• Asian-Australasian Journal of Animal Sciences
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• v.3 no.2
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• pp.125-133
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• 1990

The effect of dietary protein-energy restriction (PER) on the growth of long bone were examined in sheep during growing period and then following a cycle of reproduction. Three months-old female sheep were offered protein-energy restricted feed for 6 months (growing period), thereafter changed to normal nutritional conditions for 8 months (reproduction period). A half of animals in each group took pregnancy, parturition and lactation. The nutritional restriction reduced the growth in bone diameter more than that in bone length. Compensatory growth resulting from the removal of the nutritional restraint strongly occurred in bone diameter, especially the bone cortical width, as compared to bone longitudinal growth. A cycle of reproduction severely decreased the growth in the bone cortical width relative to that in the bone width, and little effect was found on the growth in bone length and bone mass. The depression of bone development by pregnancy and lactation tended to exhibit severer in animals having received normal nutrition than in those having received PER. Bone mineral density was not affected by the nutritional restriction. A cycle of reproduction had an adverse effect on the mineral density between in animals having received normal nutrition and in those having received PER.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.1
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• pp.40-49
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• 2019

Chronic and unpredictable stress can disrupt the female reproductive system by suppression for secretion of gonadotrophin-releasing hormone (GnRH) and gonadotrophin, resulted in ovarian malfunction and infertility. In the recent days, kisspeptin has been highly highlighted as a hypothalamic peptide which directly stimulates synthesis and release for GnRH. However, in spite of the key role of kisspeptin in the female reproductive system, little information is still available on the changes of its expression during ovarian cycle under stressed condition. Therefore, we induced chronic and unpredictable stress series to the female mice to analyze kisspeptin expression in the brain and ovary. Stressed mice exhibited changes of behavior and body weight gain during the stress assessment, which suggested that the present stress model in mice was successfully established. In the brain level, kisspeptin expression was attenuated than control. In the ovary level, the stressed mice displayed irregularly shrunk oocytes with broken zona pellucida throughout the follicle stages, pyknotic granulosa cells, decreased number of developing follicles and increased number of atretic follicles than the control. In case of kisspeptin expression in the whole ovary tissue, the expression level was decreased in the stressed mice. In detail, the less intensity of kisspeptin expression in the antral follicles phase was observed in the stressed mice than control mice, indicating that local function of kisspeptin during ovary cycle is highly associated with development of ovarian follicles. We expect that the present study has important implications for the fields of reproductive biology.

• Animal cells and systems
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• v.12 no.4
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• pp.231-240
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• 2008

The gorgonian coral Anthoplexaura dimorpha Kukenthal, 1908(Gorgonacea: Octocorallia) is abundant in Jejudo Islands, Korea. To investigate the sexual reproduction of this species, we surveyed the morphology and cycle of gametogenesis. 5-6cm long fragments from 3-7 randomly chosen colonies were collected monthly at a depth of 12-24m in the water surrounding Munseom from August 2003 to August 2005. This species was gonochoric with sex ratio of 1.86:1(female to male), and had one annual reproductive cycle affected by elevation of seawater temperature. Oogenesis was longer than spermatogenesis as 12 months in female and 6 months in male. The planulae were not observed from the field survey and histological sections, which suggested broadcast spawning for the reproductive mode in this species. The possible spawning events may occur after the seawater temperature attain to the annual peak in September.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.37-37
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• 2002

The success of embryo cloning depends on numerous factors; interaction between recipient ooplasm and donor nucleus, nuclear reprogramming, oocyte activation, and donor cell cycle and type. In this study, the cell cycle and apoptosis of bovine fetal fibroblast as a donor cell for embryo cloning were evaluated following different activation treatments. (omitted)

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.7
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• pp.919-923
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• 2004

Ultrasonographic study was undertaken to establish the echogenecity and size of reproductive organs of 18 cycling buffaloes of different parities and compared with the sizes measured by palpation per rectum at estrus (day 0), met estrus (day 2), mid diestrus (day 10) and late diestrus (day 16). The overall mean size of cervix, uterine body, right horn, left horn, right ovary and left ovary measured by palpation per rectum were 2.70$\pm$0.43, 2.36$\pm$0.36, 2.17$\pm$0.37, 2.12$\pm$0.38, 2.63$\pm$0.41 and 2.72$\pm$0.37 cm, respectively. The corresponding ultrasonographic observations were 2.10$\pm$0.40, 1.85$\pm$0.30, 1.73$\pm$0.36, 1.64$\pm$0.37, 2.16$\pm$0.36 and 2.29$\pm$0.38 cm respectively. Variations in the size of genitalia due to stages of estrous cycle were non-significant. The size of genitalia measured by palpation per rectum was significantly higher (p<0.05) than by ultrasonography. However, there was linear positive correlation (r=+0.87) in the measurements by the two techniques. The ultrasonographic characteristics of tubular genitalia revealed different echogenic gray shades around the nonechogenic (black) central area of lumen depending upon the stage of cycle. The ovarian stroma appeared as hyperechoic (white) area with nonechogenic (black) follicle. The corpus luteum (CL) exhibited different echogenic texture viz. grayish black, grayish granular and grayish white at met estrus, mid diestrus and late diestrus, respectively. Therefore, ltrasonography can be effectively employed to record the exact size and echotexture of the buffalo genitalia during different stages of estrous cycle.

• Korean Journal of Animal Reproduction
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• v.17 no.4
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• pp.279-285
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• 1994

The objective of the present study was to characterize the cell cycles of granulosa cell populations during follicular maturation in cattle by using flow cytometer. Granulosa cells were isolated from bovine preovulatory antral follicles of F1(>10mm), F2(5~20mm), F3(3~4mm) and F4(1~2mm) diameter and fixed and stained with fluorochromes that selectively bine to DNA. Flow cytometer equipped with a laser excitation system was used to analyze the intensity of fluorescence from stained cells. Forward angle light-scatter(FSC) and 90$^{\circ}$light-scatter(SSC) signals were adopted to measure the size and the granularity of granulosa cells. As a results of FSC/SSC analysis, granulosa cell populations(G1 phase of cell cycle) from each follicle were relatively regular in size and granularity, regardless of follicular size. However, their distribution in granularity was greater than that in size. Most of granulosa cell populations collected from each follicle were distributed in G0/G1, S and G2/M phases. As the follicles approached to ovulation the percentage of cells in the proliferative phases of cell cycle (S and G2/M) decreased significantly, but there was a concomitant increase in the percentage of granulosa cells in G1 phase. Therefore, these data indicate the proportion of main populations to cell cycle of granulosa cells may be changed from proliferative phase to G1 phase during follicular maturation in cattle.

• Korean Journal of Animal Reproduction
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• v.13 no.3
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• pp.179-187
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• 1989

The experiment was carried out to study the profile of uterine specific protein during early pregnancy in sows and to test it's immunosuppressive activity. Uterine protein samples were obtained by flushing the uterine horn on Day 3, 6, 9, 12 and 15 of the estrous cycle and the pregnancy respectively and the protein concentration of each sample was determined. The change of uterine protein was examined by sodium dodecyl sulfate(SDS)-PAGE. The immunosuppressive activity of uterine secretory protein was investigated according to the lymphocyte blastogenesis response to mitogen. The results of this experiment are summarized as follows ; 1. The uterine protein during estrous cycle and early pregnancy was relatively constant up to Day 9, but increased on Day 12. Maxium total protein values were found on Day 15. The concentration of serum proteins were about 82-95 mg during estrous cycle, but decreased to about 70-82 mg during early pregnancy. 2. The proteins components similar electrophoretic patterns(PAGE) that were no differences (band ; a, b, c, d, e, f, g, I) on Days 3, 6 and 9 of the estrous cycle and pregnancy. But there were more 2 bands specifically on Day 12 of the pregnancy and on Day 15 of estrous cycle and showed more 4 bands on Day 15 of early pregnancy. They seemed to be acidoprotein and their average molecular weight were 38,000, 22,300 and 12,600. 3. When uterine protein were added 500$\mu\textrm{g}$/ml, there was no immunosuppresive activity on Day 3 of estrous cycle and lymphocyte blastogenesis was slightly suppressed on Day 3 of pregnancy. The immunosuppressive activity on Day 9 of estrous cycle and pregnancy appeared in 500$\mu\textrm{g}$/ml and 150$\mu\textrm{g}$/ml, respectively the uterine protein on Day 12 and 15 showed immunosuppresive activity, which at the level of 150$\mu\textrm{g}$/ml during non-pregnancy and at the level of 100 to 125$\mu\textrm{g}$/ml during early pregnancy, respectively.

• Korean Journal of Animal Reproduction
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• v.11 no.1
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• pp.33-41
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• 1987

The cycle of the seminiferous epthelia in the testis of matured Korean Native Cattle was divided into eight stages. The results were summarized as follows: 1. Type A spermatogonia a, pp.ared twice as many at stage 2 as compared to stage 1, while maximum numbers were the average of 2.8 at stage 2. The intermediate and Type B spermatogonia were found during the stage 3 to 8, stage 6 to 8, respectively. The leptolene primary spermatocytes were not observed during the stage 5 to 7, while the pachytene primary spermatocytes were shown the least in number at stage 4, the secondary supermatocytes could be seen only at stage 4 and the round spermatids were not observed at stage 3, 4. 2. The relative frequencies of the eight stages of the cycle of the seminiferous eptithelia were 24.9, 14.2, 19.0, 6.3, 3.7, 7.9, 10.3 and 13.9%, respectively. 3. Some of the nuclei of Sertoli cells transformed from the "parallel" type to the "perpendicular" type. This evolution took place from stage 1 to 5, when the number of "perpendicular" type nuclei reached a peak and the number was decreased in the rest of the stages.sed in the rest of the stages.

• Korean Journal of Animal Reproduction
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• v.16 no.2
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• pp.133-139
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• 1992

The study was conducted to find out the changes of progesterone and 20$\alpha$-dihydroprogesterone (20$\alpha$-OHP) levels during the oestrous cycle in Korean native goats. 4 cyclic goats were offered for this experiment. Blood samples were taken from jugular vein on day 0, 1, 3, 5, 7, 9, 11, 13, 15, 17 and 19 during the oestrous cycle, then the next oestrous day. The serum levels of progesterone and 20$\alpha$-OHP were measured by radioimmunoassay. The progesterone concentration in seurm of the cyclic goats was 0.29$\pm$0.06ng/ml on the first day of oestrous (day 0), increased to 5.29$\pm$0.73ng/ml on day 9, reached to a peak level of 5.73$\pm$0.61ng/ml on day 13, and thereafter decreased to 0.35$\pm$0.30ng/ml on day 1. The serum level of 20$\alpha$-OHP during the oestrous cycle was 0.42$\pm$0.33ng/ml on day 0 and then decreased to 0.28$\pm$0.01ng/ml on day 5. This basal level was maintained until day 13, increased gradually, and reached a peak level of 0.62$\pm$0.05ng/ml on day 19. From the above results, it was suggested that the enzyme 20$\alpha$-hydroxysteroid dehydrogenase(20$\alpha$-HSD) catalyzing the conversion of progesterone to a biologically inactive steroid, 20$\alpha$-OHP, should be active in the luteal cells during the oestrous cycle in Korean native goats.

• Korean Journal of Animal Reproduction
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• v.20 no.3
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• pp.307-313
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• 1996

This study was conducted to investigate the effect of S-phase synthronized nuclear transfer on the development of nuclear transplant bovine embryos. A blastomere derived from the 16~32 cell stage bovine embryos was transferred into an enucleated metaphase II(MII) oocytes or activated S-phase eggs. From the MII-phase and S-phase nuclear transfer, 6.3%(4/63) and 13.8%(9/65) of nuclear transplant embryos developed to the blastocyst stage, respectively. In the S-phase nuclear transfer, maximal proportion of embryos developed to the blastocyst stage(16.6%) was obtained after the recipient cell was activated 8 h prior to receving a donor nucleus. MII-phase nuclear transplant embryos showed the PCC state of their nuclear at 1.5~2 h after fusion, whereas, S-phase nuclear transplant embryos did not undergo PCC. The result of this study suggests that if blastomeres of unknown cell-cycle-stage are used, S-phase nuclear transplantation through the activation of enucleated oocytes prior to fusion enhances development of nuclear transplant embryos. This result also suggests that the interval time from oocyte activation to cell fusion may affect the development of nuclear transplant embryos.