126 THE EFFECT OF FORSKOLIN ON IN VITRO PRODUCED BRAHMAN-SIRED BOVINE EMBRYOS

2009 ◽  
Vol 21 (1) ◽  
pp. 163 ◽  
Author(s):  
J. H. Pryor ◽  
J. A. Trant ◽  
C. B. Ponchirolli-Schneider ◽  
C. R. Looney ◽  
C. R. Long ◽  
...  
Keyword(s):  
Treatment Group ◽  
Uv Light ◽  
Nile Red ◽  
Total Cell ◽  
Bovine Embryos ◽  
Treatment Groups ◽  
Intracellular Lipids ◽  
Lipolytic Effect ◽  
Development Rates

Forskolin (Colforsin) is a lipolytic agent that can be used to reduce intracellular lipids within in vitro produced (IVP) porcine embryos (Men et al. 2006 Theriogenology 66, 2008–2016). Lowering lipids within bovine embryos has shown to decrease sensitivity to cryopreservation. The objective of this preliminary experiment was to determine developmental differences and lipolytic effect on bovine IVP embryos exposed to 10 or 40 μm forskolin. Bovine oocytes (obtained from an abattoir) were fertilized with frozen/thawed Brahman semen (Day 0) and cultured in G1.5/G2.5 medium supplemented with 8 mg mL–1 BSA (Vitrolife, Englewood, CO, USA). On Day 6 post-fertilization, a total of 352 viable embryos were randomly submitted to 3 treatment groups; Control (no treatment, n = 116), 10 μm (n = 122) and 40 μm (n = 114) forskolin (Sigma, St. Louis, MO, USA) in G2.5 medium for 24 h. On Day 7, embryos were washed in holding medium (Vigro Holding Plus, Bioniche, Pullman, WA, USA). From each treatment group, a randomized half was cultured 72 h in G2.5 and assessed for hatched blastocyst rates (development), with the balance stained on Day 7 in Hoechst 33342 (2.5 μg mL–1) under UV light for total cell counts before being fixed/stained in Nile red (1 μg mL–1). Nile red stained embryos were mounted on glass slides with cover slips gently applied over each embryo. Embryos were photographed under UV light using the proper excitation filters. The area measurements of compact morula and blastocysts did not include the zona pellucida. Nile red units (NRU) were measured with computer software Image J (www.rbsweb.nih.gov) from 0 to 255 shades/pixel (0 = no lipids; 255 = highest lipid accrual). Each image was adjusted for variation in embryo size. Student’s t-test was used for statistical analysis. There was no difference (P > 0.05) between development rates for control, 10 μm and 40 μm forskolin (62%, 67% and 65%, respectively). Mean NRU by total cell numbers were calculated per embryo for each treatment group: control, 10 μm and 40 μm with the resulting means being 72.4 ± 5.0, 63.1 ± 5.1 and 66.6 ± 4.8 respectively. With treatment groups combined by embryo stage, compact morula tended to exhibit a higher mean NRU than blastocysts (78.6 ± 6.8 to 64.7 ± 3.1, respectively, P = 0.07). In conclusion, forskolin did not significantly affect embryo development rates or lipid content as measured by Nile Red staining. Compact morula tended to yield a higher NRU mean than blastocysts indicating an elevation in intracellular lipids. Unlike pig IVP embryos exposed to forskolin, forskolin failed to show a significant decrease in intracellular lipids within bovine IVP embryos. However, further research is in progress to test forskolin’s lipolytic effect on cryopreservation of in vitro and in vivo produced bovine embryos. The authors acknowledge support from the American Brahman Breeders Association and Dr. Moisés Barceló Fimbres.

scholarly journals 136 EVIDENCE OF A DIRECT EFFECT OF P4 ON IVF-DERIVED BOVINE 8-CELL 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 ◽  
...  
Keyword(s):  
Embryo Development ◽  
Direct Effect ◽  
Blastocyst Stage ◽  
Control Group ◽  
Bovine Embryo ◽  
Bovine Embryos ◽  
Direct Role ◽  
Treatment Groups ◽  
And Control

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.

334 EFFECT OF INSULIN ON IN VITRO MATURATION OF CANINE OOCYTES

2006 ◽  
Vol 18 (2) ◽  
pp. 275
Author(s):  
H. S. Lee ◽  
Y. I. Seo ◽  
X. J. Yin ◽  
S. G. Cho ◽  
I. H. Bae ◽  
...  
Keyword(s):  
In Vitro Maturation ◽  
Uv Light ◽  
Cumulus Cells ◽  
Oocyte Activation ◽  
Cell Stage ◽  
Oocyte Competence ◽  
Treatment Groups ◽  
Maturation Medium ◽  
Oviduct Fluid

In spite of our increased knowledge of in vitro oocyte maturation techniques, the success rate of obtaining mature canine oocytes in vitro remains very low compared with that for other domestic animals. The inefficient rate of meiotic resumption of canine oocytes is probably due to both the unique reproductive cycle and inappropriate in vitro maturation (IVM) medium. In an unpublished experiment, we found that the concentration of insulin was higher in estrus bitch serum (EBS; 8833 pg/mL) than in dog follicular fluid (DFF; preovulatory follicle, 122 pg/mL), which implies its possible role in the acquisition of oocyte competence. Therefore, in the present study we investigated the effects of supplementing the IVM medium with insulin on the incidence of maturation to metaphase II. Ovaries were collected from various stages of the estrous cycle by ovariohysterectomy, and oocytes with two or more intact cumulus layers and with a diameter >110 �m were selected and used for IVM. Oocytes were cultured in modified synthetic oviduct fluid (2004 Reprod. Nutr. Dev. 44, 105-109) supplemented with 10% EBS, 20 �g/mL estradiol, and different concentrations of insulin (0, 10, 100, or 1000 ng/mL) at 38.5�C, 5% CO2 in air. After 72 h, cumulus cells were removed from around oocytes using a small glass pipette. Denuded oocytes were fixed in 3.7% paraformaldehyde supplemented with 10 �g/mL Hoechst 33342 at room temperature for 40 min. Nuclear status was observed under UV light using a fluorescence microscope. The percentage of oocytes at the metaphase II stage was not different among the four groups 6.8, 1.8, 5.4, and 2.1% in the control, 10, 100, and 1000 ng/mL insulin groups, respectively. The incidence of oocytes with pronuclear-like structures or cleaving beyond the two-cell stage was not significant higher in the 10 and 100 ng/mL insulin treatment groups than in the control and 1000 ng/mL insulin groups 20.0 and 19.6% vs. 6.8 and 6.4%, respectively. These results indicate that the addition of insulin to the in vitro maturation medium of dog oocytes had no effect on the incidence of meiotic maturation to metaphase II, nor did it affect the frequency of occurrence of spontaneous oocyte activation.

50 EFFECT OF AGGREGATION OR FUSION ON DEVELOPMENT AND CELL NUMBER OF BOVINE EMBRYOS PRODUCED BY HANDMADE CLONING AND PARTHENOGENESIS

2008 ◽  
Vol 20 (1) ◽  
pp. 105
Author(s):  
E. S. Ribeiro ◽  
R. P. C. Gerger ◽  
L. U. Ohlweiler ◽  
I. Ortigari Jr ◽  
F. Forell ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Chemical Activation ◽  
Primary Cultures ◽  
Cell Number ◽  
Total Cell ◽  
Bovine Embryos ◽  
In Vitro Development ◽  
Vitro Development ◽  
Handmade Cloning

Cloning by somatic cell nuclear transfer has been associated with developmental abnormalities, with the level of heteroplasmy imposed by cell fusion being one of many potential determining factors. As the cytoplast exerts a key role in nuclear reprogramming, embryo aggregation is an alternative to minimize such negative effects during cloning. The aim of this study was to determine the effect of fusion of hemi-cytoplasts or aggregation of hemi-embryos on in vitro development and cell number of clone and parthenote embryos. Bovine cumulus–oocyte complexes (COCs) from slaughterhouse ovaries, after 17 h of IVM, were used for the production of parthenotes by chemical activation, and clone embryos by handmade cloning (HMC) (Vajta et al. 2003 Biol. Reprod. 68, 571–578). Following cumulus and zona removal, oocytes were manually bisected, followed by segregation of nucleated and enucleated hemi-cytoplasts by fluorescence using Hoechst stain. One or two enucleated hemi-cytoplasts were paired with an adult skin somatic cell from primary cultures (>90% confluence) and fused using a 25V AC pre-pulse, followed by a single 1.2 kV cm–1 DC pulse for 10 μs. Reconstructed clone structures and groups of zona-intact oocytes and nucleated hemi-cytoplasts were chemically activated in ionomycin and 6-DMAP. Clone and parthenote structures were in vitro-cultured in the WOW system (Vajta et al. 2000 Mol. Reprod. Dev. 55, 256–264) for 7 days, as follows: (G1) clone embryos reconstructed by aggregation of two hemi-embryos per WOW; or (G2) one embryo (two hemi-cytoplasts + cell) perWOW; and parthenote embryos composed of (G3) zona-intact oocytes cultured in wells; or aggregation of one (G4), two (G5), three (G6), or four (G7) nucleated hemi-cytoplasts per WOW. Fusion, cleavage (Day 2), and blastocyst (Day 7) rates, evaluated on a per WOW basis, were compared by the chi-square test (8 replications). Total cell number estimated by fluorescence (Hoechst stain) in blastocysts was analyzed by the Student t-test. Fusion rates of one hemi-cytoplast + cell (G1; 275/592, 46.5%) were lower than for two hemi-cytoplasts + cell (G2; 264/337, 78.3%). Cleavage rates were lower in G1 and G4 and higher in G6 and G7 than G2 and G3. A significant linear increase in blastocyst rates was observed in G5, G6, and G7. Total cell numbers were lower in parthenotes than in clones, except in G6 and G7. The lower fusion and cleavage rates after the aggregation of two clone hemi-embryos (G1) caused nearly a 50% reduction in the overall cloning efficiency. In addition, the aggregation of parthenogenetic hemi-embryos increased cleavage and blastocyst rates and cell number. However, aggregation of hemi structures did not improve blastocyst yield or cell number on a hemi-cytoplast basis. Table 1. In vitro development of parthenote or clone bovine embryos This work was supported by funding from CAPES/Brazil.

166 EFFECT OF INDIVIDUAL CULTURE SYSTEM ON IN VITRO DEVELOPMENT OF IN VITRO-MATURED - IN VITRO-FERTILIZED BOVINE EMBRYOS

2012 ◽  
Vol 24 (1) ◽  
pp. 195
Author(s):  
R. Nishii ◽  
K. Imai ◽  
H. Koyama ◽  
O. Dochi
Keyword(s):  
Culture System ◽  
Calf Serum ◽  
Control Culture ◽  
Total Cell ◽  
Bovine Embryo ◽  
Bovine Embryos ◽  
Culture Systems ◽  
Individual Culture ◽  
Single Culture

An individual in vitro culture system for bovine embryo needs to be developed for the study of embryo developmental competence. The objective of this study was to examine the effect of individual culture systems on the development of in vitro-matured–in vitro-fertilized bovine embryos. Two individual culture systems were compared. Cumulus–oocyte complexes (COC) were collected by aspiration of ovarian follicles (diameter, 2 to 5 mm) obtained from a local abattoir. The COC were matured in TCM-199 supplemented with 5% calf serum and 0.02 AU mL–1 of FSH. Groups of 20 COC were incubated in 100-μL droplets of IVM media at 38.5°C under an atmosphere of 5% CO2 for 20 h. After 18 h of gamete co-culture (3 × 106 sperm mL–1), the presumptive zygotes were cultured in CR1aa medium supplemented with 5% calf serum at 38.5°C under an atmosphere of 5% CO2, 5% O2 and 90% N2 for 9 days (fertilization = Day 0). The presumptive zygotes were randomly assigned to 1 of the following 3 treatments: single culture (1 zygote was cultured in a 5-μL droplet), well-of-the-well (WOW; Sugimura et al. 2010 Biol. Reprod. 83, 970–978) culture (25 zygotes were cultured individually in each 125-μL droplet) and control culture (25 zygotes were cultured in a 125-μL droplet). Embryo development was evaluated for cleavage and blastocyst rates, on Day 2 and Day 7 to 9 after IVF, respectively. The rates of development up to the blastocyst stage and total cell number in the blastocysts, determined by an air-drying method, were investigated. The cleavage and blastocyst rates were analysed by the chi-square test and the total cell numbers were analysed by ANOVA. The cleavage rates were significantly higher in the control and WOW groups than in the single-culture group (P < 0.01) and the blastocyst rates were significantly lower in the single-culture group than in the control culture group (P < 0.05; Table 1). The total cell numbers (mean ± s.d.) of blastocysts did not significantly differ between the single culture (154.6 ± 21.8), control culture (155.2 ± 22.5) and WOW culture (159.8 ± 27.0) groups. These results indicate that although the blastocyst rate was lower in the single-culture system than in the WOW or group culture system, in vitro-matured–in vitro-fertilized bovine embryos can be cultured using the single-culture system. Moreover, the quality of blastocysts developed by the single-culture system is the same as that of blastocysts developed using the other 2 culture systems. Table 1.Effect of different culture methods for bovine embryo development

1 ARGININE SUPPLEMENTATION IN VITRO INCREASES PORCINE EMBRYO DEVELOPMENT AND AFFECTSmRNA TRANSCRIPT EXPRESSION

2011 ◽  
Vol 23 (1) ◽  
pp. 107 ◽  
Author(s):  
B. K. Bauer ◽  
L. D. Spate ◽  
C. N. Murphy ◽  
R. S. Prather
Keyword(s):  
Treatment Group ◽  
Mrna Expression ◽  
Embryo Development ◽  
Blastocyst Stage ◽  
Sequencing Analysis ◽  
Treatment Groups ◽  
Porcine Embryo ◽  
Arginine Supplementation

In vitro culture systems are suboptimal as compared to in vivo. Previous next-generation sequencing analysis of in vivo fertilized and in vitro cultured (IVC) or in vivo cultured (IVV) porcine blastocyst stage embryos identified an arginine transporter (SLC7A1) expressed 63 fold higher in IVC compared to IVV blastocysts (Bauer et al. 2010 Biol. Reprod. Epub ahead of print). Arginine catabolism may play important roles in placental and conceptus growth and development as it is a substrate for synthesis of nitric oxide synthase and polyamines. The objective of this study was to determine the effects arginine had on both embryo development and mRNA expression in in vitro fertilized embryos. Cumulus–oocyte complexes were matured for 44 h in M199 supplemented with EGF, FSH, and LH. Oocytes with a visible polar body (metaphase II) were selected and fertilized in modified Tris Buffered Medium for 5 h and then placed into one of 5 treatment groups (Porcine Zygote Medium 3 (PZM3) with 0 mM, 0.12 mM (current concentration of arginine in PZM3), 0.36 mM, 0.72 mM, or 1.69 mM arginine). Twenty-eight hours post-fertilization, cleaved embryos were selected and moved into 25 μL drops of respective culture media and cultured to day 6 in 5% CO2, 5% O2, 90% N2 at 38.5°C. To determine the effect arginine had on development the percent of embryos that made it to the blastocyst stage for each treatment group were analysed using PROC GLM in SAS (SAS Institute, Cary, NC). A least significant difference post test comparison was completed to determine if significant differences existed between treatment groups (a,b,cP < 0.05). The percentage of cleaved embryos on Day 6 that developed to blastocyst was 57.2%b,c, 50.2%c, 67.3%a,b, 67.3%a,b, 70.4%a (N = 147, 163, 150, 120, and 134) in 0 mM, 0.12 mM, 0.36 mM, 0.72 mM, and 1.69 mM arginine, respectively. Real-time PCR was then completed to assess the affect arginine supplementation had on SLC7A1 mRNA expression. Three biological replicates, each containing 10 blastocyst pools to ensure enough starting material, were collected for each treatment group. RNA was isolated from each sample and 5 μL was linearly amplified (NuGEN Ovation Pico WTA System) so multiple genes could be compared and then purified using Bio-Rad MicroSpin Columns. Expression levels were calculated relative to the reference sample and the housekeeping gene, YWHAG. The ΔΔCT values were log-transformed and analysed using PROC GLM in SAS. The expression of SLC7A1 mRNA was decreased (P = 0.0006) compared to PZM3 in the 1.69 mM arginine group. These results illustrate the positive effects that additional arginine may be having on porcine embryo development during culture from the 2-cell to the blastocyst stage. Supplementing arginine to a final concentration of 1.69 mM during culture increases development of porcine embryos to blastocyst compared to PZM3 and also decreases the expression of SLC7A1. Evaluation of the transcriptional profile appears to be a good method of letting the embryo tell us what it needs for development, and in this case arginine. Funded by F21C.

94 EFFECTS OF 6- OR 12-HOUR CULTURE IN A Micro Q STRAW INCUBATOR ON DEVELOPMENT OF IN VITRO-PRODUCED BOVINE EMBRYOS

2016 ◽  
Vol 28 (2) ◽  
pp. 177
Author(s):  
C. R. Looney ◽  
J. H. Pryor ◽  
M. Snyder ◽  
A. Ilercil ◽  
C. R. Long
Keyword(s):  
Embryo Transfer ◽  
Uv Light ◽  
Tween 20 ◽  
Treatment Groups ◽  
Cell Counts ◽  
Stage 4 ◽  
Embryo Stage ◽  
Transfer Services ◽  
In Transit

Transporting in vitro-produced (IVP) embryos can be challenging when an embryo transfer destination is more than 6 h away or electricity is not available on site to unload embryos for transfer. The objective of this study was to determine if development rates would be compromised for Day 6.5 IVP embryos when placed in warmed Vigro holding medium (Vetoquinol, Pullman, WA, USA) loaded and plugged into 1/4 cc straws (Professional Embryo Transfer Services, Canton, TX, USA) for a period of either 6 or 12 h in a 38.5°C Micro Q straw block incubator (Micro Q iQ1T 64). Bovine oocytes were shipped and matured in transit from a commercial abattoir (DeSoto Biosciences, Seymour, TN, USA), fertilized (IVF = Day 0) with frozen-thawed semen, and cultured in Bovine Evolve (Zenith Biotech, Guilford, CT, USA) supplemented with 4 mg mL–1 BSA (Probumin, EMD Millipore, Norcross, GA, USA) under oil in a 5% CO2, 5%O2, 90% N2 humidified incubator (Pryor et al. 2011 Theriogenology 75, 24–33). Cleavage rates of 87.7% (664/757) from three replicates produced 273 (36.0%) viable embryos on Day 6.5 post-IVF, which were evenly distributed by IETS stage (4–7) and grade (1 and 2) into three treatment groups (0 = control, 6 or 12 h straw incubation) before in vitro culture for an additional 24 h. For each replicate, the average embryo stage was calculated by multiplying the number of embryos in each treatment by their IETS stage and dividing by total embryos per group. The change in stage for each treatment was calculated by subtracting the initial average stage from the final average stage on Day 8. Grade 1 and 2 embryos at stage 6–8 were counted and used to calculate total viable rates. Day 8 (post-IVF) embryos were fixed in cold methanol, washed in PBS/0.1%Tween 20, mounted in 10 μg mL–1 Hoechst 33342/glycerol and viewed under UV light to count nuclei. Percentage data were transformed using arcsine square root function before analysis, and means were compared using a one-way ANOVA and Tukey’s HSD. Although viability decreased with increasing time in straw incubation, there were no statistical differences between control, 6 and 12 h treatments for total viable rates (90.8, 80.3, and 70.8%, respectively). Average embryo stage on Day 8 for control, 6 and 12 h (7.0 ± 0.66, 6.6 ± 0.24, and 6.2 ± 0.30 s.e.m., respectively) was not different, but tended to be higher in control (P = 0.08). The change in stage, however, was different between control and 12 h (1.46 ± 0.33 and 0.66 ± 0.24, respectively; P < 0.05). Likewise, cell numbers were greater in control and 6 h embryos compared with 12 h straw incubation (149.8 ± 9.14, 138.7 ± 7.94, and 101.8 ± 5.29; n = 47, 50, and 46, respectively P < 0.01). In conclusion, 6.5 day IVP embryos held in warm Vigro holding medium for 12 h in 1/4 cc straws fail to develop at the same rate and incurred lower cell counts than either control or 6 h treatments. Further research to evaluate pregnancy rates following transfer and utilising different incubation or media and/or temperature is warranted to further evaluate the utility of in straw incubation for extended periods of time.

scholarly journals Beneficial Effects of Neurotrophin-4 Supplementation During in vitro Maturation of Porcine Cumulus-Oocyte Complexes and Subsequent Embryonic Development After Parthenogenetic Activation

2021 ◽  
Vol 8 ◽  
Author(s):  
Mirae Kim ◽  
Seon-Ung Hwang ◽  
Junchul David Yoon ◽  
Joohyeong Lee ◽  
Eunhye Kim ◽  
...  
Keyword(s):  
Treatment Group ◽  
Signaling Pathway ◽  
Oocyte Maturation ◽  
Follicular Development ◽  
Developmental Competence ◽  
Treatment Groups ◽  
Beneficial Effects ◽  
Significant Difference ◽  
Egf Signaling

Neurotrophin-4 (NT-4) is a neurotrophic factor that plays an important role in follicular development and oocyte maturation. However, it is not yet known whether NT-4 is related to oocyte maturation and follicular development in pigs. This study aims to investigate the effects of NT-4 supplementation during in vitro maturation (IVM) of porcine oocytes and subsequent embryonic development after parthenogenetic activation (PA). First, NT-4 and its receptors (TrkB and p75NTR) were identified through fluorescent immunohistochemistry in porcine ovaries. NT-4 was mainly expressed in theca and granulosa cells; phospho-TrkB and total TrkB were expressed in theca cells, granulosa cells, and oocytes; p75NTR was expressed in all follicular cells. During IVM, the defined maturation medium was supplemented with various concentrations of NT-4 (0, 1, 10, and 100 ng/mL). After IVM, the nuclear maturation rate was significantly higher in the 10 and 100 ng/mL NT-4 treated groups than in the control. There was no significant difference in the intracellular reactive oxygen species levels in any group after IVM, but the 1 and 10 ng/mL NT-4 treatment groups showed a significant increase in the intracellular glutathione levels compared to the control. In matured cumulus cells, the 10 ng/mL NT-4 treatment group showed significantly increased cumulus expansion-related genes and epidermal growth factor (EGF) signaling pathway-related genes. In matured oocytes, the 10 ng/mL treatment group showed significantly increased expression of cell proliferation-related genes, antioxidant-related genes, and EGF signaling pathway-related genes. We also investigated the subsequent embryonic developmental competence of PA embryos. After PA, the cleavage rates significantly increased in the 10 and 100 ng/mL NT-4 treatment groups. Although there was no significant difference in the total cell number of blastocysts, only the 10 ng/mL NT-4 treatment group showed a higher blastocyst formation rate than the control group. Our findings suggest that supplementation with the 10 ng/mL NT-4 can enhance porcine oocyte maturation by interacting with the EGF receptor signaling pathway. In addition, we demonstrated for the first time that NT-4 is not only required for porcine follicular development, but also has beneficial effects on oocyte maturation and developmental competence of PA embryos.

Production of in vitro bovine embryos supplemented with l-carnitine in different oxygen tensions and the relation to nitric oxide

Zygote ◽  
2020 ◽  
Vol 28 (5) ◽  
pp. 403-408
Author(s):  
Daniela Moraes Pereira ◽  
Christopher Junior Tavares Cardoso ◽  
Wilian Aparecido Leite da Silva ◽  
Mirela Brochado Souza-Cáceres ◽  
Mariana Santos ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Embryo Development ◽  
Calf Serum ◽  
Hatching Rate ◽  
Bovine Embryos ◽  
Low Oxygen ◽  
Cleavage Rate ◽  
Treatment Groups ◽  
Oxygen Tensions

SummaryThe aim of this study was to evaluate the production of bovine embryos in vitro when supplemented with l-carnitine for 24 h beginning on day 5 (d 5) under two different oxygen tensions (20% or 5%) and the relationship of nitric oxide (NO) in in vitro culture (IVC) medium to embryo development. Cumulus–oocyte complexes (COC; n = 837) were matured in vitro for 24 h and fertilization was performed for 18 h. Zygotes were cultured in vitro for 9 days after in vitro fertilization in synthetic oviductal fluid (SOF) medium with 5% fetal calf serum. At d 5 the plates were assigned to one of four treatment groups: high (20%) or low (5%) O2 tension either with or without the addition of 3.03 mM l-carnitine (High-Cont, High-Lcar, Low-Cont, Low-Lcar). The concentration of NO in the culture medium was evaluated on d 5, d 6 and d 9. On d 7, parts of the embryos were submitted for evaluation of intracellular lipid droplets. The cleavage rate was similar (P > 0.05) between high and low O2 tension and the blastocyst rate was similar in all conditions evaluated. The hatching rate was higher (P < 0.05) for Low-Cont. The NO concentration was higher at d 9 under low O2 tension (P < 0.1). The addition of 3.03 mM l-carnitine between d 5 and d 6 of IVC was not efficient in reducing cytoplasmic lipid content of bovine embryos. Additionally, IVC at a low oxygen tension without l-carnitine promoted better conditions for embryo development. A higher concentration of NO in medium was observed under low O2 tension.

148 EFFECT OF FOLLISTATIN TREATMENT POST-FERTILIZATION ON TIME TO FIRST CLEAVAGE, DEVELOPMENT TO THE BLASTOCYST STAGE, AND CELL ALLOCATION OF IN VITRO-PRODUCED BOVINE EMBRYOS

2007 ◽  
Vol 19 (1) ◽  
pp. 191
Author(s):  
K. B. Lee ◽  
A. Bettegowda ◽  
J. J. Ireland ◽  
G. W. Smith
Keyword(s):  
Blastocyst Stage ◽  
Total Cell ◽  
Mrna Abundance ◽  
Differential Staining ◽  
Bovine Embryo ◽  
Bovine Embryos ◽  
Cell Stage ◽  
Oocyte Competence ◽  
Trophectoderm Cells

Previous studies from our laboratory have demonstrated a positive association of follistatin mRNA abundance with oocyte competence. Follistatin mRNA is greater in germinal vesicle stage oocytes collected from prepubertal (model of poor oocyte competence) vs. adult animals. Furthermore, follistatin mRNA abundance is also greater in early-cleaving 2-cell bovine embryos (collected prior to the maternal zygotic transition and initiation of significant transcription from the embryonic genome) than their late-cleaving counterparts. Given these results and the fact that early-cleaving embryos develop to the blastocyst stage at a greater rate, we hypothesized that follistatin has a stimulatory role in early embryonic development. To begin to test this hypothesis, we determined the effects of follistatin treatment of in vitro-produced bovine embryos (during the initial 72 h post-fertilization) on time to first cleavage, development to the blastocyst stage (Day 7), and blastocyst cell allocation (quality). Cumulus–oocyte complexes (COCs) were harvested from ovaries obtained from a local abattoir, matured, and fertilized in vitro. After 20 h of co-incubation with spermatozoa, presumptive zygotes were stripped of cumulus cells and cultured in KSOM medium supplemented with 0.3% BSA containing 0, 1, 10, or 100 ng mL-1 follistatin (n = 25 presumptive zygotes per treatment; n = 6 replicates). Proportions of embryos reaching the 2-cell stage within 30 h (early-cleaving), 30–36 h (late-cleaving), and within 48 h post-fertilization (total cleavage rate) were recorded. Embryos at the 8–16-cell stage were separated 72 h after fertilization and cultured in fresh KSOM medium supplemented with 0.3% BSA and 10% FBS until Day 7. The proportion of embryos reaching the blastocyst stage at Day 7 post-fertilization was recorded and the numbers of inner cell mass (ICM) and trophectoderm (TE) cells determined by differential staining. Follistatin treatment did not increase the rate of total cleavage and the proportion of late-cleaving embryos when compared to control. However, supplementation with 1 and 10, but not 100, ng mL-1 follistatin increased the proportion of early-cleaving embryos (26.3 and 35.3% vs. 9.5%) and development to the blastocyst stage (28.6 and 31.7% vs. 18.4%) relative to controls (P &lt; 0.05). Treatment with 10 ng mL-1 follistatin increased total cell numbers (130.1 vs. 110.9) and proportion of trophectoderm cells (61.6% vs. 48.4%) and decreased the ICM/total cell ratio (38.4% vs. 51.5%) in Day 7 blastocysts relative to controls (P &lt; 0.05). The results indicate that exogenous follistatin treatment during the early stages of in vitro bovine embryo development can enhance time to first cleavage, development to the blastocyst stage, and cell allocation in favor of increased trophectoderm cells, and can support a potential functional role for follistatin in early embryogenesis.

81 HIGH THROUGHPUT VITRIFICATION OF IN VIVO FERTILIZED AND IN VITRO CULTURED PORCINE EMBRYOS

2011 ◽  
Vol 23 (1) ◽  
pp. 146
Author(s):  
C. N. Murphy ◽  
L. D. Spate ◽  
B. K. Bauer ◽  
R. S. Prather
Keyword(s):  
Ethylene Glycol ◽  
Uv Light ◽  
Cell Number ◽  
Total Cell ◽  
Swine Industry ◽  
Total Cell Number ◽  
Cell Stage ◽  
High Osmolarity

One barrier to successfully making embryo transfer viable in the swine industry is an inability to consistently cryopreserve oocytes and embryos. This process is made difficult by the high lipid content of porcine oocytes and embryos. The objective of this study was to test the in vivo fertilized embryo’s sensitivity to vitrification. Gilts were inseminated on the first day of standing oestrus (Day 0) and then again 12 h later. On Day 2 the oviducts and tip of the uterine horns were flushed with PVA-treated TL-HEPES and 2-cell stage embryos were collected and placed into PVA-treated TL-HEPES and centrifuged at 17 000 × g. The treatment groups were 1) 300 mOsmo centrifuged for 6 min, 2) 500 mOsmo centrifuged for 6 min, 3) 500 mOsmo centrifuged for 12 min, and 4) 500 mOsmo centrifuged for 18 min. After centrifugation the embryos were transferred to Porcine Zygote Medium 3 (PZM3) and cultured to Day 6 or 7 at which point blastocysts were vitrified using 10% DMSO, 10% ethylene glycol in M199 supplemented with 20% FBS (holding medium) for 2 min. Embryos were transferred to holding media with 20% DMSO and 20% ethylene glycol and drawn into an open pulled straw via capillary reaction; it was then submerged into LN2. Embryos were thawed using a step down concentration of 0.33 mM and then 0.2 mM sucrose in holding media each for 6–7 min and then were moved to holding medium alone for 6 to 7 min. The embryos were washed in PZM3, then transferred to 500 μL of PZM3 and cultured for 18 h. Re-expanded embryos were observed, and the nuclei of all embryos were stained with Biz-benzimide and visualised with UV light to determine total cell number. After the embryos were centrifuged and cultured, there was no difference in development to blastocyst (SAS Institute, Cary, NC, USA; Proc GLM) with a mean percentage blastocyst of 85.1% and an N of 54, 51, 53, and 51, respectively, for each treatment. After thawing, percentage of embryos re-expanded was 23.5a, 26.4a,b, 43.2a,b, and 45.6b, respectively. Data was analysed using a PROC GLM in SAS (P < 0.05), with 37, 43, 30, and 36 embryos in each group, respectively. No difference in total cell number across treatments was detected after analysis using PROC GLM in SAS (P < 0.05) with a mean cell number of 29.0. These data suggest that in vivo matured and fertilized blastocysts can survive high osmolarity treatment, centrifugation, and vitrification. The data also show that a high osmolarity treatment centrifuged for 18 min leads to a greater number of re-expanded embryos post-thaw, which may be attributed to better separation of the lipid. Funded by the NIH NCRR R21RR025879 and Food for the 21st Century.

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