scholarly journals Embryo transfer as a tool for improving fertility of heat-stressed dairy cattle

2007 ◽  
Author(s):  
Peter J. Hansen ◽  
Amir Arav
Keyword(s):  
Elevated Temperature ◽  
Heat Shock ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Caspase 3 ◽  
Culture Conditions ◽  
Caspase Activity ◽  
Lactating Cows ◽  
Selection Of

The overall objective of the current proposal is to develop procedures to improve the pregnancy rate achieved following transfer of fresh or cryopreserved embryos produced in the laboratory into heat-stress recipients. The overall hypothesis is that pregnancy rate in heat-stressed lactating cows can be improved by use of embryo transfer and that additional gains in pregnancy rate can be achieved through development of procedures to cryopreserve embryos, select embryos most likely to establish and maintain pregnancy after transfer, and to enhance embryo competence for post-transfer survival through manipulation of culture conditions. The original specific objectives were to 1) optimize procedures for cryopreservation (Israel/US), 2) develop procedures for identifying embryos with the greatest potential for development and survival using the remote monitoring system called EmbryoGuard (Israel), 3) perform field trials to test the efficacy of cryopreservation and the EmbryoGuard selection system for improving pregnancy rates in heat-stressed, lactating cows (US/Israel), 4) test whether selection of fresh or frozen-thawed blastocysts based on measurement of group II caspase activity is an effective means of increasing survival after cryopreservation and post-transfer pregnancy rate (US), and 5) identify genes in blastocysts induced by insulin-like growth factor-1 (IGF-1) (US). In addition to these objectives, additional work was carried out to determine additional cellular determinants of embryonic resistance to heat shock. There were several major achievements. Results of one experiment indicated that survival of embryos to freezing could be improved by treating embryos with cytochalasin B to disrupt the cytoskeleton. An additional improvement in the efficacy of embryo transfer for achieving pregnancy in heat-stressed cows follows from the finding that IGF-1 can improve post-transfer survival of in vitro produced embryos in the summer but not winter. Expression of several genes in the blastocyst was regulated by IGF-1 including IGF binding protein-3, desmocollin II, Na/K ATPase, Bax, heat shock protein 70 and IGF-1 receptor. These genes are likely candidates 1) for developing assays for selection of embryos for transfer and 2) as marker genes for improving culture conditions for embryo production. The fact that IGF-1 improved survival of embryos in heat-stressed recipients only is consistent with the hypothesis that IGF-1 confers cellular thermotolerance to bovine embryos. Other experiments confirmed this action of IGF-1. One action of IGF-1, the ability to block heat-shock induced apoptosis, was shown to be mediated through activation of the phosphatidylinositol 3-kinase pathway. Other cellular determinants of resistance of embryos to elevated temperature were identified including redox status of the embryo and the ceramide signaling pathway. Developmental changes in embryonic apoptosis responses in response to heat shock were described and found to include alterations in the capacity of the embryo to undergo caspase-9 and caspase-3 activation as well as events downstream from caspase-3 activation. With the exception of IGF-1, other possible treatments to improve pregnancy rate to embryo transfer were not effective including selection of embryos for caspase activity, treatment of recipients with GnRH.and bilateral transfer of twin embryos. In conclusion, accomplishments achieved during the grant period have resulted in methods for improving post-transfer survival of in vitro produced embryos transferred into heat-stressed cows and have lead to additional avenues for research to increase embryo resistance to elevated temperature and improve survival to cryopreservation. In addition, embryo transfer of vitrified IVF embryos increased significantly the pregnancy rate in repeated breeder cows.

scholarly journals Should rescue ICSI be re-evaluated considering the deferred transfer of cryopreserved embryos in in-vitro fertilization cycles? A systematic review and meta-analysis

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Alessio Paffoni ◽  
Marco Reschini ◽  
Valerio Pisaturo ◽  
Cristina Guarneri ◽  
Simone Palini ◽  
...  
Keyword(s):  
In Vitro Fertilization ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Implantation Rate ◽  
Clinical Pregnancy ◽  
Frozen Embryo Transfer ◽  
Fertilization Failure ◽  
Vitro Fertilization ◽  
Rescue Icsi

Abstract Background Total fertilization failure represents a particularly frustrating condition for couples undergoing in vitro fertilization. With the aim of reducing the occurrence of total fertilization failure, intracytoplasmic sperm injection (ICSI) has become the first choice over conventional in vitro fertilization (IVF) procedures although evidence of improved results is still debated and its use in couples without male factor infertility is not recommended. Among the strategies potentially useful to promote the use of conventional IVF, we herein call attention to the late rescue ICSI, which consists in performing ICSI after 18–24 h from conventional insemination on oocytes that show no signs of fertilization. This treatment has however been reported to be associated with a low success rate until recent observations that embryos derived from late rescue ICSI may be transferred after cryopreservation in a frozen-thawed cycle with improved results. The aim of the present study was to assess whether frozen embryos deriving from rescue ICSI performed about 24 h after conventional IVF may represent a valuable option for couples experiencing fertilization failure. Methods A systematic review on the efficacy of late rescue ICSI was performed consulting PUBMED and EMBASE. Results Including twenty-two original studies, we showed that clinical pregnancy rate per embryo transfer and implantation rate obtainable with fresh embryo transfers after rescue ICSI are not satisfactory being equal to 10 and 5%, respectively. The transfer of cryopreserved rescue ICSI embryos seems to offer a substantial improvement of success rates, with pregnancy rate per embryo transfer and implantation rate equal to 36 and 18%, respectively. Coupling rescue ICSI with frozen embryo transfer may ameliorate the clinical pregnancy rate for embryo transfer with an Odds Ratio = 4.7 (95% CI:2.6–8.6). Conclusion Results of the present review support the idea that r-ICSI coupled with frozen embryo transfer may overcome most of the technical and biological issues associated with fresh transfer after late r-ICSI, thus possibly representing an efficient procedure for couples experiencing fertilization failure following conventional IVF cycles. Trial registration Prospero registration ID: CRD42021239026.

scholarly journals 324SPHINGOSINE-1-PHOSPHATE PROTECTS CULTURED BOVINE OOCYTES FROM PHYSIOLOGICALLY RELEVANT THERMAL STRESS

2004 ◽  
Vol 16 (2) ◽  
pp. 282 ◽  
Author(s):  
Z. Roth ◽  
P.J. Hansen
Keyword(s):  
Thermal Stress ◽  
Heat Shock ◽  
Blastocyst Stage ◽  
Caspase Activity ◽  
Blastocyst Development ◽  
Cleavage Rate ◽  
Developmental Potential ◽  
Oocyte Competence ◽  
Cell Death Pathway

Sphingosine-1-phosphate (S1P) is a sphingolipid metabolite that can block the sphingomyelin cell-death pathway by suppressing ceramide-induced apoptosis. The present study was performed to test whether S1P protects oocytes from heat shock during in vitro maturation. Cumulus-oocyte complexes obtained by slicing follicles were placed in maturation medium with or without 50nM S1P and cultured at 38.5°C (CON) or 41°C (41C) for the first 12h of maturation. Incubation during the last 10h of maturation (22-h total maturation time), fertilization, and embryonic development were performed at 38.5°C and 5% (v/v) CO2. Blastocyst development was recorded at 8 days post-insemination (dpi) and activity of group II caspases in 8-day blastocysts was determined using a fluoroprobe, PhiPhiLux-G1D2 (OncoImmunin, Gaithersburg, MD, USA). Data were analysed by least-squares ANOVA with the GLM procedure of SAS. Percentage data were subjected to arcsin transformation before analysis. Exposure of oocytes to thermal stress during the first 12h of maturation reduced cleavage rate (P<0.01) and the number of oocytes developing to the blastocyst stage (P<0.04). There was a temperature x S1P interaction for cleavage rate (P<0.03) because S1P blocked effects of thermal stress on cleavage rate. Without S1P, the percentage of oocytes that cleaved by 3 dpi were 83.6±2.7% and 65.8±2.7% for CON and 41C, respectively. In the presence of S1P, percent cleavage was 86.7±2.7% and 83.9±2.7% for CON and 41C, respectively. There was a trend (P=0.06) for a temperature x S1P interaction for percent oocytes developing to blastocyst stage because S1P blocked effects of heat shock on development. Without S1P, the percentages of oocytes that developed to the blastocyst stage were 28.7±3.0% and 15.2±3.0% for CON and 41C, respectively. In the presence of S1P, percent blastocysts were 24.3±3.4% and 23.9±3.0% for CON and 41C, respectively. When development was expressed as percentage of cleaved embryos, however, there were no effects of temperature, S1P, or temperature x S1P on percent development to the blastocyst stage. Blastocyst caspase activity was not affected by temperature or S1P. In summary, exposure to physiologically relevant thermal stress during the first 12h of maturation has a deleterious effect on oocyte competence and this effect can be reduced by S1P. The fact that heat shock reduced the percentage of oocytes but not the percentage of cleaved embryos that became blastocysts suggests that oocytes that survive effects of heat shock and cleave have normal potential to develop to the blastocyst stage. Moreover, since heat shock did not affect caspase activity, it is likely that blastocysts from heat-shocked oocytes have normal developmental potential, at least as determined by caspase activity. Support: BARD FI-330-2002 and USDA Grants 2002-35203-12664 and 2001-52101-11318.

scholarly journals Effect of the trends of estradiol level on the outcome of in vitro fertilization-embryo transfer with antagonist regimens: a single center retrospective cohort study

2021 ◽  
Author(s):  
Chun-Xiao Wei ◽  
liang zhang ◽  
Cong-Hui Pang ◽  
Ying-Hua qi ◽  
Jian-Wei Zhang
Keyword(s):  
In Vitro Fertilization ◽  
Pregnancy Rate ◽  
Pregnancy Outcome ◽  
Embryo Transfer ◽  
Ovarian Response ◽  
Vitro Fertilization ◽  
The Relationship ◽  
Estradiol Levels

Abstract BackgroundThe outcome of in vitro fertilization-embryo transfer is often determined according to follicles and estradiol levels following gonadotropin stimulation. However, there is no accurate indicator to predict pregnancy outcome, and it has not been determined how to choose subsequent drugs and dosage based on the ovarian response. This study aimed to make timely adjustments to follow-up medication to improve clinical outcomes based on the potential value of estradiol growth rate. MethodsSerum estradiol levels were measured on the day of gonadotrophin treatment (Gn0), four days later (Gn4), seven days later (Gn7), and on the trigger day (HCG). The ratio was used to determine the increase in estradiol levels. According to the ratio of estradiol increase, the patients were divided into four groups: group A1 (Gn4/Gn0≤6.44), group A2 (6.44˂Gn4/Gn0≤10.62), group A3 (10.62˂Gn4/Gn0 ≤21.33), and group A4 (Gn4/Gn0>21.33); group B1 (Gn7/Gn4≤2.39), group B2 (2.39˂Gn7/Gn4≤3.03), group B3 (3.03˂Gn7/Gn4≤3.84), and group B4 (Gn7/Gn4>3.84). We analyzed and compared the relationship between data in each group and pregnancy outcome. ResultsIn the statistical analysis, the estradiol levels of Gn4 (P = 0.029, P = 0.042), Gn7 (P< 0.001, P = 0.001), and HCG (P< 0.001, P = 0.002), as well as the ratios of Gn4/Gn0 (P = 0.004, P = 0.006), Gn7/Gn4 (P = 0.001, P = 0.002), and HCG/Gn0 (P< 0.001, P< 0.001) both had clinical guiding significance, and the lower one significantly reduced the pregnancy rate. The outcomes were positively linked to groups A (P = 0.040, P = 0.041) and B (P = 0.015, P = 0.017). The logistical regression analysis revealed that group A1 (OR = 0.440 [0.223–0.865]; P = 0.017, OR = 0.368 [0.169–0.804]; P = 0.012) and B1 (OR = 0.261 [0.126–0.541]; P< 0.001, OR = 0.299 [0.142–0.629]; P = 0.001) had opposite influence on outcomes. ConclusionMaintaining a serum estradiol increase ratio at least above 2.39 on Gn7/Gn4 may result in a higher pregnancy rate. When estradiol growth is not ideal, gonadotrophin dosage should be adjusted appropriately to ensure the desired outcome.

Venular endothelial cells from bovine heart

1988 ◽  
Vol 254 (6) ◽  
pp. H1211-H1217 ◽  
Author(s):  
M. E. Schelling ◽  
C. J. Meininger ◽  
J. R. Hawker ◽  
H. J. Granger
Keyword(s):  
Endothelial Cells ◽  
In Vitro Model ◽  
Protein Transport ◽  
Culture Conditions ◽  
Support Cell ◽  
Vitro Model ◽  
Microvascular Cells ◽  
Selection Of ◽  
Coronary Angiogenesis

Coronary venular endothelial cells were isolated by a bead-perfusion technique that allowed the selection of endothelial cells from venules of a specific size. Culture conditions for the microvascular cells were established. Cells grew well in supplemented Dulbecco's modified Eagle's medium. The effect of various substrata on the proliferation of the venular endothelial cells was determined. Matrigel, gelatin, and fibronectin supported high levels of proliferation. Cell shape was correlated with ability of the substratum to support cell proliferation. Cells exhibiting a broad, flattened morphology achieved high levels of proliferation. The formation of vessel meshworks by the coronary venular endothelial cells provides an in vitro model for the study of coronary angiogenesis. Confluent monolayers of these cells can be utilized to examine mechanisms of water and protein transport across coronary venules.

scholarly journals Three light-inducible heat shock genes of Chlamydomonas reinhardtii.

1989 ◽  
Vol 9 (9) ◽  
pp. 3911-3918 ◽  
Author(s):  
E D von Gromoff ◽  
U Treier ◽  
C F Beck
Keyword(s):  
Thermal Stress ◽  
Elevated Temperature ◽  
Heat Shock ◽  
Chlamydomonas Reinhardtii ◽  
Heat Shock Gene ◽  
Mrna Levels ◽  
Heat Shock Genes ◽  
Drastic Increase ◽  
Shock Gene

Genomic clones representing three Chlamydomonas reinhardtii genes homologous to the Drosophila hsp70 heat shock gene were isolated. The mRNAs of genes hsp68, hsp70, and hsp80 could be translated in vitro into proteins of Mr 68,000, 70,000, and 80,000, respectively. Transcription of these genes increased dramatically upon heat shock, and the corresponding mRNAs rapidly accumulated, reaching a peak at around 30 min after a shift to the elevated temperature. Light also induced the accumulation of the mRNAs encoded by these heat shock genes. A shift of dark-grown cells to light resulted in a drastic increase in mRNA levels, which reached a maximum at around 1 h after the shift. Thus, in Chlamydomonas, expression of hsp70-homologous heat shock genes appears to be regulated by thermal stress and light.

77 Monozygotic Twin Calves Production by Blastomere Separation Technique with Commercial Well-of-the-Well Culture Dish

2018 ◽  
Vol 30 (1) ◽  
pp. 177
Author(s):  
Y. Hashiyada ◽  
Y. Aikawa ◽  
H. Matsuda ◽  
T. Yamanouchi ◽  
Y. Goto ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Twin Pregnancy ◽  
Small Body ◽  
Fetal Loss ◽  
Monozygotic Twin ◽  
Gestation Length ◽  
Culture Dish ◽  
Significant Difference

Monozygotic twin bovine embryos can be produced by blastomere separation of 2-cell embryos and commercial well-of-the-well (WOW) culture dish (Hashiyada et al. 2016 Reprod. Fertil. Dev. 28, 178) obtaining 60% and 48% of blastocyst formation and monozygotic blastocyst pairs, respectively. The present study was conducted to evaluate the fertility of blastocysts derived from this production system in Japanese Black beef cattle. Embryos were produced using oocytes collected by ovum pick-up technique. TCM-199 supplemented with 5% calf serum (CS), Brackett-Oliphant solution supplemented with 10 mg mL−1 BSA, and CR1aa containing 5% CS, were used for each culture step: in vitro maturation, fertilization, and culture (IVM,IVF, and IVC). Two-cell stage embryos were obtained 24 to 27 h post-insemination. Zonae pellucidae were removed by exposure to 0.25% pronase. Then, embryos were separated into blastomeres by gentle pipetting in IVC medium. Each blastomere was introduced into a single conical microwell of 25 wells, each having a diameter and depth of ~287 μm and 168 μm (Dai Nippon Printing, Tokyo, Japan). Blastomeres in wells were cultured covered with a droplet of 2.5 μL of IVC medium/well. The developed blastocysts in pairs on 7 days post-insemination were used for transfer. Single embryos of monozygotic twin embryos were transferred to Japanese Black cattle with a generally small body frame to produce twin calves from a set of recipients. Twin embryos were transferred in pairs to unilateral of uterus of non-lactating Holstein cows. Pregnancy and twin pregnancy were determined at 30 days of gestation by ultrasonography and were reconfirmed at 60 days with detection of fetal loss. Statistical significance was analysed by Fisher’s exact test. There was no significant difference in pregnancy rate or twin pregnancy rate between single embryo transfer (7/14, 50% and 2/7, 28.6%) and twin embryo transfer (9/21, 42.9% and 4/21, 19%). In either transfer method, fetal loss was not observed in diagnosis carried out at 60 days by ultrasonography. To date, 2 pairs of twin calves have been obtained from twin pregnant cows by twin embryo transfer within the normal range of gestation length (286 and 288 days) and birth weight (31-40 kg). These results indicate that blastocysts developed from blastomeres separated from 2-cell embryos by culturing with commercial WOW culture dish had fertility similar to that of intact embryos derived from standard in vitro culture and further demonstrate the possibility of production of normal twin calves.

Effect of plasma urea concentration at the time of insemination or embryo transfer on pregnancy rate in cattle

2001 ◽  
Vol 26 (2) ◽  
pp. 367-370 ◽  
Author(s):  
V.P. Gath ◽  
J. Fahey ◽  
S.E.M. Snijders ◽  
D. O'Callaghan
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
High Energy ◽  
Subsequent Pregnancy ◽  
Plasma Urea ◽  
Retrospective Comparison ◽  
Significant Difference ◽  
Uterine Environment ◽  
Plasma Urea Concentration

AbstractPlasma urea concentrations have been used as a diagnostic tool in the investigation of reproductive performance in cattle. Data were compiled from three recent studies on bovine fertility and a retrospective comparison of plasma urea concentrations was made between those animals that conceived to an insemination or embryo transfer. In studies I and 2 plasma urea concentrations around the time of insemination were determined. Pregnancies were diagnosed using ultrasonography 35 days later. There was no significant difference between the mean plasma urea concentrations around the time of insemination in the cattle subsequently diagnosed pregnant or not pregnant. In study 3, in vitro produced good quality embryos were transferred into three groups of beef heifers. The three groups were allocated to diets of high energy / high urea, high energy / no urea and low energy / high urea. The plasma urea concentrations at the time of embryo transfer were different between the three groups. However, the pregnancy rates 28 days post transfer, were not significantly different between the three groups. This suggests that the previously reported effects of high protein diets on fertility are not solely due to disruptive effects on the uterine environment. The main effect of urea on fertility may be on oocyte development within the follicle. Overall, these results indicate that measurement of plasma urea concentrations in individual animals around the time of insemination or embryo transfer is not a useful predictor of subsequent pregnancy rate.

Acupuncture Prior to and at Embryo Transfer in An Assisted Conception Unit – a Case Series

2006 ◽  
Vol 24 (1) ◽  
pp. 23-28 ◽  
Author(s):  
David Johnson
Keyword(s):  
Success Rate ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Assisted Reproduction ◽  
Case Series ◽  
In Vitro Fertilisation ◽  
Assisted Conception ◽  
Before And After ◽  
In Pregnancy

Over a period of three years, acupuncture was offered to patients entering assisted reproduction therapy. Acupuncture sessions were given at varying, but usually weekly, intervals during the in vitro fertilisation (IVF) cycle, and immediately before and after embryo transfer. Twenty two patients (average age 36.2 years) were treated over a total of 26 IVF cycles and 15 pregnancies were achieved, as determined by presence of foetal heartbeat on ultrasound at four weeks post embryo transfer. This was a success rate of 57.7% compared with 45.3% for patients in the IVF unit not treated with acupuncture (P>0.05). Relaxing effects were noted following acupuncture and it is speculated that this may have contributed to the increase in pregnancy rate for the acupuncture group.

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