체세포 복제기술을 이용한 복제가축 생산 기술은 1997년 전 세계적으로 이슈가 되었던 복제 면양 “Dolly”의 탄생을 계기로 여러 나라에서 소, 돼지, 말, 고양이, 개 등 많은 포유류에서 산자 생산에 성 공하였으며 우리나라의 체세포 복제 기술은 기술 선진국 대열에 들어서고 있다. 그러나 복제기술은 아 직까지 높은 유산율과 폐사율 등 해결해야 할 많은 근본적인 문제점 등이 있어 연구해야 할 분야는 적 지 않다고 하겠다. 체세포 복제 동물 생산기술은 당초에는 능력이 우량가축의 생산과 확대 및 조기증식 을 목적으로 이용되고 왔으나, 체세포 내로 우리가 원하는 유전자를 도입시키거나 없애는 기술 (knock-in과 knock-out)의 발달로 바이오장기 생산용 형질전환 복제 돼지의 생산을 목적으로 널리 이 용되고 있다. 또한, 최근에는 멸종위기에 있는 희소동물 유전자원을 멸실 이전에 동결 보존된 체세포를 이용하여 복원에 활용할 뿐 아니라 마약탐지견 생산 등 특수한 목적으로 활용되는 동물을 생산하는 기 술로서 기여하게 된다면 산업적으로 활용할 수 있는 분야가 더욱 확대될 것으로 기대된다. 따라서 체세 포 복제기술은 식용보다는 오히려 다양한 목적으로 복제동물을 생산하게 되면 산업적으로 활용할 수 있 는 가능성이 높을 것으로 기대되고 있다.

The objective of this study was to analyze the accuracy of estrus detection of heat detector and analysis of estrus behavior (mounting and mounted), and the evaluation of conditions required for improving reproductive efficiency in Holstein dairy cows fitted with a estrous detector. The heat detection system consists of estrous detector based on wireless sensor and an electric bulletin board displayed estrus behavior data. When cow mounting other cows, the accuracy of estrus behavior displayed an electric bulletin board were 87.5% (mounting other cows only), 100% (mounting other cows but not standing), 80.0% (mounting other cows with standing for 1∼4 seconds), 90.0% (mounting other cows but not standing for 1∼4 seconds), 80% (mounting other cows with standing for more than 5 seconds) and 90.0% (mounting other cows but not standing for more than 5 seconds). When cow mounted other cows, the accuracy of estrus behavior displayed an electric bulletin board were 100% (mounted other cows but not standing), 100% (mounted other cows with standing for 1∼4 seconds), 100% (mounted other cows but not standing for 1∼4 seconds) and 100% (mounted other cows with standing for more than 5 seconds). Circadian distribution of first observed in estrus were 59.1% (am 8∼pm 6) and 40.9% (pm 6∼am 8). Distribution for the number of estrus behavior were 40.9% (less than 3 times), 36.4% (4∼6 times) and 22.7% (more than 4 times). The conception rates relative to interval from first estrus behavior to insemination for estrus periods were 23.1% (less than 11 hours) and 55.6% (12∼20 hours).

Embryo transfer (ET) technology is of high importance in modern cattle breeding programs. ET is one step in the process of removing one or more embryos from the reproductive tract of an outstanding donor female and transferring them to one or more recipient females. Embryos also can be produced in the laboratory via techniques such as in vitro fertilization (IVF). But the actual transfer of an embryo is only one step in a series of processes that may include some or all of the following: superovulation and insemination of donors, collection of embryos, isolation, evaluation and short-term storage of embryos, micromanipulation and genetic testing of embryos, freezing of embryos and embryo transfer. Cryopreservation and direct transfer of frozen-thawed embryos is common-place with pregnancy rates near that of fresh embryos. Polymerase chain reaction (PCR) technology is currently being used for sexing embryos, and this technology will be used for “embryo diagnostics” and “embryo genomics” in the future. Although, many limitations and problems remain to overcome, these and other new technologies promise to change livestock breeding drastically in the next decade.

This study aimed to improve the reproductive efficiency of dairy herds by comparison and analyzing estrous appearance rate, conception and non-conception rate according to the stage of lactation using the lactation and reproductive records of average (less than 10,000 liters milk in 305 days) and high yielding (more than 10,000 liters milk in 305 days) Holstein cows (n=102). Milk production and reproduction data were collected between January 2010 and December 2012 from Holstein cows kept in the commercial dairy farms. Average (n=32) and high yielding (n=24) Holstein cows used to analyze the relationship between milk yield and reproductive performance. Our results showed that estrous appearance rate according to the stage of lactation was 25.0% (30∼59d), 40.6% (60∼ 89d), 25% (90∼110d) and 9.4% (>111d) in average yielding cows and 16.7% (30∼59d), 20.8% (60∼89d), 12.5% (90 ∼110d) and 50.0% (>111d) in high yielding cows, respectively. Conception rate according to the stage of lactation was 87.5% (30∼59d), 61.5% (60∼ 89d), 75.0% (90∼110d) and 66.7% (>111d) in average yielding cows and 25.0% (30∼59d), 0% (60∼89d), 33.3% (90∼ 110d) and 50.0% (>111d) in high yielding cows, respectively. Days between parturition and conception was 23.7% (<149d), 0% (150∼209d) and 0% (>210 d) in average yielding cows and 69.0% (<149 d), 77.8% (150∼209d) and 38.9% (>210d) in high yielding cows, respectively. Conception rate from 110 days postpartum in high yielding cows was 41.7% (110∼150d), 50.0% (151∼180d) and 50.0% (>181d). Body condition score (BCS) in 120 days postpartum was 2.64±0.1 in average yielding cows and 2.28±0.1 in high yielding cows, respectively.

today's dairy production management systems, reproductive efficiency affects the income of any farm by influencing overall milk production, genetic gain, amount of replacement heifers, and wise cullling decisions. Nutrition, management, and genetics play a major role achieving this maximum herd-reproductive performance. Several reports using trace minerals on the diet of cattle have shown reproductive effects. The main justification for using blocks, to provide deficient nutrients is, therefore, their convenience for packaging, storage, transport and ease of feeding. Dairy cattle are annually exposed to prolonged periods of elevated humidity and heat which reduce feed intake and reproductive performance. The objectives of the present study were to evaluate the effects of mineral on reproductive performance of dairy cows during Summer. The experimental group of cows had access ad libitum to the mineral lick in the following composition : Zn, Fe, Mn, Cu, I, Co, Se. Environmental heat load was described using the THI (temperature humidity index) because thermoregulation in cows is affected by both Temp and RH. The THI was calculated: THI=(0.8×Temp)+[RH×(Temp— 14.4)]+ 46.4. All cows were monitored for estrus twice daily in the morning and late afternoon. And any animal found in estrus was artificially inseminated. Pregnancy diagnosis was performed via ultrasonography at 45 to 70 d after insemination. The visitation and intake of mineral were higher with the maximum THI. The mean intake of mineral block was 23.1 kg in Summer and 17.7 kg in other seasons. The reproductive performance was considerably improved by mineral supplementation. The factors influencing consumption of mineral mixtures include: soil fertility and forage type, available energy and protein, individual requirements, salt content of the water, palatability of mineral mixture, availability of fresh minerals and physical form of minerals. These results show that minerals have a great impact on animal's reproductive physiology.

Artificial insemination and embryo transfer is one of the most important factors affecting to the production of fawn from deer nuclear transfer in the field of deer farms. This study* was conducted to establish the production technology of nuclear transfered embryo in deer. For estrus synchronization or superovulation tretments in flower deer and elk, each 10 does were inserted into the vagina for 14 days with CIDR (Pfizer New Zealand Ltd., NZ) for elk and Ring-CIDR (Bioculture Co., Ltd., Korea) for flower deer, and then those inserted devices were removed. The estrus synchronization of each 6 does were induced by the intramuscular injection of PGF2α (25 mg/head) and PG600 (hCG 200IU + PMSG 400IU, Intevet, Holland). Then, the superovulation of each 4 does of flower deer and elk was induced by additional injection of FSH (200 mg/ head) twice with an interval of 24 hours , respectively. Follicular oocytes were collected from each 2 does superovulated after 48 hours since the injection of PG600 and FSH. In the meantime, the ovarian response and the number of the collected ovarian follicles were investigated with the surgical operations. As a result, the average number of the collected ovarian follicles were 8.5 and 9.0 in flower deer and elk, respectively. The ovarian follicles collected from each two does were cultured in vitro for 48 hours with m-DMEM medium, and then the cell fusion was carried out after the nuclear transfer by the antler cell. As a result, 5 out of 18 ovarian follicles collected from 2 elk does were reached on the MII stage, but there was no generation resulting from the nuclear transferred embryos by the antler cell after enucleation. In 2 flower does, 7 out of 17 ovarian follicles were reached to the MII stage, but one of them was developed to parthenogenetic embryo as well despite a case of fusion from the nuclear transferred embryo. Embryos were collected in a surgical way on the 7th day after artificial insemination, numbers of average embryos collected were 2.5 and 3.0 in each 2 flower deer and elk does superovulated, respectively. The collected two embryos were transplanted to each 2 does synchronized. As a result, a head of fawn was produced from only one elk doe, where as a head of fawn were delivered from one out of 4 elk does artificial inseminated. Given these findings, we consider that more or less of problems might have occurred in vitro culture system of ovarian follicles in the production of nuclear transfered deer embryos. In addition, the greatest reason why both the aetificial insemination and embryo transfer failed was considered attributable to stress due to anesthesia and catching.

The objective of this study was to investigate the relationship between estrous expression, body condition score (BCS), blood urea nitrogen (BUN) and number of transferable embryos for the purpose of improving reproductive performance in blood of Hanwoo donors. Sixty, at random stages of the estrous cycle, received a CIDR. Four days later, the animals were superovulated with a total of 28AU FSH (Antorin, 2AU=1 ml) administered twice daily in constant doses over 4 days. On the 3th administration of FSH, CIDR was withdrawn and 25 mg PGF2α was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received 100 μg GnRH at the time of 1nd insemination. Embryos were recovered 7 or 8 days after the 1st insemination. The estrous inducement rate and estrous expression rate were significantly lower for cows with BCS below 2.25 than for cows with BCS above 2.25. There was 50.0% of rate of mounting in cows with BCS below 2.25 whereas the rate of mounting was markedly increased in cows with BCS above 2.25 (94.1% and 89.5% for BCS 2.25～2.75 and BCS above 2.75 cows, respectively). Cows with BCS ＜2.25, 2.25～2.75 and ≥2.75 had number of transferable embryos of 4.5±0.7, 5.9±1.8 and 5.6±2.3 respectively.

The objective of this study was to investigate the relationship between concentration of urea nitrogen, glucose, cholesterol and number of transferable embryos for the purpose of improving reproductive performance in blood of Hanwoo donors. Fifty five, at random stages of the estrous cycle, received a CIDR. Four days later, the animals were superovulated with a total of 28AU FSH (Antorin, 2AU=1 ml) administered twice daily in constant doses over 4 days. On the 3th administration of FSH, CIDR was withdrawn and 25 mg PGF2α was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received 100μg GnRH at the time of 1nd insemination. Embryos were recovered 7 or 8 days after the 1st insemination. Cows with BUN ＜10, 11～18 and ≥19 mg/dl had number of transferable embryos of 4.3±1.3, 5.8±1.8 and 4.7±2.1 respectively. The mean numbers of total ova from < 10 and 10≤ of corpora lutea(CL) was 8.9 and 14.3, respectively. The number of transferable embryos differed between < 10 and 10≤ CL was 4.8 and 5.6, respectively.

Previously, we reported that the osmolarity conditions in the satellite region were affected CpG DNA methylation status while Pre-1 sequence was not affected CpG DNA methylation in pNT blastocyst stage. This study was conducted to investigate the DNA methylation status of repeat sequences in pig nuclear transfer (pNT) embryos produced under different osmolarity culture conditions. Control group of pNT embryos was cultured in PZM-3 for six days. Other two treatment groups of pNT embryos were cultured in modified PZM-3 with 138 mM NaCl or 0.05 M sucrose (mPZM-3, 320 mOsmol) for two days, and then cultured in PZM-3 (270 mOsmol) for four days. The DNA methylation status of the Pre-1 sequences in blastocysts was characterized using a bisulfite-sequencing method. Intriguingly, in the present study, we found the unique DNA methylation at several non-CpG sequences at the Pre-1 sequences in all groups. The non-CpG methylation was hypermethylated in all three groups, including in vivo group (86.90% of PZM- 3; 83.87% of NaCl; 84.82% of sucrose; 90.94% of in vivo embryos). To determine whether certain non-CpG methylated sites were preferentially methylated, we also investigated the methylation degree of CpA, CpT and CpC. Excepting in vivo group, preference of methylation was CpT>CpC>CpA in all three groups investigated. These results indicate that DNA methylation of Pre-1 sequences was hypermethylated in CpG as well as non-CpG site, regardless modification of osmolarity in a culture media.

This study was conducted to investigate the survival rate of frozen-thawed spermatozoa in equine by glycerol concentration and freezing speed. Two stallions (1 Thoroughbred-13 year old and 1 Arab-7 year old) bred in Korea Racing authority was examined for 1 times in a couple of weeks. Semen was collected by condom method standing heated mare and were centrifuged 650 g for 15 min. and isolated the seminal plasma. Thick fraction of semen was diluted EDTA-Lactose-egg yolk diluents to 1:1 and contained in 0.5 ml straw as 6～14×107cells/ml. Final concentrations of glycerol were 3, 5 and 7% in cryopreseved diluents and added 4 times for 2 hours equilibration. For the freezing, equilibrated straws were located 3 or 5 cm above LN2 gas for 5 or 10 min. Survival rates of pre-frozen sperm were 65.0±13.2%, 68.3±10.4%, 66.7±11.5% and post-frozen were 53.3±23.1%, 45.0±15.0%, 50.0±18.0% in 3, 5, 7% glycerol concentration, respectively. There was no difference between glycerol concentrations. Survival rates of frozen-thawed sperm on freezing speed were 36.7±10.4%, 40.0±7.1%, 30.0±13.2% at 3 cm－5 min and 33.3±11.5%, 31.7± 2.9%, 21.7±10.4% at 3 cm－10 min in 3, 5, 7% glycerol concentration, respectively. Survival rates of frozen-thawed sperm on freezing speed were 43.3±15.3%, 32.0±17.9%, 22.3±15.7% at 5cm－5 min and were 47.5±15.0%, 43.3±12.6%, 48.3±15.3% at 5cm－10 min in 3, 5, 7% glycerol concentration, respectively. There were significantly different between groups (p<0.05). These results suggest that glycerol concentration did not affect cryopreservation of stallion semen within 3～7% but freezing speed affects. In our experiment, the best cryopreservation condition was at 5 cm above LN2 gas for 10 min for pre-freezing and 7% of glycerol concentration. These results lead to commercial AI with frozen-thawed stallion semen.

This study was performed to investigate the characteristics within ages and freezing tolerance of spermatozoa in Jindo Dog. Experimental animals were selected 12 herds within 1～8 year’s old and collected semen for 2 times in a week. Collected semen was evaluated whole volume and sperm number with CASA system (SIAS, Medical Supply, Korea). Then seminal plasma were separated and diluted with modified Tris-egg yolk extender and added 4, 6 and 8% glycerol for 4 times to final concentration and equilibrated for 1.5 hrs. Before and after freezing, equilibrated semen were evaluated the survival rates. Total volume of sperm at 1～2 year old group is as 5.2×108 cells/ ml largest and there were no significance among groups. The motility of 1～2 year old group is highest as 90.9% and there were significance among groups. Abnormal sperm showed similar among groups. The survival rate in terms of pre-freezing and post-freezing were decreased all levels of glycerol and reveled 87.0% to 64.5% in 4%, 87.5% to 51.9% in 6% and 73.4% to 29.7% in 8%, there were significant difference among the groups (p<0.05). These results suggest that the optimal sperm-freezing methods in Jindo Dog are utilized with modified Tris egg-yolk extender with 4% glycerol and were improve the reproductive activity by these methods.

The objective of this study was investigate the superovulation treatment and to relate concentrations of blood urea nitrogen(BUN) in Hanwoo donors. Thirty six, at random stages of the estrous cycle, received a CIDR. Four days later, the animals were superovulated with a total of 28AU FSH (Antorin, 2AU=1 ml) administered twice daily in constant doses over 4 days. On the 3th administration of FSH, CIDR was withdrawn and 25 mg PGF2α was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received 100 μg GnRH at the time of 1st insemination. Embryos were recovered 7 or 8 days after the 1st insemination. Cows with BUN ＜10, 11～18 and ≥19 mg/dl had return of estrus of 34.6, 30.5 and 30.4 days respectively. Return of estrus after superovulation treatment was not significantly lower for cows with blood urea nitrogen (BUN) above 10 mg/dl than for cows with BUN below 10 mg/dl. Cows with BUN ＜10, 11～18 and ≥19 mg/dl had number of transferable embryos of 3.2±1.2, 5.4±1.9 and 4.1±2.1 respectively.

The investigation was made about distribution and ecological characteristics of host plant for Phellinus linteus at habitats in Gangwon-Do. The habitats of P. linteus are the place where the fog is much generated and there is lots of the moisture. The flora of the vascular plants in P. linteus habitats were consisted of 76 taxa; 62 species, 10 varieties and 4 formas of 62 genera of 40 families. The plants of infiltration type were found 70% around P. linteus habitats. This results shows that the natural environments of P. linteus habitat is very stable condition. The categories of vegetation were classified into two types. The host plant for P. linteus appeared 61.6% from Populus tomentiglandulosa. The first type showed up above the sea about 600m and west exposure region. The second type was investigated around the facing north region of the steep slope-land.

A village grove is the one fostered and protected for a district's traditional life near the vicinity of a ruderal village. This research is done to grasp potential natural vegetation, to use a basis data needed for its management and preservation as well as restoration project by examining the vegetation and flora targeting a village grove of the southern district of Gyeonggi-do which has been seriously damaged subsequent to a rapidly progressing city development. According to the survey, there appeared an outgrowth flora of Pteridophyta consisting of 69 families, 136 genera, 20 varieties, 3 forms, 170 species-totalling to 193 taxa. Urbanization index was revealed to 4.55% and naturalization rate 6.74%. In life-cycle pattern, perennials were found to show the highest distribution rate; in infiltration-multiplication strategies, human wave tactics type was found to be the highest 51%, consisting of 98 species, and naturalization rate also was revealed to be 6.74%. The vegetation unit was divided into a total of 11 patterns, such as a community of Pinus densiflora community, Pinus densiflora-Pinus rigida community, Pinus densiflora-Castanea crenata community, Pinus rigida community, Pinus rigida-Castanea crenata community, Pinus rigida-Quercus acutissima community, Castanea crenata community, Castanea crenata-Quercus acutissima community, Quercus acutissima community, Quercus acutissima-Robinia pseudo-acacia community and Robinia pseudo-acacia community. Quercus acutissima community is of a community type dominated by Quercus acutissima, in place of Pinus densiflora community selected by natural succession.