Jeju pony, a natural monument no. 347 living in Jeju Island, Korea, has been conserved as a genetic resource and a racing pony. A total of 125 studies written about this breed have been published in various fields, primarily animal science (106), veterinary medicine (13), and others (6), from 1961 to 2018. Specifically, the majority of studies have been published in animal breeding and genetics (84), which are subcategories in the field of animal science. However, most of the research in breeding and genetics for Jeju pony were performed in the early 2000s, and studies using recently developed techniques are inferior to other breeds (thoroughbred etc.). Our current understanding of both the conservation and utilization of the breed is still incomplete. Thus, it is important to use recently developed technologies to improve management and breeding strategies for this pony breed. In this study, we review studies on Jeju ponies in the field of animal breeding and genetics and discuss problems that need to be addressed. Reviewed studies were divided into 6 categories: systematic classification, coat color, body measurement and growth, racing performance, behavior, and effective population size. Finally, we suggest ideas for future research projects that could potentially contribute to the Jeju pony industry.

Antioxidants have been added to cryoprotectant or in vitro culture medium for sperm to reduce the detrimental damage, such as reactive oxygen species. However, curcumin, an antioxidant, shows dual effect on the viability and progressive motility of bovine sperm exposed to hydrogen peroxide. Low concentration of curcumin increases sperm viability and progressive motility, whereas high concentration of curcumin reduces them. This study was performed to identify whether TREK-1 channel is related to low sperm viability and motility induced by high concentration of curcumin. Curcumin reduced TREK-1 channel activity in a dose-dependent manner. TREK-1 channel was expressed in sperm obtained from Korean native bull. Treatment with TREK-1 channel blockers, such as curcumin, fluoxetine, GdCl3, and spadin, significantly reduced sperm viability and motility (p < 0.05). However, TREK-1 channel activators showed different effect; linoleic acid showed an increase in sperm viability and motility, and wogonin did not affect them. These results show that TREK-1 channel is involved in the regulation of sperm viability and motility. In particular, high concentration of curcumin might reduce sperm viability and progressive motility of Korean native bull through blockage of TREK-1 channel.

Although cryopreservation of sperm is routinely used for clinical requirement, it has some problems, such as high generation of reactive oxygen species (ROS) and cold-shock. To reduce the detrimental damage in sperm, anti-oxidants were added to cryoprotectant for sperm. Curcumin is one of anti-oxidants, which are added in cryoprotectants. However, recent studies have demonstrated that curcumin decreases sperm viability and motility. This study was performed to identify the effect of curcumin on hydrogen peroxide (H2O2)-exposed bovine sperm, which were cryopreserved-thawed. In H2O2-exposed bovine sperm, reactive oxygen species (ROS) were significantly reduced by treatment with curcumin in a dose-dependent manner (p < 0.05). Among tested concentrations of curcumin (1 to 50 μM), 30 and 50 μM curcumin showed anti-oxidant effect on H2O2-induced ROS generation. On the other hand, combination of 30 or 50 μM curcumin with anti-oxidant H2O2 increased the percentage of apoptotic sperm compared to only H2O2 treatment. Sperm viability was also decreased in the combination of 30 or 50 μM curcumin with H2O2 as judged by FDA/PI staining. H2O2–induced decrease in sperm progressive motility was recovered by treatment with 1 μM curcumin. These results show that high concentration of curcumin has anti-oxidant effect, but it has also cytotoxic effect on bovine sperm. Sperm viability and motility might be more affected by cytotoxic signals of curcumin compared to antioxidant signals.

The occurrence of mastitis in diary cattle has been caused by genetic, physiological, managemental and environment factors accounted for the highest percentage of worldwide disease in dairy cattle. The purpose of this study was to analyze the occurrences and causative bacteria of subclinical mastitis in milking cows and also examine the distribution of bacteria in milk by isolating and identifying bacteria both in whole milk and quarter milk. 31.4% of the milking cows suffered subclinical mastitis, and 9.5% had it in terms of quarter milk. According to the results of analyzing bacteria in quarter milk of which somatic cell count (SCC) was over 500 thousand, 15 kinds of bacteria were isolated, and among them, Pantoea spp. formed the biggest part as 15.8%. From whole milk, 37 kinds of bacteria were identified, and among them, Klebsiella oxytoca showed the highest identification rate as 30.1%. According to the results of bacteria analyzed from the quarter milk of entire milking cows, 52 kinds of bacteria were identified. Among them, 17 kinds of Staphylococci were isolated, and CNS (Coagulase-Negative Staphylococci) formed a large part as 44.9%. The findings of this study showed that various kinds of bacteria were isolated from cows having subclinical mastitis; therefore, when managing specifications about milking or such, dairy farm will have to take proper action like performing sanitary control or counting somatic cells regularly in order to do their best for reducing mastitis.

Programmed cell death or apoptosis is associated with changes in K+ concentration in many cell types. Recent studies have demonstrated that two-pore domain K+ (K2P) channels are involved in mouse embryonic development and apoptotic volume decrease of mammalian cells. In cerebellar granule neurons that normally undergo apoptosis during the early developmental stage, TASK-1 and TASK-3, members of K2P channels, were found to be critical for cell death. This study was performed to identify the role of K+ channels in the H2O2-induced or cryo-induced cell death of mouse and bovine embryos. Mouse and bovine two-cell stage embryos (2-cells) exposed to H2O2 for 4 h suffered from apoptosis. The 2-cells showed positive TUNEL staining. Treatment with high concentration of KCl (25mM) inhibited H2O2-induced apoptosis of 2-cells by 19%. Cryo-induced death in bovine blastocysts showed positive TUNEL staining only in the cells near the plasma membrane. Cryoprotectant supplemented with 25 mM KCl reduced apoptosis slightly compared to cryoprotectant supplemented with 5 mM KCl. However, the combination of antioxidants (β-mercaptoethanol) with 25 mM KCl significantly decreased the rate of H2O2-induced and cryo-induced apoptosis compared to treatments with only antioxidants or 25 mM KCl. These results show that blockage of K+ channel efflux for a short-time reduces H2O2- and cryo-induced apoptosis in mouse and bovine embryos. Our findings suggest that apoptosis in mouse and bovine embryos might be controlled by modulation of K+ channels which are highly expressed in a given cell type.

The objective of this work was to analyze the concentrations of progesterone (P4) and estrogen (E2) hormones changed during estrus synchronization in dairy heifers. Estrus synchronization was carried out with CIDRⓇ (Controlled Intravaginal Drug Release) devices. Corpus luteum (CL) was classified into three grades based on its size and palpable characteristics. The concentrations of P4 and E2 were measured by enzyme-amplified chemiluminescence. Serum P4 concentration was markedly low at the estrus stage (36 hrs after removal of CIDR) compared to other stages, while E2 concentration was kept high during estrus stage. The serum P4 concentration was highest in the CL classified into gradeⅠ. These results indicate that P4 concentration could be used as a criteria for determining recipients for artificial insemination or embryo transfer in dairy cattle.

This study was performed to analyze the causative agents of disease occurred in Korean black goat. Bovine viral diarrhea (BVD) and infectious bovine rhinotracheitis (IBR) known as main causative agents of diarrhea and abortion in cattle were founded in Korean black goats. Escherichia coli and Clostridium perfringens are the main causes underlying diarrhea in Korean black goats as well as other animals. In addition, the orf virus was found as a causative agent of contagious ecthyma that shows frequent occurrence in Korean black goats. Leptospirosis was found in Korean black goats with low occurrence rate. However, unlike the reports from many other countries, we could not detect the antibodies for Johne’s disease and Neospora caninum in Korean black goats. These results are likely to contribute to improving the productivity of raising black goats as a field of livestock farming.

임신의 성립 및 유지에 중요한 자궁 내막과 호르몬의 변화는 생식기관에서 발현되는 K 통로의 발현을 변화시킬 수 있다. 본 연구는 한우의 임신 자궁 내막에서 K 통로의 발현 변화가 나타나는지 그리고 프로게스테론에 의해 그 발현량이 변화되는지를 확인하고자 수행하였다. 역전사중합효소 중합반응과 웨스턴블닷 분석을 통하여 임신한 한우의 자궁 내막에서 mRNA와 단백질의 발현 변화를 조사하였다. TREK-1을 제외한 K 통로의 mRNA 발현량이 임신 자궁 내막에서

The objective of this work was to determine the effect of corpus luteum (CL) grade on pregnancy rate after embryo transfer in Korean cattle and we found that CL development was linked to pregnancy rate. The in vivo derived blastocyst-stage embryos were transferred to 15 recipients synchronized in the estrus cycles. Based on size and palpable characteristics, CLs were categorized into three grade. The grade three CL is not to be identified by rectal palpation. The pregnancy rates tended to increase with the increase in CL size of recipients. In grade one, two, and three, the pregnancy rates were 62.5%, 50.0%, and 0%, respectively. This result suggests that pregnancy rates after embryo transfer might be affected by the CL status of recipients.

Oxygen consumption has been regarded as a useful indicator for assessment of mammalian embryo quality. This study was performed to investigate whether oxygen consumption reflects morphological grade of in vivo derived bovine blastocyst-stage embryos (blastocyst). The oxygen consumption of in vitro produced blastocyst was compared to its total cell number. In addition, pregnant rate was measured after transplantation of in vivo blastocysts with different oxygen consumption. The quality of blastocyst collected on day 7 after artificial insemination was categorized as grade I and II (G I and G II) based on microscopic observation of the morphology. Oxygen consumption of blastocyst was measured using a scanning electrochemical microscopy (SECM) and total cell number of in vitro blastocyst was enumerated by counting cells stained by propidium iodide. Pregnancy of recipient cow was confirmed with rectal palpation after 60 days of embryo transfer. The oxygen consumptions of G I blastocysts were significantly higher than those of G II blastocysts ( versus , p<0.05). Total cell numbers of in vitro blastocysts were 74.8, 90.7, and 110.2 in the oxygen consumption of below 10.0, 10.0~12.0, and over respectively. Total cell number was significantly increased in embryos with high oxygen consumption (p<0.05). Pregnant rate in recipient cow was 0, 50, and 85.7% in the transplantation of embryo with the oxygen consumption of below 10.0, 10.0~12.0, and over , respectively. These results suggest that measurement of oxygen consumption may help increase the pregnant rate of bovine embryos.

난포낭종은 소 번식 장애의 주요 원인 중의 하나이며, 다양한 유전자의 변화는 여러 세포와 조직 기능에 영향을 준다. 이러한 유전자 변화는 낭종성 난소에서도 나타날 수 있다. 이온 및 수송체와 관련된 유전자 변화가 한우의 난포낭종을 유발할 수 있을 것이라는 가설 하에 난포낭종성 난포에서 발현 변화를 보이는 유전자를 찾기 위하여 마이크로어레이 분석을 수행하였다. 마이크로어레이 분석 결과, 난포낭종성 난포에서 FGG와 LRP8이 증가하고, SLC44A4, S

Oxygen consumption has been regarded as a useful indicator for assessment of mammalian embryo quality. However, there was no standard criterion to measure the oxygen consumption of embryos. Here, we measured oxygen consumption of bovine embryos at various developmental stages was measured using a scanning electrochemical microscopy (SECM). We found that the oxygen consumption significantly increased in blastocyst-stage embryos compared to other stage embryos (from 2-cell-stage to morula-stage), indicating that oxygen consumption reflects the cell number ( versus , p<0.05). In the morula-stage embryos, the oxygen consumption of in vivo derived embryos was significantly higher than that of in vitro produced embryos ( versus , p<0.05). However, there was no significant difference in consumption of oxygen by in vivo and in vitro-derived bovine blastocyst-stage embryos (p>0.05). In the frozen-thawed blastocyst-stage embryos, live embryos showed significantly higher oxygen consumption than dead embryos ( versus , p<0.05). These results indicate that the measuring oxygen consumption by SECM can be used to evaluate bovine embryo quality.

Two-pore domain 칼륨() 통로는 흥분세포 및 비흥분세포의 안정막 전압을 일정하게 유지하는데 관여한다. 그러나 생식세포 및 생식기관에서 발현되는 통로의 분포영역 및 그 기능에 대해서는 연구자들에 의해 아직 정리되지 못하였다. 본 종설에서는 통로의 생식세포 및 생식기관에서 발현, 분포 및 생리학적 의의를 논하였다. 통로는 인간 영양막세포, 자궁근층, 태반혈관계, 자궁평활근조직, 태반융모조직 및 임신자궁조직에서 발현되어 임신에 있어서 관련성을 제

It is not easy for porcine embryos produced by in vitro systems to develop into blastocysts with high quality. To solve this problem, many researchers have developed novel culture methods. However, the formation of blastocysts with high quality is still low. In this study, we aimed to produce piglet following transfer of in vitro produced early embryos ( cell stage embryos) or morula and blastocyst. The cell stage embryos were transferred to five estrus-synchronized recipients (200 embryos per recipient). One of the five sows farrowed three piglets, which contain two live piglets and one dead piglet, 114 days after embryo transfer. However, two recipients transferred with morula and blastocysts did not farrow. Microsatellite analysis confirmed that the genomic DNA of two live piglets were not genetically identical to that of the recipient. These results indicate that it is possible to obtain piglets by transfer of early embryos produced by in vitro production (IVP) systems.

본 연구는 한우의 난포낭종 및 황체낭종에서 세포자멸사 관련 유전자의 발현 변화를 조사함으로써 난소낭종과 세포자 멸사간의 관계를 정리하고자 한다. 마이크로어레이 분석 결과, 난포낭종에서 PIK3R2와 AKT1가 유의하게 증가하였고, 황체낭종에서는 증가되는 세포자멸사 관련 DEGs, TNF-RAF2, PRLR, FOXL2, STK4 및 COL4A3와 감소하는 DEGs, INHA, CIDEB, BCL10 및 FASLG가 포함되었다. 정량적 역전사 중합 효소

The objective of this study is to investigate the changes in concentrations of leptin and insulin in serum of Korean cattle (Hanwoo) with reproductive disorders and to examine the relationship among leptin, insulin, and body condition score (BCS). The concentration of leptin in serum of pregnant Hanwoo showed insignificant difference from that in serum of Hanwoo with reproductive disorder, such as repeat breeding, follicular cyst, corpus luteum cyst, ovarian atrophy, and feeble estrus (p>0.05). However, the concentrations of leptin and insulin in serum were changed with different BCS value. In emaciated Hanwoo (BCS ), they were significantly decreased compared to BCS (p<0.05). The leptin showed different genotypes with different BCS value. In BCS , C/T genotype was expressed (83.3%) more than C/C (16.7%) or T/T (0%) genotype, whereas C/C genotype was expressed (62.5%) more than C/T (25.0%) or T/T (12.5%) genotype in BCS . The insulin concentration in follicular fluid obtained from ovary with follicular cyst which has follicles having diameter of was significantly higher (p<0.05) than those in normal follicle fluid which has follicles having diameter of . These results showed that concentration of leptin and insulin in serum were related to BCS value and follicular size and suggest that the changes in concentration of leptin and/or insulin in serum could be a potent biomarker for diagnosis of bovine reproductive disorder.

The objective of this study is to investigate the changes in concentrations of blood urea nitrogen (BUN) and sex steroid hormones, such as estrogen, progesterone, and testosterone in Korean cattle (Hanwoo) with reproductive disorders and to examine the relationship between BUN and body condition score (BCS) in Hanwoo. The concentration of BUN was 16.2 mg/dl, 17.8 mg/dl, 15.1 mg/dl, 17.9 mg/dl, and 28.3mg/dl in pregnancy, repeat breeding, follicular cyst, luteal cyst, and ovarian atrophy, respectively. In Hanwoo with BCS , and , the concentration of BUN was 15.8 mg/dl, 17.0 mg/dl, and 17.6 mg/dl, respectively. Fluoroimmunoassay showed that serum estrogen and progesterone levels were decreased in reproductive disorders Hanwoo, such as ovarian atrophy, endometritis, and weak estrus. The testosterone level was significantly decreased in Hanwoo with reproductive disorders compared to that in pregnant Hanwoo ( vs 0.13 ng/ml, p<0.05). The progesterone and estrogen concentrations in follicular fluid obtained from ovary with follicular cyst were significantly higher (p<0.05) than those in normal follicle fluid. These results show that there is no relationship between BUN and BCS in Hanwoo, and the concentration of sex steroid hormone in serum and follicular fluid are changed in reproductive disorders Hanwoo.

본 연구는 한우의 자궁내막염에서 발현 변화를 보이는 유전자를 마이크로어레이를 이용하여 조사하였다. 정상적인 자궁내막과 자궁내막염이 있는 자궁내막을 비교한 결과, 전체 확인된 4,560개의 유전자 중 2,026개의 유전자가 자궁내막염에서 증가하였고, 2,534개의 유전자가 감소하였다. 본 연구에서는 상위 조절되는 유전자 10개씩을 정리하였다. 자궁내막염에서 filamin A, pancreatic anionic trypsinogen, Rho GDP dissociation inhibitor alpha, collagen type VI alpha 1, butyrate response factor 2, aggrecanses-2, annexin 14, aminopeptidease A, orphan transporter v7-3 및 epithelial stromal interaction 1의 발현율이 26배 이상 증가하였다. MHC class II antigen, integrin-binding sialoprotein, uterine milk protein precursor, down-regulated in colon cancer 1, glycoprotein 330, dickkopf-1, cfh protein, Ca2+-dependent secretion activator, UL16 binding protein 3 및 proenkephalin은 25.5배 이상 감소하였다. 본 연구에서 얻어진 유전자 정보는 한우의 자궁내막염 진단에 필요한 유용한 생물지표로 사용되어질 수 있을 것으로 사료된다.

본 연구는 돼지 체외수정란 생산효율을 향상시켜 돼지의 품종개량, 형질전환 돼지생산 등과 멸실위험에 처해 있는 유전자원의 보존을 위한 기술로 활용하기 위해 미성숙 난포란의 적정 체외성숙 시간을 알아보고, 배양액의 종류 및 체외 배양시의 산소 농도에 따른 체외수정란의 생산 효율을 확인한 결과는 다음과 같다. 1. 돼지 미성숙 난포란의 체외성숙 시간별 제2감수분열중기(M II)까지 성숙된 비율이 체외성숙 38, 40, 42시간째에 각각 61.1%, 42.9%