• Reproductive and Developmental Biology
• /
• v.37 no.4
• /
• pp.281-287
• /
• 2013

In mammal, unfertilized oocytes remain in the oviduct or under in vitro culture, which is called "oocyte aging". This asynchrony negatively affects fertilization in pre- and post-implantation embryo development. Caffeine a phosphodiesterase inhibitor is known to rescue oocyte aging in several species. The objective of this study is to determine the cytoskeleton distribution in aged oocytes and the embryo developmental ability of aged oocytes in the present or absence of caffeine during maturation. Caffeine treatment increased the incidence of normal spindle assembly of aged oocytes (treatment, $67.57{\pm}4.11%$ aging, $44.61{\pm}6.4%$) and no significant differences compared to control group. Fluorescence values were compared using ROS (Reactive oxidation species) stain. Fluorescence values appear of control group intensity rate ($51.53.{\pm}3.80$), aging group ($68.10{\pm}5.54$) and treatment of caffeine ($45.04{\pm}2.98$). Aged oocytes that were derived from addition of caffeine to the IVM (in vitro maturation) medium had significantly increased 2-cell that developed to the blastocyst stage compared to the aging group. Blastocysts, derived from caffeine treatment group, significantly increased the total cell number compare aging ($90.44{\pm}10.18$ VS $67.88{\pm}7.72$). Apoptotic fragments of genomic DNA were measured in individual embryo using TUNEL assay. Blastocyst derived from caffeine treatment group decreased significantly the apoptotic index compared to blastocyst derived from aging group. In conclusion, we inferred that the caffeine treatment during oocyte aging can improve the developmental rate and quality in bovine embryos developing in vitro.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.12
• /
• pp.1675-1677
• /
• 2001

The effect of the presence or absence of corpus luteum in the ovaries of slaughtered buffaloes was studied for the oocytes recovery and their subsequent maturation and fertilization in vitro. On an average, 0.41 and 0.67 oocytes per ovary were recovered from ovaries with and without corpus luteum, respectively. Immature oocytes were matured in TCM-199 medium. Significant difference was observed in maturation rate between good (74%) and fair (37%) oocytes. However, there was no significant difference in cleavage rate between the two types. The results of this study show that although the presence of corpus luteum in the ovary at the time of recovery significantly affected availability of total oocytes and in-vitro maturation, but fertilization and cleavage remained unaffected under in vitro conditions.

• Korean Journal of Animal Reproduction
• /
• v.14 no.1
• /
• pp.50-56
• /
• 1990

Bovine oocytes obtained from follicles(2~5mm) of ovaries after slaughter were cultured in TCM 199 medium with 10~20% heat-inactivated estrus cow serum(ECS) for 25~27 hr, at 39$^{\circ}C$ under 5% CO2 in air. At the end of culture period, some oocytes were stained with 1% acetoorcein and examined for the evidence of oocyte maturation. The remainder were used to assess the potential of in vitro fertilization(IVF) with frozen-thawed spermatozoa and subsequent development in media with or without bovine oviduct epithelial cell (BOEC) co-culture. The results obtained were summarized as follows ; 1. The maturation rate of oocyte in vitro in TCM 199 medium with 15% ECS group(76.3) was superior to 10% ECS group(68.3%) and 20% ECS group(64.5%). 2. The IVF rates of oocytes matured in vitro, and formation rate of male and female pronuclei were 63.6%(77/121) and 93.5%(72/77), respectively. The incidence of polyspermy was very low(2.4%). 3. Of 73 oocytes fertilized in vitro and cultured in TCM 199 medium with 10% fetal calf serum for 7 days, 41(56.3%) were cleaved over 2-cell and only 1(2.4%) was developed beyond the 16-cell stage. 4. Of 76 oocytes co-cultured with BOEC, 58(76.3%) were cleavaged and 23(39.7%) were developed to morula and blastocyst stage. The results of this study indicate that co-culture with BOEC deserved a positive effect on the IVF oocyte development through the 16-cell block.

• Journal of Embryo Transfer
• /
• v.12 no.2
• /
• pp.181-188
• /
• 1997

This study was carried out to determine the effect of bovine follicular fluid(bFF), hormones, and fetal bovine serum(FBS) supplemented in the medium on the in vitro fertilization and development of bovine embryos. The ovaries were obtained from a local abattoir and placed in physiological saline kept at 30~32˚C and brought to the laboratory within 3~4 hours. The oocytes and follicular fluid were collected by aspiration from visible follicles, and the oocytes of grades I on the basis of the morphology of cumulus cells attached and the homogeneity of cytoplasmic granules were selected and used for maturation. The basal media used for oocyte maturation, fertilization and embryo development in vitro were Ham' F-10, TALP and TCM-199, respectively. The hormones supplemented in maturation medium were consisted of 35 pg /ml FSH, 10 pg /ml LH and 1 pg/mi estradiol-l7$\beta$. The bFF collected from 5~9 mm follicles was centrifuged, filtered and inactivated by heat-treatment at 56˚C for 30 min. FBS also was inactivated with the same method and kept at -20˚C until use. The embryos were co-cultured with the monolayer of bovine oviductal epithelial cells at 39˚C under 5% $CO_2$ in air for 9 days. The results obtained were summarized as follows: The fertilization rate of oocytes was found 87.4% from 10% FBS and hormones treatment for IVM, and 37.1% of these TVF embryos were developed to blastocyst stage in 10% FBS groups. Compared with this control system, the fertilization rate was decreased significantly(P<0.05) in the maturation without either FBS or hormones. These IVF embryos were developed to morula stage at the similar rate, but to blastocyst at significantly(P<0.05) lower rate in the embryo culture with or without FBS supplementation. The fertilization rate(82.9%) in hormones and 10% inactivated bFF was similar with 10% FBS and hormone groups(87.4%), but decreased significantly(P<0.05) in 20 or 30% bFF (61.0 or 66.0%), respectively. In vitro developmental competence to blastocyst stage in 10% FBS and 20% inactivated bFF(37.1% and 31.4%) was higher than in 10 or 30% inactivated bFF(20.0 or 19.2%) or 10, 20 and 30% fresh bFF(19.1, 21.0 and 17.5%) The results indicated that the in vitro fertillzation and development rate of the embryos should be improved in 10% FBS or 20% inactivated culture system and 20% inactivated bFF might be available economically for bovine oocyte maturation and embryo culture instead of fetal bovine serum.

• Korean Journal of Agricultural Science
• /
• v.35 no.2
• /
• pp.167-176
• /
• 2008

Supplementation of serum and estrogen in in vitro maturation(IVM) medium was shown to improve embryo development and quality in several species. This study investigates the effect of ovarian estrus stage on canine oocyte quality and supplementation of medium with canine serum or estrogen on IVM of canine oocytes. As results, in experimental 1, IVM oocytes collected from follicular stage ovaries to MII stages($10.2{\pm}1.5%$) was higher (p<0.05) with 10% canine estrus stage serum than control($1.3{\pm}1.6%$), anoestrus stage serum($4.0{\pm}1.6%$), luteal stage serum($2.7{\pm}1.7%$) and 10% FBS($1.3{\pm}1.6$). In experimental 2, 10% canine estrus stage serum supplementation has highest maturation rate to MII stages($10.0{\pm}1.8%$) and there were significant differences(P<0.05) with another treatment in follicular stages group. In order to investigate the synergic effect of estrous serum and estrogen supplementation, different estrous stage groups of oocytes were cultured with 2 ug/ml estrogen plus various concentrations of different reproductive stage serum and FBS(experimental 3). As results, the rate of maturation to metaphase II(MII) stage was significantly higher(p<0.05) in oocytes from the follicular stage supplemented with estrogen and 10% canine estrus stage serum(11.5%) compared to the other groups(6.0 - 8.8%). The present study was demonstrated that canine serum and the estrus cycle of the bitch affect the meiotic competence of oocytes. Hormonal influences within the follicle may be one of the factors responsible for the greater proportion of maturation of oocyte to MII from bitches at the follicular phase.

• Korean Journal of Agricultural Science
• /
• v.48 no.1
• /
• pp.163-170
• /
• 2021

Bacterial infections in the female reproductive tract negatively affect ovarian function, follicular development, and embryo development, leading to the eventual failure of fertilization. Moreover, bacterial lipopolysaccharides (LPS) can interfere with the immune system and reproductive system of the host animal. Therefore, this study examined the effect of LPS on the in vitro maturation (IVM) of pig oocytes. Oocytes were matured in TCM199 medium in the presence of varying concentrations of LPS (0 - 50 ㎍·mL^-1). The maturation rate, cortical granules (CGs) migration, and chromosome alignment were subsequently evaluated during the meiotic development of the oocytes. We observed a dose-dependent and significant decrease in the metaphase II (MII) rate with increasing concentrations of LPS (97.6% control [0 ㎍·mL^-1 LPS] vs. 10.4-74.9% LPS [1 - 50 ㎍·mL^-1], p < 0.05). In addition, compared to the control oocytes without LPS, higher levels of abnormal CGs distribution (18.1 - 50.0% LPS vs. 0% control), chromosome/spindle alignment (20.3 - 56.7% LPS vs. 0% control), and intracellular ROS generation were observed in oocytes matured with LPS (p < 0.05). Nitrite levels were also increased in the maturation medium derived from the oocytes matured with LPS (p < 0.05). These results indicate that LPS induces oxidative stress during IVM and affects oocyte maturation, including CGs migration and chromosome alignment of pig oocytes.

• Journal of Embryo Transfer
• /
• v.27 no.3
• /
• pp.163-169
• /
• 2012

The 3-isobutyl-1-methylxanthine (IBMX) is non-selective phosphodiesterase and is able to prevent resumption of meiosis by maintaining elevated cyclic AMP (cAMP) concentrations in the oocyte. The present study was conducted to analyze: (1) nuclear maturation (examined by the Hoechst staining), (2) whether cytoplasmic maturation (examined by the intracellular glutathione (GSH) concentration) of porcine oocytes is improved during meiotic arrest after prematuration (22 h) with IBMX. Before in vitro maturation (IVM), oocytes were treated with 1 mM IBMX for 22 h. After 22 h of pre-maturation, the higher rate of IBMX treated group oocytes were arrested at the germinal vesicle (GV) stage (42.3%) than control IVM oocytes (10.1%). It appears that the effect of IBMX on the resumption of meiosis has shown clearly. In the end of IVM, the reversibility of the IBMX effect on the nuclear maturation has been corroborated in this study by the high proportions of MII stage oocytes (72.5%) reached after 44 h of IVM following the 22 h of inhibition. However, intracellular GSH concentrations were lower in the oocytes treated with IBMX than the control oocytes (6.78 and 12.94 pmol/oocyte, respectively). These results demonstrate that cytoplasmic maturation in porcine oocytes pre-treated with IBMX for 22 h did not equal that of control oocytes in the current IVM system. These results indicate that pre-maturation with IBMX for 22 h may not be beneficial in porcine IVM system.

• Korean Journal of Animal Reproduction
• /
• v.21 no.4
• /
• pp.355-362
• /
• 1997

This study was undertaken in an effort to product embryos through in vitro maturation(IVM), in vitro fertilization(IVF) and in vitro culture(IVC) after cryopreservation of immature and mature porcine oocytes. The experiments were conducted to investigate IVM rate of oocytes frozen with 3 different cryoprotectants and to examine IVF and IVC of frozen-thawed oocytes. The CEI(cumulus cells expansion index) after IVM of frozen-thawed immature oocytes was higher in oocytes frozen with PG＋PEG(propylene glycol plus polyethylene glycol) than those frozen with single cryoprotectant and this index was almost 90% of unfrozen oocyte's index(2.39 vs. 2.66). The IVF rate of all frozen oocytes was very low(68% of unfrozen oocytes) and the IVF rate of frozen immature oocytes was slightly higher than that of frozen mature oocytes(39.0% vs. 34.4%), but polyspermic penetration was higher in frozen immature oocytes(21.9% vs. 19.1%). The cleavage rate after IVF of frozen-thawed oocytes was 9.3% for frozen mature oocytes and 11.3% for frozen immature oocytes and this rate was significantly lower(P<0.05) than that of control(60.7%). The development to 8-cell stage was greatly lower in frozen mature oocytes than in frozen immature oocytes. The results indicate that the use of PG plus PEG as cryoprotectant may be very effective for vitrification of porcine oocytes and the frozen-thawed immature porcine oocytes can be used fro in vitro embryo production based on IVM, IVF and IVC system.

• Reproductive and Developmental Biology
• /
• v.35 no.4
• /
• pp.475-478
• /
• 2011

In the present study, the effect of cysteine and NT or bisphenol A(BP) on in vitro aturation(IVM) of porcine oocytes were examined. COCs was cultured in NCSU-23 medium supplement with 10% FCS which had previously been covered with mineral oil and equilibrated in a humidified atmosphere of 5% $CO_2$ and 95% air at $38^{\circ}C$. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 medium supplement with 0.5~10.0 mM cysteine were $34.0{\pm}3.2%$, $36.0{\pm}3.5%$, $48.0{\pm}3.8%$, $22.0{\pm}3.2%$, respectively. The IVM rate of oocytes cultured in NCSU-23 medium supplement with 0.5~5.0mM NT for 48 hrs were $24.0{\pm}4.2%$, $18.0{\pm}4.9%$, $8.0{\pm}2.2%$, respectively. NT affects oocyte in vitro maturation rate in a dose-dependent. This result were significantly lower than the control group. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 medium supplement with 1.0 mM NT+5.0 mM cysteine($38.0{\pm}4.3%$) were significantly higher than that of NT treatment. The IVM rate of oocytes cultured in NCSU-23 medium supplement with 0.05~5.0 mM BP for 48 hrs were $20.0{\pm}4.7%$, $10.0{\pm}5.3%$, $6.0{\pm}3.2%$, respectively. The IVM rate of oocytes cultured in NCSU-23 medium supplement with BP was significantly lower cultured non supplement of BP ($44.0{\pm}3.5%$). BP affects porcine oocyte maturation rate in a dose-dependent manner. The IVM rate of oocytes cultured for 48 hrs in NCSU-23 medium supplement with 1.0 mM BP+5.0 mM cycteine ($32.0{\pm}3.2%$) were increased than that of BP treatment.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.3
• /
• pp.319-327
• /
• 2009

Follicular fluid meiosis-activating sterol (FF-MAS) has been suggested as a positive factor which could improve the oocyte quality and subsequent embryo development after in vitro fertilization. However, FF-MAS is a highly lipophilic substance and is hard to detect in studying the relationship between MAS and quality of oocyte maturation. The present study focused on the expression of lanosterol 14${\alpha}$-demethylase (LDM), a key enzyme that converts lanosterol to FF-MAS, on mouse oocyte maturation and its potency on development. LDM expression was strong in gonadotropin-primed germinal vesicle stage oocytes, weak after germinal vesicle breakdown (GVBD), and then strong in MII stage oocytes. The LDM-specific inhibitor azalanstat significantly inhibited oocyte fertilization (from 79.4% to 68.3%, p<0.05). Also, azalanstat (5 to 50 ${\mu}M$) decreased the percentage of blastocyst development dosedependently (from 78.7% to 23.4%, p<0.05). The specific inhibition of sterol ${\Delta}14$-reductase and ${\Delta}7$-reductase by AY9944 accumulates FF-MAS and could increase blastocyst development rates. Additionally, in the AY9944 group, the rate of inner cell mass (ICM)/ total cells was similar to that of in vivo development, but the rate was significantly decreased in azalanstat treatment. In conclusion, LDM, the key enzyme of FF-MAS production, may play an important role in fertilization and early development of the mouse embryo, especially in vitro.