Births of kittens produced by intracytoplasmic sperm injection of domestic cat oocytes matured in vitro

2000 ◽  
Vol 12 (8) ◽  
pp. 423 ◽  
Author(s):  
M. C. Gómez ◽  
C. E. Pope ◽  
R. Harris ◽  
A. Davis ◽  
S. Mikota ◽  
...  
Keyword(s):  
Intracytoplasmic Sperm Injection ◽  
Polar Body ◽  
Blastocyst Stage ◽  
Domestic Cat ◽  
Oocyte Activation ◽  
Morula Stage ◽  
Cytoplasmic Maturation ◽  
Vitro Development

In Experiment 1, cleavage frequency and in vitrodevelopment of domestic cat embryos produced after in vitro maturation of oocytes obtained from ovaries after ovariohysterectomy (in vivo) with that of oocytes retrieved from follicle-stimulating hormone-treated donors at 24 h after administration of luteinizing hormone (in vivo) and fertilization by intracytoplasmic sperm injection (ICSI) or IVF were compared. In each group presumptive zygotes were assessed for cleavage on IVC Days 1 and 4 and for development to blastocysts on IVC Day 7. In vitro matured oocytes had lower frequencies of meiotic maturation (59.2% v. 66.5%), cleavage at Day 1 (41.4% v. 64.9%) and development to the morula stage at Day 4 (65.8% v. 87.9%) than did in vivo matured oocytes, after ICSI and IVF. Development to the blastocyst stage was lower in in vitro matured oocytes (19.0%) than in vivo matured oocytes (29.5%) after ICSI. In Experiment 2, we evaluated the capacity of sperm injected oocytes without a visible polar body to undergo cleavage and in vitro development. More in vivo matured than in vitro matured oocytes underwent cleavage at Day 1 (46.6% v. 12.6%) and developed to the morula stage by Day 4 (66.7% v. 46.1%), but no blastocysts were obtained at Day 7 in either group. In Experiment 3, we evaluated the in vivo viability of domestic cat embryos derived from ICSI of in vitro matured oocytes. Morula stage embryos were transferred to 18 domestic cat recipients either on Day 4 or 5 after oocyte recovery. A total of 3 domestic cat recipients were pregnant after transfer to recipients on Day 5. Two pregnant cats delivered two normal and healthy live male kittens on Day 68 of gestation and the remaining cat delivered a male kitten on Day 62 that died during the last two days of gestation. These results demonstrate that: (1) inadequate cytoplasmic maturation of in vitro matured domestic cat oocytes is the main cause of deficient oocyte activation; (2) the injection of oocytes without a visible polar body is a useful technique to evaluate oocyte cytoplasmic maturation; and (3) blastocysts obtained after ICSI of in vitro matured oocytes are viable and not a result of parthenogenesis.

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.

98 Assessing Endangered Felid Puma concolor Sperm Fertility by In Vitro Fertilization with Domestic Cat Oocytes

2018 ◽  
Vol 30 (1) ◽  
pp. 188
Author(s):  
M. Duque ◽  
A. Sestelo ◽  
D. F. Salamone
Keyword(s):  
Puma Concolor ◽  
Blastocyst Stage ◽  
Domestic Cat ◽  
Oocyte Activation ◽  
Cleavage Rate ◽  
Vitro Fertilization ◽  
Sperm Suspension ◽  
Morula Stage ◽  
Cryopreserved Sperm

The Puma concolor population has been decreasing during the last 30 years. Semen cryopreservation of this species has been accomplished successfully and offers the possibility of preserving endangered species. We previously showed that fertilizing capability of wild felid spermatozoa can be evaluated using intracytoplasmic sperm injection (ICSI) with in vitro-matured domestic cat oocytes (Moro et al. 2014 Reprod. Domest. Anim. 49, 693-700). Due to the lack of homologous oocytes, we evaluated the capability of the Puma concolor sperm to induce domestic cat oocyte fertilization and subsequent pre-implantation embryo development. In the present study, cryopreserved sperm obtained by electroejaculation from five different males were used for IVF of in vitro-matured (IVM) domestic cat oocytes. Straws were thawed by exposing them to air for 10 s and then immersing in a 37°C water bath for 30 s. The contents of the straws were poured into a sterile 1.5-mL microtube pre-warmed to 37°C. The sperm suspension was diluted (1:3 v/v) by the slow (drop-by-drop) addition of a modified Tyrode’s solution. For IVF, IVM oocytes (n = 370) were co-incubated with 0.5 × 105 motile spermatozoa mL−1 in an atmosphere of 21% O2 in air at 38.5°C for 18 to 20 h. Presumptive zygotes were cultured in vitro in 50-μL drops of modified Tyrode’s medium on 6.5% CO2 in air at 38.5°C. Cleavage was determined at 48 h post-fertilization, and 5% FBS was added at Day 5 of in vitro culture. Blastocyst stage was evaluated at Day 8. Results (mean ± SEM) showed a high cleavage rate (179/370, 49.0 ± 4.0%), and a high development to morula stage (137/370, 34.4 ± 7.2%), and to blastocyst stage (94/370, 23.4 ± 4.7%) for all males. These results indicated that Puma concolor spermatozoa can induce domestic cat oocyte activation and development to blastocyst stage in similar rates to domestic cat homologous IVF: IVM oocytes (n = 291), cleavage rate (199/291, 67.1 ± 6.1%), development to morula stage (144/291, 47.8 ± 4.9%), and to blastocyst stage (86/291, 30.1 ± 1.6%). In conclusion, we demonstrated that domestic cat oocyte can be used to evaluated cryopreserve sperm samples from another felid species.

scholarly journals 77CLONED EMBRYO DEVELOPMENT IN VITRO: COMPARISON OF CONVENTIONAL AND INDUCED ENUCLEATION PROCEDURES FOR BOVINE CYTOPLAST PREPARATION

2004 ◽  
Vol 16 (2) ◽  
pp. 160
Author(s):  
M.-K. Wang ◽  
E.W. Overstrom
Keyword(s):  
Embryo Development ◽  
Polar Body ◽  
Blastocyst Stage ◽  
In Vitro Development ◽  
Uv Illumination ◽  
Development In Vitro ◽  
Second Polar Body ◽  
Vitro Development

Induced enucleation (IE) of oocytes with demecolcine produces competent ooplasts for SCNT as demonstrated previously in mouse, goat, cow and pig. Whether bovine IE cytoplasts are more or less competent than conventionally enucleated MII oocytes to support nuclear reprogramming of somatic chromatin and embryo development in vitro is not known. This study compared in vitro development of cloned bovine embryos produced by conventional and IE enucleation methods. Three experimental groups were: (1) Parthenogenetic controls. In vitro-matured, MII-arrested bovine oocytes were activated by a single (1×Act, 10μM ionomycin in Tyrodes-HEPES, 5min) or double activation (2×Act; 1×Act, wash 5min, 10μgmL−1 cycloheximide [CHX] 20min, repeat 1×Act) followed by incubation in CHX and 5μgmL−1 cytochalasin B (CB) for 6h, and then culture (BARC medium) for 7 days. (2) Conventional SCNT. MII oocytes were enucleated by micromanipulation in HEPES-buffered enucleation medium (BARC containing 7.5μgmL−1 CB, 5μgmL−1 Hoechst 33342, 10% FBS) under UV illumination (3–5s). Donor cells (fibroblasts, passage 7–9) were inserted into the perivitelline space, and the reconstructed couplets activated (1×Act). Reconstructed couplets were then electrofused, placed in BARC medium containing 10μgmL−1 CHX and 5μgmL−1 CB (6h), and then cultured for 7 days. (3) IE SCNT. MII oocytes were activated (1×Act), placed into BARC-5% FBS containing 0.4μgmL−1 demecolcine (DEME), 10μgmL−1 CHX, 2μgmL−1 cytochalasin D for 20min, then 20min without DEME, then returned to DEME. At 1–1.5h post-activation, the extruding second polar body (PB2) containing nuclear chromatin was removed by micromanipulation, couplets were reconstructed and fused as above, and additionally activated (two pulses, 20–30V/mm, 20μs). Embryos were cultured in 10μgmL−1 CHX and 5μgmL−1 CB medium for 4–5 hour, then BARC for 7 days. The results (Table 1) reveal that 2×Act increases embryo development at Day 2, but not Day 7. Further, there are no significant differences in embryo development rates between conventional and IE SCNT protocols. Respectively, 46%, 32% and 21% of cleaved control (1×Act), conventional and IE embryos developed to 16 cells on Day 7. In vitro development of cleavage embryos to the blastocyst stage was greater in controls (25–32%) than in conventional (22%) and IE (17%) SCNT groups on Day 7. Further comparisons of in vivo development between conventional and IE SCNT methods following embryo transfer are warranted. Supported by ACT, Cyagra and USDA NRI \#2001-35205-09966. Table 1 Embryo development: Conventional v. induced enucleation

scholarly journals 160EFFECTS OF EXTRACELLULAR ION CONCENTRATIONS ON IN VITRO DEVELOPMENT OF DOMESTIC CAT IVF EMBRYOS

2004 ◽  
Vol 16 (2) ◽  
pp. 202 ◽  
Author(s):  
W.F. Swanson ◽  
A.L. Manharth ◽  
J.B. Bond ◽  
H.L. Bateman ◽  
R.L. Krisher ◽  
...  
Keyword(s):  
Culture Media ◽  
Ionic Composition ◽  
Cell Number ◽  
Blastocyst Stage ◽  
Domestic Cat ◽  
Embryo Viability ◽  
Blastocyst Development ◽  
In Vitro Development ◽  
Vitro Development

Domestic cat embryos typically are cultured in media formulated for somatic cells or embryos from rodents or livestock species. Under these conditions, blastocyst development has been inconsistent and delayed relative to embryos grown in vivo, and embryo viability following transfer has been low. Our goal is to systematically define the culture requirements of the feline embryo to improve embryo development and viability. The objective of this study was to determine the ionic (NaCl, KCl, KH2PO4, and CaCl2:MgSO4) preferences of domestic cat IVF embryos. Anestral female cats were injected (i.m.) with 150IU eCG followed 84h later by 100IUhCG. Oocytes were recovered via laparoscopic follicular aspiration approximately 24h post-hCG injection (Day 0). Semen was collected from one of two males by means of an artificial vagina and washed once in HEPES-buffered IVF medium. Mature cumulus-oocyte complexes were co-incubated with 2.5–5×105 motile sperm mL−1 in IVF medium (100mM NaCl, 4.0mM KCl, 1.0mM KH2 PO4, 2.0mM CaCl2, 1.0mM MgSO4-7H2O, 25.0mM NaHCO3, 3.0mM glucose, 0.1mM pyruvate, 6.0mM L-lactate, 1.0mM glutamine, 0.1mM taurine, 1×MEM nonessential amino acids, 50μgmL−1 gentamicin, and 4.0mgmL−1 BSA) for 19 to 22h in 6% CO2 in air (38.7°C). Cumulus cells were removed and embryos cultured (8–11 embryos/50μL drop; 6% CO2, 5% O2, 89% N2, 38.7°C) in media containing 100.0 or 120.0mM NaCl, 4.0 or 8.0mM KCl, 0.25 or 1.0mM KH2PO4, and 1.0mM:2.0mM or 2.0mM:1.0mM CaCl2:MgSO4 (2×2×2×2 factorial design). The remaining components of the culture medium were identical to the IVF medium (but w/o gentamicin). Development to the blastocyst stage by Day 6, metabolism (glycolysis and pyruvate) of each blastocyst, and final cell number (Hoechst 33342 staining) of all embryos were evaluated. Final cell number of cleaved embryos and development to the blastocyst stage were analyzed using analysis of variance in the GLIMMIX macro of SAS. A total of 236 oocytes were inseminated, yielding 128 cleaved embryos (54%), including 6 blastocysts (4.7% of cleaved embryos). Cell number was not (P>0.05) affected by NaCl, KCl, or KH2PO4 concentrations, but tended (P=0.057) to be higher after culture in 2.0mM:1.0mM CaCl2:MgSO4. Treatments did not significantly affect (P>0.05) development to the blastocyst stage, but numerically more blastocysts were produced in 100.0mM NaCl (4/6), 8.0mM KCl (5/6), or 1.0mM KH2PO4 (5/6). Both CaCl2:MgSO4 ratios resulted in 3 blastocysts. Blastocysts contained 61.08±5.1 (mean±SEM, n=6) cells and actively metabolized glucose (glycolysis, 3.7±0.8pmol/embryo/3h or 0.06±0.01pmol/cell/3h) and pyruvate (0.75±0.27pmol/embryo/3h or 0.013±0.005pmol/cell/3h). These results suggest that the ionic composition of culture media influences the in vitro development of cat IVF embryos. (Supported by NIH grant RR15388.)

Different activation treatments for successful development of bovine oocytes following intracytoplasmic sperm injection

Zygote ◽  
2003 ◽  
Vol 11 (1) ◽  
pp. 69-76 ◽  
Author(s):  
S.A. Ock ◽  
J.S. Bhak ◽  
S. Balasubramanian ◽  
H.J. Lee ◽  
S.Y. Choe ◽  
...  
Keyword(s):  
Intracytoplasmic Sperm Injection ◽  
Chromosomal Abnormality ◽  
Polar Body ◽  
Ultrastructural Changes ◽  
Time Interval ◽  
Oocyte Activation ◽  
Group 4 ◽  
Group 5 ◽  
Bovine Oocytes

In this study, the developmental capacity and cytogenetic composition of different oocyte activation protocols was evaluated following intracytoplasmic sperm injection (ICSI) of in vitro matured bovine oocytes. Motile spermatozoa selected by Percoll density gradient were treated with 5 mM dithiothreitol (DTT) and analysed for ultrastructural changes of the head using transmission electron microscopy (TEM). The alterations in sperm morphology after DTT treatment for different times (15, 30 and 60 min) were 10%, 45-55% and 70-85%, respectively. Further, a partial decondensation of sperm heads was observed after DTT treatment for 30 min. Oocytes were injected with sperm treated with DTT for 30 min. In group 1, sperm injection was performed without any activation stimulus to the oocytes. In group 2, sham injection without sperm was performed without activating the oocytes. Oocytes injected with sperm exposed to 5 μM ionomycin for 5 min (group 3), 5 μM ionomycin + 1.9 mM dimethylaminopurine (DMAP) for 3 h (group 4) and 5 µM ionomycin + 3 h culture in M199 + 1.9 mM DMAP (group 5) were also evaluated for cleavage, development and chromosomal abnormality. Cleavage and development rates in groups 1, 2 and 3 were significantly (p < 0.05) lower than those in groups 4 and 5. The incidence of chromosomal abnormality in the embryos treated directly with DMAP after ionomycin (group 4) was higher than in group 5. We conclude that immediate DMAP treatment after ionomycin exposure of oocytes results in arrest of release of the second polar body, and thus leads to changes in chromosomal pattern. Therefore, the time interval between ionomycin and DMAP plays a crucial role in bovine ICSI.

111 SLOW FREEZING AND VITRIFICATION OF IN VITRO-MATURED DOMESTIC CAT OOCYTES

2007 ◽  
Vol 19 (1) ◽  
pp. 173 ◽  
Author(s):  
J. Braun ◽  
C. Otzdorff ◽  
T. Tsujioka ◽  
S. Hochi
Keyword(s):  
Polar Body ◽  
Blastocyst Stage ◽  
Domestic Cat ◽  
Slow Freezing ◽  
Developmental Potential ◽  
Freezing Medium ◽  
First Polar Body ◽  
Blastocyst Rate ◽  
Chi Square Analysis

The effects of slow freezing or vitrification as well as exposure to the cryoprotective media without cooling and warming of in vitro-matured domestic cat oocytes on the in vitro development to the blastocyst stage was investigated. Cumulus–oocyte complexes were matured for 24 h in TCM-199 supplemented with 3 mg mL−1 BSA, 1 µg mL−1 estradiol, 0.1 IU mL−1 FSH, and 0.0063 IU mL−1 LH. Denuded oocytes with a detectable first polar body were inseminated with 2 × 106 cells mL−1 cauda epididymal spermatozoa for 22 h in TALP solution. Presumptive zygotes were cultured in modified SOF medium at 38.5°C in 5% CO2 in air. For slow freezing, oocytes were equilibrated for 20 min at ambient temperatures in PBS with 20% FCS containing either 1.5 M ethylene glycol (EG) + 0.2 M sucrose or 1.5 M EG + 0.2 M trehalose. Oocytes were loaded into 0.25-mL straws, cooled to −7°C at 2°C min, held for 5 min, seeded, cooled down to −30°C at 0.3°C min, and finally plunged into liquid nitrogen. The straws were thawed for 5 s at room temperature and for 30 s in a waterbath at 30°C. Oocytes were washed 3 times before insemination. In vitro-matured oocytes were exposed to the cryoprotective media for 30 min before they were inseminated and then they were cultured for 7 days. For vitrification (Hochi et al. 2004 Theriogenology 61, 267–275), a minimum-volume cooling procedure using Cryotop (Kitazato Supply Co., Tokyo, Japan) as a cryodevice was applied. No blastocysts could be obtained after slow freezing with a cryoprotective medium containing 0.2 M sucrose. Simple exposure to the same freezing medium after in vitro maturation without cryopreservation resulted in a blastocyst rate of 7.9% (control oocytes, 10.7%; not significant (NS); chi-square analysis). Use of trehalose as an extracellular cryoprotectant resulted in the harvest of one blastocyst (0.6%) after slow freezing. Exposure to the same cryoprotective medium resulted in a blastocyst rate of 10.0% (fresh control, 10.9%; NS). After exposure of in vitro-matured oocytes to the vitrification solution, a blastocyst rate of 16.0% was observed (8/50), which was not statistically different from the blastocyst rate in fresh control oocytes (16.3%; 15/92). No blastocysts could be obtained after vitrification (0/64). The results (Table 1) demonstrate that there is no obvious toxic effect of the cryoprotectants employed here for slow freezing or vitrification on the in vitro-matured oocytes, but the developmental potential of cryopreserved oocytes to the blastocyst stage is severely impaired. Table 1. Effect of slow freezing or exposure to freezing medium of matured cat oocytes on the development to the blastocyst stage in vitro

42 DEVELOPMENT OF PIG EMBRYOS CLONED FROM DONOR CELLS TREATED WITH TRICHOSTATIN A

2008 ◽  
Vol 20 (1) ◽  
pp. 101 ◽  
Author(s):  
J. Li ◽  
Y. Du ◽  
P. M. Kragh ◽  
S. Purup ◽  
K. Villemoes ◽  
...  
Keyword(s):  
Trichostatin A ◽  
Calcium Ionophore ◽  
Blastocyst Stage ◽  
Fibroblast Cells ◽  
Embryonic Genome ◽  
Donor Cells ◽  
Deacetylase Inhibitor ◽  
Vitro Development

Development to the blastocyst stage following nuclear transfer is dependent on the donor cell's ability to reprogram its genome to a totipotent state. Reprogramming of the transferred somatic nuclei must be completed by the time normal activation of the embryonic genome occurs (Solter 2000 Nat. Rev. Genet. 1, 199–207). Recently, Enright et al. (2003 Biol. Reprod. 69, 896–901) reported that in vitro development of cloned cow embryos was improved by treatment of donor cells with a histone deacetylase inhibitor, TrichostatinA (TSA). So far, there are no reports available for adult pig fibroblast cells treated with TSA. The objective of this study was to investigate whether the development of handmade cloned embryos in pig could be improved by using TSA-treated donor cells. Adult pig fibroblast cells were treated with 100, 150, or 200 nm TSA for 24 h, compared to untreated controls, and were then used as donor cells. The cells were electrofused with handmade enucleated pig oocytes separately and were activated with calcium ionophore and cycloheximide. They were subsequently cultured in porcine zygote medium 3 (PZM-3; Yoshioka et al. 2002 Biol. Reprod. 66, 112–119) using the well of the well system (WOW; Vajta et al. 2000 Mol. Reprod. Dev. 55, 256–264). Experiments were repeated 4 times and the data were analyzed with AVEDEV and t-test in Excel (Microsoft Excel 2007). The cleavage rates and the total cell numbers per blastocyst were similar between groups (P > 0.05), as shown in Table 1. However, the cloned blastocyst rate using donor cells treated with 100 nm TSA was higher than in the other groups (69.9 ± 4.7% v. 43.6 ± 4.3%, 43.1 ± 5.8%, or 46.6 ± 3.6%; P < 0.05), as shown in Table 1. These data suggest that proper TSA treatment for donor cells before somatic cloning improves the rate of development of porcine handmade cloned embryos to the blastocyst stage. Further research is needed to examine the in vivo development of embryos reconstructed with TSA-treated donor cells. Table 1. Developmental ability of cloned pig embryos derived fromTSA-treated donor cells

35 EFFECTIVENESS OF MICROWELL-BASED IN VITRO CULTURE SYSTEMS FOR BOVINEZONA-FREE CLONED EMBRYOS

2011 ◽  
Vol 23 (1) ◽  
pp. 124
Author(s):  
C. Feltrin ◽  
M. Machado ◽  
L. M. V. Queiroz ◽  
M. A. S. Peixer ◽  
P. F. Malard ◽  
...  
Keyword(s):  
In Vitro Culture ◽  
Embryo Development ◽  
Zona Pellucida ◽  
Blastocyst Stage ◽  
Aggregation State ◽  
Developmental Potential ◽  
In Vitro Development ◽  
Vitro Development

In vitro embryo production by handmade cloning (HMC) usually requires individual embryo culture, because zona-free embryos cannot be grouped in standard in vitro culture (IVC) protocols. The aim of this study was to evaluate the developmental potential of bovine embryos produced by HMC (Ribeiro et al. 2009 Cloning Stem Cells 11, 377–386) after in vitro culture (IVC) in 3 microwell (WOW) systems. After in vitro maturation, oocytes were denuded and incubated in demecolcine (Ibáñez et al. 2003 Biol. Reprod. 68, 1249–1258), followed by zona pellucida removal, oocyte bisection, embryo reconstruction, electrofusion, and chemical activation. Cloned embryos were allocated to 1 of 3 IVC groups: cWOW: conventional microwells (250 μm, round; Vajta et al. 2000 Mol. Reprod. Dev. 55, 256–264); mWOW: modified microwells (130 μm, conical; Feltrin et al. 2006 Reprod. Fert. Dev. 18, 126); and WOW-PDMS: microwells in polydimethylsiloxane chips (170 μm, cylindrical with microchannels); IVF embryos were used as controls (Bertolini et al. 2004 Reproduction 128, 341–354). Cleavage (Day 2), blastocyst (Day 7), and pregnancy (Day 30) rates were analysed by the chi-square test, for P < 0.05. Results are shown in Table 1. Cleavage rates were similar between groups, but development to the blastocyst stage was higher in IVF controls than cloned embryo groups. Among cloned embryo groups, blastocyst rate was higher in the mWOW group than the conventional and the PMDS-based microchannels. Nevertheless, in vivo development to Day 30 of pregnancy was not different between cloned groups. Our results for in vitro embryo development indicated that the mWOW provided more suitable conditions for embryo development to the blastocyst stage when compared with cWOW or even WOW-PDMS. Among some possible reasons include the physical advantage of a smaller microwell that may better mimic the constraining effect of the zona pellucida on the developing embryo. That may also provide greater blastomere stability, favouring the aggregation state during the first rounds of cleavages, also aiding compaction and subsequent cavitation. The narrower microwell system appeared to have promoted better in vitro development than the conventional and the DMPS-based microwell systems, with no impact on subsequent in vivo development. However, the IVC in the WOW-PDMS system supported reasonable rates of development, in accordance with the current literature. Table 1.In vitro development of bovine IVF and cloned embryos produced after the in vitro culture in distinct IVC systems

17 Effect of the zona-free aggregation on the developmental competence of kodkod (Leopardus guigna) embryos generated by interspecies somatic cell nuclear transfer

2019 ◽  
Vol 31 (1) ◽  
pp. 134
Author(s):  
D. Veraguas ◽  
C. Aguilera ◽  
D. Echeverry ◽  
D. Saez-Ruiz ◽  
F. O. Castro ◽  
...  
Keyword(s):  
Gene Expression ◽  
Somatic Cell ◽  
Blastocyst Stage ◽  
Domestic Cat ◽  
Developmental Competence ◽  
Relative Expression ◽  
Standard Curve ◽  
Morula Stage ◽  
Leopardus Guigna

The kodkod is considered a vulnerable species by the International Union for Conservation of Nature. Phylogenetically, the kodkod is classified in the Leopardus genus, which has only 36 chromosome pairs compared with the domestic cat, which has 38. The proposed hypothesis was that domestic cat oocytes are capable of reprogramming somatic cells from kodkod after interspecies somatic cell NT (SCNT), allowing the in vitro embryo development up to blastocyst stage. Five experimental groups were made based on the technology and culture system: (1) cat embryos generated by IVF (IVF), (2) cat embryos generated by SCNT (Ca1x), (3) aggregated cat embryos generated by SCNT (Ca2x), (4) kodkod embryos generated by interspecies SCNT (K1x), and (5) aggregated kodkod embryos generated by interspecies SCNT (K2x). Interspecies SCNT was performed using a zona-free method. Reconstructed embryos were activated by 2 electrical pulses of 140 kV cm−1 for 40 µs and then incubated for 5h in 10μg mL−1 of cycloheximide and 5μg mL−1 of cytochalasin B. Embryos were cultured in SOF media using the well of the well system in a 5% O2, 5% CO2, and 90% N2 atmosphere at 38.5°C for 8 days. The morulae and blastocysts rates were estimated, and diameter of cloned blastocysts was measured. The relative expression of OCT4, SOX2, and NANOG was evaluated in blastocysts by RT-qPCR using the standard curve method; SDHA was used for normalization. The Kruskal-Wallis test was used to evaluate the developmental parameters and gene expression. The t-test was used to evaluate blastocyst diameter. Statistical differences were considered at P&lt;0.05. The number of replicates was IVF=10, Ca1x=8, Ca2x=6, K1x=3, and K2x=8. The morulae rate was lower when clone embryos were cultured individually (IVF=97/153, 63.4%; Ca2x=28/51, 54.9%; K2x=63/110, 57.3%; Ca1x=48/126, 38.1%; K1x=22/87, 25.3%; P&lt;0.05). In the domestic cat, blastocysts rate was higher in IVF (58/153, 37.9%) and Ca2x (28/51, 29.4%) groups than in the Ca1x group (21/126, 16.7%; P&lt;0.05). No blastocysts were generated in the K1x group (0/87), whereas 5.5% of blastocysts were obtained from the K2x (6/110; 5.5%); this was not statistically different compared with the K1x group (P&gt;0.05). No differences were found in blastocyst diameter between the Ca1x (220.4µm) and Ca2x (251.2µm) groups (P&gt;0.05). However, the diameter of the blastocysts from the K2x group (172.8µm) tended to be lower than that of the blastocysts from the Ca2x group (P=0.05). Regarding gene expression, only 1 of the 6 kodkod blastocysts expressed OCT4, and none expressed SOX2 and NANOG. On the other hand, the relative expression of OCT4 tended to decrease in blastocysts from the Ca1x and Ca2x groups compared with the IVF group (P=0.09), but no differences were found in the expression of SOX2 and NANOG among groups (P&gt;0.05). In conclusion, after interspecies SCNT, domestic cat oocytes support the development of kodkod embryos until the morula stage. However, the embryo aggregation did not significantly improve the blastocyst rate and gene expression.

Comparison of traditional and modified (VitMaster) methods of rabbit embryo vitrification

2009 ◽  
Vol 57 (3) ◽  
pp. 411-416 ◽  
Author(s):  
Krzysztof Papis ◽  
Maciej Korwin-Kossakowski ◽  
Elżbieta Wenta-Muchalska
Keyword(s):  
Liquid Nitrogen ◽  
Supercooled Liquid ◽  
Blastocyst Stage ◽  
Microbiological Contamination ◽  
Cooling Method ◽  
Survival And Development ◽  
Morula Stage ◽  
Rabbit Embryo

In spite of their cryobiological efficacy, minimum-volume vitrification methods suffer from the risk of microbiological contamination and are technically and/or manually demanding. In this study, the effects of a traditional, slightly modified vitrification method and vitrification using supercooled liquid nitrogen (VitMaster) applied for rabbit morula-stage embryos were compared. Embryos were equilibrated in a solution containing 1,2-propanediol (2.72 M) and glycerol (1.36 M) for 7 min and vitrified in 0.25-ml insemination straws after 1-min exposure to a vitrification solution containing additionally 1.0 M sucrose. Cooling was performed in ‘normal’ or supercooled liquid nitrogen. Regardless of the cooling method applied, high in vitro survival and development rates of vitrified embryos were obtained. All embryos were intact after warming, and 61 out of 65 (93.8%) and 23 out of 24 (95.8%) embryos developed to the blastocyst stage after 48-h in vitro culture of embryos vitrified in ‘normal’ or supercooled liquid nitrogen, respectively. The results suggest higher developmental ability of embryos vitrified in supercooled liquid nitrogen (91.7% vs . 83.1% of embryos vitrified traditionally developed to more advanced, expanding and/or hatching blastocyst stages). In vivo survival rate, tested for the traditional vitrification system only, revealed that 36.8% of embryos developed to term. The results show promise for establishing a fully successful method for rabbit embryo vitrification.

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