75 EFFECT OF PHENAZINE ETHOSULFATE ON PORCINE BLASTOCYST DEVELOPMENT, APOPTOSIS, AND CRYOTOLERANCE AFTER OPEN PULLED STRAW VITRIFICATION

2008 ◽  
Vol 20 (1) ◽  
pp. 118
Author(s):  
B. Gajda ◽  
Z. Smorag ◽  
M. Bryla

It is possible to improve the success of cryopreservation of in vitro-produced bovine embryos by modifying the embryos with the metabolic regulator phenazine ethosulfate (PES) (Seidel 2006 Theriogenology 65, 228–235). The PES treatment increased glucose matabolism, tended to increase the pentose phosphate pathway flux of glucose, and clearly reduced accumulation of lipids in cultured bovine embryos (De La Torre-Sanchez et al. 2006 Reprod. Fertil. Dev. 18, 597–607). It is known that porcine embryos have a considerably high content of lipids, and the success rates of their cryopreservation appear to be highly correlated with cytoplasmic lipid content. In our preliminary study, we observed that supplementation of NCSU-23 medium with PES has a positive effect on efficiency of pig blastocysts of good quality (Gajda et al.. 2007 Acta Biochim. Pol. 54(Suppl 1), 52 abst). In the present study, the effects of PES on pig blastocyst development, apoptosis, and survival after vitrification were investigated. In Exp. 1, porcine zygotes obtained from superovulated gilts were cultured in NCSU-23 medium supplemented with 0 (control), 0.025, 0.05, or 0.075 µm PES. The culture was performed at 39�C, with 5% CO2 in air, for 96–120 h. Embryo quality criteria were developmental competence (cleavage, morula stage, and blastocyst stage), cell number per blastocyst, and the degree of apoptosis as assessed by TUNEL staining. In Exp. 2, expanded blastocysts cultured with 0.025 µm PES were vitrified in a ethylene glycol and dimethyl sulfoxide mixture using open pulled straw (OPS) technology (Vajta et al. 1997 Acta Vet. Scand. 38, 349–352). After thawing, the blastocysts were cultured in vitro for re-expansion or transferred to synchronized recipients. Data were analyzed by chi-square test. There was a difference between the 0.025 µm PES-treated and the control group in percentage of cleaved embryos (99.0 and 91.4%, respectively; P < 0.05), between all experimental groups and control in percentage of morula stage (90.7, 87.8, 83.8, and 80.0%, respectively), and between 0.025 and 0.05 µm PES-treated and control in percentage of blastocyst rates (70.0, 75.5, and 65.7%, respectively). The number of cells and percentage of TUNEL-positive nuclei per blastocyst were lower in the PES-treated than in the control group. The survival rate of blastocysts after vitrification and thawing was enhanced in the presence of PES compared to that in the PES-free group (45.2 and 38.9%, respectively; P < 0.05). After transfer of 56 expanded blastocysts cultured with PES and vitrified into 3 recipients, two gilts were confirmed pregnant at 35 days of gestation. In conclusion, a higher blastocyst percentage with a low incidence of apoptosis was obtained in the presence of PES compared to control. These blastocysts also had an increased ability to survive cryopreservation.

2005 ◽  
Vol 17 (2) ◽  
pp. 269
Author(s):  
H. Alm ◽  
H. Torner ◽  
B. Loehrke ◽  
T. Viergutz ◽  
I. Ghoneim ◽  
...  

A large proportion of bovine oocytes fail to develop to blastocyst stage following maturation, fertilization, and culture in vitro. While suboptimal culture conditions undoubtedly contribute to this poor development, it is recognized that immature oocytes, especially from cows with reduced reproductive performance or which are slaughtered on the end of their use, are heterogeneous in quality and developmental competence (Gordon 2003). The aim of the present study was to increase the efficiency of blastocyst production from cows after IVM/IVF by oocyte selection before maturation. Immature oocytes are known to synthesize a variety of proteins (Wassarman PM 1988, Annu. Rev. Biochem. 57, 415–442), among them, glucose-6-phosphate dehydrogenase (G6PDH). This enzyme is active in the growing oocyte, but has decreased activity in oocytes that have finished their growth phase. Brilliant cresyl blue (BCB) has been used to measure G6PDH activity. The BCB test is based on the capability of the G6PDH to convert the BCB stain from blue to colorless (Erisson et al. 1993 Theriogenology 39, 214). The ovaries were obtained from a slaughterhouse and transported to the laboratory; cumulus-oocyte complexes (COCs) were recovered by slicing the surface of the ovary. Only oocytes with a compact cumulus investment were used. Oocytes were placed into three groups: (1) control – placed immediately into culture; (2) holding control – COCs kept in PBS containing 0.4% BSA for 90 min at 38.5°C before placement into culture; and (3) treatment – incubation with brilliant cresyl blue for 90 min at 38.5°C before culture. Treated oocytes were then divided into BCB− (colorless cytoplasm, increased G6PDH) and BCB+ (colored cytoplasm, low G6PDH) on their ability to metabolize the stain. Activity of G6PDH was determined via measurement of NADP reduction in control, BCB−, and BCB+ groups; activity was significantly increased in BCB− COCs in comparison to the control and BCB+ COCs. After IVM, oocytes were fertilized in vitro. Embryos were cultured to Day 8. The rate of maturation to metaphase II was significantly higher for control and BCB+ oocytes (77.1 and 72.5%, respectively) than for BCB− oocytes (58.1%). The BCB+ oocytes yielded a significantly higher proportion of blastocysts (34.1%) than either control group (18.3 and 19.2%); and both controls and BCB+ oocytes had significantly higher blastocyst development than did BCB− oocytes (3.9%). The number of nuclei in the blastocysts was comparable in BCB+ and both control groups (105.5 ± 5.8 and 117.5 ± 8.5, 101.8 ± 6.2, respectively). Blastocysts in the BCB− group had a significantly lower cell number (61.0 ± 2.6) than did controls. The results show that the staining of COCs from cows before IVM may be useful in increasing the efficiency of blastocyst production during standard IVF procedures. In addition, classification of G6PDH activity on the basis of BCB staining may be used to effectively select cow oocytes with further developmental competence. To our knowledge, this is the first study to evaluate the association between G6PDH activity in oocytes and further blastocyst development in cows.


2011 ◽  
Vol 23 (2) ◽  
pp. 311 ◽  
Author(s):  
Jamie E. Larson ◽  
Rebecca L. Krisher ◽  
G. Cliff Lamb

The objectives of the present experiment were to determine whether supplementation with progesterone (LO, 1 ng mL–1 or HI, 100 ng mL–1) during either the first (Culture-1, Day 1 to 3) or second (Culture-2, Day 4 to 7) phase of culture of in vitro-produced embryos alters embryo development, embryo metabolism or blastocyst cell number. The percentage of oocytes that cleaved, the percentage of cleaved embryos that developed to the morula stage or greater, the blastocyst stage or greater or the hatched blastocyst stage were similar among treatments. Quantities of glucose metabolised per blastocyst per hour were similar, but when metabolic data was normalised for numbers of cells in each blastocyst, the LO treatment during Culture-2 metabolised more glucose (P = 0.03) compared with all other treatments. Embryos receiving LO progesterone tended to have greater (P = 0.085) metabolism of glucose compared with embryos receiving HI progesterone. Quantities of pyruvate oxidised per blastocyst per hour, and per cell, were similar among treatments. The number of cells per blastocyst in the control group was increased (P = 0.039) compared with cells in progesterone-treated groups. In conclusion, supplementation with progesterone during the culture of in vitro-produced embryos does not appear to improve embryo characteristics.


2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4297
Author(s):  
Luciana Simões Rafagnin Marinho ◽  
Lain Uriel Ohlweiler ◽  
Marcos Henrique Barreta ◽  
Paulo Bayard Dias Gonçalves ◽  
Joana Claudia Mezzalira ◽  
...  

<p>Conjugated linoleic acid (CLA) might be able to improve the cryotolerance of <em>in vitro-</em>produced (IVP) embryos. The effect of two CLA isomers on the cryotolerance of bovine IVP embryos, as well as that of the stage of embryonic development and the method used for cryopreservation was evaluated by three experiments. In Experiment 1, oocytes (n = 3,917) were fertilized <em>in vitro </em>and cultured with 0, 50, 100, or 200 ?M <em>trans-</em>10<em>, cis-</em>12 (t10, c12 CLA). In Experiment 2, fertilized oocytes (n = 2,131) were cultured with 100 ?M t10, c12 or <em>cis-</em>9<em>, trans-</em>11 (c9<em>, </em>t11 CLA), or a combination of both isomers. The embryos were vitrified at the blastocyst (BL) or the expanded blastocyst (EB) stage. In Experiment 3, oocytes (n = 1,720) were fertilized and cultured with or without 100 ?M t10, c12 CLA, and the blastocysts were vitrified or frozen. Blastocyst development rate as well as the rates of re-expansion and hatching after thawing was recorded. Moreover, the mean cell number and mRNA expression of acetyl-CoA carboxylase (ACC1) and stearoyl-CoA desaturase (SCD1) as well as fatty acid synthase (FASN) multienzyme complex were determined. In Experiment 1, the highest concentration of t10, c12 CLA that did not reduce blastocyst development rate was 100 ?M. In Experiment 2, the rates of re-expansion and hatching among the EBs obtained through IVP after supplementation with t10, c12 CLA (73.1% and 57.7%), with c9, t11 CLA (80.0% and 68.6%), with the combination (78.3% and 52.2%), and with the control group (85.4% and 58.3%) were similar. At the BL stage, the rates of re-expansion and hatching were lower than those at the EB stage, and CLA combination allowed a hatching rate (8.0%) lower than that observed in the control group (40.0%). In Experiment 3, the hatching rates for vitrified EBs (vitrified control; 67.4%) and vitrified CLA EBs (65.8%) were higher than those obtained for frozen EBs, exposed (13.3%) or not exposed (28.6%) to CLA. In addition, in Experiment 3, the hatching rate was higher at the EB stage in vitrified groups, while the rates of BL and EB were similar in frozen groups, thus proving that vitrification was more efficient than freezing for IVP bovine embryos. In Experiment 3, CLA isomer t10, C12 did not influence the embryonic cell number or mRNA expression of ACC1 and SCD1 enzymes, but decreased the mRNA expression of FASN. In conclusion, 100 ?M CLA did not affect subsequent embryonic development. However, neither CLA isomer improved the cryotolerance of IVP bovine embryos.</p>


Reproduction ◽  
2013 ◽  
Vol 146 (4) ◽  
pp. 407-417 ◽  
Author(s):  
A Z Balboula ◽  
K Yamanaka ◽  
M Sakatani ◽  
M Kawahara ◽  
A O Hegab ◽  
...  

Cathepsin B was found to be correlated inversely with the quality of bovine oocytes and embryos. The aims of this study were to evaluate i) the relationship between heat shock during in vitro maturation (IVM) of bovine cumulus–oocyte complexes (COCs) and cathepsin B activity in relation to apoptosis and ii) the effect of supplementation of cathepsin B inhibitor (E-64) during IVM of heat-shocked COCs on embryonic development. After IVM at 38.5 °C for 22 h (control group) or at 38.5 °C for 5 h followed by 41 °C for 17 h (heat shock group) either with or without 1 μM E-64, activities and protein expression of cathepsin B and caspase 3 were evaluated as well as TUNEL staining. After IVF, developmental rate, total cell number, and the percentage of apoptotic cells in blastocysts were evaluated on day 8 (day 0, IVF day). Heat-shocked IVM COCs showed significantly high activities and expressions of both cathepsin B, and caspase 3 accompanied by a significant increase in number of TUNEL-positive cells. Addition of E-64 significantly decreased the activities of cathepsin B and caspase 3, and TUNEL-positive cells in heat-shocked IVM COCs. Moreover, addition of 1 μM E-64 during IVM under heat shock conditions significantly improved both developmental competence and quality of the produced embryos. These results indicate that heat shock induction of cathepsin B is associated with apoptosis of COCs, and inhibition of cathepsin B activity can improve the developmental competence of heat-shocked COCs during IVM.


2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4297
Author(s):  
Luciana Simões Rafagnin Marinho ◽  
Lain Uriel Ohlweiler ◽  
Marcos Henrique Barreta ◽  
Paulo Bayard Dias Gonçalves ◽  
Joana Claudia Mezzalira ◽  
...  

Conjugated linoleic acid (CLA) might be able to improve the cryotolerance of in vitro-produced (IVP) embryos. The effect of two CLA isomers on the cryotolerance of bovine IVP embryos, as well as that of the stage of embryonic development and the method used for cryopreservation was evaluated by three experiments. In Experiment 1, oocytes (n = 3,917) were fertilized in vitro and cultured with 0, 50, 100, or 200 ?M trans-10, cis-12 (t10, c12 CLA). In Experiment 2, fertilized oocytes (n = 2,131) were cultured with 100 ?M t10, c12 or cis-9, trans-11 (c9, t11 CLA), or a combination of both isomers. The embryos were vitrified at the blastocyst (BL) or the expanded blastocyst (EB) stage. In Experiment 3, oocytes (n = 1,720) were fertilized and cultured with or without 100 ?M t10, c12 CLA, and the blastocysts were vitrified or frozen. Blastocyst development rate as well as the rates of re-expansion and hatching after thawing was recorded. Moreover, the mean cell number and mRNA expression of acetyl-CoA carboxylase (ACC1) and stearoyl-CoA desaturase (SCD1) as well as fatty acid synthase (FASN) multienzyme complex were determined. In Experiment 1, the highest concentration of t10, c12 CLA that did not reduce blastocyst development rate was 100 ?M. In Experiment 2, the rates of re-expansion and hatching among the EBs obtained through IVP after supplementation with t10, c12 CLA (73.1% and 57.7%), with c9, t11 CLA (80.0% and 68.6%), with the combination (78.3% and 52.2%), and with the control group (85.4% and 58.3%) were similar. At the BL stage, the rates of re-expansion and hatching were lower than those at the EB stage, and CLA combination allowed a hatching rate (8.0%) lower than that observed in the control group (40.0%). In Experiment 3, the hatching rates for vitrified EBs (vitrified control; 67.4%) and vitrified CLA EBs (65.8%) were higher than those obtained for frozen EBs, exposed (13.3%) or not exposed (28.6%) to CLA. In addition, in Experiment 3, the hatching rate was higher at the EB stage in vitrified groups, while the rates of BL and EB were similar in frozen groups, thus proving that vitrification was more efficient than freezing for IVP bovine embryos. In Experiment 3, CLA isomer t10, C12 did not influence the embryonic cell number or mRNA expression of ACC1 and SCD1 enzymes, but decreased the mRNA expression of FASN. In conclusion, 100 ?M CLA did not affect subsequent embryonic development. However, neither CLA isomer improved the cryotolerance of IVP bovine embryos.


2005 ◽  
Vol 17 (2) ◽  
pp. 219 ◽  
Author(s):  
C.E. Ferguson ◽  
T.R. Davidson ◽  
M.R.B. Mello ◽  
A.S. Lima ◽  
D.J. Kesler ◽  
...  

There has been much debate over a direct role for progesterone (P4) in early bovine embryo development. While previous attempts to supplement bovine embryos in vitro with P4 produced results that vary and are often contradictory, this may be a response of administering P4 at inappropriate times. Therefore, the objective of these experiments was to determine if P4 could exert a direct effect on developing IVF-derived bovine embryos when administered at an appropriate time of embryo development. In Exp. I, IVF-derived bovine 8-cell embryos were randomly allotted to treatments: (1) control, CR1aa medium (n = 168); (2) vehicle, CR1aa + ETOH (0.01%) (n = 170); and (3) P4, CR1aa + ETOH + P4 (20 ng/mL in 50-μL droplet) (n = 173). In Exp. II, IVF-derived bovine 8-cell embryos were randomly allotted to treatments: (1) control, CR1aa medium (n = 160); (2) vehicle, CR1aa + DMSO (0.01%) (n = 180); and (3) P4, CR1aa + DMSO (0.01%) + P4 (20 ng/mL in 50-μL droplet) (n = 170). All embryos were evaluated on Days 6 to 9 post-insemination and rates calculated from 8-cell embryos. In Exp. I, ETOH tended to have a detrimental effect with significantly fewer (P < 0.05) embryos (53%) developing to the blastocyst stage on Day 7 compared with the control (62%) and P4 (71%) groups. At Day 7, significantly more embryos cultured in P4 (71%) developed to the blastocyst stage compared with the control group (62%). P4 treatment significantly increased the number of Grade 1 blastocysts (25%) on Day 7 compared with vehicle (15%) and control (17%) groups. At the end of culture, there were also significantly more Day 9 hatched blastocysts in the P4 group (33%) compared with vehicle (22%) and control (21%) groups. Supplementing P4 in the culture medium increased the rate of development, resulting in significantly more blastocysts (8%) on Day 6 and hatched blastocysts (21%) on Day 8 compared with vehicle (3% and 12%) and control (0% and 8%) groups, respectively. In Exp. II, there were no significant differences between treatment groups for Day 7 blastocysts (control 54%, DMSO 61%, P4 57%) and Day 9 hatched blastocysts (control 46%, DMSO 51%, P4 46%). However, there were significantly more Grade 1 blastocysts in the P4 group (22% and 36%) on Days 6 and 8 compared with vehicle (11% and 23%) and control (13% and 23%) groups, respectively. The lack of improvement in Day 7 blastocysts and Day 9 hatched blastocysts rates leads to further uncertainty in understanding the P4 vehicle interactions. In conclusion, the results of these two experiments indicate that P4 can exert a direct effect on the developing IVF-derived bovine embryo; however, due to P4 vehicle interactions; other inert vehicles need to be explored to further evaluate the direct effects of P4 on the developing bovine embryo.


2007 ◽  
Vol 19 (1) ◽  
pp. 203
Author(s):  
S. R. Cho ◽  
S. H. Choi ◽  
H. J. Kim ◽  
C. Y. Choe ◽  
H. J. Jin ◽  
...  

The present study was carried out to investigate the effect of different ovary transport temperatures on in vitro development and post-thaw survivability of bovine embryos. Bovine ovaries were collected at a local slaughterhouse and transported at 4 different temperature categories to the laboratory: 7–10�C (T1), 11–17�C (T2), 18–25�C (T3), and above 26�C (control group). The cumulus–oocyte complexes (COCs) were aspirated from 2–8 mm antral follicles using a syringe with an 18 gauge needle. Selected COCs were washed in HEPES-buffered tissue culture medium (TCM-199) supplemented with 5% FBS. Sets of 50 COCs were matured for 22 h in 4-well dishes of TCM-199 supplemented with 5% FBS, 10 �g mL-1 LH, and 10 �g mL-1 FSH, that had been previously covered with mineral oil and equilibrated in an atmosphere of 5% CO2 in air at 39�C. Mature COCs were fertilized with frozen–thawed semen treated with BO medium. To evaluate nuclear maturation to the metaphase II stage, the matured COCs were fixed in 1 : 3 acetic acid–ethanol for 30 s and stained with 3% basic Fuchsin. For embryo freezing, Day 7 and 8 blastocysts were equilibrated for 15 min in 1.8 M ethylene glycol as a cryoprotectant. Embryos were loaded into 0.25-mL straws at room temperature, plunged directly into a cooling chamber, kept at -7�C for 10 min, including time for seeding, and further cooled to -35�C at -0.3�C min-1; after 2 min at this temperature, they were plunged into liquid nitrogen. Thawing was performed by keeping straws at room temperature for 10 s, followed by immersion in a water bath at 37�C. The appearance of the embryos was evaluated immediately after warming and again at 24-h intervals for at least 3 days. The development rate was assessed by the re-expansion of the blastocoel and the hatching of blastocysts. Results were compared by ANOVA. The rates of maturation (to metaphase II), cleavage, and development to blastocysts were compared among treatment groups. Furthermore, frozen–thawed blastocysts were in vitro cultured to compare the survivability among groups. The maturation rates in the T1, T2, and T3 groups (24/40, 60.0%; 25/41, 61.0%; and 30/44, 68.2%, respectively) were significantly lower than that in the control group (36/44, 81.8%; P &lt; 0.05). The cleavage rates in the T1 and T2 groups (61/116, 52.6% and 66/121, 54.5%) were significantly lower than that in the control group (112/134, 83.6%; P &lt; 0.05). However, there was no difference in the development rate to blastocysts among all groups (27.9–33.0%; P &gt; 0.05). The survivability of frozen–thawed embryos was significantly lower in the T1 group (6/13, 46.2%) than in the T2 (11/16, 68.8), T3 (13/18, 72.2%), and control groups (19/26, 73.1%; P &lt; 0.05). In conclusion, the results suggest that ovary transport at 26�C may be optimal for better in vitro development and survival of frozen–thawed embryos produced in vitro. Furthermore, exposure of ovaries to temperatures below 10�C during transport may significantly decrease both in vitro development and survivability of frozen-thawed blastocysts.


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 ◽  
...  

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.


2013 ◽  
Vol 25 (1) ◽  
pp. 260 ◽  
Author(s):  
I. Grad-Mandryk ◽  
J. Kosenyuk ◽  
B. Gajda

In vitro production of porcine embryos is still relatively inefficient. The main reasons for this limited performance are polyspermy after IVF and the poor developmental ability of obtained zygotes. Intracytoplasmic sperm injection (ICSI) is one possible solution to eliminate polyspermy. The aim of this study was to compare the developmental competence of pig zygotes, total cell number, and DNA fragmentation of pig blastocysts derived from IVF or ICSI. Cumulus–oocyte complexes were obtained by aspiration from antral follicles of ovaries collected from slaughtered gilts. The oocytes were then cultured in modified TC-199 medium to metaphase II for 42 h. Semen for IVF was incubated in modified capacitation medium (M199) for 1 h. The sperm fraction (1 × 106 cells mL–1) was introduced into droplets containing oocytes, and then gametes were co-incubated for 4 h in modified TC-199 medium. Intracytoplasmic sperm injection was performed using a mechanical micromanipulator (Research Instruments Limited, Cornwall, UK). Micromanipulation was carried out in modified NCSU-37 medium. The tails of spermatozoa were broken, and then single spermatozoa were aspirated into the injection pipette. The oocyte was fixed by a holding pipette, and the sperm head was then introduced into the oocyte cytoplasm. Presumptive zygotes were cultured in vitro for 144 h in NCSU-23 medium. The embryo quality criteria were developmental competence (morula and blastocyst rates), total cell number per blastocyst, and degree of apoptosis assessed by TUNEL staining. Data were analysed by chi-squared test. The experiment was performed on 136 zygotes (6 replicates) obtained after IVF and 83 zygotes (4 replicates) obtained after ICSI. Percentages of embryos developed to the morula and blastocyst stages were 42.3 ± 6.1 and 28.8 ± 4.7 after IVF, respectively, and 51.7 ± 15.4 and 34.5 ± 18.9 after ICSI, respectively (no differences were observed). Significant differences were noticed in total number of cells per blastocyst between embryos after IVF and ICSI (33.7 ± 5.39 v. 22.8 ± 3.22; P < 0.01). However, there was no difference in the degree of apoptosis between IVF and ICSI embryos (5.14 ± 3.49 and 6.14 ± 4.88, respectively). Our preliminary studies demonstrated a higher proportion of cell numbers in IVF-derived embryos compared with those produced by ICSI, but the developmental competence and degree of apoptosis, as evaluated by the TUNEL method, in both groups were comparable. This study was funded by project N N311 516140 by the NCN, Poland.


2009 ◽  
Vol 21 (1) ◽  
pp. 157 ◽  
Author(s):  
B. Gajda ◽  
I. Grad ◽  
Z. Smorag

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.


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