scholarly journals High in vitro survival rate of sheep in vitro produced blastocysts vitrified with a new method and device

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Sergio Ledda ◽  
Jen M. Kelly ◽  
Stefano Nieddu ◽  
Daniela Bebbere ◽  
Federica Ariu ◽  
...  
Keyword(s):  
Survival Rate ◽  
Survival Rates ◽  
Blastocyst Stage ◽  
Hatching Rate ◽  
High Survival ◽  
Apoptotic Cells ◽  
Embryo Survival ◽  
New Device ◽  
In Vitro Survival

Abstract Background To advance the use of embryo vitrification in veterinary practice, we developed a system in which embryo vitrification, warming and dilution can be performed within a straw. Ovine in vitro produced embryos (IVEP) were vitrified at either early (EBs: n = 74) or fully expanded blastocyst stage (FEBs: n = 195), using a new device named “E.Vit”, composed by a 0.25-mL straw with a 50-μm pore polycarbonate grid at one end. Embryos at each stage (EBs and FEBs) were vitrified by either Two-step (TS) or Multi-step (MS; 6 different concentrations of vitrification solutions) protocol. Non-vitrified embryos (n = 102) were maintained in in vitro culture as a control. Warming consisted of placing the straws directly into 1.5 mL tubes containing a TCM-199 solution with three decreasing concentrations of sucrose. Blastocyst re-expansion, embryo survival and hatching rate were evaluated at 2, 24 and 48 h post warming. The number of apoptotic cells was determined by TUNEL assay. Results Blastocyst re-expansion (2 h) after warming was higher (P < 0.05) in FEBs group, vitrified with the MS and TS methods (77.90% and 71.25%, respectively) compared with the EBs group (MS: 59.38% and TS: 48.50%, respectively). Survival rates of vitrified FEBs after 24 h IVC were higher (P < 0.001) in both methods (MS and TS) than vitrified EBs (MS: 56.25%; TS: 42.42%) and was higher (P < 0.05) in the MS method (94.19%) compared with those in TS (83.75%). After 48 h of culture the hatching rate for FEBs vitrified in MS system (91.86%) was similar to control (91.89%), but higher than FEB TS (77.5%) and EBs vitrified in MS (37.5%) and TS (33.33%). Number of apoptotic cells were higher in EBs, irrespective of the system used, compared to FEBs. The number of apoptotic cells in FEBs vitrified with MS was comparable to the control. Conclusions A high survival rate of IVP embryos can be achieved by the new “E.Vit” device with hatching rates in vitro comparable with control fresh embryos. This method has the potential for use in direct embryo transfer in field conditions.

47 A New Device and Method for Successful Vitrification of In Vitro-Produced Ovine Embryos

2018 ◽  
Vol 30 (1) ◽  
pp. 163
Author(s):  
S. Ledda ◽  
J. M. Kelly ◽  
S. K. Walker ◽  
Y. Natan ◽  
A. Arav
Keyword(s):  
Survival Rate ◽  
Embryo Transfer ◽  
Blastocyst Stage ◽  
Embryo Cryopreservation ◽  
Control Group ◽  
Hatching Rate ◽  
High Survival ◽  
Embryo Survival ◽  
New Device

To advance the use of embryo vitrification technology in veterinary practice, we developed a system in which embryo vitrification, warming, and dilution can be performed within a straw. An in-straw embryo cryopreservation method reduces the need for equipment and technical skills and can facilitate direct embryo transfer to the uterus. This study proposes the use of a new device named “Sarah” that is designed to permit all in-straw embryo cryopreservation procedures. Ovine in vitro-produced (IVP) embryos were vitrified at either early blastocyst stage (EB, n = 65, 6 days post-IVF) or fully expanded blastocyst stage (FB, n = 168, 7 days post-IVF). The vitrification procedure using Sarah constituted a 0.25-mL straw with a capsule having 50-µm pores inserted at one end. Embryos at each stage (EB and FB) were divided into 2 subgroups and vitrified by 1 of 2 methods: (1) multi-step (MS) group-a straw containing 2 embryos was sequentially loaded vertically into 1.5-mL tubes containing 6 different vitrification solutions: 10, 20, 40, 60, 80, or 100% ES (with 100% ES being 7.5% DMSO +7.5% EG + 20% FCS in TCM-199; 90 s each step) followed by 30 s each in 75 and 100% VS (100% VS being 18% DMSO +18% EG + 0.5 M trehalose + BSA in TCM-199); and (2) two-step (TS) group-the straw (2 embryos/straw) was loaded with 100% of ES (5 min), followed by 100% VS solution for 30 s. For both methods, at the end of the preparation steps, the straws were plunged directly into liquid N2. Non-vitrified embryos were maintained in in vitro culture as a control group (n = 102). The warming procedure consisted of placing the straws directly into 5-mL tubes containing 100, 50, 25% WS (WS = 1 M sucrose in TCM-199+ 20% FCS) at 38.6°C (for first solution) and at room temperature for all the rest (5 min each), before being placed into the holding medium. Embryos were recovered from the straws, incubated at 38.6 C in 5% CO2 in air in TCM 199 + 5% FCS, and evaluated for blastocoel re-expansion, embryo survival, and hatching rate at 2, 14, 48 h post-warming. Blastocyst re-expansion (2 h) after warming increased as the developmental stage progressed and was not affected by the vitrification method. In fact, it was significantly (P < 0.05) higher for FB vitrified in the MS and TS methods (77.90% and 71.25%, respectively) compared with the EB method (62.5% and 48.50%, respectively). At 24 h, survival rate of vitrified FB was significantly higher (P < 0.05) in the MS system (95.35%) compared with those in TS (86.25%). Survival rates of FB embryos for both methods (MS and TS) were significantly higher (P < 0.001) than EB embryos vitrified in MS (56.25%) and TS (56.55) methods. After 48 h of culture, the hatching rate for FB vitrified in the MS system (87.21%) was comparable with TS (77.5%) and control (85.3%) groups but significantly higher (P < 0.001) than vitrified EB in MS (43.75%) and TS (36.36%). In conclusion, we showed that a high survival rate of IVP embryos can be achieved by this new in-straw vitrification and warming device (“Sarah”), with hatching rates in vitro comparable with that of control fresh embryos. This method has the potential for use in direct embryo transfer in field conditions.

scholarly journals 97 ASSESSMENT OF VIABILITY OF IN VITRO PRODUCED BOVINE EMBRYOS FOLLOWING VITRIFICATION BY CVM OR SLOW FREEZING WITH ETHYLENE GLYCOL AND TRIPLE TRANSFER

2005 ◽  
Vol 17 (2) ◽  
pp. 199 ◽  
Author(s):  
B. Peachey ◽  
K. Hartwich ◽  
K. Cockrem ◽  
A. Marsh ◽  
A. Pugh ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Survival Rates ◽  
Slow Freezing ◽  
High Survival ◽  
Bovine Embryos ◽  
Embryo Survival ◽  
Frozen Embryos ◽  
Morula Stage ◽  
Fresh Embryos

Vitrification has become the method of choice for the preservation of in vitro derived embryos of a number of species, and several methods of vitrification have been developed. One such method, the cryoLogic vitrification method (CVM) yields high survival rates of warmed embryos (Lindemans W et al. 2004 Reprod. Fertil. Dev. 16, 174 abst). In this study, the post-warm viability of bovine IVP embryos following either vitrification using CVM or slow freezing using ethylene glycol (EG) was compared. In addition, the survival of embryos following triple transfer to synchronized recipients was measured and the embryo (“e”) and recipient (“r”) contributions to embryo survival was determined using the “er” model for embryo survival (McMillan WH et al. 1998 Theriogenology 50, 1053–1070). Bovine IVP methods were those of van Wagtendonk et al. 2004 Reprod. Fertil. Dev. 16, 214 (abst). On day 7 of culture (Day 0 = IVF), Grade 1 and 2 embryos that had reached at least the late morula stage were selected for vitrification (20% DMSO, 20% ethylene glycol) or freezing in 1.5 M ethylene glycol + 0.1 M sucrose (0.5°C/min to −35°C). Following storage in LN2 for at least 24 h the embryos were thawed, the cryoprotectant removed, and the embryos cultured for 72 h in mSOF medium under 5% CO2, 7% O2, 88% N2. The number of hatching embryos was recorded at 24-h intervals. In addition, blastocyst and expanded blastocyst embryos were thawed and immediately transferred nonsurgically to recipients (three embryos of the same grade to each recipient) on Day 7 of a synchronized cycle (Day 0 = heat). The recipients were ultrasound-scanned for the presence of, and number of, fetuses on Days 35 and 62, respectively. The invitro assessment of 148 CVM and 230 EG frozen embryos indicated that more vitrified than EG embryos hatched by 72 h (73% vs. 62%; CVM vs. EG, χ2 = 4.5, P < 0.05). Overall, more Grade 1 embryos hatched than Grade 2 (74% vs. 60%, χ2 = 7.2, P < 0.01). CVM embryos (105) were triple-transferred to 35 recipients, and EG embryos (30) were triple-transferred to 10 recipients. Recipient pregnancy rates at Day 62 were 80% and 70%, respectively. Overall embryo survival was 38.5% (41% for CVM and 30% for EG). The overall calculated “e” and “r” values were 0.39 and 1.0 (“e”: 0.42 and 1.0, and “r”: 0.31 and 1.0, respectively, CVM and EG groups). Survival rates of CVM embryos to Day 62 (41%) were slightly lower than that previously obtained for fresh embryos produced using an identical IVP procedure (44% – van Wagtendonk AM 2004).

114 VITRIFICATION OF BOVINE EMBRYOS IN MEDIUM WITH POLYVINYL ALCOHOL REPLACING BSA

2006 ◽  
Vol 18 (2) ◽  
pp. 165
Author(s):  
D. J. Walker ◽  
G. E. Seidel Jr
Keyword(s):  
Ethylene Glycol ◽  
Polyvinyl Alcohol ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Survival Rates ◽  
Sodium Hyaluronate ◽  
Blastocyst Stage ◽  
Embryo Survival ◽  
Better Than

Embryos vitrified in medium supplemented with 4.25 μg/mL sodium hyaluronate (SH) and 0.1% polyvinyl alcohol (PVA) survived vitrification better than embryos vitrified in medium supplemented with 0.25% FAF-BSA (Walker and Seidel 2005 Reprod. Fert. Dev. 17, 153). The purpose of the present study was to determine if the small amount of SH was beneficial to in vitro survival and to examine the effects of different concentrations of PVA in vitrification solutions. Day 7 blastocysts (n = 360) were produced in vitro with semen from three bulls, two replicates each. Cryoprotectant solutions were prepared in a 2 × 3 factorial combination with two SH concentrations (0 or 4.25 μg/mL) and three PVA concentrations (0.05, 0.1%, or 0.2%). For vitrification, embryos were placed into chemically defined HEPES-buffered medium (HCDM-2) at room temperature (22–24°C) and then transferred to V1 (5 m ethylene glycol in HCDM-2) for 3 min. Next, embryos were placed in a 6 μL drop of V2 (7 m ethylene glycol, 0.5 m galactose, and 18% w/v Ficoll 70 in HCDM-2) for 45 s. During these 45 s, dilution medium (0.5 m galactose in HCDM-2) was aspirated into 0.25-mL straws, followed by the 6 μL drop of V2 plus embryos and a final short column of dilution medium. When 45 s had elapsed, the heat-sealed end of straw was dipped into liquid nitrogen to cover the embryo, and then the remainder of the straw was immersed slowly. Straws were thawed in air for 10 s and then in 37°C water for 20 s. Next, straws were shaken like a clinical thermometer four times to mix columns, and held in 37°C water for 10 min before embryos were expelled, rinsed and cultured in CDM-2 + 5% FCS. At 48 h, embryo survival (as determined by expansion of blastocysts), embryo quality (1 = excellent, 2 = fair, 3 = poor), inner cell mass (ICM) quality (1 = large and compact, 2 = clearly visible, 3 = not discernable) and blastocyst stage (5 = early, 6 = full, 7 = expanded, 8 = hatching, 9 = hatched) were evaluated and replicate averages were analyzed by ANOVA. Neither bull nor SH concentration nor PVA concentration significantly affected any response (P > 0.10). Averaged over PVA concentrations, vitrification of embryos in 0 μg/mL or 4.25 μg/mL SH resulted in similar survival rates (67% vs. 62%, respectively). When averaged over SH concentrations, 0.2% PVA had a numerically higher survival rate of blastocysts as compared to 0.1% or 0.05% (71% vs. 63% and 60%, respectively). The main effects of 0 μg/mL SH and 0.2% PVA also resulted in numerically higher, but nonsignificant improvements in quality score, ICM score and blastocyst stage as compared to the other doses of SH and PVA. Vitrification of Day 7 in vitro-produced bovine blastocysts in medium containing 0.2% PVA in the absence of SH resulted in a subclass mean of 80% embryo survival. Results of this experiment show no benefit of 4.25 μg/mL SH and that 0.2% PVA may be slightly better than 0.05% or 0.1% in terms of embryo survival. Therefore, our results indicate that 0.2% PVA can be used alone as an effective alternative to animal products in this vitrification procedure for in vitro-derived bovine blastocysts.

79RELATIONSHIPS BETWEEN SURVIVAL RATE AND BIRTH WEIGHT IN CLONED KOREAN NATIVE CALVES

2004 ◽  
Vol 16 (2) ◽  
pp. 161
Author(s):  
B.C. Yang ◽  
G.S. Im ◽  
D.H. Kim ◽  
S.K. Lee ◽  
H.S. Park ◽  
...  
Keyword(s):  
Birth Weight ◽  
Survival Rate ◽  
Caesarean Section ◽  
Survival Rates ◽  
Blastocyst Stage ◽  
High Birth Weight ◽  
Gestation Length ◽  
Average Birth Weight ◽  
Fetal Bovine

Cloning of somatic cells has been investigated actively in cattle, but the cloned calves have been characterized by high birth weight and low survival rate. The present study was conducted to investigate the relationships between survival rate and birth weight in cloned and AI calves. The ear skin fibroblasts were obtained from 2- to 3-year-old Korean native cows (Hanwoo) and the cells were cultured in Dulbeccos Modified Eagles medium (DMEM) supplemented with 10% fetal bovine serum (FBS) at 38.5°C, 5% CO2 in air. Bovine oocytes collected from ovaries obtained from a nearby slaughterhouse were cultured in vitro and then enucleated, injected with donor cells and fused, and cultured to produce cloned embryos at the blastocyst stage. Somatic cell cloning and in vitro culture of embryos were performed by the procedures described previously (Im et al., 2001 AJAS 14, 759–764, and Im et al., 2001 AJAS 14, 1260–1266). A total of 580 cloned embryos at blastocyst stage were transferred to 293 recipient cows; 32 female calves (5.5%) were born (2 of them were born dead). Thirty-four (15 female and 19 male ) calves (57.6%) were born from 59 artificially inseminated Korean native cows as control. Fifteen of the 32 cloned calves were delivered by caesarean section. However, all the artificially inseminated cows delivered naturally. Birth weights of 30 live cloned calves averaged 31.08kg (&gt;15kg:3, 20kg:2, 25kg:2, 30kg:5, 35kg:9, 40kg:6, &lt;45kg:3), while those of female AI calves averaged 23.67kg (&gt;15kg:0, 20kg:3, 25kg:6, 30kg:6, 35kg:0, 40kg:0, &lt;45kg:0). After calving, 11 of 30 cloned calves survived for more than 365 days (birth weight of these calves averaged 28.25kg), but 19 of 30 calves died within 175 days and their average birth weight was 32.80kg (650kg). Gestation length of cows that received cloned embryos was 287 (279–295) days on average (excluding the data of calves delivered by caesarean section) and that of cows artificially inseminated was 287 (255–293) days. In conclusion, the birth weight was significantly correlated (P&lt;0.05) with survival rate of cloned calves, and survival rates of calves with extremely high or low birth weights were significantly low. However, there was no relationship between gestation length and survival rate.

22 Vitrification of bovine embryo using antifreeze polyamino acid

2019 ◽  
Vol 31 (1) ◽  
pp. 137
Author(s):  
T. Fujikawa ◽  
Y. Gen ◽  
S.-H. Hyon ◽  
C. Kubota
Keyword(s):  
Ethylene Glycol ◽  
Survival Rates ◽  
Basal Medium ◽  
Blastocyst Stage ◽  
Bovine Embryo ◽  
Bovine Embryos ◽  
Chi Square ◽  
Embryo Survival ◽  
Polyamino Acid

Carboxylated poly-l-lysine (CPLL) is an ampholytic polymer compound and a polyamino acid with a known functional resemblance to antifreeze proteins. We previously reported that CPLL is an effective cryoprotectant for bovine cells, sperm, and slow-frozen embryos. In this study, we investigated CPLL as a cryoprotectant for vitrified bovine embryos. We developed bovine embryos in vitro and vitrified them at the blastocyst stage. Embryos were equilibrated (3min) and vitrified (1min). Vitrified embryos were cryopreserved in LN (Cryotop® device; Kitazato Corp., Tokyo, Japan) for at least 1 week, thawed with a 0.3M sucrose warming solution, and then cultured in a basal medium (Gibco® medium 199, Grand Island, NY, USA; supplemented with 100µM 2-mercaptoethanol, 10% fetal bovine serum, and antibiotics) at 38.5°C in a humidified atmosphere (5% CO2, 5% O2, 90% N2). We evaluated the embryos morphologically for survival and hatched rate at 0, 24, 48, and 72h post-thawing. In control, the equilibration solution (ES) consisted of 7.5% (vol/vol) dimethyl sulfoxide (DMSO) and 7.5% (vol/vol) ethylene glycol, and the vitrification solution (VS) consisted of 16.5% (vol/vol) DMSO and 16.5% (vol/vol) ethylene glycol and 0.5M sucrose. In this study, CPLL was added to ES and VS at various concentrations instead of DMSO. The CPLL was added at 16.5, 11.0, 5.5, and 2.2% (wt/vol) to VS; respectively, these solutions were named P16.5, P11.0, P5.5, and P2.2. The ES was used 45% CPLL of VS each. Embryos underwent the above procedure concurrently, with testing replicated at least 3 times. We evaluated 88, 34, 38, 44, and 28 embryos with each solution (control, P16.5, P11.0, P5.5, and P2.2, respectively). Results were analysed statistically with a chi-square test and residual analysis, regarding P&lt;0.05 as significant. Survival rates were significantly greater in P11.0 at 24h post-thawing (55.7% v. 89.5%; P&lt;0.05) and in P11.0 and P5.5 at 48h post-thawing (47.7% v. 78.9% and 47.7% v. 79.5%, respectively; P&lt;0.05) relative to controls but showed no significant differences at 0h post-thawing. Hatched rates were significantly greater in P11.0 and P5.5 through 72h post-thawing relative to controls (44.7% v. 22.7% and 52.3% v. 22.7%, respectively; P&lt;0.05). The CPLL improved post-thawing embryo survival and hatched rates when applied during vitrification, thus demonstrating cryoprotective effectiveness. We conclude that CPLL acts as a low-toxicity cryoprotectant for vitrified bovine embryos, and our results are consistent with previous reports of protective CPLL effects for cells and cell membranes.

125 IN VITRO-PRODUCED BOVINE EMBRYOS VITRIFIED IN GLASS CAPILLARIES USING TCM-199 OR DULBECCO'S PHOSPHATE-BUFFERED SALINE AS VITRIFICATION-WARMING MEDIA

2007 ◽  
Vol 19 (1) ◽  
pp. 180 ◽  
Author(s):  
N. Mucci ◽  
G. G. Kaiser ◽  
G. Rios ◽  
R. H. Alberio ◽  
L. B. Ferré ◽  
...  
Keyword(s):  
Survival Rate ◽  
Control Group ◽  
Internal Diameter ◽  
Hatching Rate ◽  
External Diameter ◽  
Low Oxygen ◽  
Embryo Survival ◽  
Glass Capillaries ◽  
Phosphate Buffered Saline

In previous studies (unpublished data) we observed that the replacement of open pulled straws (OPS) with glass capillaries (GC) did not affect the embryo survival rate after vitrification–warming. The aim of this work was to evaluate the post-Cryopreservation survival rate of in vitro-produced bovine blastocysts (B) and expanded blastocysts (eB) using Dulbecco&apos;s phosphate-buffered saline (PBS) or TCM-199 (TCM; Sigma-Aldrich, St Louis, MO, USA) as holding medium during vitrification and warming in glass capillaries. Cumulus–oocyte complexes were in vitro-matured and fertilized as previously described (Mucci et al. 2006 Theriogenology 65, 1551–1562), and cultured in 4 well plates in groups of 50 in 400-�L drops in serum-free CR1aa under low oxygen condition. Grade B1, B2, and eB were selected at Day 7 post-insemination and allocated to 3 groups: vitrification in TCM, vitrification in PBS, and control (without vitrification). Vitrification and warming were performed according to Vajta et al. (1998, Mol. Reprod. Dev. 51, 53–58), replacing OPS with GC (Tecnon Argentina S.A., Buenos Aires, Argentina); 75 mM length, 1.4 mM internal diameter, 1.6 mM external diameter). Briefly, B and eB were incubated in 1.78 M ethylene glycol (EG) and 1.3 M dimethyl sulfoxide (DMSO) in TCM or PBS supplemented with 20% estrous cow serum (ECS) for 3 min. Embryos were then transferred for 25 s to TCM or PBS supplemented with 3.56 M EG, 2.6 M DMSO, 0.5 M sucrose, and 20% ECS (vitrification solution: VS). Loading of embryos (2 per capillary) was performed by touching a 1-�L drop of VS with the capillary. After this, each capillary was immediately submerged into and stored in liquid nitrogen. Warming was performed by placing the capillary tip directly into TCM or PBS supplemented with 0.25 M sucrose for 5 min. Embryos were then transferred to TCM or PBS containing 0.15 M sucrose and 20% ECS for 1 min. After warming, embryos were cultured for 72 h in CR1aa + 5% ECS to evaluate embryo survival (hatching rate). Data was analyzed using the CATMOD procedure (SAS Institute, Inc., Cary, NC, USA). No interaction was found between holding media and embryo stage. Vitrified-warmed embryos had a significantly lower hatching rate compared with the control group (P &lt; 0.05), whereas no differences were found between TCM and PBS. Expanded blastocysts had a higher hatching rate than blastocysts (P &lt; 0.05). In conclusion, TCM can be replaced with PBS for its use in vitrification procedures. This protocol modification allows a simplified use of this technique in field conditions.

149 IN VITRO BOVINE EMBRYOS FROZEN BY DIRECT TRANSFER METHOD WITH ETHYLENE GLYCOL

2015 ◽  
Vol 27 (1) ◽  
pp. 166
Author(s):  
S. H. Kizil ◽  
M. Satilmis ◽  
N. Akyol ◽  
T. Karasahin
Keyword(s):  
Ethylene Glycol ◽  
Survival Rates ◽  
Hatching Rate ◽  
Direct Transfer ◽  
Embryo Freezing ◽  
Frozen Embryos ◽  
Transfer Method ◽  
Phosphate Buffered Saline ◽  
In Vitro Survival

The objective of this study was to search for capability of freezing by ethylene glycol direct transfer method of in vitro-produced cattle embryos. Fifty-six in vitro-produced good-quality cow embryos were frozen by direct transfer method with ethylene glycol in this study. Cattle ovaries were collected from a slaughterhouse and oocytes were aspirated from follicles with 2 to 8 mm diameters. Then oocytes were let for maturation of 20 to 22 h in 100-μL microdroplets of TCM-199 with 0.1 mM β-mercaptoethanol and 20% FCS. After 5 to 6 h of fertilization in Bracket Oliphant (BO), they were cultured for 7 days in 100 µL of CR1aa medium with 5% FCS under 5% CO2, 98% relative humidity, and 38.5°C in a CO2 incubator. Embryos were equilibrated for 15 min in room temperature in 1.8 M ethylene glycol + 0.1 M sucrose in Dulbecco's phosphate buffered saline (D-PBS) supplemented with 20% FCS. Embryos were then loaded individually into a 0.25-mL straw and placed directly into a cooling chamber of a programmable freezer with methyl alcohol precooled to –7°C. After 2 min, the straw was seeded and maintained at –7°C for 8 min more. Then it was cooled to –30°C at 0.3°C min–1 before plunging into liquid nitrogen. The frozen embryos were thawed by allowing the straw to stand in air for 5 to 6 s and then immersing them in a 30°C water bath for 10 s. After thawing, embryos were transferred into TCM-199 + 0.1 mM β-mercaptoethanol + 20% FCS medium to check in vitro survival rates at 48 h post-thawing. The re-expansion and hatching rate of blastocysts was 64.28% (36 blastocysts). This result indicated that ethylene glycol can be used effectively for cow embryo freezing as a suitable cryoprotectant for direct transfer method.

24 Survival rates of vitrified biopsied bovine in vitro-produced blastocysts using the VitTrans device

2019 ◽  
Vol 31 (1) ◽  
pp. 138
Author(s):  
N. González ◽  
J. Scherzer ◽  
M. Reichenbach ◽  
C. Otzdorff ◽  
H. Zerbe
Keyword(s):  
Ethylene Glycol ◽  
Dimethyl Sulfoxide ◽  
Embryo Transfer ◽  
Zona Pellucida ◽  
Survival Rates ◽  
Petri Dish ◽  
Blastocyst Stage ◽  
Control Group ◽  
Embryo Survival

In breeding programs, the application of a vitrification method suitable for direct transfer of biopsied embryos can increase the genetic improvement of cattle and help reduce the costs of embryo transfer. The aim of this study was to determine the in vitro survival of biopsied vitrified blastocysts using the new VitTrans device (Morató and Mogas 2014 Cryobiology 68, 288-293), a 1-step in-straw warming system. Immature bovine oocytes were in vitro matured, fertilized, and cultured to the blastocyst stage. A total of 110 grade 1 blastocysts (IETS codes 6 and 7) were randomly allocated to 2 groups: (1) biopsy (n=49) and (2) without biopsy, or control (n=61). Blastocysts were biopsied using a microblade mounted on a micromanipulator. A small portion of the trophoblast, approximately 15%, was cut off and a significant part of the zona pellucida was sliced away. Both groups were then vitrified using the VitTrans device. For vitrification, all blastocysts were exposed to an equilibration medium with 7.5% ethylene glycol+7.5% dimethyl sulfoxide in holding medium (HM) consisting of TCM-199 with 20% FCS, moved into a drop with 16.5% ethylene glycol+16.5% dimethyl sulfoxide+0.5M sucrose in HM, and then placed in a microdroplet on the VitTrans. The VitTrans was plunged into LN and covered with a 0.5-mL straw. For warming, the protective cover was removed from the VitTrans while still submerged in LN. Subsequently, a new 0.5-mL plastic embryo transfer straw was placed on the VitTrans while flushing the warming solution (0.3mL of 0.5M sucrose in HM at 45°C) with a syringe through the lumen of the device. By entering the warming solution into the VitTrans device, the embryo is flushed inside the plastic straw. The straw containing the embryo can then be readily used for transfer after the VitTrans is removed. To recover the embryo in the laboratory, the content of the straw was put into a Petri dish and blastocysts were placed in the culture medium and incubated at 38.5°C in 5% CO2 and 5% O2 in air. Morphology and re-expansion were evaluated 24h post-warming. The embryo survival rate was defined as the ratio of blastocysts that were able to re-expand with regards to the total number of warmed blastocysts. Due to the attachment of embryos inside the straw, a total of 18 embryos were lost during recovery (12 from the biopsied group and 6 from the nonbiopsied group). The ratio of re-expanded blastocysts from the recovered embryos was 40% in the biopsy group and 61% in the control group. In conclusion, vitrification using the VitTrans device showed good results with intact embryos compared with biopsied embryos. In addition, biopsied embryos had a tendency to adhere to the inside of the straw, which is probably due to the damage or loss of the zona pellucida. Additional research is required to minimize the loss of embryos.

scholarly journals Vitrification Effects on the Transcriptome of in vivo-Derived Porcine Morulae

2021 ◽  
Vol 8 ◽  
Author(s):  
Cristina Cuello ◽  
Cristina A. Martinez ◽  
Josep M. Cambra ◽  
Alejandro González-Plaza ◽  
Inmaculada Parrilla ◽  
...  
Keyword(s):  
Gene Expression ◽  
Metabolic Pathways ◽  
Survival Rates ◽  
Gene Expression Pattern ◽  
Control Group ◽  
High Survival ◽  
Embryo Survival ◽  
Developmental Potential

Despite the reported promising farrowing rates after non-surgical and surgical transfers of vitrified porcine morulae and blastocysts produced in vivo (range: 70–75%), the pregnancy loss is 5–15 fold higher with vitrified than with fresh embryos. The present study aimed to investigate whether vitrification affects the transcriptome of porcine morulae, using microarrays and RT-qPCR validation. Morulae were obtained surgically from weaned sows (n = 13) on day 6 (day 0 = estrus onset). A total of 60 morulae were vitrified (treatment group). After 1 week of storage, the vitrified morulae were warmed. Vitrified-warmed and non-vitrified fresh morulae (control; n = 40) were cultured for 24 h to assess embryo survival by stereomicroscopy after. A total of 30 vitrified/warmed embryos that were deemed viable and 30 fresh control embryos (three pools of 10 for each experimental group) were selected for microarray analysis. Gene expression was assessed with a GeneChip® Porcine Genome Array (Affymetrix). An ANOVA analysis p-unadjusted &lt;0.05 and a fold change cut-off of ±1.5 were set to identify differentially expressed genes (DEGs). Data analysis and biological interpretation were performed using the Partek Genomic Suite 7.0 software. The survival rate of morulae after vitrification and warming (92.0 ± 8.3%) was similar to that of the control (100%). A total of 233 DEGs were identified in vitrified morulae (38 upregulated and 195 downregulated), compared to the control group. Nine pathways were significantly modified. Go-enrichment analysis revealed that DEGs were mainly related to the Biological Process functional group. Up-regulated DEGs were involved in glycosaminoglycan degradation, metabolic pathways and tryptophan metabolism KEGG pathways. The pathways related to the down-regulated DEGs were glycolysis/gluconeogenesis, protein export and fatty acid elongation. The disruption of metabolic pathways in morulae could be related to impaired embryo quality and developmental potential, despite the relatively high survival rates after warming observed in vitro. In conclusion, vitrification altered the gene expression pattern of porcine morulae produced in vivo, generating alterations in the transcriptome that may interfere with subsequent embryo development and pregnancy after embryo transfer.

Effects of vitrification on blastomere viability and cytoskeletal integrity in mouse embryos

Zygote ◽  
2016 ◽  
Vol 25 (1) ◽  
pp. 75-84 ◽  
Author(s):  
Zenon Oikonomou ◽  
Katerina Chatzimeletiou ◽  
Antonia Sioga ◽  
Louisa Oikonomou ◽  
Basil C. Tarlatzis ◽  
...  
Keyword(s):  
Survival Rates ◽  
Multivariable Analysis ◽  
Blastocyst Stage ◽  
Mouse Embryos ◽  
High Survival ◽  
Fluorescent Markers ◽  
Morula Stage ◽  
Confocal Scanning ◽  
Fresh Embryos

SummaryVitrification is widely used to cryopreserve supernumerary embryos following in vitro fertilization (IVF). The mouse model was used to investigate the effects of vitrification on blastomere viability, using viability markers, and on the cytoskeleton, by analysing spindle/chromosome configurations, using confocal scanning microscopy. Ninety cleavage and morula stage dimethyl sulphoxide (DMSO)/EG vitrified mouse embryos were either processed immediately following warming for viability assessment by labelling with the fluorescent markers carboxyfluorescein-diacetate succinimidylester (CFSE) and propidium iodide (PI) or were cultured to the blastocyst stage and immunostained with α-tubulin antibody to visualize microtubules and DAPI or PI to visualize DNA. Sixty-five fresh embryos were also used as the control. Vitrified embryos showed high survival rates following warming, but they had a higher incidence of damaged blastomeres compared with fresh embryos. Most mitotic spindles examined in all groups were normal, but multivariable analysis revealed that the proportion of abnormal spindles was significantly higher in vitrified/warmed embryos (P < 0.05). This study is the first to examine the immediate effects of vitrification on blastomere viability, using fluorescent markers and shows that although vitrification results in a higher incidence of damaged blastomeres, vitrified embryos may compensate for this limited number of damaged/abnormal cells, as development to the blastocyst stage was not compromised.

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