Effect of culture conditions on artificial activation of porcine oocytes matured in vitro

1996 ◽  
Vol 8 (8) ◽  
pp. 1153 ◽  
Author(s):  
N Yamauchi ◽  
H Sasada ◽  
S Sugawara ◽  
T Nagai
Keyword(s):  
In Vitro Maturation ◽  
Fetal Calf Serum ◽  
Culture Media ◽  
Calf Serum ◽  
Treated Group ◽  
Culture Conditions ◽  
Culture Period ◽  
Subsequent Response ◽  
Artificial Activation

The effects of culture media used and culture period for in vitro maturation of porcine oocytes on their subsequent response to chemical and electrical activation, were investigated. Activated oocytes were identified by the presence of a pronucleus(ei) or cleavage. Porcine oocytes were cultured for 24, 30, 36, 42 and 48 h in TCM199 with Earle's salts (199) supplemented with 10% fetal calf serum (199-FCS) before electrical stimulation. Although few oocytes were activated after 24 h and 30 h of culture (5.4% and 6.1% respectively), the percentage of activated oocytes increased significantly to 93.2% after 42 h in culture (P < 0.05); however, when the culture period was extended to 48 h, there was a significant decrease to 56.7% (P < 0.05). Oocytes were also cultured in four types of media: (1) 199-FCS; (2) 199 supplemented with 5 mg mL-1 bovine serum albumin (199-BSA); (3) Kreb's-Ringer bicarbonate solution supplemented with 10% FCS (KRB-FCS); and (4) KRB supplemented with BSA (KRB-BSA). After 42 h of culture in each medium, the oocytes were electrically activated. Although rates of maturation of oocytes cultured in the four media were similar (74.0-80.8%), all oocytes except those cultured in 199-FCS failed to be activated. In addition, oocytes were cultured for 36, 42 and 48 h in 199-FCS and then stimulated by treatment with ethanol. Significantly fewer oocytes were activated in the chemically-treated group than in the electrically-treated group. These results indicate that culture conditions used for the culture of porcine oocytes in vitro are important with respect to their subsequent response to artificial activation.

326 EVALUATION OF CULTURE DURATION AND PARTIAL CUMULUS CELL REMOVAL DURING CANINE OOCYTE MATURATION

2006 ◽  
Vol 18 (2) ◽  
pp. 270
Author(s):  
C. Hanna ◽  
C. Long ◽  
M. Westhusin ◽  
D. Kraemer
Keyword(s):  
In Vitro Maturation ◽  
Calf Serum ◽  
Cumulus Cell ◽  
Germinal Vesicle ◽  
Cumulus Cells ◽  
Culture Conditions ◽  
Germinal Vesicle Breakdown ◽  
Significant Difference ◽  
Culture Duration

The objectives of this study were to determine whether the percentage of canine oocytes that resume meiosis during in vitro maturation could be increased by either increasing culture duration or by removing approximately one-half of the cumulus cells 24 h after oocytes were placed into culture. Canine female reproductive tracts were collected from a local clinic and ovaries were minced in warm TL-HEPES. Oocytes with a consistently dark ooplasm and at least two layers of cumulus cells were selected, cultured in a basic canine oocyte in vitro maturation medium consisting of TCM-199 with Earl's salts, 2.92 mM Ca-lactate, 20 mM pyruvic acid, 4.43 mM HEPES, 10% fetal calf serum, 1% Penicillin/Streptomycin (GibcoBRL, Grand Island, NY, USA), and 5 μg/mL porcine somatotropin, and incubated at 38.5°C in 5% CO2 in humidified air. Treatment groups were randomly assigned and oocytes were cultured for 60, 84, or 132 h (Basic). From each of these groups, one-half of the oocytes were pipetted through a fine bore pipette to partially remove the cumulus cells 24 h after the start of culture (Basic–1/2). At the end of culture, all oocytes were denuded and the nuclear status was observed with Hoechst 33342 under ultraviolet fluorescence. All data were analyzed by ANOVA with P < 0.05. Since the canine oocyte is ovulated at the germinal vesicle (GV) stage of meiosis and requires up to five days to mature in the oviduct, it was hypothesized that an increased culture time would allow for more oocytes to undergo nuclear maturation to metaphase II (MII). It was also hypothesized that partial removal of cumulus cells would decrease the cumulus cell component in the ooplasm that sustains meiotic arrest, allowing for more oocytes to resume meiosis (RM = germinal vesicle breakdown to MII). Results within each treatment group indicate that there is no significant difference between culture duration and the percent of oocytes that mature to MII. Additionally, there was no significance in the percent of oocytes that resumed meiosis after partial cumulus cell removal. Taken together, these data suggest that neither treatment is effective in canine in vitro maturation systems, given the current maturation culture conditions. Table 1. Nuclear status* of oocytes for three time periods with or without partial cumulus cell removal

74 EFFECT OF SIZE AND CULTURE PERIOD OF FROZEN–THAWED BOVINE TROPHOBLASTIC VESICLES ON INTERFERON-τ SECRETION

2014 ◽  
Vol 26 (1) ◽  
pp. 151
Author(s):  
Y. Hashiyada ◽  
H. Takahashi ◽  
D. Yamaguchi ◽  
K. Imai ◽  
M. Geshi
Keyword(s):  
Significant Positive Correlation ◽  
Culture Media ◽  
Fetal Bovine Serum ◽  
Calf Serum ◽  
Culture Period ◽  
Fetal Bovine ◽  
Student’S T ◽  
Student’S T Test

Frozen–thawed bovine trophoblastic vesicles (bTV) derived in vivo could secrete interferon-τ (IFN-τ) at the same level as fresh bTV on Days 4 to 6 after thawing. However, amounts of IFN-τ decreased following continuous in vitro culture (Hashiyada et al. 2012 38th IETS). Co-transfer of frozen–thawed bTV improved pregnancy rate of embryos due to the effects of IFN-τ secreted by bTV (Hashiyada et al. 2008 41th SSR). However, the relation between bTV size and IFN-τ secretion level during culture has not been well documented. The objective of present study was to characterise the concentration of IFN-τ related bTV volume and culture period after thawing of cryopreserved bTV. The bTV were prepared from Day 16 elongating blastocysts recovered nonsurgically. The dissected trophoblastic fragment, 1 to 1.5 mm in width, was cultured using TCM-199 supplemented with 20% (vol/vol) fetal bovine serum and 0.1 mM β-mercaptoethanol. Formed vesicles after 24 h of culture were cryopreserved using D-PBS supplemented with 20% calf serum and 1.8 M ethylene glycol. After thawing, bTV were cultured individually with 100 μL/well/day until Day 2 (i.e. the day of thawing was defined as Day 0), and thereafter changed to 200 μL/well/day to termination at Day 10. Collection of culture media and measurement of bTV diameter were performed before cryopreservation and after thawing for every day. Interferon-τ in collected media was measured by radioimmunoassay. The estimated bTV volume was calculated based on the diameter. Data were analysed by Student's t-test. Nine fresh bTV before cryopreservation were used to assess the IFN-τ secretion for 24 h in relation to bTV volume. A significant positive correlation was observed between secreted IFN-τ (mean ± s.e.M, 19.9 ± 3.1 ng mL–1) and bTV volume (1.49 ± 0.6 mm3, r = 0.91; P < 0.01). Initial IFN-τ secretion from bTV cultured for 24 h after thawing was significantly decreased compared with that before cryopreservation (29.1 ± 2.1 ng mL–1 and 58.4 ± 4.8 ng mL–1; P < 0.01, n = 27). In continuous culture of bTV (n = 8), IFN-τ secretion increased gradually from Day 2 (23.1 ± 9.0 ng mL–1) to Day 4 (32.2 ± 8.4 ng mL–1), and then maintained this level until Day 7 (33.4 ± 14.9 ng mL–1). However, this amount of IFN-τ tended to decrease on Day 8 (24.8 ± 5.0 ng mL–1), 9 (16.5 ± 4.4 ng mL–1), and 10 (12.0 ± 1.7 ng mL–1). Interferon-τ secretion from bTV on Day 9 and 10 was lower than that on Day 3, 4, 5, 6, and 8, respectively (P < 0.05). Volume of bTV increased also from Day 2 (0.2 ± 0.1 mm3) to Day 5, 6 (0.8 ± 0.3 mm3) and 7 (0.7 ± 0.2 mm3). However, bTV volumes shrank drastically on Day 8 (0.3 ± 0.1 mm3), 9, and 10 (0.2 ± 0.1 mm3). In comparison with bTV during culture, volumes on Day 4, 5, and 7 were greater than those on Day 2 and 3, and volumes on Day 6 and 7 were greater than on Day 8, 9, and 10 (P < 0.05). These results indicate that the dynamics of IFN-τ secretion reflected the expansion or reduction of bTV in continued culture after thawing. Interferon-τ secretion might be related to bTV volume. Moreover, we reconfirmed that cryopreserved bTV highly express IFN-τ during 4 to 7 days after thawing.

A staging scheme for assessing development in vitro of organogenesis stage embryos of the stripe-faced dunnart, Sminthopsis macroura (Marsupialia: dasyuridae)

Reproduction ◽  
2000 ◽  
pp. 99-108 ◽  
Author(s):  
YP Cruz ◽  
D Hickford ◽  
L Selwood
Keyword(s):  
Fetal Calf Serum ◽  
Calf Serum ◽  
Microscopic Analysis ◽  
Culture Conditions ◽  
Didelphis Virginiana ◽  
Morphological Development ◽  
Rat Serum ◽  
Sminthopsis Macroura ◽  
Development In Vitro

The inaccessibility of mammalian organogenesis stage embryos has precluded their widespread use in embryological and teratological studies. As organogenesis occurs during the last 1.5 days of the 10. 7 days of gestation in the stripe-faced dunnart (Sminthopsis macroura), the aim of the present study was to investigate whether day 9 and day 10 embryos and fetuses could be grown to term in vitro. High glucose Dulbecco's modified Eagle's medium with 10% fetal calf serum (FCS) supported embryonic growth for various periods of time, some to within 5 h of the predicted time of parturition. A roller culture system maintained at 35 degrees C was used to incubate organogenesis stage embryos (n = 43). Nine unincubated (control) embryos were either fixed for microscopic analysis or frozen for microprotein determination. The results of the present study indicate that with some optimization of the culture conditions (increasing oxygen in the gas phase in the culture tubes, replacing FCS with rat serum), it might be possible for organogenesis stage S. macroura embryos to be grown to term. A scoring scheme for assessing morphological development was devised for use as a standard in staging organogenesis stage embryos. This scheme reflects the highly compressed schedule of developmental events that occurs mainly during day 9 of gestation in S. macroura embryos. In comparison, during embryogenesis in Didelphis virginiana these developmental events occur from day 8 to day 10.5 of gestation, and birth occurs on day 13.

scholarly journals 318EFFECT OF PIG FOLLICLE FLUID AND FETAL CALF SERUM ON PORCINE OOCYTE MATURATION AND SUBSEQUENT DEVELOPMENT AFTER ACTIVATION AND SOMATIC CELL NUCLEAR TRANSFER

2004 ◽  
Vol 16 (2) ◽  
pp. 278
Author(s):  
Z. Liu ◽  
L. Lai ◽  
G. Im ◽  
M. Samuel ◽  
D. Wax ◽  
...  
Keyword(s):  
Somatic Cell Nuclear Transfer ◽  
Nuclear Transfer ◽  
In Vitro Maturation ◽  
Fetal Calf Serum ◽  
Calf Serum ◽  
Defined Medium ◽  
Chemically Defined Medium ◽  
Maturation Rate ◽  
Blastocyst Rate

In vitro maturation of porcine oocytes is very important for understanding porcine somatic cell nuclear transfer (SCNT). In order to develop an in vitro maturation system that can provide more high quality oocytes, the effect of porcine follicle fluid (pFF) (gathered from 3–5-mm porcine follicles) and fetal calf serum (FCS: Sigma, St. Louis, MO, USA), as an important additional component of a chemically-defined medium was studied. Cumulus-oocyte complexes (COC) derived from follicles 3–5mm in diameter were cultured in three different media: a chemically-defined medium (CDM: TCM-199 with 0.1mgmL−1 cysteine, 10ngmL−1 EGF, 0.5μgmL−1 LH and 0.5μgmL−1 FSH); CDM with 10% pFF (CDM+p); and CDM with 10% FCS (CDM+F). After 42–44h of maturation, oocytes with a clear polar body were classified as matured oocytes. Matured oocytes stimulated by electric pulse (120v, 30μs, 2 pulse), or enucleated and fused with fibroblasts to construct SCNT embryos by using the same electrical parameters. All of these parthenogenetic and SCNT embryos were cultured in Porcine Zygote Medium-3. The blastocyst rate was assessed under a stereomicroscope on Day 6, and the number of nuclei in the blastocysts was counted under a fluorescent microscope after staining with 5μgmL−1 of Hoechst 33342. All data were subjected to a Generalized Linear Model Procedure (PROC-GLM) of Statistical Analysis System (SAS). The maturation rates of porcine oocytes in CDM and CDM+p were 53.2±3.8% (539/1050) and 69.7±3.8% (587/847), respectively;; in CDM and CDM+F, 61.1±3.1% (471/776) and 70.2±3.7% (577/844), respectively. Oocytes matured in CDM+p and CDM+F showed a higher (P&lt;0.05) maturation rate than those in CDM. The percentages of parthenogenetic blastocysts of oocytes matured in CDM and CDM+p were 13.9±2.1% (35/250) and 20.2±5.3% (64/300), and the numbers of nuclei in these blastocysts were 25.8±2.3 and 25.8±1.4, respectively. The blastocyst rate from CDM- and CDM+F-matured oocytes were 20.1±2.0% (53/272) and 22.2±4.7%(71/298), and the numbers of nuclei in these blastocysts were 24.7±1.5 and 25.3±1.5, respectively. There were no significant (P&gt;0.05) differences in the percentages of parthenogenetic blastocysts and nuclei numbers between CDM and CDM+p, or CDM and CDM+F. The percentages of blastocysts in SCNT embryos derived from CDM and CDM+p were 8.1±1.5% (14/192) and 12.3±1.9% (24/192), while the nuclei numbers in these blastocysts were 26.6±1.2 and 34.5±2.2, respectively. The percentages of blastocysts after SCNT from oocytes matured in CDM and CDM+F were 24.3±4.9% (35/139) and 27.1±5.5% (45/176), while the numbers of nuclei were 29.8±2.5 and 32.2±1.9, respectively. There were no significant (P&gt;0.05) differences between CDM and CDM+p, or CDM and CDM+F in SCNT embryo blastocyst rate, but the SCNT embryos derived from CDM+p showed a higher (P&lt;0.05) nuclear number. In conclusion, these results indicate that 10% pFF or FCS in CDM can promote a higher maturation rate of porcine oocytes. As recipient cytoplasm for SCNT, oocytes matured in CDM+p can support development of blastocysts that contain more nuclei than those matured in CDM alone. Supported in part by Food for the 21st Century and RR13438.

89 PHENAZINE ETHOSULFATE AND FETAL CALF SERUM EFFECT IN THE ULTRASTRUCTURE AND DEVELOPMENT OF IN VITRO-PRODUCED BOVINE EMBRYOS

2012 ◽  
Vol 24 (1) ◽  
pp. 157 ◽  
Author(s):  
M. J. Sudano ◽  
D. M. Paschoal ◽  
T. S. Rascado ◽  
L. F. Crocomo ◽  
M. D. Guastali ◽  
...  
Keyword(s):  
Lipid Content ◽  
Lipid Droplets ◽  
Fetal Calf Serum ◽  
Culture Media ◽  
Calf Serum ◽  
Bovine Embryos ◽  
Culture Methods ◽  
Mitochondrial Number ◽  
Phenazine Ethosulfate

Over the past decades, there have been great advances in in vitro production (IVP) systems, with improved culture methods and new knowledge regarding embryo physiology, ultrastructure and morphology. Currently, the major obstacle associated with the extensive use of this technology is the great sensitivity of IVP embryos to cryopreservation. According to the literature, the reduced cryotolerance of IVP embryos is frequently associated with their high lipid content. Although is not clear until now how the lipid accumulation occurs, it may be influenced by the use of undefined culture media, supplemented with fetal calf serum (FCS); or as a result of embryo energy metabolism abnormalities that affect mitochondrial function, leading to the decrease in both the embryo quality and survival after cryopreservation. In this context, phenazine ethosulfate (PES), a reducer of NADPH electrons, which favours pentose–phosphate pathways and also inhibits the fatty acids synthesis, has been used to increase IVP embryo cryotolerance (Sudano et al. 2011 Theriogenology 75, 1211–1220). The aim of the present study was to evaluate the phenazine ethosulfate and FCS effect in the ultrastructure of IVP bovine embryos. A 2 × 2 factorial experiment design was used to test 2 FCS concentrations (0 or 10%) and the addition of PES (without or with PES) in the culture media. Slaughterhouse ovaries were used to obtain oocytes which were matured and fertilized in vitro (Day 0). Presumptive zygotes (n = 1440) were divided in 4 culture media: SOFaa without FCS; SOFaa without FCS + 0.3 μM PES (started on Day 4); SOFaa + 10% FCS; SOFaa + 10% FCS + 0.3 μM PES (started on Day 4). Embryo development was evaluated after 7 days under standard culture conditions (at 38.5°C in atmosphere of 5% O2, 5% CO2 and 90% N2). Transmission electron microscopy (TEM) was performed on Day-7 blastocysts from each group (n = 5) through standard protocol. For the statistical analysis, the arcsine transformation was applied to blastocyst percentage data and submitted to the ANOVA, followed by Tukeys' test through PROC GLM (SAS Institute Inc., Cary, NC, USA). In the absence of significant interactions, only main effect means are presented. The blastocyst production was not affected (P = 0.47) by the use of PES (42.7 ± 3.2 vs 39.3 ± 3.2, respectively for control and PES Day 4). The addition of 10% of FCS increased (P < 0.0001) the percentage of blastocysts (48.9 ± 3.2 vs 33.0 ± 3.2, respectively, for 10% and 0% of FCS). The ultrastructure analysis showed similar features in embryos from all studied groups. However, embryos cultured in the absence of FCS presented fewer and smaller lipid droplets. Moreover, embryos cultured without FCS presented more cellular debris in the perivitelinic space and in the blastocoele, indicating loss of blastomeres. The use of PES was able to reduce lipid droplets and increase the mitochondrial number in serum-produced embryos. Therefore, the PES decreased lipid content and increased mitochondrial number without affecting the development and ultrastructure of IVP bovine embryos. FAPESP 09/54513-3, 10/09922-0.

Embryonic development in culture of the marsupials Antechinus stuartii (Macleay) and Sminthopsis macroura (Spencer) during preimplantation stages

1993 ◽  
Vol 5 (4) ◽  
pp. 445 ◽  
Author(s):  
A Yousef ◽  
L Selwood
Keyword(s):  
Culture System ◽  
Fetal Calf Serum ◽  
Normal Development ◽  
Culture Media ◽  
Calf Serum ◽  
Human Amniotic Fluid ◽  
Antechinus Stuartii ◽  
Sminthopsis Macroura

Forty-nine blastocysts from 11 brown antechinus, Antechinus stuartii, and 96 blastocysts from 17 stripe-faced dunnarts, Sminthopsis macroura, were used to develop a culture system for embryos during preimplantation stages. Blastocysts of brown antechinus were collected on Days 6-9 for unilaminar stages, Days 16-21 for bilaminar stages and Days 20 and 21 for trilaminar stages. Blastocysts of stripe-faced dunnarts were collected on Day 6 for unilaminar stages, Days 6-8 for bilaminar stages and Day 8 for trilaminar stages. Culture media were Dulbecco's modified Eagle's medium (DMEM) with 4.5% glucose and Whittingham's T6 medium both of which were supplemented with 5, 10, 12.5 and 20% fetal calf serum (FCS). Antechinus serum (5%) and bovine serum albumin (0.1%, 0.2%) were also added to some media. Human amniotic fluid (HAF) and Monomed media were also tested. Blastocysts were cultured at 35 degrees C in 5% CO2 in air. DMEM + 10% FCS and HAF supported normal development for the longest periods and over the greatest range of stages. Developmental failure of blastocysts in vitro during expansion of the unilaminar blastocyst and formation of the bilaminar blastocyst suggests that these stages may be dependent on uterine signals. When cultured in DMEM + 10% FCS, the rate of development of bilaminar and trilaminar blastocysts into organogenesis was 4 h slower than in vivo in the stripe-faced dunnart and about 6 h slower than in vivo in the brown antechinus. Embryos of stripe-faced dunnarts were cultured to within 18 h of birth.

scholarly journals Meiotic Status Does Not Affect the Vitrification Effectiveness of Domestic Cat Oocytes

Animals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1371
Author(s):  
Natalia Sowińska ◽  
Jennifer Zahmel ◽  
Wojciech Niżański ◽  
Romy Hribal ◽  
Lorena Fernandez-Gonzalez ◽  
...  
Keyword(s):  
In Vitro Maturation ◽  
Fetal Calf Serum ◽  
Calf Serum ◽  
Toxicity Assessment ◽  
Domestic Cat ◽  
Developmental Potential ◽  
Vitro Fertilization ◽  
Negative Effect ◽  
Meiotic Competence

Cryopreservation is important for animal fertility and biodiversity. Unfortunately, cryopreservation of feline oocytes is still an experimental technique. The aims of this study were to analyze the potential toxicity of the cryoprotectants in the vitrification solution (VS) on cat oocytes and to investigate whether the meiotic status of oocytes influences their developmental potential after vitrification. Two experiments were conducted with the VS composed of 20% ethylene glycol, 20% dimethyl sulfoxide, 20% fetal calf serum, 1.5 M trehalose, and 10% Ficoll PM-70: (1) toxicity assessment of the VS on immature cumulus oocyte complexes (COCs), and subsequently in vitro maturation (IVM) and in vitro fertilization; (2) assessment of the influence of the meiotic status on vitrification effectiveness, where immature and in vitro matured COCs were vitrified on the Cryotop. After rewarming, vitrified oocytes were subjected to IVM (immature) and intracytoplasmic sperm injection (ICSI) with fresh epididymal sperm. The toxicity test revealed no negative effect of oocyte exposure to the applied VS on their developmental potential (p > 0.05). Although the vitrification procedure itself significantly reduced the meiotic competence of oocytes, their meiotic status before vitrification (immature vs. in vitro matured) did not influence fertilization and morula rates. The only parameter affected by vitrification was the rate of oocytes suitable for ICSI, which was significantly lower for immature oocytes. Regardless of the meiotic status of vitrified oocytes, morphologically normal morulae were obtained. Moreover, the two meiotic stages examined are suitable for vitrification, with mature oocytes being a better choice when a well-equipped laboratory is available.

scholarly journals The effects of Glucose and Ascorbic acid on in vitro development of Echinococcus granulosus Metacestodes

2021 ◽  
Author(s):  
Seyede Sogand Sajadi ◽  
Ali Haniloo ◽  
Samad Nadri ◽  
Negin Torabi
Keyword(s):  
Ascorbic Acid ◽  
Culture Medium ◽  
Fetal Calf Serum ◽  
Culture Media ◽  
Calf Serum ◽  
Infected Sheep ◽  
Control Group ◽  
Antioxidant Vitamin ◽  
Vitro Development

Abstract Echinococcus granulosus-developed metacestodes in the cultured medium are used for the assessment of its susceptibility to different compounds; however, this procedure is time-consuming and risky. In the present study, aspirated protoscoleces from the infected sheep were used to evaluate the effects of glucose, as an energy source, as well as ascorbic acid, as an antioxidant vitamin, on larval development. Protoscoleces were maintained in RPMI1640 culture media containing 10% fetal calf serum, as well as different concentrations of glucose (6 and 8 mg/ml) and ascorbic acid (25, 50, and 100 µg/ml). A culture medium containing 4 mg/ml of glucose was served as the control. Larger cysts were achieved in a shorter time from the medium enriched with 6 mg/ml of glucose (740 ± 20 µm) compared to the control group (420 ± 40 µm). However, in the groups treated with ascorbic acid, the number of cysts was higher in 100 µg/ml (32.5 ± 0.7) compared to the control group (12.5 ± 0.7). Additionally, the mature cysts were achieved on the 7th day of cultivation with 100 µg/ml of ascorbic acid compared to 18 days in the control group.

Influence of day-0 and day-7 superovulated cow serum during development of bovine oocytes in vitro

1994 ◽  
Vol 6 (2) ◽  
pp. 261 ◽  
Author(s):  
A Boediono ◽  
M Takagi ◽  
S Saha ◽  
T Suzuki
Keyword(s):  
Culture Medium ◽  
Fetal Calf Serum ◽  
Culture Media ◽  
Calf Serum ◽  
Blastocyst Development ◽  
Cleavage Rate ◽  
Low Concentrations ◽  
Maturation Medium ◽  
Bovine Oocytes

Oocytes were matured in medium supplemented with 5% serum collected from superovulated cows at oestrus (Day-0 SCS) or at the time of embryo collection (Day-7 SCS), or in medium supplemented with fetal calf serum (FCS). After insemination using frozen-thawed sperm, oocytes were cultured in vitro with medium supplemented with 5% Day-0 SCS or 5% Day-7 SCS or 5% FCS. The proportions of embryos that cleaved were not significantly different among treatments, whereas development of the embryo to a blastocyst was significantly higher in the presence of SCS than FCS. When the four possible combinations of Day-0 SCS and Day-7 SCS were used in the maturation and culture media, there were no differences among treatments, except that the cleavage rate was significantly higher (P < 0.05) with Day-0 SCS in the maturation medium and Day-7 SCS in the culture medium than with Day-7 SCS in the maturation medium and Day-0 SCS in the culture medium. The proportions of embryos that cleaved and developed to blastocysts were not related with the level of progesterone and luteinizing hormone in the serum added to the maturation and culture media. However, the use of serum with low concentrations of glucose, fatty acids and cholesterol in the maturation medium and the culture medium tended to be associated with a higher rate of cleavage and blastocyst development.

Sign in / Sign up

Export Citation Format

Share Document