60 IMPROVEMENT IN EFFICIENCY AND QUALITY OF CLONED AND PARTHENOGENETIC PORCINE EMBRYOS BY AMINO ACIDS

2007 ◽  
Vol 19 (1) ◽  
pp. 147
Author(s):  
H. T. Lee ◽  
J. M. Jang ◽  
S. H. Lee ◽  
M. K. Gupta
Keyword(s):  
Amino Acids ◽  
Culture Media ◽  
Cell Number ◽  
Control Group ◽  
In Vitro Production ◽  
Cleavage Rate ◽  
Fetal Fibroblasts ◽  
Blastocyst Rate

In vitro production of cloned porcine embryos by somatic cell nuclear transfer (SCNT) has become routine in several laboratories but the efficiency and quality of the resultant blastocysts remains sub-optimal. Cloned porcine blastocysts show low cell number, high fragmentation rate, and apoptosis which results in lower pregnancy rates upon embryo transfer. Earlier we reported that supplementation of culture media with amino acids benefit pre-implantation embryo development of in vivo- as well as in vitro-fertilized porcine embryos (Koo et al. 1997 Theriogenology 48, 791–802). This study evaluated how exogenous amino acids could affect pre-implantation development and quality of cloned or parthenogenetic porcine embryos. The effects of commercially available amino acids, referred to as Eagle's non-essential amino acids (NEAA), added or not added (control) to NCSU23 medium containing fatty acid-free BSA were studied. Oocytes recovered from abattoir-derived prepubertal porcine ovaries were matured in vitro and parthenogenetically activated (PA) or nuclear-transferred with fetal fibroblasts (SCNT), as described earlier (Uhm et al. 2000 Mol. Reprod. Dev. 57, 331–337). At 168 h post-activation, blastocysts were harvested for assessment of embryo quality by TUNEL labeling, Hoechst 33342 staining, and gene expression analysis. Results showed that, in the PA group, the cleavage rate was not affected by the supplementation of NEAA. However, the blastocyst rate was significantly improved when NEAA was present in the medium compared to that of the control group (38.9 ± 0.3 vs. 27.5 ± 0.3%, respectively) throughout the culture period. The supplementation during the pre-compaction period alone gave better results than during the post-compaction period alone (59.5 ± 0.9 vs. 33.4 ± 0.3%, respectively). In the SCNT group, however, both cleavage (73.6 ± 0.2 vs. 64.2 ± 0.4%) and blastocyst rate (18.7 ± 0.2 vs. 13.8 ± 0.3%) were improved by NEAA supplementation. Furthermore, these blastocysts had higher hatching ability (30.0 ± 1.8 vs. 14.6 ± 4.9%) than those of control group (P < 0.05). Supplementation of NEAA also increased the mean nuclei number of PA-derived (76.1 ± 4.9 vs. 66.5 ± 3.3) as well as SCNT-derived (43.1 ± 2.6 vs. 31.8 ± 1.9) blastocysts and reduced the time during which blastocysts formed. TUNEL assay revealed that incidence of nuclear fragmentation and apotosis was reduced by NEAA. Real-time qRT-PCR for Bax and Bcl-XL transcripts revealed that the relative abundance of Bax was reduced while that of Bcl-XL was increased. These effects were more pronounced when NEAA was present during the pre-compaction period alone. Thus, our data suggest that NEAA improves the yield and quality of cloned porcine embryos by enhancing blastocyst expansion and positively modulating the total cell number and apoptosis. These data may have implications for understanding the nutritional needs of cloned porcine embryos produced in vitro and for optimizing the composition of culture media to support their development. This work was supported by the Research Project on the Production of Bio-Organs (No. 200503030201), Ministry of Agriculture and Forestry, Republic of Korea.

scholarly journals 63 IMPROVED IN VITRO DEVELOPMENT OF PORCINE EMBRYOS PRODUCED BY NUCLEAR TRANSFER, IVF AND PARTHENOGENESIS

2005 ◽  
Vol 17 (2) ◽  
pp. 181 ◽  
Author(s):  
D. Sage ◽  
P. Hassel ◽  
B. Petersen ◽  
W. Mysegades ◽  
P. Westermann ◽  
...  
Keyword(s):  
Nuclear Transfer ◽  
Culture Media ◽  
Cumulus Cells ◽  
Cell Number ◽  
Foster Mother ◽  
Chi Square ◽  
Fetal Fibroblasts ◽  
Blastocyst Rate ◽  
Parthenogenetic Embryos

Porcine nuclear transfer (NT) is an inefficient process and it is necessary to use as many as 120 NT embryos for each foster mother to obtain small litters of live piglets. In these experiments, we evaluated the effects of culture atmosphere and medium on the development of NT embryos by monitoring blastocyst rate and cell number of Day 6 blastocysts. Age matched IVF and parthenogenetic embryos were also evaluated for comparison. For all experiments a pool of oocytes was aspirated from ovaries collected in a local abattoir. Following aspiration, oocytes were allowed to mature for 40 h in North Carolina State University (NCSU)-37 medium (supplemented with cAMP and hCG/eCG for the first 22 h). After removal of the cumulus cells, denuded oocytes with polar bodies were selected for NT, enucleated, fused with fetal fibroblasts, and sequentially activated electrically and chemically by 3 h of treatment with 6-dimethylaminopurine (6-DMAP). A second group of oocytes from the same denuded pool were maintained in TL-HEPES medium and activated in parallel with the NT group to produce parthenogenetic embryos. A third group was fertilized with frozen-thawed epididymal semen and co-cultured for ∼12 h to give IVF embryos. All three treatment groups were subdivided into a control subgroup and an experimental subgroup. In the first experiment, we compared the effects of atmosphere (20% vs. 5% oxygen) on in vitro embryonic development in NCSU-23 medium. In the second experiment, we used only the 5% oxygen concentration and compared different culture media. One subgroup was maintained in standard NCSU-23 medium and the second subgroup was cultured in a two-step system for the first 58 h in modified NCSU-23 (without glucose but supplemented with 2.0 mM lactate and 0.2 mM pyruvate), followed by addition of glucose to give a final concentration of 5.55 mM. Data were statistically analyzed by analysis of variance and chi square test. Blastocyst rate and mean cell number in all three embryo groups were improved under 5% oxygen. The most dramatic effect was observed in the NT group, in which the blastocyst rate increased significantly (P < 0.001) from 6.7% ± 5.9 (n = 279) to 19.6% ± 8.9 (n = 250) and mean cell number increased from 17.7 ± 12.1 to 25.8 ± 10.3 cells per blastocyst. With 5% oxygen there was also an increase of blastocyst rates and mean cell numbers in both IVF and parthenogenetic groups. In the second experiment, blastocyst rate for NT embryos increased significantly (P < 0.05) from 21.8% ± 7.6 (n = 242) in conventional NCSU-23 to 31.5% ± 11.0 (n = 271) in the modified system whereas there was almost no difference in the mean cell number of both groups (29.2 ± 4.3 vs. 31.5 ± 5.3). In the groups of IVF and parthenogenetic embryos no difference was found. These results indicate that both the reduced oxygen and the modified culture medium are important for pre-implantation development of porcine nuclear transfer embryos.

286 INFLUENCE OF REVERSIBLE MEIOSIS INHIBITION ON SWINE EMBRYOS PRODUCED BY IN VITRO FERTILIZATION AND PATHENOGENETIC ACTIVATION

2006 ◽  
Vol 18 (2) ◽  
pp. 250
Author(s):  
M. G. Marques ◽  
A. B. Nascimento ◽  
V. P. Oliveira ◽  
A. R. S. Coutinho ◽  
M. E. O. A. Assumpção ◽  
...  
Keyword(s):  
Culture Medium ◽  
Cell Number ◽  
Control Group ◽  
Cleavage Rate ◽  
Vitro Fertilization ◽  
Electric Pulses ◽  
Cell Numbers ◽  
Blastocyst Rate ◽  
And Control

The present work evaluated the reversible meiosis inhibition effect on the development of swine embryos produced by in vitro fertilization (IVF) or parthenogenetic activation (PA). The efficiency of PZM3 and NCSU23 embryo culture media was also evaluated. Oocytes from ovaries collected at a slaughterhouse were subjected to IVM in two different groups: CHX (cycloheximide 5 µM for 10 h) and control, both with TCM-199 + 3.05 mM glucose + 0.91 mM sodium pyruvate + 10% porcine follicular fluid (pFF) + 0.57 mM cystein + 10 ng epidermal growth factor (EGF)/mL + 10 IU eCG/mL + 10 IU hCG/mL for the initial 22 h. In the remaining period (20 h for CHX and 22 h for control), medium without hormones was utilized. After IVM, oocytes were denuded and fertilized for 6 h (IFV) or the matured oocytes were submitted to activation by electric pulses (PA) (2 DC of 1.5 kV/cm for 30 µs), incubated for 1 h in culture medium with 10 μM of CHX, and again submitted to the same electric pulses for 60 µs. Embryo development was evaluated by cleavage rate on Day 3 and blastocyst rate and blastocyst cell number on Day 7 of culture. Cleavage and blastocyst rates were analyzed by the equality-of-two-ratios test and cell number by the Kruskal-Wallis and Mann-Whitney tests (P < 0.05). In relation to IVF, the PZM3 medium was more efficient than NCSU23 for cleavage rate in the CHX group (PZM3: 68.4%, NCSU23: 44.4%) and had a better blastocyst rate in the control group (PZM3: 13.4%, NCSU23: 5.6%). With reference to PA, NCSU23 presented better cleavage and blastocyst rates than PZM3 in the CHX group (NCSU23: 89.5%, PZM3: 78.5% and NCSU23: 20.4%, PZM3: 13.0%, respectively). In the control group, only the NCSU23 blastocyst rate was higher than that for PZM3 (NCSU23: 22.5%, PZM3: 10.8%). No culture medium effect on cell number mean of IVF and PA blastocysts was observed. Maturation block improved cleavage rates in IVF groups cultured with PZM3 (68.4% and 50.6%, respectively, for CHX and control) and in PA groups cultured with NCSU23 (89.5% and 80.3%, respectively, for CHX and control), but no improvement of blastocyst rates in both groups (IVF and PA) was verified. Table 1 below shows that maturation block decreased the IVF and increased the PA blastocyst cell numbers. As older oocytes are more effectively activated, oocytes blocked with CHX achieved the maturation stage faster than the control group, therefore resulting in high-quality PA blastocysts. In conclusion, PZM3 was more efficient for IVF embryo production in contrast to NCSU23, whereas NCSU23 can be indicated for PA embryo production. Moreover, maturation blockage with CHX influenced blastocyst cell number, decreasing in IVF embryos and increasing in PA embryos. Table 1. Mean (±SD) of blastocyst cell numbers for IVF or PA groups after in vitro maturation without (control) or with cycloheximide (CHX) and cultured in NCSU23 or PZM3 medium This work was supported by FAPESP 02/10747–1.

113 EFFECT OF PLANT PROTEIN ON DEVELOPMENT AND QUALITY OF CULTURED IN VITRO PORCINE ZYGOTES

2009 ◽  
Vol 21 (1) ◽  
pp. 157 ◽  
Author(s):  
B. Gajda ◽  
I. Grad ◽  
Z. Smorag
Keyword(s):  
Serum Albumin ◽  
Culture Media ◽  
Quality Criteria ◽  
Cell Number ◽  
Developmental Competence ◽  
Plant Protein ◽  
Control Group ◽  
Group 1

Basic culture media are usually supplemented with serum albumin or serum, which contain amino acids that play an important role as energy sources, osmoregulators, and pH stabilizers. However, the presence of undefined serum in culture media introduces a variation from batch to batch and increases viral or prion contamination risk. The aim of the present study was to investigate the possibility of using plant protein substitute (PP) in place of bovine serum albumin (BSA) during in vitro culture of porcine zygotes. The PP is a mixture of several plant proteins and soya lecithin prepared using a high pressure homogenization process. The experiment was done on pig zygotes obtained surgically from superovulated gilts at 24–26 h after insemination. Morphologically normal zygotes were cultured in vitro in 5% CO2 in air at 39° in NCSU-23 medium supplemented with: 0.002 g mL–1 (group 1), 0.004 g mL–1 (group 2), 0.008 g mL–1 (group 3) PP or 0.004 g mL–1 BSA (control group). Embryo quality criteria were developmental competence (cleavage, morula and blastocyst rates), total cell number per blastocyst and degree of apoptosis as assessed by TUNEL method. Results were analyzed by Chi-square test. There were no differences in cleavage rates on Day 2 between zygotes cultured in NCSU-23 medium supplemented with PP (86.0, 88.0, 84.8; group 1 to 3, respectively) and BSA (91.0%, control group). Culture with 0.008 g mL–1 PP increased morula (85.7%) and blastocyst (69.2%) production as compared with control (75.0% and 56.3%, respectively; P < 0.05) and 0.002 g mL–1 PP (79.5% and 51.8%, respectively; P < 0.05). The mean number of cells in Day 7 blastocysts cultured in NCSU-23 medium + 0.004 g mL–1 BSA was lower (P < 0.05) than in NCSU-23 + 0.004 g mL–1 PP (39.1 v. 43.7, respectively). The blastocysts cultured in NCSU-23 medium + 0.002 g mL–1 PP had higher average number of apoptotic nuclei (13.0) as compared with the control (6.5) and 0.004 g mL–1 PP (6.9). In conclusion, this study suggest the positive effect of PP on development in vitro of porcine zygotes to the morula/blastocyst stage. However, further studies are required to determine the quality of the embryos cultured with PP. This study was supported by Scientific Net of Animal Reproduction Biotechnology.

scholarly journals Effect of insulin–transferrin–selenium (ITS) and l-ascorbic acid (AA) during in vitro maturation on in vitro bovine embryo development

Zygote ◽  
2016 ◽  
Vol 24 (6) ◽  
pp. 890-899 ◽  
Author(s):  
A.L.S. Guimarães ◽  
S.A. Pereira ◽  
M. N. Diógenes ◽  
M.A.N. Dode
Keyword(s):  
Ascorbic Acid ◽  
Cell Number ◽  
Total Cell ◽  
Control Group ◽  
Bovine Embryo ◽  
Total Cell Number ◽  
Embryo Production ◽  
Embryo Size ◽  
Blastocyst Rate

SummaryThe aim of this study was to evaluate the effect of adding a combination of insulin, transferrin and selenium (ITS) and l-ascorbic acid (AA) during in vitro maturation (IVM) and in vitro culture (IVC) on in vitro embryo production. To verify the effect of the supplements, cleavage and blastocyst rates, embryo size and total cell number were performed. Embryonic development data, embryo size categorization and kinetics of maturation were analyzed by chi-squared test, while the total cell number was analyzed by a Kruskal–Wallis test (P < 0.05). When ITS was present during IVM, IVC or the entire culture, all treatments had a cleavage and blastocyst rates and embryo quality, similar to those of the control group (P < 0.05). Supplementation of IVM medium with ITS and AA for 12 h or 24 h showed that the last 12 h increased embryo production (51.6%; n = 220) on D7 compared with the control (39.5%; n = 213). However, no improvement was observed in blastocyst rate when less competent oocytes, obtained from 1–3 mm follicles, were exposed to ITS + AA for the last 12 h of IVM, with a blastocyst rate of 14.9% (n = 47) compared with 61.0% (n = 141) in the control group. The results suggest that the addition of ITS alone did not affect embryo production; however, when combined with AA in the last 12 h of maturation, there was improvement in the quantity and quality of embryos produced. Furthermore, the use of ITS and AA during IVM did not improve the competence of oocytes obtained from small follicles.

scholarly journals Resveratrol-supplemented holding or re-culture media improves viability of fresh or vitrified-warmed in vitro-derived bovine embryos

2021 ◽  
Vol 10 (14) ◽  
pp. e367101422097
Author(s):  
Arianny Rafaela Neto Silva ◽  
Thaisa Campos Marques ◽  
Elisa Caroline Silva Santos ◽  
Tiago Omar Diesel ◽  
Isabelle Matos Macedo ◽  
...  
Keyword(s):  
Culture Media ◽  
Cell Number ◽  
Time Dependent ◽  
Expansion Rate ◽  
Ros Generation ◽  
Hatching Rate ◽  
Protective Effects ◽  
Bovine Embryos ◽  
In Vitro Production

The effect of resveratrol supplementation on fresh (E1) or vitrified/warmed (E2) in vitro produced bovine embryos was investigated by evaluating the time-dependent response. After in vitro production, resveratrol (0.5 µM) was added to the incubation media and after two incubation periods with or without resveratrol, blastocysts were re-cultured for 24h. The rates of re-expansion, hatching, total cell number (TCN), apoptotic cells (ACN), reactive oxygen species (ROS) and intracellular glutathione (GSH) content were evaluated. For E1, the re-expansion rate differed at 6 and 10h within and between treatments (P<0.05), as did the re-expansion rate after 24h (P<0.01). The hatching rate increased after 10h with resveratrol (P<0.01) with differences within (P<0.05), but not between treatments after 24h of re-cultivation. At E2, hatching rate differed between treatments at 24h (P<0.01), with higher TCN in resveratrol-treated blastocysts after 10h (P<0.01). Resveratrol supplementation reduced ROS generation in E1 and E2 after 10h of incubation and increased GSH content (P<0.01). These results indicate that supplementation of holding re-cultivation medium with resveratrol for treatment of fresh or vitrified/warmed in vitro produced bovine embryos has a positive and time-dependent effect. The reduction of ROS content, the increase of GSH and the anti-apoptotic ability of resveratrol are responsible for its protective effects, allowing an extension of embryo storage time before transfer to recipients.

155 QUALITY OF PORCINE EMBRYO PRODUCED IN TWO EMBRYO CULTURE MEDIA AS ASSESSED BY TOTAL CELL NUMBER AND TIME COURSE OF BLASTOCYST HATCHING

2006 ◽  
Vol 18 (2) ◽  
pp. 185 ◽  
Author(s):  
Y. Agca ◽  
H. Men ◽  
S. F. Mullen ◽  
L. K. Riley ◽  
R. S. Prather ◽  
...  
Keyword(s):  
Embryo Culture ◽  
Time Course ◽  
Culture Media ◽  
Cell Number ◽  
Total Cell ◽  
Total Cell Number ◽  
Blastocyst Hatching ◽  
Hatching Rates

The ability to produce porcine embryos of good quality will have a significant impact on a number of porcine assisted reproductive technologies, such as cloning, intracytoplasmic sperm injection, and embryo cryopreservation. However, porcine embryos resulting from current serum-free embryo culture systems differ significantly both structurally and functionally from those derived in vivo (Wang et al. 1999 Mol. Reprod. Dev. 53, 99-107). In this experiment, the quality of porcine embryos produced by North Carolina State University (NCSU)-23 medium (Petters and Wells 1993 J. Reprod. Fertil. Suppl. 1993, 48, 61-73) and porcine zygote medium (PZM)-1 (Yoshioka et al. 2002 Biol. Reprod. 66, 112-119) were compared by assessing the total cell number and the time course of in vitro blastocyst hatching. Porcine embryos were produced by in vitro maturation and fertilization using serum-free systems. After fertilization, presumptive zygotes were randomly allocated to either PZM-1 or NCSU-23 for subsequent development. On Day 4 of culture, the embryo culture media were supplemented with 10% fetal bovine serum (FBS). Day 6 blastocysts from each group were counted and the blastocysts were subsequently fixed in 4% formalin for counting the total cell number. The cell number in each embryo was determined by counting the nuclei after staining with bisbenzimide (Hoechst 33342). To assess the hatching ability of blastocysts, Day 6 blastocysts were cultured until Day 9 and hatched blastocysts were counted daily. Day 6 blastocyst rates (ratio of blastocysts to oocytes) and total cell number count were replicated three times. The time course of blastocyst hatching experiment was repeated four times. The data were analyzed using a chi-square test, Fisher's exact test, or Student's t-test. The blastocyst rate from culture in PZM-3 was 19.4 � 0.96% (mean � SEM), which was similar to that (16.7 � 3.2%) resulting from culture in NCSU-23 (P > 0.05). However, the total cell number in Day 6 blastocysts cultured in PZM-3 was significantly higher than for blastocysts cultured in NCSU-23 (57 � 3.1 vs. 46 � 1.7; P < 0.01). The total hatching rates (ratio of hatched blastocysts to total blastocysts) by Day 9 were similar between the two culture systems (50.1 � 9.1% vs. 50.7 � 4.1%; P > 0.05). However, on Day 6, 2.1% of blastocysts from PZM-3 culture hatched whereas no blastocysts from NCSU-23 culture hatched. The cumulative hatching rates from PZM-3 culture on Day 7 were significantly higher than those from NCSU-23 culture (15.1 � 3.8% vs. 2.6 � 1.1%; P < 0.01). In conclusion, these data suggest that blastocysts produced in PZM-3 medium have better quality than blastocysts produced in the NCSU-23 culture system as assessed by the total cell number and the time course of blastocyst hatching. This project was supported by a grant from the National Institutes of Health (U42 RR 018877).

298 SPERM CAPACITATED WITH CALCIUM IONOPHORE AS A VECTOR FOR IN VITRO PRODUCTION OF BOVINE TRANSGENIC EMBRYOS

2006 ◽  
Vol 18 (2) ◽  
pp. 256
Author(s):  
R. Simões ◽  
M. P. Milazzotto ◽  
C. Yamada ◽  
W. B. Feitosa ◽  
A. R. S. Coutinho ◽  
...  
Keyword(s):  
Cell Monolayer ◽  
Calcium Ionophore ◽  
Control Group ◽  
Sperm Cells ◽  
In Vitro Production ◽  
Successful Technique ◽  
Blastocyst Rate ◽  
Transgenic Embryos ◽  
Vitro Production

Production of transgenic mouse embryos by microinjection is a well established and successful technique. However, when microinjection protocols were used for bovine, the amount of the oocyte lipid content did not allow the production of bovine transgenic embryos. Sperm-mediated gene transfer (SMGT) is an alternative for this species because it has lower cost and does not require microinjection handling. One of the procedures to introduce exogen DNA into oocytes is by means of sperm capacitated with calcium ionophore (CaI). The aim of this work was to evaluate different CaI concentrations ([CaI]), sperm incubation times with CaI (tCa), and incubation times of sperm capacitated with DNA (tDNA) (EYFP; Clontech, Palo Alta, CA, USA) to establish a satisfactory method for IVP of bovine transgenic embryos. Slaughterhouse oocytes with compact cumulus and uniform ooplasm were in vitro maturated in TCM-199 medium + 10% FCS + FSH + hCG + estradiol (E2) + piruvate + gentamicin under 5% CO2 in air, at 39�C and high humidified atmosphere for 24 h. Semen was thawed in a water bath at 37�C for 30 s and separated by Percoll gradient (45/90%) at 600g for 30 min. After this procedure, sperm cells were washed in TALP-semen medium by centrifugation at 200g for 5 min at room temperature. Supernatant was removed and capacitation (5 � 106 spermatozoa/group) was induced with CaI (250 nM or 500 nM for 1 or 5 min). Capacitated sperm cells were incubated with 500 ng/mL DNA for 1 or 2 h. Nontreated spermatozoa were used as control group. Sperm cells (1 � 105) were used to inseminate 20 oocytes/90 mL microdroplets for 18 h. The presumptive zygotes were co-cultured in SOFaa medium with a granulosa cell monolayer under high humidified atmosphere, at 39�C and 5% CO2 in air. Blastocyst rates were analyzed by ANOVA. Independent variables were replicate, [CaI], tCa, tDNA, and the double and triple interactions among the last three variables; when appropriate, means were compared by orthogonal contrasts. There was [CaI] � tCa � tDNA interaction for blastocyst rate (P < 0.02). Treatments with 250 nM ([CaI]), 5 min (tCaI), and 1 h (tDNA) or 500 nM ([CaI]), 1 min (tCaI), and 1 h (tDNA) resulted in 36.1% and 37.4% blastocyst rates, respectively, similar to the control group (30.5%; P > 0.4). These results demonstrated that it is possible to capacitate spermatozoa with CaI to produce transgenic embryos, without alteration of blastocyst rate. This work was supported by FAPESP 03/08542-5 and 03/07456-8.

18 DEVELOPMENTAL COMPETENCE OF CLONED PORCINE EMBRYOS PRODUCED WITH DIFFERENT CLONING PROCEDURES

2014 ◽  
Vol 26 (1) ◽  
pp. 123
Author(s):  
Y. Liu ◽  
A. Lucas-Hahn ◽  
B. Petersen ◽  
R. Li ◽  
P. Hassel ◽  
...  
Keyword(s):  
In Vitro Culture ◽  
Nuclear Transfer ◽  
Cell Number ◽  
Culture Conditions ◽  
Developmental Competence ◽  
Cleavage Rate ◽  
Cell Numbers ◽  
Blastocyst Rate ◽  
Handmade Cloning

Two nuclear transfer (NT) techniques are routinely used to produce cloned animals, traditional cloning (TC) and handmade cloning (HMC). The TC embryos keep their zona and can be transferred at early stages, whereas HMC embryos are zona-free and must be cultured to the morula/blastocyst stage before transfer. Some studies have shown that in vitro culture reduces embryo development and quality, but it is not known whether embryos produced by TC or HMC differ because of the NT method or the in vitro culture. Therefore, we investigated the developmental competence and histone acetylation (H3K18ac) of porcine NT embryos produced by TC and HMC with (Day 5 and 6) or without (Day 0) in vitro culture. Nuclear transfer experiments were performed on same day (Day 0), using same batch of porcine oocytes and donor cells and same in vitro culture conditions. Cloning procedures were previously described (TC : Cloning Stem Cells 10 : 355; HMC : Zygote 20 : 61). Parthenogenetically activated embryos (PA) were used as control of activation and culture conditions. Embryos from all groups were collected for immunostaining of H3K18ac on Days 0, 5, and 6. The normalized H3K18ac level was calculated as previously described (Epigenetics 6 : 177). Cell numbers per blastocyst in each group were counted on Days 5 and 6. The cleavage rate (Day 2) and blastocyst rates (Days 5 and 6) between groups were analysed by Chi-squared test, whereas cell number per blastocysts and H3K18ac level between groups and days were analysed by ANOVA (SAS version 9.2; SAS Institute Inc., Cary, NC, USA). Cleavage rate of HMC embryos was lower than that of TC embryos, but blastocyst rate and cell number per blastocyst were higher in the HMC group compared with TC (Table 1). Differences of H3K18ac level between HMC, TC, and PA groups were only observed on Day 6 but not on Day 0 or Day 5. Within HMC and TC groups, there was no difference in H3K18ac level between Day 0 and Day 5, but the level was lower on Day 6 compared with Day 5 in the HMC group, whereas the TC group displayed the opposite pattern. In conclusion, NT embryos produced by HMC show higher blastocyst rate and cell number per blastocyst compared with TC embryos. Both in vitro culture and the NT method result in differences of the normalized H3K18ac levels. Further study is needed to investigate putative differences between NT embryos produced by HMC and TC compared to in vivo embryos also after transfer to recipients. Table 1.Cleavage and blastocyst rate, cell numbers, and normalized H3K18ac level for handmade cloning (HMC), traditional cloning (TC), and parthenogenetically activated (PA) embryos1

77 Development and quality of in vitro bovine hemi embryos produced by blastomere separation and embryo bisection

2019 ◽  
Vol 31 (1) ◽  
pp. 164
Author(s):  
A. E. Ynsaurralde Rivolta ◽  
M. Suvá ◽  
V. Alberio ◽  
C. Vazquez Echegaray ◽  
A. Guberman ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Monozygotic Twin ◽  
Cell Number ◽  
Control Group ◽  
Cell Stage ◽  
Exact Test ◽  
Development Rates

Bovine monozygotic production of twins became popular in the 1980s as a technique to multiply high value genetics. Moreover, it also became a powerful model for research. Different techniques have been used on bovine embryos obtained by superovulation. In this work, we compared the development rates and quality of monozygotic twin embryos produced by blastomere separation (BS) and embryo bisection (EB) of IVF embryos. To this aim, cumulus-oocytes complexes collected from slaughterhouse ovaries were in vitro matured in TCM 199 containing 10% fetal bovine serum, 10µg mL−1 FSH, 0.3mM sodium pyruvate, 100mM cysteamine, and 2% antibiotic-antimycotic for 24h, at 6.5% CO2 in humidified air and 38.5°C. The IVF was performed with 16×106 spermatozoa per mL for 5h. Afterward, presumptive zygotes were cultured in SOF medium for 7 days at 38.5°C and 5% O2. After 24h of culture, blastomeres of 2-cell stage embryos (N=114) were separated and each one was cultured individually in a microwell for 7 days. Embryo bisection (N=179) was performed manually on Day-7 blastocysts previously depleted of their zonae pellucidae, under stereoscopic microscope. Hemi embryos were cultured for 24h and then twins and single blastocyst rates were calculated. For quality assessment, diameter, total and inner cell mass (ICM) cell number of hemi embryos (BS: 6 couples; ES: 10 couples) and the control group (C: 11) were evaluated. The ICM cell number was measured by immunofluorescence staining using SOX2 antibody and the percentage of ICM and trophectoderm (TE) cells was calculated. The results were analysed using Fisher’s exact test and ANOVA with mean comparison using Tukey’s test (P=0.05). No statistical differences were found in blastocyst rates of twins and single hemi embryos produced by BS (28 and 25%) or EB (23 and 32%). Blastocyst diameter was similar between groups and control. Hemi embryos exhibited lower total and ICM cell number than control (BS: 43±18, EB: 57±14v. C: 93±35 and BS: 16±7, EB: 12±8v. C: 34±19). However, BS hemi embryos had higher ICM and lower TE percentage (40/60%) compared with the EB group (20/80%). The control group did not differ with hemi embryo treatments for ICM and TE (30/70%). Our preliminary results have indicated that although the development rates of hemi embryos produced in vitro were similar between both techniques, blastomere separation generates better quality embryos than blastocyst bisection.

Developments in in vitro technologies for swine embryo production

2004 ◽  
Vol 16 (2) ◽  
pp. 15 ◽  
Author(s):  
Matthew B. Wheeler ◽  
Sherrie G. Clark ◽  
David J. Beebe
Keyword(s):  
Culture Medium ◽  
Culture Media ◽  
Physical Culture ◽  
Efficient Production ◽  
Media Composition ◽  
In Vitro Production ◽  
Considerable Research ◽  
Blastocyst Rate ◽  
Vitro Production

Several modifications have been made to in vitro production (IVP) systems to allow more efficient production of viable porcine embryos. Although in vitro production of pig embryos has been studied for over 30 years, the overall blastocyst production rate remains low. The low blastocyst rate is due to several factors, including polyspermic oocyte penetration, low rate of male pronucleus formation and less than optimal in vitro culture systems. These conditions are all inherent problems in porcine IVP and many of the mechanisms involved remain unknown. Considerable research has examined culture medium and the techniques used during the various stages of in vitro production. However, changes to the physical culture system used during IVF have remained unchanged until recently. The present paper will summarise selected developments in fertilisation and embryo culture media composition and focus on the development of modified equipment to improve the conditions used during the IVP of porcine oocytes and embryos.

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