine 25 μm), and a subsequent in vitro maturation period with FSH-LH for 24 h. Testosterone (T-86500, Sigma-Aldrich, St. Louis, MO, USA) was added throughout the entire oocyte culture at 0, 30, 300, and 1500 nm. After in vitro fertilization (Day 0), zygotes were freed of cumulus cells by pipetting, and subsequently cultured in SOF + 6 g L–1 BSA up to Day 3. At this time, embryo development was recorded, and all embryos having 3 or more cells were treated with pronase to remove the zona pellucida. Zona-free embryos were washed in PBS containing PVA 0.1 mg mL–1 and individually frozen at –80°C until sex analysis by PCR (Bermejo-Alvarez P et al. 2008 Biol. Reprod. doi:10.1095/biolreprod.108.070169). A total of 252 embryos from 5 replicates were sexed. Data for development and sex-ratio are presented as % LSM ± SD. There were no interactions between testosterone treatment, embryonic sex, and embryonic stage analyzed. Testosterone did not affect development rates (P > 0.05) at any stage: cleavage (47.8 ± 6.8, 56.5 ± 6.8; 50.9 ± 6.8; 62.2 ± 6.8), 3 to 4 cells (40.6 ± 5.2, 45.8 ± 5.2; 37.8 ± 5.2; 47.7 ± 5.2) and >5 cells rates (24.5 ± 4; 27.3 ± 4; 21.3 ± 4; 25.3 ± 4) for 0, 30, 300, and 1500 nm testosterone, respectively. Cumulative percentages of male embryos were as follows: 53 ± 8 (n = 56), 42.6 ± 8 (n = 52), 53.6 ± 6 (n = 81) and 57.6 ± 8 (n = 63) for 0, 30, 300, and 1500 nm groups respectively (P > 0.05). These results show that the testosterone effects on oocyte ability to select Y-chromosome bearing spermatozoa are not reproducible in vitro under the present experimental conditions. Grant support: MEC, project AGL2008-01530; RTA2008-0082; M. Muoz is supported by FICYT.

211 IN VIVO MATURATION AND IN VITRO FERTILIZATION OF ALPACA OOCYTES

2011 ◽  
Vol 23 (1) ◽  
pp. 204 ◽  
Author(s):  
W. Huanca ◽  
R. L. Condori ◽  
M. A. Chileno ◽  
J. Cainzos ◽  
J. J. Becerra ◽  
...  
Keyword(s):  
Cumulus Cells ◽  
Hypodermic Needle ◽  
High Humidity ◽  
Cleavage Rate ◽  
Sodium Pyruvate ◽  
Vitro Fertilization ◽  
Collection Rate ◽  
Follicular Response

The objectives of the study were to evaluate the ovarian follicular response, cumulus–oocyte complex (COC) collection rate, fertilization, and culture of COC collected from alpacas after treatment with 2 different gonadotropins. Female alpacas were assigned to Group 1 (n = 8), 200 mg of FSH (Folltropin, Bioniche, Belleville, Ontario, Canada) divided b.i.d. for 3 days, plus a single IM dose of 1000 IU of hCG (Chorulon, Intervet, Salamanca, Spain) 24 h after the last FSH treatment; or Group 2 (n = 10), 750 IU of eCG (Folligon, Intervet) as a single dose, plus a single IM dose of 1000 IU of hCG on Day 3 after eCG treatment (Day 0 = start of the superstimulatory treatment). At 20 to 22 h post-hCG treatment, the ovaries were surgically exposed and COC were aspirated from follicles ≥6 mm and evaluated. The COC with a homogeneous cytoplasm and 2 or more layers of cumulus cells were transferred to plates with a 40-μL drop of TCM-199 maturation medium supplemented with 10% FCS (vol/vol) plus 0.5 μg mL–1 of FSH, 10 μg mL–1 of hCG, 0.2 mM sodium pyruvate, 50 μg mL–1 of gentamicin, and 1 μg mL–1 of oestradiol under mineral oil with 10 to 12 oocytes/drop and maturated 24 h at 39°C in an atmosphere of 5% CO2 and high humidity. After maturation, COC were removed and fertilized in vitro using epididymal sperm. Testes were collected from mature males from a slaughterhouse and transported to the laboratory. The caudal epididymide was isolated. A prick was made on the convoluted tubules with a sterile hypodermic needle and the fluid, rich in spermatozoa, was aspirated in syringes containing 2 mL of Tris-fructose egg yolk extender. Motile spermatozoa were obtained by centrifugation at 600 × g on a Percoll discontinuous gradient (45.0:22.5%) for 10 min. The supernatant was then removed by aspiration and the pellet was resuspended in TL-HEPES and centrifuged again at 300 × g for 5 min. The pellet was resuspended in TL-stock. Gametes were co-incubated for 18 h at 39°C with 5% CO2 and high humidity. Presumptive zygotes were cultured in KSOM medium supplemented with 1 mM glutamine, 0.3 mM sodium pyruvate, 50 μg mL–1 of gentamicin, EDTA, essential and nonessential amino acids, and BSA for 3 days and cultured in SOF medium for 7 days. Embryo development was evaluated at 72 h and 7 days. Data were subjected to ANOVA. The number of follicles ≥6 mm did not differ at the time of COC collection (19.3 ± 5.7 and 21.5 ± 7.3), and the number of COC collected was 16.7 ± 5.3 and 17.3 ± 6.6 for the FSH group and the eCG group, respectively. The cleavage rate was 45.2 and 42.1% for the FSH group and the eCG group, respectively, at 72 h of culture, and the blastocyst stage at Day 7 (22.2 v. 19.3) did not differ between treatments. In conclusion, the FSH and eCG treatments did not differ in the ovarian follicular response, COC collection rate, fertilization, and culture of COC. Both gonadotropins can be used in the IVF protocol for alpacas. Grant 064 FINCyT-PIBAP 2008 and Grant 032-2009 PROCYT–CONCYTEC.

Steroid secretion by cumulus cells isolated from human preovulatory follicles

1985 ◽  
Vol 108 (3) ◽  
pp. 407-413 ◽  
Author(s):  
Torbjörn Hillensjö ◽  
Anita Sjögren ◽  
Björn Strander ◽  
Nieves Andino
Keyword(s):  
Cumulus Cells ◽  
Human Oocyte ◽  
Functional Difference ◽  
Fertilization Program ◽  
Hormonal Stimulation ◽  
Vitro Fertilization ◽  
Follicular Maturation ◽  
Preovulatory Follicles

Abstract. The secretion of progesterone, testosterone, and oestradiol by intact human oocyte-cumulus complexes in vitro was examined in incubations lasting 6–24 h. The complexes were aspirated from preovulatory follicles in 32 women who, due to tubal disease, were participating in an in vitro fertilization program. In 12 of the women follicular maturation was induced with clomiphene and human chorionic gonadotrophin (hCG), in 13 women with human menopausal gonadotrophin (hMG) and hCG and in 7 women with a combination of clomiphene-hMG plus hCG. The net secretion of steroids into the fertilization medium was studied before (0-6 h) and after (6–24 h) the addition of sperm, by RIA of aliquots removed at specific times. A high and sustained secretion of progesterone was found both before and after insemination. Testosterone secretion remained at a low and constant level while a net release of oestradiol was found mainly during the first hours of incubation. The release of steroids, particularly progesterone, varied according to the mode of hormonal stimulation in vivo and was highest in complexes from clomiphene-hMG-treated women, probably reflecting different maturity of the aspirated follicles. In a second series of experiments the dispersed cumulus cells were recovered after fertilization and cultured as monolayers for 2–4 days. The cells underwent spontaneous luteinization and secreted high amounts of progesterone. These results extend previous work in animals showing that also in the human the periovulatory cumulus cells are steroidogenically active. The results also suggest a functional difference in the cumulus cells related to the mode of ovulation induction.

scholarly journals Quadrupling efficiency in production of genetically modified pigs through improved oocyte maturation

2017 ◽  
Vol 114 (29) ◽  
pp. E5796-E5804 ◽  
Author(s):  
Ye Yuan ◽  
Lee D. Spate ◽  
Bethany K. Redel ◽  
Yuchen Tian ◽  
Jie Zhou ◽  
...  
Keyword(s):  
Assisted Reproductive Technologies ◽  
Cumulus Cell ◽  
Cumulus Cells ◽  
Reproductive Technologies ◽  
Oocyte Quality ◽  
Blastocyst Stage ◽  
Vitro Fertilization ◽  
Fourfold Increase

Assisted reproductive technologies in all mammals are critically dependent on the quality of the oocytes used to produce embryos. For reasons not fully clear, oocytes matured in vitro tend to be much less competent to become fertilized, advance to the blastocyst stage, and give rise to live young than their in vivo-produced counterparts, particularly if they are derived from immature females. Here we show that a chemically defined maturation medium supplemented with three cytokines (FGF2, LIF, and IGF1) in combination, so-called “FLI medium,” improves nuclear maturation of oocytes in cumulus–oocyte complexes derived from immature pig ovaries and provides a twofold increase in the efficiency of blastocyst production after in vitro fertilization. Transfer of such blastocysts to recipient females doubles mean litter size to about nine piglets per litter. Maturation of oocytes in FLI medium, therefore, effectively provides a fourfold increase in piglets born per oocyte collected. As they progress in culture, the FLI-matured cumulus–oocyte complexes display distinctly different kinetics of MAPK activation in the cumulus cells, much increased cumulus cell expansion, and an accelerated severance of cytoplasmic projections between the cumulus cells outside the zona pellucida and the oocyte within. These events likely underpin the improvement in oocyte quality achieved by using the FLI medium.

scholarly journals 213EFFECTS OF TIME OF MATURATION AND SHEEP SERUM ON IN VITRO FERTILIZATION IN THE ENDANGERED ELD'S DEER (CERVUS ELDI THAMIN) OOCYTES

2004 ◽  
Vol 16 (2) ◽  
pp. 228
Author(s):  
B. Siriaroonrat ◽  
P. Comizzoli ◽  
N. Songsasen ◽  
R.E. Spindler ◽  
S.L. Monfort ◽  
...  
Keyword(s):  
In Vitro Fertilization ◽  
Calf Serum ◽  
Genetic Material ◽  
Cumulus Cells ◽  
Fertilization Success ◽  
Estrous Cycles ◽  
Vitro Fertilization ◽  
Offspring Production ◽  
Oviduct Fluid

The Eld’s deer, native to Southeast Asia, is threatened with extinction. Although artificial insemination is effective for offspring production, in vitro fertilization (IVF) would be more useful for rapidly disseminating genetic material from valuable founders. The objectives of this study were to: 1) determine if oocytes recovered from exogenous gonadotropin-treated hinds require additional in vitro maturation;; and 2) assess if fertilization is enhanced by supplementing Deer Synthetic Oviduct Fluid (DSOF;; Berg DK et al., 2003 Theriogenology 59, 189–205) with 1-day postestrus sheep serum (SS). Estrous cycles in Eld’s deer hinds (n=10) were synchronized with PGF2α analog (Lutalyse™, 500mg), followed by a 14-day intravaginal CIDR-G insertion;; ovine FSH (Ovagen™; 0.05 unit×8 injections) was administered at 12-h intervals beginning 84h before CIDR-removal. COCs (n=160) were retrieved laparoscopically 40–46h post-CIDR-removal and either fixed or matured in vitro (for 12h v. 24h) in TCM-199 (Earle’s salt) supplemented with 0.33mM pyruvate, 2mM glutamine, 100IUmL−1 penicillin, 100μgmL−1 streptomycin, 10% fetal calf serum, 5μgmL−1 FSH and LH and 1μgmL−1 E2 (5% CO2, 38.5°C). After 12- or 24-h IVM, cumulus cells were partially removed and oocytes (n=110) fertilized in DSOF with pooled frozen-thawed sperm (3 males;; 2×106 motile sperm mL−1), in the absence or presence of SS (20%, v/v). Additional oocytes (n=18) were used for parthenogenetic control. At 20-h postinsemination, presumptive zygotes were fixed and stained (Hoechst 33342) to assess fertilization success (presence of two pronuclei). Data were analyzed by ANOVA. Overall, 16.0±2.6 (mean±SEM) COCs were recovered/female. The majority of COCs were of excellent quality (grade I; 67.7±3.8%). At time of aspiration, 85% of the oocytes (n=11/13) were in metaphase I stage, 7.5% in telophase and 7.5% degenerate. No parthenogenic activation was observed. Likewise, no polyspermy was observed in any treatment. Fertilization was higher (P<0.05) in oocytes matured for 24h and fertilized in the absence (64.4±3.1%) compared to presence (26.9±11.2%) of SS. In the absence of SS, a higher (P<0.05) proportion of oocytes were fertilized after 24h (64.4±3.1%) compared to 12h (27.1±9.0%) IVM. There was no effect (P>0.05) of SS on fertilization among oocytes subjected to 12-h IVM (27.1±9.0% v. 12.5±9.5%). When SS was present during fertilization, no difference (P>0.05) was observed among oocytes matured for 12 or 24h. Results demonstrate that: 1) Eld’s deer oocytes require an additional 24-h IVM to complete maturation;; 2) DSOF supports sperm-oocyte interaction;; and 3) SS is not essential for successful fertilization. (Supported by Morris Animal Foundation.)

208 IN VITRO FERTILIZATION UNDER SIMULATED STRESS AND SUBSEQUENT IN VITRO EMBRYO PRODUCTION IN THE PIG

2011 ◽  
Vol 23 (1) ◽  
pp. 203
Author(s):  
R. González ◽  
Y. Brandt
Keyword(s):  
Cumulus Cells ◽  
Early Embryo ◽  
Reproductive Hormones ◽  
Blastocyst Development ◽  
Cleavage Rate ◽  
Vitro Fertilization ◽  
Endocrine Profile ◽  
Serum Gonadotropin

Fertilization is a crucial step for successful reproduction and can be negatively influenced by stressful situations. It is generally accepted that stress affects reproduction, altering the endocrine profile of the female. An altered hormonal environment where the oocyte is developing could affect critical processes such as fertilization. Using a mixed in vivo–in vitro system, we assessed the ability of the oocyte to undergo fertilization and early development after exposure to blood plasma from sows that had experienced simulated stress through repeated injections of adrenocorticotropic hormone (ACTH) before ovulation (known concentrations of cortisol and reproductive hormones as well as exact ovulation time assessed by ultrasonography). Oocytes (n = 926, 7 replicates) collected from abattoir ovaries were matured in TCM-199 with BSA supplemented with hormones (10 IE mL–1 of pregnant mare serum gonadotropin and 5 IE mL–1 of hCG) and insulin-transferrin-selenium (5 μL mL–1) for 24 h, followed by 22 h without supplements. During IVF, gametes were exposed to 10% of pooled plasma (n = 3 per treatment) collected approximately 1 h before ovulation from ACTH-treated sows (A group), nontreated control sows (C group), or media with BSA (B group) for 24 h. Fresh semen was added at 5 × 105 cells mL–1. Afterward, the remaining cumulus cells and sperm were removed from oocytes by vortexing (1 min), and presumptive zygotes were placed in culture medium (porcine zygote medium). Cleavage rate was assessed at 48 h post-insemination (hpi) and the embryos (n = 433, 7 replicates) were cultured up to Day 7 and stained with Hoechst 33342 (10 μg mL–1) to count the total number of nuclei. In addition, non-cleaved oocytes were stained at 48 hpi with Hoechst to assess sperm-zona binding. Binding to the zona was assessed only in oocytes found to be matured. Statistical analysis was done using Kruskal-Wallis ANOVA and the Mann-Whitney U test. The number of spermatozoa bound to the zona pellucida was higher in the B group, and binding was notably negatively affected in the ACTH group (0.43 ± 0.18, 35.93 ± 2.50, and 3.44 ± 1.04 for the A, B, and C group, respectively; P < 0.001). Cleavage rate (over total number of presumptive zygotes) in the A group (30.71 ± 3.76%) was significantly lower than in the control groups (59.93 ± 4.0 and 52.2 ± 5.31% for the B and C group, respectively; P < 0.01). Blastocyst rate expressed over the total number of embryos was reduced in the A group (9.40 ± 5.20%) compared with the controls (27.10 ± 5.79 and 25.66 ± 5.28% in the B and C group, respectively; P < 0.05). However, no differences were found in the total number of nuclei in the blastocysts. The results suggest that fertilization is a sensitive event that could be negatively influenced by stress, subsequently affecting early embryo development. A reduced number of spermatozoa attached to the zona and a lower number of embryos and lower blastocyst development were observed in the simulated-stress group. Further studies would help to elucidate which (in the oocyte, spermatozoon, or both) mechanisms are being affected by ACTH-simulated stress around fertilization. Data are expressed as mean ± SEM. Funded by Formas.

Gene expression profile of cumulus cells derived from cumulus - oocyte complexes matured either in vivo or in vitro

2009 ◽  
Vol 21 (3) ◽  
pp. 451 ◽  
Author(s):  
Dawit Tesfaye ◽  
Nasser Ghanem ◽  
Fiona Carter ◽  
Trudee Fair ◽  
Marc-André Sirard ◽  
...  
Keyword(s):  
Transcript Abundance ◽  
Cumulus Cells ◽  
Developmental Competence ◽  
Lh Surge ◽  
Expected Time ◽  
Custom Made ◽  
Developmental Capacity ◽  
Transcript Profiles

Although it is well established that maturation conditions have a clear influence on oocyte developmental competence, it is not known whether this could be due to downstream effects of perturbation of the transcript profile of the oocyte’s adjacent cumulus cells. Therefore, the aim of the present study was to compare the transcript profiles of cumulus cells derived from cumulus–oocyte complexes (COCs) matured in vitro or in vivo. Using a previously validated combined synchronisation and superstimulation protocol, COCs were recovered from beef heifer ovaries just before the expected time of the LH surge and matured in vitro, while in vivo-matured COCs were recovered just before ovulation (20 h after the LH surge). A custom-made cDNA microarray containing 2278 granulosa/cumulus transcripts was used for target and dye-swap hybridisations. In all, 64 genes were differentially expressed between the two groups. Transcript abundance of key genes associated with cumulus expansion (TNFAIP6) and regulation of oocyte maturation (INHBA and FST) were upregulated in in vivo-derived cumulus cells. However, cumulus cells derived from IVM COCs were enriched with genes involved in response to stress (HSPA5 and HSP90AB1). Quantitative real-time polymerase chain reaction confirmed the array results for eight of 10 genes selected for validation. The data presented here reveal that differences in oocyte developmental capacity after maturation in vitro or in vivo are accompanied by distinct differences in transcript abundance of the surrounding cumulus cells.

Effect of cyanocobalamin on oocyte maturation, in vitro fertilization, and embryo development in mice

Zygote ◽  
2020 ◽  
pp. 1-8
Author(s):  
Tamana Rostami ◽  
Fardin Fathi ◽  
Vahideh Assadollahi ◽  
Javad Hosseini ◽  
Mohamad Bagher Khadem Erfan ◽  
...  
Keyword(s):  
Embryo Development ◽  
Oocyte Maturation ◽  
Cumulus Cells ◽  
Treated Group ◽  
Blastocyst Stage ◽  
Control Group ◽  
Vitro Fertilization ◽  
Maturation In Vitro

Summary The aim of this study was to investigate the effect of cyanocobalamin supplementation on in vitro maturation (IVM), in vitro fertilization (IVF), and subsequent embryonic development competence to the blastocyst stage, and in vitro development of mouse 2-cell embryos. Cumulus cells were prepared from mouse cumulus–oocyte complexes (COCs) and incubated for 24 h in an in vitro culture (IVC) medium that contained different concentrations of cyanocobalamin (100, 200, 300 or 500 pM). We collected 2-cell embryos from superovulated NMRI mice and cultured them in the same concentrations of cyanocobalamin (100, 200, 300 or 500 pM). After 42 h of IVM, we observed significantly increased oocyte maturation in the 200 pM cyanocobalamin-treated group compared with the control group (P < 0.0001). Mature oocytes cultured in 200 pM cyanocobalamin were fertilized and cultured in IVC medium with cyanocobalamin (100, 200, 300 or 500 pM) during early embryogenesis. The matured oocytes that were cultured in 200 pM cyanocobalamin had significantly higher 2-cell development rates compared with the control oocytes (P < 0.01). Embryos obtained from in vitro mature oocytes and in vivo fertilized oocytes that were cultured in 200 pM cyanocobalamin had significantly greater frequencies of development to the blastocyst stage and a significant reduction in 2-cell blocked and degenerated embryos compared with the control embryos (P < 0.0001). Embryos derived from oocytes fertilized in vivo with 200 pM cyanocobalamin had a higher percentage of blastocyst embryos compared with those derived from matured oocytes cultured in vitro (P < 0.0001). These finding demonstrated that the effects of cyanocobalamin on oocyte maturation, fertilization, and embryo development in mice depend on the concentration used in IVC medium.

scholarly journals Production, Evaluation, Cultivation and In vitro Fertilization of Cattle Oocytes: Recent Trends in Reproductive Biotechnologies in Animal Breeding : A Review

2021 ◽  
Vol 14 (4) ◽  
pp. 1452-1458
Author(s):  
Vladimir Aleksandrovich Pleshkov
Keyword(s):  
Genetic Material ◽  
Cumulus Cells ◽  
The Body ◽  
Hypodermic Needle ◽  
Cattle Breeding ◽  
Vitro Fertilization ◽  
Recent Trends ◽  
Normal Fertilization ◽  
Donor Cows

The article presents the results of assessing reproductive biotechnology for cattle breeding. The issues of obtaining genetic material from bulls-producers and oocytes from donor cows, for their further cultivation and obtaining embryos, in order to replicate highly productive offspring from valuable animals, are considered. Oocyte production was analyzed in three different ways: puncture, section, and aspiration. A total number of 156 oocyte-cumulus complexes (OCCs) were collected out of 40 ovaries by puncture – 50 pcs, section – 47 pcs, and aspiration – 59 pcs. The results showed that puncture and section gave significantly higher total OCCs per an ovary (4.16 and 4.0, respectively) than aspiration (3.68), but a higher number of normal (grade A and B) OCCs per an ovary was observed with aspiration (2.5) than with puncture (1.82) and section (2.00). During aspiration, oocyte-cumulus complexes were collected from the surface of follicles with a diameter of 3 to 8 mm using a needle. During puncture, all surfaces were pierced with a hypodermic needle; during section, incisions were made along the entire ovarian surface with a scalpel, that is, all sizes of superficial follicles were collected. OCCs were divided into 4 classes based on cumulus and nucleus cells: grade A – oocytes completely surrounded by cumulus cells; Grade B – oocytes partially surrounded by cumulus cells; Grade C – oocytes not surrounded by cumulus cells; and grade D – degeneration observed in both oocyte and cumulus cells. Grades A and B were considered normal, while grades C and D were considered to be damaged. The obtained oocytes were cultured and fertilized in vitro, which means that their fertilization with sperm occurred under artificially maintained optimal conditions outside the body. Normal fertilization results are zygote formation with male and female pronuclei (PN). As a result of the conducted fertilization of 251 mature oocytes, 142 fertilizations were successful, which amounted to 56.57%.

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