The aim of the present study was to evaluate and estimate timing of artificial insemination (AI) in Hanwoo heifer (Korean native cattle) that is the most popular breed of beef cattle in Korea. To determine changes in body weight of heifers around AI, body weight were measured at different stages either before or after AI. We found that daily body weight gain was higher in the pregnant cows after AI. We also investigate correlation between body mass measured by shoulder height and body length, and conception rates, used (body length+ height)2 instead of height2 for body mass index (BMI), and found that relatively more BMI heifers (>55) showed higher conception rates. Finally, we estimated body weight by measuring should height (SH), heart girth (HG), and body length (BL); BW=3.93372*HG-2.90985*SH-0.021*BL. In addition, we observed that HG is most closely correlated with BW; y(BW) = 1.77355*x(HG), R² = 0.98881. In summary, we can determine the best timing of AI using body measurement and its application including BMI.

The HNF4α (hepatocyte nuclear factor 4, alpha) is a hepatic transcription factor related to the lipid metabolism and regulation of insulin secretion in humans. The current study about commercial broiler reported that the A543G single nucleotide polymorphism (SNP) within HNF4α gene has an effect on fat deposition and wing yield in the chicken. This study was performed to investigate the association between the SNP within HNF4α gene and growth trait and to verify the applicability as a molecular marker for the improving the performance in Korean native chickens (KNCs). A total of 764 KNCs was collected from the livestock farm of Gyeongnam National University of Science and Technology in Korea and genotyped by PCR-RFLP. The body weight measured at birth, 2, 4, 6, 8, 10, 12, 14, 15, 16, 18, 20, 24, 28, 32, 36, and 40 weeks of age for the association analysis between chicken growth and the SNP genotype. Statistical analysis of the SNP with phenotypic traits was performed using SAS program. The KNC strain was classified by the genotypes of the A543G SNP. The frequencies of three genotypes were 0.47 (AA), 0.43 (AG) and 0.10 (GG), respectively. The SNP of HNF4α has highly significant association (p<0.001) with all-round growth in KNCs. These results suggest that the A543G SNP within HNF4α gene could be a genetic marker for the breeding in Korean native chickens.

The recovery of epididymal sperm in animals is considered as one of the important tools to preserve high value or endangered species. However, there are no appropriate castrating indicators such as months of age in bull, sperm morphology, and motility, particularly in young Korean native bull (Hanwoo). Therefore, this study aimed to investigate sperm number, morphology, and motility of sperm in the epididymis tail of young Hanwoo bulls at 8 and 15 months of age. After castration, epididymal tails were collected and minced with blades to recover sperm. In experiments 1 and 2, sperm number, morphology, and motility were examined. Total number of sperm and percentage of normal sperm from bulls at 8 months of age was lower than that of bulls at 15 months of age after collection (P<0.05). Percentage of abnormal head, tail, proximal cytoplasmic droplet, dead and damaged acrosome of sperm from bulls at 8 months of age were higher than those of bulls at 15 months of age (P<0.05). In experiment 3, sperm motility from bulls at 8 and 15 months of age were examined before freezing and after thawing. Frozen-thawed sperm at 8 months of age showed low total motility and motile sperm with ≥ 25 μm/sec compared to those at 15 months of age and commercially-used sperm (P<0.05). In conclusion, sperm derived from the epididymal tail of bulls at 8 months of age showed high abnormal morphology and poor motility, which are not adequate for AI and IVF. On the other hand, sperm derived from the epididymal tail of bulls at 15 months of age showed high normal morphology and motility.

The KLF(Kruppel-like factors) are transcriptional regulators that including the C2H2 zinc-finger motif and regulation of cell growth, cell differentiation, and development. In this study, mRNA and total DNA was extracted from the meat around the backbone of 130 cattle that has economic traits score. The KLF11 gene was act on the center of the main pathway in associated with the development and growth of cells and the fat metabolism. Genetic polymorphism was detected by DNA sequencing. A total of four SNPs(G9047A, C9104G, G9131A, C9170T) were identified in exon 4 regions, statistical association analysis revealed that the G9131A polymorphism were significantly associated with marbling score. The real time quantitative PCR to investigated gene and miRNA expression patterns and identify the relation of economic trait in Korean Native Beef Cattle. Gene expression level linked to KLF11 genes was investigated by determining its association and variation with the economic traits in Korean Native Beef Cattle. The increment of KLF11 gene expresstion level is resulted in increasing marbling score(MS). We found that expression profile of KLF gene and mir-494 was contrast tendency because the lower expression ratio of gene was the higher marbling score rating was when we analyzed expression profile ofKLF gene and mir-494. Therefore, this result has useful in improvement of livestock in Korean cattle.

This study was conducted to determine grazing intensity of growing Korean native goats (Capra hircus coreanae) on mountainous pasture. It was carried out to obtain basic information for improvement of mountainous pasture management and establishing feeding system of Korean native goats. Castrated, male goats (n=10) with average initial body weight (BW) of 23.33±2.15kg and an average age of 4 months were used in this study. Grazing goats were supplemented by concentrates with 1.0% of BW. The crude protein content of forage was the highest in October (22.71±0.25%) and there were significantly differences (p<0.05) in monthly comparison. The forage productivity of pasture was the highest from May to June (1718.7±207.5~ 1672.0±422.8 kg/ha) but it was decreased in July (1356.0±103.8 kg/ha) because of drought and summer depression. Average daily gains (ADG) of goats were the highest in June (99.5±6.4 d/g). Grazing intensity was calculated by forage productivity and dry matter intake (DMI) and was the highest in May (65 head/ha). As shown in the results of this research, grazing intensity was suggested to average 39 head/ha from May to October. It is desirable that adequate grazing intensity was maintained by adjusting supplemental feed.

In experiment dealt with 240 Hanwoo (172 steers and 68 heifers) among the 456 cattle during growing and fattening period were used from 2004 to 2015. Growth period was divided into 6, 12, 18, and 24 months for steers and 6, 12, 18, and 43 months for heifers. The results showed that lying down, feeding, and drinking behavior increased according to the growth. In contrary, the time of locomotion behavior including standing and walking behavior were reduced. Aggressive behavior was observed to be mostly generated in the first 6-months. Thus the results showed that different growth period of Hanwoo steers can be used as management systems for breeding and disease management. It conclude that providing a comfortable living space is a useful management systems suppress stress to the minimum extent without giving unnecessary stress to the animals.

농장동물복지형 한우 사양관리를 통한 고품질의 쇠고기 생산을 목표로 세계적인 트랜드에 부합하는 축산선진국으로 나아가기 위하여 본 시험으로 우방내 사육공간의 넓이차이에 따른 한우의 사양성적, 행 동특성 및 혈액성상에 미치는 영향을 비교·분석해 보았다. 16개월령의 한우 54두(암소 미경산공태우 및 거세우 각각 27두)를 공시하여 성별에 따라 사육공간의 넓이차이를 주기 위해 4두(8m2), 3두 (10.67m2) 및 2두(16m2)로 처리하여 9개월간 각각 3반복으로 완전 임의배치 후 실시하였으며, 한우 사 양관리 프로그램에 따라 사료급여를 하였다. 데이터 수집방법으로 증체량, 사료요구율 및 혈액분석은 2 개월 간격으로 반복하여 측정하였으며, 행동패턴 수집은 복수개체 추적방법 및 선택적 행동관찰법으로 기상청에서 제공한 맑은 날을 선정하여 15일간 녹화 후 분석에 이용하였다. 본 시험의 결과로, 사양성 적(체중, 일당증체량 및 사료요구율)의 경우 미경산공태우와 거세우 각각 20개월령과 18개월령 이후부 터 2두와 3두 처리구에서 모두 유의적(p<0.05)으로 향상되었다. 행동특성으로는 미경산공태우의 2두 처 리구에서 행동시간으로 기립행동은 유의적(p<0.05)으로 낮고, 횡와 및 걷기행동은 유의적(p<0.05)으로 높았다. 행동빈도에서는 음수, 자기몸핥기, 긁기, 몸비비기, 투쟁행동에서 유의적(p<0.05)으로 적게 나 타났다. 거세우의 2두 및 3두 처리구에서는 미경산공태우와 유사한 경향을 나타냈으나 유의적(p<0.05) 으로 섭식시간은 증가하고, 다른소핥기 및 몸기대기의 빈도는 유의적(p<0.05)으로 적게 나타났다. 혈액 성상으로 미경산공태우와 거세우의 4두 처리구에서 적혈구가 유의적(p<0.05)으로 낮았고, 콜티졸은 유 의적(p<0.05)으로 높게 나타났다. 또한, 미경산공태우의 헤모글로빈과 거세우의 백혈구 수치에서는 모 두 2두 처리구에서 유의적(p<0.05)으로 각각 높고 낮은 것으로 분석되었다. 이상의 결과를 종합하면 사 양성적, 행동특성 및 혈액성상 등의 전체적인 내용을 토대로 우사의 여유 및 표준우사의 우방크기를 고 려할 때 한우의 사육공간에서 관행사육인 4두 처리구(두당 8m2) 보다 미경산공태우는 2두 처리구(두당 16m2), 거세우는 3두 처리구(두당 10.67m2)로 사육하는 것이 적절하다고 판단되며, 본 시험결과는 추후 복지형 한우의 사양관리를 위한 기초자료로 활용할 수 있을 것으로 판단된다.

본 연구에서는 내건성 식물 선발을 위한 최적 인자를 구명하고, 이들 내건성 식물들의 생장특성을 조 사하였다. 건조저항인자에 대한 나머지 건조저항일(RD), 엽면적(LD), 단위증산량(UTR), 상대함수량 (RWC), 상대수분손실량(RWL), 엽면적(LA), 기공수(SN) 및 기공면적(SA) 등 6개 인자들을 비교한 결과 상대수분손실량과 단위증산량이 건조저항일에 많은 영향을 주는 것으로 나타났다. PCA분석 결과 SA, LA, RD는 한그룹으로 RWC와 SN은 다른 한 그룹으로 구분되었고, UTR은 SA, LA와, RWL은 RWC와 SN과 음의 상관을 보였다. 상기 결과를 종합하여 느릅나무, 도깨비바늘, 뚝갈, 매듭풀, 새, 더위지기, 맑은대쑥, 독말풀, 긴담배풀, 소리쟁이, 비수리, 장구채, 개기장, 도깨비가지를 내건성 식물 종으로 선 발하였고, 이들에 대한 생장시험을 수행하였다. 절토사면지에서 내건성 식물의 줄기생장은 식물 종간에 약간의 차이를 보였는데, 줄기생장과 잎의 수는 느릅나무를 제외하고 폿트에서는 차이를 보이지 않았 다. 그러나 절토사면지에서 내건성 식물 뿌리 생장과 T/R율은 폿트생장과 큰 차이를 보였고, 특히 T/R 율은 폿트묘보다 월등히 낮았다. 이 결과로 보아 선발된 내건성 식물은 절토사면지와 같이 척박한 토양 에서도 잘 적응할 것으로 나타나 내건성 식물의 육종 등에 이용될 수 있을 것으로 판단된다.

The purpose of this study is to investigate university students’ perceptions on their English conversation classes taught by native English speakers. Its focus is on finding out how well the students understand and how actively they participate in class, what causes difficulty in their understanding or participation in class, and whether their class helps them in terms of affective aspects and English skills. A survey was conducted on a total of 465 university students in Korea, and the collected data were analyzed to compute basic descriptive and inferential statistics. Some of the important findings are 1) over 50% of the students understand their classes well; 2) a little over 30% actively participate in class; 3) about 30~50% of the students perceive their class help them affectively; and 4) about 50% of the students perceive their class help them improve their English skills in general. These results are discussed along with other findings related to the causes of the difficulties that the students experienced. Suggestions are provided on the basis of the results and their implications.

In this study, the texture, nucleotide-related compounds, and sensory characteristics of dry-aged beef, made from third quality grade Hanwoo beef (Korean native cattle), were investigated according to aging periods. Loin cuts obtained from three different Hanwoos were dry-aged under the specific conditions (controlled temperatures, humidity, and air flow) during 0-7 weeks. With increasing aging periods, textures were significantly decreased after 5 weeks (hardness: from 13,264±2,033 to 7,112±1,743 g; chewiness: from 4,107±1,467 to 2,334±780) and four sensory characteristics were significantly increased after 3 weeks (texture: from 2.2±1.0 to 6.2±1.1; flavor: from 3.9±0.7 to 6.2±1.5; whole preference: from 2.5±0.8 to 6.3±1.3; purchase intention: from 3.7±1.4 to 6.0±1.5) except for color (p<0.05). On the other hand, the concentrations of IMP which is related to the umami flavor of beef were significantly decreased with increasing aging periods (from 40.44±5.97 at 0-week to 7.44±2.43 μg/ mg at 7-week) (p<0.05). These results obtained in this study could provide an useful data base for the quality control of dry-aging.

This study aimed to investigate antioxidant activities from 11 forest plants, and determine their total phenolics, flavonoids and proantocyanidins contents. In addition, the antioxidant activities were correlated with antioxidant compounds. Among the samples, Cornus officinalis, Castanea crenata, Lindera erythrocarpa, Carpinus laxiflora and Pourthiaea villosa showed significantly higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50=21.12~28.93 μg/mL) and 2,2’-azino-bis(3-ethylbenzothia zoline-6-sulfonic acid) (ABTS) (IC50=28.18~52.55 μg/mL) radical scavenging ability with reducing power (IC50=59.91~93.64 μg/mL) than other plants; and C. crenata, L. erythrocarpa and Rubus coreanus showed strong nitric oxide (NO) inhibition activity (≥60%). In addition, L. erythrocarpa, C. laxiflora and P. villosa showed higher oxygen radical absorbance capacity (ORAC) values (≥1,100 μM TE/g sample) than other samples. High total phenolic contents were observed in C. crenata (429.11 mg GAE/g), L. erythrocarpa (437.11 mg GAE/g), C. laxiflora (408.67 mg GAE/g) and P. villosa (404.11 mg GAE/g). The DPPH and ABTS radical scavenging activity with reducing power were significantly correlated with total phenolic contents (R2=0.71~0.79), but total phenolic contents were not correlated with NO inhibition and ORAC (R2=0.35~0.43). Therefore, these results suggested that C. officinalis, C. crenata, L. erythrocarpa, C. laxiflora and P. villosa are potential natural antioxidative candidate ingredients.

이 연구의 목적은 성염색체 특이적 초위성체마커의 대립 유 전자 다양성과 빈도를 조사하여 한국 재래소 3품종의 (칡소, 한우 그리고 제주흑우) 유전적 근연관계 및 특징을 조사하여 우리 고유 유전자원으로서의 가치를 구명하고자 하였다. 한국 재래소 3품종은 30개의 초위성체 마커에서 선별된 4개의 초 위성체 마커(INRA30, TGLA325, UMN0905 및 UMN0929) 를 이용하여 식별하였다. 대립 유전자의 다양성, 대립 유전자 빈도, 이형접합도 그리고 다형 정보량(PIC)을 산출 하였다. 칡 소, 제주 흑우와 한우에 대한 관찰 이형접합도의 평균은 각각 0.541, 0.406 및 0.61이었고 PIC의 평균은 각각 0.542, 0.377 그리고 0.6이었다. 제주흑우의 경우 칡소나 한우에 비해 낮은 이형접합도와 PIC를 보여준다. 이들 4개의 초위성체 마커를 이용하여 칡소, 제주흑우 그리고 한우의 품종을 구별에 이용 할 수 있다. 이러한 결과들로 볼 때 한국 재래소 3품종은 가 축유전자원으로서 중요한 가치를 지니고 있으며 이들 품종의 보존, 관리 및 활용에 중요한 기초자료로 이용될 것으로 사료 된다.

The aim of this study was to investigate the effects of different rearing spaces on growth performances, behavioral traits, and blood parameters in Hanwoo (Korean Native Cattle) heifers and steers. The average daily gain and feed conversion ratio were measured to assess the growth performance. A total of 54 Hanwoo heifers and steers at 18 months old, were housed separately in groups of 2, 3 or 4 heads in a pen (32 m2) for nine months. In the case of the heifers, the growth performances were significantly (p<0.05) improved by increasing the 2 head group size with the exception of the 18 month old heifers. However, among the steers the growth performances were significantly enhanced (p<0.05) after 18 months of age, by increasing the 3 heads group size. In addition, the heifers in groups of 2 heads spent less time standing and more time lying down or walking, and also had a significantly (p<0.05) lower frequency of self-grooming, scratching, and fighting. These findings are similar to the results obtained for steers housed in 2 or 3 heads per group. The steers housed in 2, 3 heads groups spent more time feeding and consequently had a significantly (p<0.05) lower frequency of pair-wise grooming and Leaning. The heifers and steers housed in groups of 4 heads showed lowest red blood cell counts, but highest cortisol content with statistical significance at p<0.05. The heifers in groups of 2 heads had the highest hemoglobin concentrations (p<0.05). On the other hand, white blood cell count was found to be the lowest in groups of 2 steers with statistical significance at p<0.05. We conclude that a large rearing space improved growth performances, behavioral characteristics, and blood parameters in Hanwoo heifers and steers. In the future, this data could be used to improve the welfare of rearing Hanwoo cattle.

The post-hibernated queens of Korean native bumblebee, Bombus hypocrita saporoensis were collected in Jeong-Sun, Korea to investigate their ecological characteristics and reared under the laboratory conditions; 27℃, 65% R.H. and darkness. The average weight of collected queens was 0.87±0.14g and 0.8g class was most abundant (34.7%) among eight weight classes. The rates of colony initiation, colony foundation and progeny-queen production were 76.3%, 60.0% and 42.5%, respectively. The durations up to colony initiation and colony foundation were 12.0±6.7 days and 49.3±2.4 days, respectively. The duration up to first worker, male and queen emergence were 22.2±3.0 days, 63.4±6.5 days and 63.5±8.7 days, respectively. The number of progenies was 108.5±26.0 workers, 186.7±70.7 males and 39.1±30.3 queens. The longevity of colony founded queen was 90.2±19.9 days whereas that of non-colonized queen was 35.9±30.3 days. Copulation time was 29.5±9.6 min. The number of eggs per egg cell laid new queen was 9.3±2.3 grains. An egg shaped as banana and it’s size was 1.12±0.10 mm in a width, 3.54± 0.16 mm in a length and 2.26±0.34 mg in a weight.

Bovine papillomaviruses (BPVs) are DNA oncogenic viruses that belong to the Papillomavirus genus. The purposes of the present study were to histopathologically diagnose skin warts on Korean native cattle from Jeju Island and to detect the presence of BPVs from tissue samples of the skin warts, using the polymerase chain reaction (PCR) assay. The sites of 10 skin wart involvement were the head (40%: 10% were in both the head and neck), shoulder (30%), neck (20%), and tail (20%), including the perineum. All skin warts were confirmed as fibropapillomas, as characterized by the abundant proliferating fibrous tissue in the dermis and increased epithelial covering of variable thickness. According to the PCR analysis, five out of 10 (50%) cattle were positive for BPV-1, and six (60%) cattle were positive for BPV-2. Two cattle were positive for both BPV-1 and BPV-2. To the best of our knowledge, this is the first study of BPV-1 and BPV-2 infections of skin warts from Korean native cattle in Korea.

Calculating break-even price of calf production is closely associated with reproductive efficiency. To determine the price, we need data from reproduction records including number of claves weaned, number of cows exposed for breeding, and annual cash coast per cow, and average weaning or market weight of claves sold and retained. Unfortunately, the data were not available in Korea native cow (Hanwoo). To evaluate the performance and the price, we collected calving interval from about 60,000 cows for last 10 years and estimated reproductive performance. Calving interval was increased 4.3% and pregnancy rate was decreased about 1.4∼2.8% year-on-year. Increases in growth rates of number of cow and semen per calf supported the low reproductive performance. Finally, break-even price was calculated using estimated percent calf crop and demonstrated that growth rate of break-even price is larger than that of annual cash per cow, suggesting cow-calf profitability and financial efficiency in Korea native cow (Hanwoo) is getting worse.

The objective of this study was to monitor health conditions of genetically identical somatic cells cloned Korean white cattle, endangered indigenous cattle (EIC) and indigenous cattle (IC) by analysis of hematologic characteristics. Naturally ovulated oocytes and donor cells were used for somatic cell nuclear transfer (SCNT). Donor cells and enucleated oocytes were followed by electric fusion, chemical activation and surgical embryo transfer into the oviducts of surrogate females. Two recipients became pregnant; two maintained pregnancy to term, and one live cattle were delivered by caesarean section. The cloned Korean white cattle were genetically identical to the nuclear donor cattle. As a result, the mean values of RBC and platelet of cloned cattle and white cattle were significantly decreased by age (P<0.05). The mean values of RBC, HCT, MCV and MCHC between cloned cattle and IC of the same age (1∼2 years) showed the statistical significance (P<0.05). Also, in the WBC of Korean white cattle, the estimated values were decreased according to the age from 12.0×103/μl under 1 year to 11.0×103/μl over 1 years respectively. Although clone-cattle had lower numbers of RBC than reference range, the most of RBC and WBC related heamatologic results of cloned cattle were not different when compared to reference range. This study suggests that cloned Korean white cattle derived from SCNT did not have remarkable health problems, at least in the growth pattern and hematological parameters. In addition, this study provides a valuable resource for further investigations of the preservation of rare genetic stocks underlying traits of interest in cattle.

These studies were conducted to establish the practical Hanwoo (Korean native cattle) improvement system through the combining of embryo transfer technology and confirming individual Hanwoo oocyte culture system and to investigate that correlation of Hanwoo carcass classification (intramuscular marbling) and oocyte donor for blastocyst production in vitro. In case of Hanwoo, the carcass meat quality grades were divided to grade 1⁺⁺, 1⁺, 1, 2, and 3 depends on fat distribution of longest muscle cross-sectional surface. As results, the numbers of follicular oocytes collected from individual fundamentally-registered Hanwoo yielded 1⁺⁺, 1⁺, 1, 2 and 3 meat quality were 9.5, 9.4, 8.5, 8.8 and 8.8 per ovary, respectively. The numbers of retrieval oocyte from follicles were significantly higher in the cattle yield 1⁺⁺, 1⁺ meat quality than in the cattle yield 1, 2 and 3 meat quality (p<0.05). The rates of blastocyst formation were 18.2, 21.3, 29.4, 30.9, and 31.5% in the cattle yield 1⁺⁺, 1⁺, 1, 2 and 3 meat quality of after in vitro maturation, respectively. It was significantly lower in the cattle yield 1⁺⁺ and 1⁺ meat quality than in the cattle yield 1, 2 and 3 meat quality (p<0.05). In order to evaluate embryos quality, TUNNEL assay was conducted for each meat quality grade using blastocyst stage embryo on day 8. The results showed that apoptosis cell number was higher tendency in the cattle yield 1⁺⁺and 1⁺ meat quality (81 and 79, respectively) than in the cattle yield 1, 2 and 3 meat quality (51, 48 and 50, respectively) but there was no statistical significance in each group. After embryo transfer, the conception rate of recipient was 53.5 (23 out of 43), 52.1 (38 out of 73) and 58.0% (58 out of 100) in the meat quality of 1, 1+ and 1++, respectively. These results showed that the conception rate was significantly higher in the cattle yield 1 meat quality than in the cattle yield 1⁺⁺, 1⁺ , 2, and 3 meat quality (p<0.05). In summary, these results indicate that the application of confirming Hanwoo individual oocyte culture system and embryo transfer technology can make good use of the genetic resources conservation and improvement of Hanwoo. Relevance of the meat quality grade and reproductive ability of carcasses of Hanwoo will be considered to be one of the effective means for the associated research with obesity and reproduction.