114 DEVELOPMENT OF AN OPTIMIZED WELL IN WELL CULTURE SYSTEM: EFFECT OF MINIWELL CALIBER AND CULTURE DROP VOLUME ON DEVELOPMENTAL COMPETENCE OF BOVINE EMBRYOS

2009 ◽  
Vol 21 (1) ◽  
pp. 157
Author(s):  
M. Hoelker ◽  
N. Gahnem ◽  
C. Phatsara ◽  
K. Schellander ◽  
D. Tesfaye
Keyword(s):  
Treatment Group ◽  
Culture System ◽  
Culture Medium ◽  
Culture Media ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Bovine Embryos ◽  
System Effect ◽  
Developmental Problems ◽  
Developmental Rates

To overcome developmental problems due to the scientific need to track single embryos or due to embryo culture in small groups, the Well in Well culture system has been developed previously. Here we aimed to examine the effects of different MiniWell caliber and different embryo densities on developmental rates. Cumulus oocyte complexes (COC) aspirated from small follicles (2–8 mm) were cultured in modified TCM (TCM199, Sigma, Taufkirchen, Germany) supplemented with 12% heat inactivated oestrus cow serum and 10 μg mL–1 FSH (FSH-p, Sheering, Kenilworth, NJ, USA) for 24 h at 39°C in a humidified atmosphere with 5% CO2 in air. Fertilization was performed in Fert-TALP medium. After 20 h coincubation with sperm cells, presumptive zygotes were allocated into MiniWells of different diameter (0.3, 0.4, 0.5, and 0.7 mm) and depth (0.3, 0.5, and 0.7 mm) to investigate the effect of MiniWell diameter and depth on further development of the embryos. To investigate the effect of embryo density we compared the development of zygotes placed in MiniWells with different total volumes of culture medium per well. For all experiments bovine embryos cultured in groups of 16 and groups of 50 served as controls. Developmental rates of in vitro-produced embryos were analysed by chi-square test. Differences of P < 0.05 were considered to be significant. When embryos were cultured in a 4 × 3 factorial design (n = 240 per treatment group in 16 replicates), MiniWell diameter (0.3 mm v. 0.4 mm v. 0.5 mm v. 0.7 mm) significantly affected developmental rates to the blastocyst stage (21.5% v. 26.9% v. 32.5% v. 31.3%, respectively) and MiniWell depth (0.3 mm v. 0.5 mm v. 0.7 mm) influenced development (24.4% v. 27.4% v. 29.3%, respectively). When embryos (n = 160 per treatment group in 10 replicates) were cultured in different total volumes of culture media per Well (0 μL, v. 150 μL v. 500 μL) development of embryos to the blastocyst stage (3.1% v. 13.1% v. 33.1%, respectively) differed significantly. When a total of 240 embryos cultured in 15 replicates in group of 16 were compared with a total of 750 embryos cultured in 15 replicates in group of 50, embryos cultured in group of 16 reached the blastocyst stage at a significantly lower level than zygotes cultured in the group of 50 (22.2% v. 30.3%), whereas zygotes cultured in MiniWells were able to compensate against low embryo densities reaching a blastocyst rate as high as embryos cultured in group of 50 (31.3 v. 30.3%). The best developmental rate of bovine zygotes to the blastocyst stage was observed in MiniWells with a diameter of 0.7 mm and 0.7 mm depth in 500 μL culture medium per well. In conclusion, we successfully optimized the Well in Well culture system by exploring the most suitable MiniWell properties supporting improved developmental rates to the blastoyst stage by compensating against negative effects of low embryo densities allowing to track each individual embryo over the complete culture period.

scholarly journals MicroRNAs from Extracellular Vesicles Secreted by Bovine Embryos as Early Biomarkers of Developmental Competence

2020 ◽  
Vol 21 (23) ◽  
pp. 8888
Author(s):  
Bárbara Melo-Baez ◽  
Yat S. Wong ◽  
Constanza J. Aguilera ◽  
Joel Cabezas ◽  
Ana C. F. Mançanares ◽  
...  
Keyword(s):  
Extracellular Vesicles ◽  
Fatty Acid Biosynthesis ◽  
Culture Media ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Target Cells ◽  
Bovine Embryos ◽  
Developmental Potential ◽  
Maternal Communication

During early development, embryos secrete extracellular vesicles (EVs) that participate in embryo–maternal communication. Among other molecules, EVs carry microRNAs (miRNAs) that interfere with gene expression in target cells; miRNAs participate in embryo–maternal communication. Embryo selection based on secreted miRNAs may have an impact on bovine breeding programs. This research aimed to evaluate the size, concentration, and miRNA content of EVs secreted by bovine embryos with different developmental potential, during the compaction period (days 3.5–5). Individual culture media from in vitro–produced embryos were collected at day 5, while embryos were further cultured and classified at day 7, as G1 (conditioned-culture media by embryos arrested in the 8–16-cells stage) and G2 (conditioned-culture media by embryos that reached blastocyst stages at day 7). Collected nanoparticles from embryo conditioned culture media were cataloged as EVs by their morphology and the presence of classical molecular markers. Size and concentration of EVs from G1 were higher than EVs secreted by G2. We identified 95 miRNAs; bta-miR-103, bta-miR-502a, bta-miR-100, and bta-miR-1 were upregulated in G1, whereas bta-miR-92a, bta-miR-140, bta-miR-2285a, and bta-miR-222 were downregulated. The most significant upregulated pathways were fatty acid biosynthesis and metabolism, lysine degradation, gap junction, and signaling pathways regulating pluripotency of stem cells. The characteristics of EVs secreted by bovine embryos during the compaction period vary according to embryo competence. Embryos that reach the blastocyst stage secrete fewer and smaller vesicles. Furthermore, the loading of specific miRNAs into the EVs depends on embryo developmental competence.

In vitro culture and non-invasive metabolic profiling of single bovine embryos

2019 ◽  
Vol 31 (2) ◽  
pp. 306
Author(s):  
Monika Nõmm ◽  
Rando Porosk ◽  
Pille Pärn ◽  
Kalle Kilk ◽  
Ursel Soomets ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Metabolic Profiling ◽  
Culture Medium ◽  
Culture Media ◽  
Blastocyst Stage ◽  
Growth Media ◽  
Low Molecular Weight ◽  
Bovine Embryos ◽  
Non Invasive

Selecting high-quality embryos for transfer has been a difficult task when producing bovine embryos invitro. The most used non-invasive method is based on visual observation. Molecular characterisation of embryo growth media has been proposed as a complementary method. In this study we demonstrate a culture medium sampling method for identifying potential embryonic viability markers to predict normal or abnormal embryonic development. During single embryo culture, 20µL culture media was removed at Days 2, 5 and 8 after fertilisation from the same droplet (60µL). In all, 58 samples were analysed using liquid chromatography–mass spectrometry. We demonstrate that it is possible to remove samples from the same culture medium droplets and not significantly affect blastocyst rate (25.2%). Changes in any single low molecular weight compound were not predictive enough. Combining multiple low molecular weight signals made it possible to predict Day 2 and 5 embryo development to the blastocyst stage with an accuracy of 64%. Elevated concentrations of lysophosphatidylethanolamines (m/z=453, 566, 588) in the culture media of Day 8 well-developing embryos were observed. Choline (104m/z) and citrate (215m/z) concentrations were increased in embryos in which development was retarded. Metabolic profiling provides possibilities to identify well-developing embryos before transfer, thus improving pregnancy rates and the number of calves born.

98 EXPERIMENTAL TRANSFER OF BOVINE IVF-DERIVED 32-CELL STAGE EMBRYOS INTO THE UTERUS: ENVIRONMENTAL EFFECTS ON DEVELOPMENTAL CHARACTERISTICS

2016 ◽  
Vol 28 (2) ◽  
pp. 179
Author(s):  
M. Hoelker ◽  
D. Salilew-Wondim ◽  
F. Rings ◽  
D. Tesfaye ◽  
K. Schellander
Keyword(s):  
Culture Media ◽  
Uterine Cavity ◽  
Blastocyst Stage ◽  
Considerable Proportion ◽  
Bovine Embryo ◽  
Bovine Embryos ◽  
Cell Stage ◽  
Developmental Rates ◽  
Uterine Environment

Usually, in vitro-produced bovine embryos are cultured in vitro in static culture systems for 7 to 9 days in media composed according the oviducal fluid although it is well accepted that around Day 4.5–5 the bovine embryo enters the uterine cavity, providing environmental conditions different from the oviduct. Therefore, one has to raise the question whether changing culture media properties after Day 5 of culture could have beneficial effects on early development of bovine embryos. To answer that question, we transferred bovine IVF derived 32-cell stage embryos into the uterine cavity of synchronized recipients. All embryos had been matured and fertilized under routine standard conditions and were cultured in synthetic oviducal fluid supplemented with essential and nonessential amino acids (SOFaa) supplemented with either 0.3% fatty acid free bovine serum albumin (BSAfaf/Uterus) or 10% serum (serum/uterus) at 38.5°C, 5% O2, and 5% CO2 in humidified air prior transfer into the uterine environment, allowing further development to the blastocyst stage within the physiological environment prior recollection at Day 7 by routine uterine flushing followed by comparison with statically in vitro-developed embryos cultured in media supplemented with serum (serum/serum group) or BSAfaf (BSAfaf/BSAfaf group). All in all, a total of 1031 in vitro-derived 32-cell stage embryos were transferred to 21 synchronized Simmental recipient heifers. Of these, a total of 680 embryos (66%) could be recollected at Day 7. Embryos of the serum/serum group reached a higher blastocyst rate compared with embryos of the BSAfaf/BSAfaf group (68% v. 41%; P < 0.05, ANOVA, Tukey test), whereas the developmental rate to the blastocyst stage did not differ after 9 days of in vitro culture, indicating higher developmental kinetics of bovine 32-cell stage embryos when culture media is supplemented with serum. Moreover, embryos of the serum/uterus group reached significantly lower developmental rates to the blastocyst stage until Day 7 compared with embryos of the serum/serum group (12.9% v. 68.4%). Likewise, embryos in the BSAfaf/uterus group reached significantly lower developmental rates to the blastocyst stage until Day 7 compared with embryos in the BSAfaf/BSAfaf group (16.0% v. 40.1%). When allowed to develop for additional 48h in vitro, developmental rates to the blastocyst stage at Day 9 were still higher in BSAfaf/BSAfaf treatment compared with the BSAfaf/uterus treatment (91.4% v. 74.4%) and the serum/serum treatment compared with the serum/uterus treatment (92.5% v. 56.0%). Taken together, the results of our study demonstrate that uterine transfer of bovine 32-cell stage embryos results in reduction of developmental kinetics as well as lower developmental rates compared with embryos statically cultured in vitro. That might indicate, that a considerable proportion of bovine 32-cell stage embryos might not be able to adapt to the uterine environment.

Biochemical markers for pregnancy in the spent culture medium of in vitro produced bovine embryos

2021 ◽  
Author(s):  
Gabriela de Oliveira Fernandes ◽  
Marcella Pecora Milazzotto ◽  
Andrei Antonioni Guedes Fidelis ◽  
Taynan Stonoga Kawamoto ◽  
Ligiane de Oliveira Leme ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Biochemical Markers ◽  
Culture Medium ◽  
Culture Media ◽  
Ionization Mass ◽  
Metabolic Profiles ◽  
Bovine Embryos ◽  
The Media

Abstract The present study aimed to identify biomarkers to assess the quality of in vitro produced (IVP) bovine embryos in the culture media. IVP embryos on Day (D) 5 of development were transferred to individual drops, where they were maintained for the last 48 h of culture. Thereafter, the medium was collected and the embryos were transferred to the recipients. After pregnancy diagnosis, the media were grouped into the pregnant and nonpregnant groups. The metabolic profiles of the media were analyzed via electrospray ionization mass spectrometry, and the concentrations of pyruvate, lactate, and glutamate were assessed using fluorimetry. The spectrometric profile revealed that the media from embryos from the pregnant group presented a higher signal intensity compared to that of the nonpregnant group; the ions 156.13 Da [M + H]+, 444.33 Da [M + H]+, and 305.97 Da [M + H]+ were identified as biomarkers. Spent culture medium from expanded blastocysts (Bx) that established pregnancy had a greater concentration of pyruvate (p = 0.0174) and lesser concentration of lactate (p = 0.042) than spent culture medium from Bx that did not establish pregnancy. Moreover, pyruvate in the culture media of Bx can predict pregnancy with 90.9% sensitivity and 75% specificity. In conclusion, we identified markers in the culture media that helped in assessing the most viable IVP embryos with a greater potential to establish pregnancy.

178 IMPROVED DEVELOPMENTAL COMPETENCE OF BOVINE EMBRYOS BY PGI2 ANALOG TREATMENT

2006 ◽  
Vol 18 (2) ◽  
pp. 197 ◽  
Author(s):  
B. S. Song ◽  
J. S. Kim ◽  
D. B. Koo ◽  
J. S. Park ◽  
K. K. Lee ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Culture Media ◽  
Cell Mass ◽  
Developmental Rate ◽  
Treated Group ◽  
Developmental Competence ◽  
Bovine Embryos ◽  
Frozen Semen ◽  
Oviductal Fluid

The microenvironment of the follopian tube, in which the oviductal fluid contains a variety of cytokines and growth factors, affects pre-implantation development of fertilized embryos in mammals. Prostaglandin I2 (PGI2, prostacyclin) exists in oviductal fluid and is synthesized from arachidonic acid by prostacyclin synthetase. PGI2 also enhances the implantation rate of mouse embryos. In this study, the effect of PGI2 analog on the development of bovine embryos was examined. Bovine cumulus oocytes complexes (COCs) were matured in TCM-199 medium supplemented with 10 IU/mL pregnant mare serum gonadotropin (PMSG), 10 IU/mL hCG, and 10 ng/mL epidermal growth factor (EGF) at 39�C, 5% CO2 in air for 20-22 h. Following in vitro maturation, COCs were fertilized in Fert-TALP medium containing 0.6% BSA using frozen semen. Also, oocytes matured in vitro were enucleated, individually reconstructed with bESF cells, fused, and then activated by treatment with 5 �M ionomycin for 5 min and 2 mM 6-DMAP for 4 h. In vitro-fertilized (IVF) and nuclear-transferred (NT) eggs were cultured in 50 ��L drops of CR1-aa medium supplemented with 0.3% BSA in the absence or presence of 1 �M PGI2 analog at 39�C, 5% CO2 in air, respectively. At 3 days of culture, cleaved embryos were further cultured in the same culture media supplemented with 10% FBS for 4 days. Allocations of blastocysts to inner cell mass (ICM) and trophoblast (TE) cells were investigated to assess embryo quality. All experiments were repeated more than three times. All data were analyzed by using the Duncan test of ANOVA by the Statistical Analysis System (SAS Institute, Inc., Cary, NC, USA) and numbers of nuclei in blastocysts were expressed as mean � SE. No difference was detected in the cleaved rate of the eggs between the treated- and nontreated groups. IVF zygotes treated with PGI2 analog represented a higher developmental rate (33%, 122/418) to the blastocyst stage than nontreated controls (24%, 107/456) (P < 0.05). Among IVF-derived blastocysts, interestingly, the proportion (46%, 84/181) of expanded blastocysts was significantly higher in the PGI2 analog-treated group compared with that in the nontreated group (28%, 46/164). The number of nuclei in (165 � 6.1, n = 15) in blastocysts in the PGI2 analog-treated group was higher than that (146.12 � 5.7, n = 18) in the nontreated group (P < 0.05). No difference was detected in the ratio of ICM to total cells between PGI2 analog-treated (42.0 � 3.0%) and nontreated groups (41.9 � 2.9%). Like the IVF embryos, NT embryos in the PGI2 analog-treated group showed a higher in vitro developmental rate (33.6%, 43/128) than the nontreated embryos (24.2%, 32/132) (P < 0.05). Our results indicate that PGI2 analog improves the kinetics of embryo development in cattle.

284 COMPARATIVE FERTILITY OF FRESHLY-COLLECTED VERSUS FROZEN - THAWED SPERMATOZOA FOR IN VITRO FERTILIZATION IN THE FISHING CAT (PRIONAILURUS VIVERRINUS)

2006 ◽  
Vol 18 (2) ◽  
pp. 249
Author(s):  
G. Magarey ◽  
J. Herrick ◽  
K. Thiangtum ◽  
W. Tunwattana ◽  
W. Swanson
Keyword(s):  
Sperm Motility ◽  
Culture Medium ◽  
Culture Media ◽  
Egg Yolk ◽  
Ovarian Follicles ◽  
Blastocyst Stage ◽  
Motile Sperm ◽  
Vitro Fertilization ◽  
International Transport

Wild populations of fishing cats (Prionailurus viverrinus) in Southeast Asia are in decline, primarily due to habitat loss. Because the fishing cat population in North American zoos is small (n = 69) and inbred (F = 0.17) with relatively low genetic variation (86%), infusion of new founder genes from Asia is a conservation priority. Importation of cryopreserved semen for use with IVF and ET may offer one alternative to the international transport of living animals. In this study, our objectives were to (1) compare motility longevity of fresh vs. frozen-thawed fishing cat spermatozoa in two culture media, (2) evaluate ovarian responses to exogenous gonadotropins, and (3) assess development of IVF embryos produced with fresh vs. frozen-thawed spermatozoa. Raw semen was collected via electroejaculation from male fishing cats (n = 4), divided into groups, and washed. Two sperm pellets were resuspended in either Ham's F10 medium (HF10; with 5% FBS) or our feline optimized culture medium (FOCM; with 0.4% BSA); another pellet was diluted in TEST egg yolk, cooled to 5�C over 3 h, glycerated (4%), and cryopreserved in straws over LN2 vapor. Frozen sperm samples were thawed, washed, and diluted in either HF10 or FOCM. Fresh and frozen-thawed sperm motility (percent motile, rate of forward progress) in each medium (10 � 106 motile sperm/mL) was assessed (at 0, 1, 3, and 6 h) in microdrops under oil during culture (38�C; 6% CO2 in air). Female fishing cats (n = 10) were treated with exogenous gonadotropins (150 IU eCG, 100 IU hCG, 85-h interval) and ovarian follicles were aspirated laparoscopically. Recovered oocytes were inseminated with fresh (2 � 105 motile sperm/mL) or frozen-thawed (5 � 105 motile sperm/mL) spermatozoa in FOCM microdrops; resulting embryos were either cryopreserved or cultured in FOCM (with 5% FBS added at 72 h post-insemination) for 7 days. Sperm motility over time did not differ (P > 0.05) between media for either fresh or frozen-thawed samples; however, across media, frozen-thawed sperm motility was lower (P < 0.05) and declined faster (P < 0.05) compared to fresh spermatozoa. Females produced an average (�SEM) of 9.8 � 2.9 mature ovarian follicles, allowing recovery of 7.3 � 2.6 high-quality oocytes per female. Oocyte cleavage percentage at 42 h p.i. was lower (P < 0.05) with frozen-thawed spermatozoa (38%, 11/29) compared to freshly collected spermatozoa (68%, 17/25). Overall, 35% (6/17) of cultured embryos developed to blastocysts with no difference (P > 0.05) between embryos produced with frozen-thawed (4/11) vs. fresh (2/6) spermatozoa. Although fishing cat sperm motility and fertility appear compromised after cryopreservation, our results demonstrate the ability of frozen-thawed spermatozoa to produce IVF embryos that are capable of developing to blastocyst stage in vitro. This work was supported by (NIH RR015388).

136 ADDITION OF LOW DENSITY LIPOPROTEIN TO CHEMICALLY DEFINED PORCINE EMBRYO CULTURE MEDIUM CAN PARTIALLY REPLACE BOVINE SERUM ALBUMIN

2008 ◽  
Vol 20 (1) ◽  
pp. 148
Author(s):  
L. D. Spate ◽  
K. A. Walker ◽  
C. E. McHughes ◽  
R. S. Prather
Keyword(s):  
Embryo Culture ◽  
Culture Medium ◽  
Culture Media ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Blastocyst Stage ◽  
Differential Staining ◽  
Low Density ◽  
Cell Stage ◽  
Defined Culture

Embryo culture media typically contain undefined biologicals such as BSA. Our goal is to develop chemically defined culture media that are based on the biology and physiology of the embryo. To that end we evaluated the presence of message in embryos at various stages of development and determined that the message for the low density lipoprotein receptor (LDLR) increased from the germinal vesicle and 4-cell stage to the blastocyst stage of porcine embryogenesis. Thus, this study was conducted to determine if the addition of low density lipoprotein (LDL) would enhance the development and quality of in vitro produced porcine embryos in an already chemically defined culture medium. Slaughterhouse ovaries were aspirated, cumulous–oocyte complexes (COC) identified, and the COC were matured for 42 h in M199 base medium supplemented with EGF, FSH, and LH. Metaphase II oocytes were then selected. Fertilization was then preformed in modified Tris buffered medium and cocultured with 0.25 � 106/mL frozen thawed porcine semen for 5 h. The presumptive zygotes were then transferred to either porcine zygote medium with 0.3% BSA or 0.1% PVA (PZM3, PZM4). After 28 h, cleaved embryos were then sorted into six treatment groups (1. PZM3, 2. PZM3 + 20 µg mL–1 LDL, 3. PZM4, 4. PZM4 + 10 µg mL–1 LDL, 5. PZM4 + 20 µg mL–1 LDL, 6. PZM4 + 50 µg mL–1 LDL). The embryos were cultured in 5%O2 5%CO2 90%N until day 7. The percentage of development to the blastocyst stage was determined and analyzed with the SAS Proc GENMOD Procedure (a–cP ≤ 0.05). The percentage blastocyst was 51.3 � 0.09a, 51.6 � 0.09a, 33.1 � 0.99c, 35.8 � 0.09c, 36.9 � 0.09c, and 41.3 � 0.06b, for treatments 1–6, respectively. Culture in PZM4 (without BSA) significantly reduced development. However, addition of 50 µg mL–1 of LDL to PZM4 improved development above PZM4 alone. We interpret these data to indicate that a high concentration of LDL in the PZM4 media did improve embryo development and that LDL could partially substitute for BSA. Differential staining was performed on the blastocysts, and preliminary results suggest that the ICM to trophectoderm ratio in the high LDL treatment group is closer to the ratio found in in vivo produced embryos. This project was supported by USDA CSREES NRI (2006-35203-17282) and Food for the 21st Century.

315 USE OF PERIFOLLICULAR BLOOD FLOW TO PREDICT THE DEVELOPMENTAL COMPETENCE OF BOVINE CUMULUS-OOCYTE COMPLEXES COLLECTED DURING REPEATED OVUM PICKUP SESSIONS ONCE OR TWICE WEEKLY

2009 ◽  
Vol 21 (1) ◽  
pp. 254 ◽  
Author(s):  
A. Hanstedt ◽  
K. Höffmann ◽  
Ä Honnens ◽  
H. Bollwein ◽  
C. Wrenzycki
Keyword(s):  
Blood Flow ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Small Individual ◽  
Color Flow ◽  
Color Flow Imaging ◽  
Significant Difference ◽  
Developmental Rates ◽  
Group 2 ◽  
Group 1

On average, only 20% of the cumulus–oocyte complexes (COC) develop to the blastocyst stage (Merton et al. 2003 Theriogenology 59, 651–674). An increase in the blood supply to individual follicles appears to be associated with follicular growth rates, whereas a reduction seems to be closely related to follicular atresia (Acosta et al. 2003 Reproduction 125, 759–767). The purpose of this study was to determine whether qualitative perifollicular blood flow changes can be used to predict the developmental competence of COC collected during repeated ovum pickup (OPU) sessions once or twice weekly. Lactating Holstein cows (n = 20) were used as oocyte donors. After dominant follicle removal, OPU was performed twice (group 1, for 3 weeks) or once (group 2, for six weeks) weekly employing a 7.5-MHz transducer (GE 8C-RS) of an ultrasound scanner (GE Logiq Book). Follicle size and Doppler characteristics were recorded by transvaginal ultrasonography just before COC collection using color flow imaging. Owing for technical limitations for measurement of blood flow in small individual follicles, only the presence or absence of blood flow was assessed for each follicle. When a clearly visible blue or red spot (blood flow) was detected in the follicle wall, it was considered as a follicle with detectable blood flow. Follicles with or without detectable blood flow from each individual cow were aspirated separately. After morphological classification of COC, standard protocols for IVP were used for embryo production (Wrenzycki et al. 2001 Biol. Reprod. 65, 323–331). Cleavage and blastocyst rates were recorded at Day 3 and Day 8, respectively. In total, 464 (246 with and 218 without detectable blood flow) and 243 (125 with and 118 without detectable blood flow) follicles ≥3 mm were aspirated in group 1 and group 2, respectively. Morphology of the COC was similar in all groups. Developmental rates for COC stemming from follicles with or without detectable blood flow in group 1 did not show differences for cleavage rates, 54.0% (34/63) and 56.7% (45/81), and for blastocyst rates, 25.4% (16/63) and 22.2% (18/83), respectively. In group 2, the cleavage rates were also similar for COC originating from follicles with and without detectable blood flow, 54.3% (25/46) and 51.5% (34/66). However, developmental rates up to the blastocyst stage did show a significant difference, 23.9% (11/46) and 15.2% (10/66) for COC aspirated from follicles with or without detectable blood flow (P ≤ 0.05). These results show that using COC originating from follicles with detectable perifollicular blood flow collected once weekly may have a higher developmental competence compared to those from follicle without detectable blood flow. Within the detection limits of this study, differences in perifollicular blood flow during repeated OPU sessions once weekly were predictive of oocyte competence. Ruthe Research Farm, Germany, for providing the animals; Masterrind GmbH, Germany, for donation of the semen; and the HW Schaumann Stiftung for financial support.

120 EFFECT OF INDIVIDUAL CULTURE SYSTEM USING WOW OR CELL-TAK ON DEVELOPMENT OF IN VITRO-PRODUCED BOVINE EMBRYOS

2009 ◽  
Vol 21 (1) ◽  
pp. 160
Author(s):  
S. Matoba ◽  
P. Lonergan
Keyword(s):  
Embryo Culture ◽  
Culture System ◽  
Basal Medium ◽  
Bovine Embryos ◽  
Paracrine Effects ◽  
Individual Culture ◽  
Cell Adhesive ◽  
Developmental Rates ◽  
One Way Anova

The culture of embryos individually in vitro is generally associated with poorer developmental rates. However, the ability to do this successfully would greatly facilitate studies where identification of individual embryos, or the embryos from a particular donor, is necessary. The objective of this study was to examine the effect of culture system on the development of individual IVP bovine embryos. Presumptive zygotes (n = 1301, 6 replicates), produced by IVM/IVF, were used. The aim of Experiment 1 was to compare development of bovine embryos in SOF or CR1aa supplemented with 5% FCS. Zygotes were cultured in droplets under oil as follows: (i) 20/25 μL, (ii) 20/100 μL or (iii) 20/100 μL individually in the Well of the Well (WOW) system (Vajta et al. 2000 Mol. Reprod. Dev. 55, 254–264). Twenty WOW were prepared in a 100 μL droplet of medium under oil using a sterile rod. The aim of Experiment 2 was to compare development of embryos cultured in groups but individually identifiable on the cell adhesive Cell-Tak (Stokes et al. 2005 Dev. Biol. 284, 62–71) or in the WOW system. Zygotes were cultured as follows: (i) 20/20 μL, (ii) 20/20 μL with Cell-Tak, (iii) 20/100 μL with Cell-Tak or (iv) 20/100 μL in WOW. A drop of Cell-Tak (1 μL/20 μL medium) was placed on the base of the dish, dried for 20 min, washed with sterile water and dried completely. Once dried, the area was covered with 10 μL of FCS-free medium and groups of 20 zygotes were placed on the Cell-Tak in a 5 × 4 grid formation a maximum of 160 μm apart. Then, an additional 10 μL or 90 μL medium supplemented with FCS was added to give a final volume of 20 or 100 μL. Cleavage and blastocyst rates were assessed on Day 2 and Days 7–9, respectively. Data (means ± SE) were analyzed by one way ANOVA. In Experiment 1, there were no differences between SOF and CR1aa with respect to culture of embryos individually in WOW (P > 0.05); therefore, SOF was used as the basal medium for Experiment 2. There were no differences (P > 0.05) between the cleavage and blastocyst rate among drop sizes and individual culture systems; individual culture, irrespective of the system used (Cell-Tak or WOW), resulted in the similar developmental rates to the control. In conclusion, individual embryo culture offers the opportunity to study embryo development in a more powerful manner. Furthermore, the use of the cell adhesive Cell-Tak may be more practical because it removes the potential variability associated with well dimensions in the WOW system and may improve any potential paracrine effects during embryo culture. Further studies are required to establish the viability of such embryos after transfer. Table 1.Effect of individual culture system on development of IVP bovine embryos Supported by Science Foundation Ireland.

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