• The Korean Journal of Malacology
• /
• v.31 no.2
• /
• pp.113-121
• /
• 2015

Gametogenesis, mating behaviour and spawning of Octopus ocellatus were investigated by histological study. This species is dioecious, and showed a protandry phenomenon. Ooogenesis (in females) and spermatogenesis (in males) can be classified into 3 stages, respectively. O. ocellatus copulates in one of two ways: a male may leap upon a female, mounting her mantle, or a male may sit near the female and extend the hectocotylized third right arm toward her. Spawning occurred between April and June in females, and between March and May in males of O. ocellatus. The spawning period was once a year and the peak took place between May and June. A number of flatened follicle cells, which were attached to an oocyte, were involved in vitellogenesis in the cytoplasm of the vitellogenic oocyte (maturing oocyte), and formation of chorion membrane (secondary egg membrane) of the ovarian eggs. Fecundity per female closely related to GSI was 294-660 eggs (average, 429 eggs). The diameters of the ovarian eggs surrounded by chorion membrane were approximately in the range of 10.10-2.50 mm. Each ovarian egg laid by a female was connected to an egg string. Each egg string was 1-5.5 cm (average 3.6 cm). The total number of eggs laid by a female of this species ranged 218-314, the egg sizes were independent to the size of female adult. this species has a life mode showing some special reproductive characteristics of an annual semelparity as shown in Octopodidae species because we have never seen a female spawning a second time.

• Korean Journal of Veterinary Research
• /
• v.39 no.3
• /
• pp.455-462
• /
• 1999

This study was designed to investigate the number of the growing and mature follicles in each stage of estrus cycle in mature rats. Eighteen mature rats(Sprague-Dawley, initially 190~230gm) were randomly alloted into 4 groups(proestrus, estrus, metestrus, and diestrus) according to estrus cycles. The uteri and ovaries of rats were collected and then alternative sections of paraffin embedding ovaries were stained with H-E. Numbers of large, middle and small follicles or only large and middle follicles from secondary and tertiary follicles were investigated by LM photography of preparations. Small follicles were defined as secondary follicles with 2~5 cell layers of granulosa cells surrounding the oocyte, and middle follicles were defined as secondary follicles with more than 5 cell layers or with early signs of antral cavity or with more than one small cleft on either side of the oocytes and large follicles were defined as tertiary follicles with a single medium or large antral cavity. The number of follicles in a pair ovary per rat was appeared to be ranged from 207 to 370 and the mean number of these follicles was $270.4{\pm}52.6$ and the mean number of follicles per ovary was $134.9{\pm}32.0$. The mean number of large, middle and small follicles per ovary was appeared to be $16.4{\pm}4.4$($12.2{\pm}3.3%$), $36.2{\pm}8.6$($26.8{\pm}6.4%$), and $82.7{\pm}24.0$($61.3{\pm}17.8%$), respectively. The mean number of large and middle follicles in each stage group of estrus cycle was appeared to be $17.8{\pm}2.1$ and $38.3{\pm}7.4$ at proestrus stage group, $15.7{\pm}5.2$ and $38.0{\pm}10.0$ at estrus stage group, $16.5{\pm}3.5$ and $33.8{\pm}7.0$ at metestrus stage group, $16.7{\pm}5.8$ and $29.7{\pm}5.5$ at diestrus group, respectively. In histological findings of large follicles during each estrus cycle, the large follicles in proestrus group contain single small antrum, thick granulosa cell layers, and were $300{\sim}500{\mu}m$ in diameter and were growing follicles with PCNA-positive cells in the granulosa cell layers, and other luteinizing follicles of proestrus cycle stage were decreased in size and were thicker in wall thickness and more luteinized than those in metestrus and diestrus stage groups. The large follicles in estrus stage group contain thick granulosa cell layers and nonprominent cumulus-oocyte complexes in antrum, and were $400{\sim}700{\mu}m$ in diameter and were growing follicles with PCNA-positive cells in the granulosa cell layers. The large follicles in metestrus and diestrus stage groups contain enlarged antrums, thinner layers of walls and prominent cumulus-oocyte complexes, and were $700-950{\mu}m$ in diameter, and were nongrowing follicles without PCNA-positive cells or another large follicles contain cells with dark stainability and distinct boundary.

• Reproductive and Developmental Biology
• /
• v.29 no.2
• /
• pp.121-125
• /
• 2005

The present study was performed to determine the ability of canine oocytes to achieve nuclear maturation according to oocyte diameter and different culture environments. All of the collected oocytes were classified by grade 1 to 3 and by their diameters such as $<100{\mu}m,\;<100{\mu}m\;to\;<110{\mu}m,\;<110{\mu}m,\;to\;<120{\mu}m,\;>120{\mu}m,$. Oocytes were cultured in culture medium supplemented with $10\%\;FBS,\;0.4\%\;BSA,\;10\%$ porcine follicular fluid (pFF), $10\%$ canine serum (CS), or $10\%$ canine estrus serum (CES). The mean number of oocytes recovered from estrus status ovaries was significantly higher than that of anestrus status ovaries (p<0.01). The maturation rate of grade 1 oocytes $(>120{\mu}m)$ was significantly higher than that of the other groups (p<0.05). Nuclear maturation to MI to MII in diameter of $>110{\mu}m$ groups was significantly higher than that in $<100{\mu}m$ group (p<0.05). The oocytes cultured in $10\%$ FBS­supplemented group were significantly higher rate of GVBD compared to the other supplemented groups (p<0.05), and oocytes maturation to MI to MII in $10\%$ FBS-, $0.4\%$ BSA-, and $10\%$ pFF-supplemented groups were significantly higher than those in $10\%$ CS-supplemented group (p<0.05). Based on these results, the estrus status and the size of oocyte affect positively to improve nuclear maturation of canine immature oocytes in vitro. Among several protein sources, porcine follicular fluid was the most effective supplementation to culture medium to achieve higher in vitro maturation rate.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.2
• /
• pp.174-178
• /
• 2004

The objectives of this study were to investigate the ovarian responsiveness of juvenile calves to exogenous gonadotropin treatments and to establish the oocyte retrieval technique for prepubertal heifers. Three 78-day-old calves were treated with 4 doses (40, 30, 30 and 30 mg) of FSH (Folltropin V) at 12 h interval up to 229 day-old. Surgical oocyte retrieval was performed 24 h after the last injection of FSH. Calves with good ovarian responses to FSH treatment had an average ovarian size of $5{\times}3$ cm compared to $3{\times}2$ cm in the less-responsive animals. Large variations were observed in the number of total follicles ($51{\pm}45$), aspirated follicles ($39{\pm}36$), oocytes recovered ($23{\pm}25$) and usable oocytes recovered ($11{\pm}19$) during 78 to 229 day-old. Oocytes derived from prepubertal calves had significantly lower maturation rate than those from cows (34 vs. 100%, p<0.05). Mean diameters of calf oocytes ($144{\pm}1{\mu}m$) and ooplasm ($110{\pm}1 {\mu}m$) were significantly lower than those of cows ($149{\pm}1$ and $25{\pm}1{\mu}m$, respectively). The diameter of the ooplasm also increased significantly after in vitro maturation (IVM) ($108{\pm}1$ vs. $112{\pm}1{\mu}m$). However, further studies are required to optimize the IVP system for the oocytes derived from prepubertal heifers.

• Clinical and Experimental Reproductive Medicine
• /
• v.26 no.3
• /
• pp.369-375
• /
• 1999

Objective: To evaluate the effect of serum obtained before and after treatment for endometriosis on in vitro fertilization and development of two cell mouse embryo. Design: Pretreatment and posttreatment comparoson of fertilization of mouse oocyte and embryo development in serum supplement from patients with endometriosis; result were compared using Stuent T-test analysis. Method: Infertility Clinic, Department of Obstetrics and Gynecology, Collage of Medicine, Won kwang university, Korea. Patients was chosed eleven consecutive women with endometriosis. Interventions was all patient underwent laparoscopic or conservative surgery. This was followed by a 6-month course of burserelin acetate $900{\mu}g/d$. Main outcome was measured total number of fertilization and embryo that was fertilization after 24 hours and reached blastocyst stage after 72 hours of incubation were compared before and after treatment. Result: Before treatment, 47% of the oocyte were fertilized and 31% of the embryo reached blastocyst stage. After treatment, Significantly more fertilized and Significantly more embryo developed to blastocyst on the stage I and II of endometriosis. Conclusion: The fertilization and embryo toxicity of serum samples from patients with endometriosis is lost after treatment.

• Journal of Embryo Transfer
• /
• v.28 no.4
• /
• pp.361-371
• /
• 2013

The present study assessed the effect of FSH and LH on oocyte meiotic, cytoplasmic maturation and on the expression level and polyadenylation status of several maternal genes. Cumulus-oocyte complexes were cultured in the presence of FSH, LH, or the combination of FSH and LH. Significant cumulus expansion and nuclear maturation was observed upon exposure to FSH alone and to the combination of FSH and LH. The combination of FSH and LH during entire IVM increased the mRNA level of four maternal genes, C-mos, Cyclin B1, Gdf9 and Bmp15, at 28 h. Supplemented with FSH or LH significantly enhanced the polyadenylation of Gdf9 and Bmp15; and altered the expression level of Gdf9 and Bmp15. Following parthenogenesis, the exposure of oocytes to combination of FSH and LH during IVM significantly increased cleavage rate, blastocyst formation rate and total cell number, and decreased apoptosis. In addition, FSH and LH down-regulated the autophagy gene Atg6 and upregulated the apoptosis gene Bcl-xL at the mRNA level in blastocysts. These data suggest that the FSH and LH enhance meiotic and cytoplasmic maturation, possibly through the regulation of maternal gene expression and polyadenylation. Overall, we show here that FSH and LH inhibit apoptosis and autophagy and improve parthenogenetic embryo competence and development.

• Journal of Embryo Transfer
• /
• v.29 no.1
• /
• pp.35-41
• /
• 2014

Laparoscopic ovum pick-up (LOPU) is a convenient method for collecting oocytes in small ruminants. LOPU has the advantage of being a less invasive means of oocyte collection, thereby allowing for a repeated usage of the oocyte donor animals. A total of 25 Korean black goats were used in the winter season (December to February) and LOPU was applied to the goats which had been treated for superovulation more than two times during the last twelve months. Estrus was synchronized with an intravaginal insert containing 0.3 g progesterone for 10 to 12 days. Ovaries were hyperstimulated with eCG 1,000 IU oneshot, FSH with eCG (50 mg / 1,000 IU; 70 mg / 500 IU; 70 mg / 1,000 IU) oneshot or FSH multiple-shot with eCG oneshot ($20mg{\times}6/300IU$) given intramuscularly 72 h prior to LOPU. For these groups, the number of follicles (mean ${\pm}$ SEM) observed which developed to larger than 2 mm in diameter were $1.6{\pm}2.5$, $4.3{\pm}3.1$, $5.5{\pm}4.2$, $6.6{\pm}2.1$ and $8.8{\pm}7.8$, respectively. Oocytes were aspirated by using OPU needles and a vacuum pump. The overall oocyte retrieval rates were 41.4%. Oocytes were matured in TCM-199 supplemented with 10% (w/v) bovine serum albumin + $10{\mu}g/ml$ FSH + $1{\mu}g/ml$ $17{\beta}$-estradiol for 27 h at $39^{\circ}C$ in 5% $CO_2$ in air. Oocytes were parthenogenetically activated by ionomycin combined with 6-diethylaminopurine (6-DMAP). Total oocyte maturation and cleavage rate were 67.3% and 78.8%, respectively. In summary, LOPU is a useful oocyte collection method in Korean black goats that can provide immature oocytes for transgenesis or nuclear transfer.

• Clinical and Experimental Reproductive Medicine
• /
• v.30 no.4
• /
• pp.333-340
• /
• 2003

Objective: This study was performed to examine the maturation and the development to the blastocyst stage of immature oocytes collected from patients with high risk of ovarian hyperstimulation syndrome (OHSS). Materials and Methods: Cumulus-oocyte complexes (COCs) were collected following only HCGpriming for non stimulated IVF-ET cycles of the patients. At the time of oocyte collection, COCs were classified into three groups in accordance with their appearance (Group I: oocytes with dispersed cumulus cells; Group II: oocytes with compacted cumulus cells; Group III: oocytes with sparse cumulus cells). The in vitro maturation and blastocyst development rates of the COCs were compared among these groups. From August 2001 to June 2002, 48 IVM/IVF-ET cycles from 42 patients (mean age: $32.4{\pm}3.8$ years) were performed. To prevent the occurrence of OHSS, the patients were primed with 10, 000 IU HCG alone 36 h before oocyte collection without gonadotropin stimulation. Oocytes were aspirated on cycle days from 7 to 13. The normal COCs were classified into three groups according to their appearance. The aspirated immature oocytes were cultured in YS maturation medium containing 30% (v/v) human follicular fluid (HFF), 1 IU/ml FSH, 10 IU/ml HCG and 10 ng/ml rhEGF. Fertilization was induced by intracytoplasmic sperm injection (ICSI). All zygotes were co-cultured with cumulus cells in $10{\mu}l$ YS medium containing 10% HFF until day 7 after oocyte collection. Blastocyst transfer was performed on day 5 after ICSI. Results: Th e mean number of oocytes cultured in the IVM/IVF cycles was $24.7{\pm}10.6$. Of 1185 COCs, those assigned to Group I, II and III were 470 (39.7%), 414 (35.0%) and 301 (25.4%), respectively. The maturation rate (94.5%, 444/470, p<0.05) in Group I was significantly higher than those of Group II (62.8%, 260/414) and Group III (73.1%, 220/301). Especially, 30.9% of COCs in Group I (145/470) was matured on the day of oocyte aspiration. There were no differences in the rates of fertilization and cleavage among the three groups. The development rate to the blastocyst stage in Group I (54.6%, 206/377, p<0.05) was also significantly higher than those in Group II (33.0%, 68/206) and Group III (30.1%, 52/173). Twenty-four clinical pregnancies (50.0%) was obtained and 22 pregnancies (45.8%) are ongoing. Implantation rate in the present study was 24.6%. Conclusion: These results suggest that there is a positive correlation between the appearance of COCs and the developmental competence of the immature oocytes in non stimulated IVM/IVF cycles.

• Journal of fish pathology
• /
• v.16 no.3
• /
• pp.215-217
• /
• 2003

This study examined whether the connexin (Cx) is an essential protein during oocyte maturation in the ovary of the goldfish (Carassius auratus). In mature female goldfish ovaries, at late vitellogenic stage, human insulin-like growth factor-I (IGF-I; 20 M) and human chorionic gonadotropin(hCG; 20 IU/㎖) were injected. Twelve hr after the injection, mature female goldfish ovaries were removed and stored at -80C until analysis by RT-PCR. From the goldfish Cx43 cDNA sequence (GenBank accession number AB078505), two degenerate primers were designated. In vivo, 12 hr after the treatment with hCG, goldfish Cx43 mRNA expression level was increased, while the levels of IGF-I was not changed. Goldfish Cx43 mRNA expressed after, but not before the hCG treatment. These results suggest that Cx43 mRNA was judged to be a gene, which was transcribed during oocyte maturation induced by hCG.

• Journal of fish pathology
• /
• v.16 no.2
• /
• pp.125-129
• /
• 2003

Conncxin (Cx) is an important and essential protein induction of oocyte maturation, which is present in almost all mammalian tissucs except cirulating blood cells and adult skeletal museles. In this study, goldfish Cx43 cDNA sequence is available in GenBank under the accession number AB078505. Homology analyses using the GenBank and EMBL general database searches indicated that goldfish Cx43 cDNA has a high homology with carp Cx43 (95.1% identity), zebrafish Cx43 (90.5% identity), and chicken Cx43 (81.9% identity). Goldfish Cx43 is similar to the Cx family in its general features, and all the typical Cx consensus sequences are also found. Moreover, significantly increased Cx43 transcrpts were observed in mature goldfish (GSI; 18.3-21.7) pituitary and ovary when compared with immature goldfish (GSI; 4.9-6.0). Cx43 transeripts were weakly detectrd in both liver and kidney of immature and mature goldfish. There is possible that Cx43 nctivity was relation to oocyte maturation in the goldfish.