• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.265-272
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• 2002

Forage breeding laboratory of National Livestock Research Institute, R.D.A. has made interspecific hybrids of Lolium multiflorum $\times$ L. pratensis and intergeneric hybrids of Lolium $\times$ Festuca since 1984, and has collected ecotypes of Italian ryegrass since 1991. Growth characteristics of these hybrids and ecotypes were researched, and then these clone lines were named. Among these clone lines, the several clones that have polen fertility, high cold-tolerance, and similar heading time were used for making synthetics, Naehan 6, 7, 8, 9, with polycrossing method in 1997. Field experiments were carried out to compare the mophological and agronomical characteristics and forage productivity and quality of the synthetics with those of Italian ryegrass varieties, Barmultra and Hwasan 101. in Suwon and Yonchun from 1999 to 2000. Heading time of the synthetics were 22th to 24th May that belong to late-mature types to be similar to that of Barmultra and Hwasan 101 in Suwon. The synthetics were 101 to 106 c3n in plant length, medium or thick in thickness of stem, dark peen in leaf color, broad and long in flag leaf, strong in lodging resistance, and excellent in regrowth. Winter survivals of the synthetics were no different from that of Barmultra or Hwasan 101 in Suwon, but better than that of Barmultra or Hwasan 101 in Yonchun where was -10 to -12$^{\circ}C$ of minimum average air temperature in January or February. Dry matter(DM) yields of the synthetics were similar to DM 8,238kg per ha of Barmultra in Suwon, but in Yonchun, were more 7 to 13% than DM 7,291kg per ha of Barmultra. Forage qualities, IVDMD, ADF, NDF and TDN of the synthetics were lower than those of Hwasan 101, but higher than those of Barmultra.

• Clinical and Experimental Reproductive Medicine
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• v.21 no.1
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• pp.31-41
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• 1994

Morphological estimation of human spermatozoa is complicated by the fact that there is great natural variation in shape. This natural variation in shapes makes it difficult to say which forms are associated with infertility and which are normal variations. Possibly post coital test or in vitro cervical mucus penetration tests will help to clarify this question by showing which sperm are capable of penetration. The purpose of this investigation was performed to assess distribution of various morphological abnormalities according to the ability of sperm to penetrate cervical mucus. The sperm-mucus penetration using hen's egg white as substituting mucus for human cervical mucus was done in 45 fertile men with normal semen analysis and 122 infertile men with abnormal seminal parameters more than one. The female partners of 122 infertile couples showed normal results in the female fundamental test for fertility. Conventional semen analysis was evaluated according to the WHO standard normal(l980). The detailed classification of the abnormal sperm was made according to David et al(l975). The vitality of the sperm samples determined by eosin yellow-nigrosin stainig according to the method of Eliasson(l977). Results were as follw; 1. The patients had significantly lower total sperm count, motility (%), normal morphology (%), viability and total functional sperm fractions(TFSF) than fertile donors. 2. The mean value of sperm penetration distance of the patients(28.69${\pm}$11.02mm) showed significantly lower than fertile donors(37.33${\pm}$5.49mm). And 43/45 fertile donors(95.5%) as well as 57/122 patients(46.7%) had over 30mm in sperm penetration distance respectively. While 2/45 fertile donors(4.5 %) and 65/122 patient(53.3%) had under 30mm in sperm penetration distance respectively. 3. The morphological abnormalities in fertile donors were significantly lower 23.04${\pm}$5.83% (head = 12.89${\pm}$4.98, neck=6.11${\pm}$3.83%, and tail=3.43${\pm}$2.65%), compared to 36.03${\pm}$14. 40% in patients(head = 15.98 8.60%, neck 11.20${\pm}$6.56% and tail=8.70${\pm}$6.55%). Also, 3 types of sperm abnormalities including head, neck and tail were significantly lower in patient than fertile donors, respectively. Both the patients and fertile donors showed higher distribution of sperm with abnormal head than abnormal neck and tail. 4. The mean morphological abnormalities(SP>30mm) of the patients(30.68 11.64%; head = 15.95${\pm}$9.35%, neck=8.14${\pm}$4.21 %, tail=6.56${\pm}$5.64%) were significantly lower compared to patients(40.72${\pm}$15.01 %; head=16.02${\pm}$7.69%, neck 13.89${\pm}$7.82%, tail=1O.58${\pm}$6.75%) under 30mm in sperm penetration distance. Also, both groups over 30mm and under 30mm in sperm penetration showed distance higher distribution of sperm with abnormal head than abnormal neck and tail. The morphological abnormalities of head did not show significant difference but abnormal neck and tail were significant difference between the over 30mm and under 30mm group in sperm penetration distance.

• Development and Reproduction
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• v.5 no.1
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• pp.47-52
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• 2001

Predetermination of sex in livestock of offpring is in great demand and is of critical importance to providing for the most efficient production of the animal ariculture. Such a sexing techlology would also enhance the economy of conventional artificial insemination(AI) and aid the porcine industry. The purpose of this study was to evaluate the efficiency of enriching X-bearing porcine sperm using discontinuous percoll gradients and PCR mefhod. Semen was collected from mature boars of proven fertility center (AI center KimHae). Sperm was leaded on the isotonic discontinuous percoll gradient and then it was centrifuged at 120 ${\times}$ g for 20 minutes. After centrifugation, sperm included in each fraction were recovered (7${\times}$10$^6$ sperms/ml) and then sperm genomic DNA was extractedfor the PCR. SRY gene was used to evaluate the ratio between X and Y sperm in the separated fractions. Ju viro ffrtilization wascarried out by adding the unseparated sperm (control) or separated (experimental poop) to the matured oocytes in TCM-199. Embryos for sex determination were obtained at 2 cell stage and then was used for SRY gene amplification. After centrifugation of discontinuous percoll gradient, the most motile sperm was obtained at 95% fiaction (94.4% ${\pm}$ 5.1%, p < 0.01). The PCR analysis evaluated that 30%, 50% and 65% fractions were Y sperm rich, whereas 80% and 95% fractions were X sperm rich. PCR analysis with each porcineembryo showed that 33.3% of control and 66.7% of experimental group were determined as female embryos. In conclusion, in vitro matured oocytes inseminated with sperms (95% fraction) prepared by percoll gradient centrifugation showed high fertilization rates and female embryos than control sperms.

• Journal of Genetic Medicine
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• v.7 no.2
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• pp.125-132
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• 2010

Purpose: Preimplantation genetic diagnosis (PGD), also known as embryo screening, is a pre-pregnancy technique used to identify genetic defects in embryos created through in vitro fertilization. PGD is considered a means of prenatal diagnosis of genetic abnormalities. PGD is used when one or both genetic parents has a known genetic abnormality; testing is performed on an embryo to determine if it also carries the genetic abnormality. The main advantage of PGD is the avoidance of selective pregnancy termination as it imparts a high likelihood that the baby will be free of the disease under consideration. The application of PGD to genetic practices, reproductive medicine, and genetic counseling is becoming the key component of fertility practice because of the need to develop a custom PGD design for each couple. Materials and Methods: In this study, a survey on the contents of genetic counseling in PGD was carried out via direct contact or e-mail with the patients and specialists who had experienced PGD during the three months from February to April 2010. Results: A total of 91 persons including 60 patients, 49 of whom had a chromosomal disorder and 11 of whom had a single gene disorder, and 31 PGD specialists responded to the survey. Analysis of the survey results revealed that all respondents were well aware of the importance of genetic counseling in all steps of PGD including planning, operation, and follow-up. The patient group responded that the possibility of unexpected results (51.7%), genetic risk assessment and recurrence risk (46.7%), the reproduction options (46.7%), the procedure and limitation of PGD (43.3%) and the information of PGD technology (35.0%) should be included as a genetic counseling information. In detail, 51.7% of patients wanted to be counseled for the possibility of unexpected results and the recurrence risk, while 46.7% wanted to know their reproduction options (46.7%). Approximately 96.7% of specialists replied that a non-M.D. genetic counselor is necessary for effective and systematic genetic counseling in PGD because it is difficult for physicians to offer satisfying information to patients due to lack of counseling time and specific knowledge of the disorders. Conclusions: The information from the survey provides important insight into the overall present situation of genetic counseling for PGD in Korea. The survey results demonstrated that there is a general awareness that genetic counseling is essential for PGD, suggesting that appropriate genetic counseling may play a important role in the success of PGD. The establishment of genetic counseling guidelines for PGD may contribute to better planning and management strategies for PGD.