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이종이식을 포함하여 바이오 의료산업 분야에 형질전환 돼지는 모델 동물로서 광범위 하게 활용되고 있다. 목표 유전자를 과발현하는 형질전환 돼지를 개발하기 위하여 바이 러스 유래 염기서열이 포함된 cytomegalovirus enhancer chicken beta-actin (CAG) 프로 모터가 가장 많이 활용되고 있다. 그런데, 바이러스 유래의 프로모터는 세대가 지남에 따 라 그 활성능이 감소된다고 알려져 있어, 발현 효율을 세대에 관계없이 지속시킬 수 있 는 프로모터의 개발이 필요하다. 이에 본 연구에서는 효율적으로 목표 유전자를 발현하 는 형질전환 돼지 개발에 활용하기 위한 돼지 유래의 프로모터를 개발하고자 실시하였 다. 이를 위하여 바이러스 유래의 CMV, CAG 프로모터, 사람 유래 elogation factor 1 alpha (EF1α) 프로모터, 돼지 유래 porcine elongation factor 1 alpha (pEf1α) 및 actin (pActb) 영역을 pGL3 vector에 클로닝한 뒤 돼지 신장 상피세포(pk15), 돼지 혈관 내피세 포(pAECs), 돼지 귀 섬유아세포(pEFs)에서 luciferase 분석을 통해 CAG 프로모터에 대한 상대 활성을 비교 분석하였다. 그 결과 pEf1α 프로모터가 CAG 프로모터에 비해 높은 발 현 조절 효율을 보여주었고, 특히 pEFs에서는 유의적으로 높았다(p<0.001). 이종이식시 발생하는 세포성 거부반응 억제 유전자로 알려진 Human Leukocyte Antigen-E (HLA-E) cDNA를 pEf1α와 CAG 프로모터에 각각 연결한 발현 카세트를 제작한 후 pEFs에 도입하 여 발현 효율이 장기간 세포 배양에도 유지되는 지를 분석하였다. 항생제 선별 개시(0일) 후 14, 18, 22, 26, 30일 동안 배양한 각각의 세포에서 RNA와 단백질을 추출하여 정량 -PCR 및 Western blot 방법으로 HLA-E 발현 수준을 분석하였다. 그 결과 pEf1α 프로모 터는 HLA-E의 지속적 발현 유지를 유도하는 반면에 CAG 프로모터에 의한 HLA-E의 발 현은 18일차부터 급격히 감소하는 것을 확인하였다. 14일과 30일째 flow cytometry 분석 을 실시한 결과, HLA-E 발현 세포 수는 CAG에서 12.7%에서 7.4%로 감소한 반면에, pEf1α에서는 25%에서 28.9%로 유지되고 있음을 확인하였다. 이러한 결과로 pEf1α 프로 모터는 돼지 세포에서 목표 유전자의 발현을 장기간 배양에도 효율적으로 조절하여, 과 발현 형질전환 돼지 개발에 유용하게 활용될 수 있을 것으로 기대된다.

Understanding the sophisticated imprinting pattern is the first challenge for deciphering the molecular mechanism of an imprinted gene. However, the determination of imprinted genes, and their methylation status in pigs, remains inefficient at present. Herein, for the first time, we have made an attempt to illustrate the complex imprinting pattern of porcine GNAS complex locus by an efficient strategy using RNA-seq analysis of parthenogenetic fetuses containing no paternal allele, but two maternal alleles. RNA-seq results showed that Nespas, Gnasxl, and Exon 1A genes expressed at extremely lower levels (p<0.05) in parthenogenetic fetuses compared to the normally fertilized fetuses, suggest these three genes are paternally-expressed. Whereas, the expression levels of Gnas were similar in both groups, suggesting biallelic expression of Gnas. The parental-specific expression of these genes was further confirmed by quantitative real-time PCR. Bisulfite sequencing revealed that the maternally derived Nespas promoter was methylated, but the paternal chromosome was not methylated. Our finding provided full-scale imprinting information on porcine GNAS locus for the first time. Furthermore, our study is useful for identify novel imprinted genes, confirm the previously known imprinted genes, and determine imprinting pattern efficiently.

Maternal (oocyte-derived) follistatin has a positive functional role in control of time to first cleavage of bovine embryos, subsequent development to the blastocyst stage and in blastocyst cell allocation to the trophectoderm lineage. Follistatin binds to and inhibits activity of members of the transforming growth factor superfamily, whose signals are mediated intracellularly primarily through activation of receptor associated SMADs (rSMADs) including SMAD-2/3 (activin, TGF-b) and SMAD-1/5/8 (BMPs). We hypothesized that the positive actions of follistatin on early embryogenesis may be mediated via inhibition of ligand induced rSMAD signaling. To address this hypothesis, we determined the temporal expression and effects on bovine early embryogenesis of siRNA mediated knockdown of SMAD-4. SMAD-4 is a common component of above signaling pathways which complexes with respective rSMADs. SMAD-4 mRNA in early embryos is maternally derived and its abundance is temporally regulated during early embryogenesis. SMAD-4 siRNA injection at the zygote stage also significantly reduced proportion of embryos cleaving early and proportion of embryos developing to the 8~16 cell and blastocyst stages. Furthermore, SMAD-4 siRNA injection at the zygote stage had no effect on abundance of mRNA for the trophectoderm cell marker CDX2 and inner cell mass cell marker Nanog in bovine blastocysts. Results suggest a functional role for maternal (oocyte-derived) SMAD-4 in bovine early embryonic development. However, the phenotype of SMAD-4 depleted embryos is distinct from that observed in response to follistatin ablation or replacement.

Successful cryopreservation of bovine oocytes is a very important technology for research and commercial applications. However, the survival and development rate of vitrified- thawed oocytes is lower then non-vitrified oocytes. This study was confirmed the effect of cryoprotectant solutions treated with Hydroxypropyl cellulose (HPC) supplementation for oocyte vitrification in bovine. For vitrification, bovine MII oocytes were pretreated with EG10 (added 0, 10, 50 and 100 μg/mL HPC) for 5 min, exposed to EG30 (added 0, 10, 50 and 100 μg/mL HPC) for 30 sec, and then directly plunged into LN2. Thawing was taken by 4-step procedures [1 M sucrose and 10% FBS added D-PBS (SFD) → 0.5 M SFD → 0.25 M SFD → 0.125 M SFD ] for 1 min, respectively. After thawing, cumulus cells were partially removed by treatment with 0.05% hyaluronidaseand mechanical pipetting. Oocytes were washed with TL-HEPES, incubated in a droplet of previous cultured IVM medium for 1 h to recover. As shown results, in vitro survival rate of bovine vitrified-thawed MII oocyte was significantly higher in 50 (85.5%) and 100 μg/mL (80.2%) groups than 0 (71.2%) and 10 μg/mL (71.3%) groups. After in vitro fertilization, the cleavage rate was no significantly different between treatment groups. Therefore, these results were shown HPC treatment have a positive effect on the survival of vitrified-thawed bovine oocytes.

Female fertility is a highly regulated process involving the synchronized activities of multiple tissues. The underlying genomic regulation of the tissue synchronization is poorly understood. To understand this better we investigated the transcriptomes of the porcine ovary, endometrium, and oviduct at days 0, 3, 6, 9, 12, 15, or 18 of the oestrous cycle. We analysed the transcriptome profiles of the individual tissues and focus on the bridging genes shared by two or more tissues. The three tissue-networks were connected forming a triangular shape. We identified 65 bridging genes with a high level of connectivity to all other genes in the network. The expression levels showed negative correlations between the ovary and the other two tissues, and low correlations between endometrium and oviduct. The main functional annotations involved biosynthesis of steroid hormones, cell-to-cell adhesion, and cell apoptosis, suggesting that regulation of steroid hormone synthesis and tissue viability are major regulatory mechanisms.

The endemic species of sika deer in Northeast Asia is endangered animals in South Korea. In the 1970s, some subspecies (C.n.taiouanus and C.n.yesoensis) were introduced from other countries for restoration, and were not the endemic species (C.n.hortulorum) of Northeast Asia. However, there has not been a sufficient study about endemic and reintroduced sika deer. The purpose of this study was to identify the genetic diversity and relationship of South Korean sika deer compared to those in other countries at Northeast Asia. Total 153 DNA samples (69 South Korean, 38 Chinese and 29 North Korean samples of captive bred, and 17 Russian of wild) were used in the analysis. The number of alleles per locus varied from 2~14 with a mean of 6. The expected heterozygosity and observed heterozygosity values were 0.3863 and 0.2740, respectively. The mean polymorphism information content value was 0.3528, ranging from 0.026~0.826. The genetic distance analysis showed genetic difference between South Korean and other populations, and Russian and North Korean populations were genetically similar. The maximum value of ΔK was observed when K was set to 2. When K=2, the genetic structure analysis revealed hybridization among four populations. Based on the information from structure results, we distinguished individuals with dominant genetic composition of a particular subspecies (>0.90), and the result showed relatively ‘pure’ individuals in South Korean population formed a distinct cluster that contradict other countries. As a result, all the sika deer populations in the four countries were genetically vulnerable. In addition, it is confirmed that relatively ‘pure’ individuals in South Korea were showed genetically different characteristics compared to other countries. However, the rate of hybridization was high in all populations of four countries, and it was also difficult to grasp the hybridization with other deer subspecies or other species. Moreover, STRUCTURE analysis results depending on the number and type of markers used for analysis. Therefore, additional samples and markers need to be acquired and analyzed.

TNF receptor associated factor 4 (Traf4) is a member of the TNF receptor associated factor (TRAF) family, a family of scaffold proteins. TRAF proteins connect IL-1R/Toll and TNF receptors with signaling factors that lead to the activation of NF-κB and mitogen-activated protein kinases. However, the biological function of Traf4 is little known in preimplantation embryo development. We first examined the transcript levels of Traf4 from early cleaving to blastocyst staged embryos. We found that the transcription level of Traf4 increased from the 4-cell stage onwards and Traf4 was localized to the apical region of the outer cells. To elucidate the role of Traf4, we employed RNA interference using siRNA injection to the one-cell zygote. We observed arrested embryos between morula and blastocyst, and detected paracellular permeability sealing using FITC-dextran uptake assay in Traf4 KD. In summary, our findings strongly suggest that Traf4 plays important roles in blastocyst formation during mouse preimplantation development.

Understanding preimplantation embryo development is important because of early embryonic mortality during pre-and post-implantation in assisted reproductive technology (ART). Thus, assessment of in vitro produced embryo prior to ET is the most final in vitro step to monior embryo development and select the best embryo. However, diagnosis of early embryo developmental potential in ART is still limited. Tight junction (TJ) is a crtitical component for blastocyst formation including a fluid-filled cavity, but the functional role was not extensively elucidated after cavitation. To elucidated the importance, we employed loss of function studies and chemical treatment for disruption on interaction between TJs. In the knock-down (KD) or inhibition treated embryos (IHB), half of embryos were arrested between morula to blastocyst transition period. Moreover, among KD and IHB blastocyst transferred to uterus of recipients, half of them failed to maintain pregnancies after 2nd trimester. Collectively, TJ complex and its integrity provide insights into implication of translational research for prediction and selection of developmental competency in human ART.

Predator stress can exert detrimental effects on female mammals, leading to be morphological or behavioral and ultimately come at the cost of survival, growth, body condition, or reproduction. Although there have many studies about predator stress on reproductive output of rodents, however, few talk about the effect of visual or auditory stress to the pregnant female. In this study, we investigated the possible effect of predator stress, visual or visual plus auditory, on the reproduction performance of female mice after non-surgical embryo transfer. The reproductive performance has been assessed for pregnancy rate, implantation rate, gestation length, live pups rate and neonatal birth weight. Moreover, female serum cortisol and progesterone level were measured by using Electrochemiluminescence Immunoassay. Surprisingly, the exposure to predator stress did not lead to a significant change in pregnancy rates of the tested mice. However, the stressed mice showed significant (p<0.05) decrease in implantation rate compared to the control group. Similarly, the live pups rate and neonatal birth weight were significantly lower in the group exposed to cat stress than in the control group. Furthermore, mice exposed to visual plus auditory stress showed significant reduction in gestation length compared to the control mice. Our data showed that predator stress in form of visual plus auditory combined stimuli significantly increased the serum cortisol level. On the other hand, progesterone level did not show any significant variation among different experimental groups. Taken together, our findings imply that predator stress adversely affect the reproductive efficiency of pregnant mice by decreasing the implantation rate, live birth rates, neonatal birth weight and prolong the gestation length. These data will help in identify the reasons behind the effects of prenatal predator stress on reproductive failure.

최근 들어 암소의 수태율과 관련된 수많은 생리활성물질들에 대한 연구결과이 보고되 어지고 있다. 이들 중 저농도의 resveratrol 처리에 따른 효과 관련 연구결과들에서 임신 호르몬인 progesterone (P4), estradiol-17β (E2) 등의 생리적인 변화에 따라 sirtuin (SIRT1)의 발현에 유의적인 차이가 나타난다고 보고하고 있다. 따라서 본 연구목적은 한 우 암소 자궁 내 resveratrol을 주입하여 암소의 수태율을 관찰하고 이를 바탕으로 P4, E2, SIRT1의 변화양상을 조사하고자 한다. 공시축은 생후 14개월령 미경산 암소 20두를 대상으로 체중, 십자부고, 흉위, BCS 등 을 측정한 후 대조군 5두, 0.5, 1.0, 2.0 μM resveratrol 처리군 각 5두씩 설정하여 주입하 였다. Resveratrol 주입에 대한 수태율 효과를 정확하게 분석하기 위해서 전체 실험축군 을 배란동기화 처리하였고 10일째 일괄 인공수정 하였다. Resveratrol은 7일째 자궁 내 두당 20 mL 주입하였다. 배란동기화로 예상되는 주요 발정일은 9일째이며, 9일째 발정이 확인된 개체는 0.5 μM Resveratrol 주입군에서 100%로 가장 높게 나타났으며, 대조군은 40%, 1.0, 2.0 μM Resveratrol 주입군에서는 20%로 각각 확인되었다. 임신감정은 수정 후 40일 경과 후 초음파장비를 통해 수행하였으며 그 결과 발정확인률과 유사한 경향치 를 보이며 0.5 μM Resveratrol 주입군이 60%, 대조군은 40%, 1.0, 2.0 μM Resveratrol 주입군은 20%로 나타났다. 따라서 선행된 in vitro 수준의 연구결과와 동일하게 in vivo 수준에서도 저농도의 Resveratrol이 암소 수태율에 긍정적인 영향을 미친다는 것을 확인했으며, 추후 사전에 확보한 혈액으로부터 serum을 추출하여 P4, E2 등의 주요 호르몬 수치변화와 SIRT1의 발현여부를 분석하여 resveratrol이 어떠한 상호작용을 통하여 oocyte maturation과 embryonic development에 관여하는지 추가로 검증할 예정이다. 본 연구결과는 농가에서 쉽 고 간편하게 저비용으로 수태율을 향상시킬 수 있는 기술이기 때문에 한우 사육농가의 수익향상에 기여할 수 있다고 기대된다.

The development of methodological strategies that allow for the prediction of the fetal sex in cattle still remains a zoo-technical challenge. So far, different methods have been implemented to direct the breeding management in dairy cattle, giving producers an advantage in decision-making regarding the activity of planning and monetary gains. The objective of this study was to evaluate the use of next generation sequencing of fetal DNA in the maternal plasma of pregnant cattle in order to determine the sex of the fetus. The whole blood samples were collected from the five Holstein cows at 20-week of pregnancy. The serum plasma was harvested and the cell free DNA (cfDNA) was isolated in order to construct whole genome DNA library. The resulting DNA libraries were then paired-end sequenced (2×101 bp) with Illumina’s HiSeq 2500 instrument. The high quality, clean reads were mapped to the Bovine reference UMD 3.1 of X and Y chromosome separately, resulting an average depth and coverage of 3.54 and 86.2%. Our results revealed that four dairy cattle with male fetuses and 1 with a female fetus. Furthermore, it was concluded that fetal cells in maternal plasma can be used to predict the sex of the fetus in cattle. The detection of fetal DNA sequences is a reality and could reduce the risk of invasive techniques for certain fetal disorders in the near future.

우리나라에서 정액을 수입하는 미국이나 캐나다의 씨수소와 국내산 씨수소들 간에 비 교가 불가능하였다. 그러나 우리나라에서 2011년부터 참여하고 있는 국제 유전능력 평가 (인터불, interbull) 결과(EBV, PTA)를 활용하고 국내 씨수소 선발에 사용하는 KTPI 등의 선발지수를 수정하면 인터불 평가에 참여하는 모든 국가에서 생산한 씨수소들의 유전능 력 상호비교가 가능하다. 따라서 본 연구에서는 기존의 KTPI 선발지수를 변형한 새로운 KTPI 선발지수를 소개하고 기존의 지수들과의 상관관계를 분석하여 순위 변화 여부를 확 인하였다. 기존의 KTPI에 포함된 유지방량, 유단백량, 체형종합점수 외에 유방지수(UDC) 와 지제지수(FLC)에서 중간 최적 형질의 육종가 값을 변형하여 원 형질값 1~9점에서 5 점이 가장 높은 실숫값을 가지도록 절댓값 함수로 변환하고, 인터불 평가에 포함되지 않 는 뒷유방너비(유방지수 구성 형질) 심사 형질을 제외한 후 구성 형질값들의 상대적 가중 치를 비율적으로 조정하여 새로운 KTPI 지수를 구성하였다. 결과, 지제지수(FLC)는 중간 최적 형질 변환 전후 상관계수가 0.95였다. 유방지수(UDC)의 경우, 중간최적형질을 변환 전후 상관계수는 0.94였으며, 변환과 더불어 뒷유방너비를 제외한 전후 상관계수는 0.93 이었다. 그러나 KTPI로 종합한 지수에서는 중간최적형질 변환과 뒷유방너비 제외와 무관 하게 전후 상관계수가 1.00이었다. 결론적으로 전체적인 종합지수은 수정에 따른 변화가 거의 없었으나, 유방지수와 지제지수에 대해서는 중간최적형질에 대한 변환으로 인해 보 다 바람직한 선발 기준으로 이용할 수 있다.

본 연구는 우리나라 Holstein 암소의 번식형질에 대한 유전모수를 추정함으로써 암소개 량의 기초자료를 제공하고자 실시하였다. 자료는 농협중앙회 젖소개량사업소 검정자료 중 2009년부터 2013년까지 분만한 Holstein 경산우(2, 3, 4산차) 144,739두의 211,899개 의 분만기록을 이용하였으며, (사)한국종축개량협회에 등록된 252,170두의 혈통자료를 분 석에 이용하였다. 유전모수 추정을 위해 WOMBAT package을 이용하였다. 분만 후 첫 수정까지의 일수(CTFS), 임신기간(GL), 분만 후 56일 비발정율(NRR), 수정횟수(NS), 첫 수정부터 수태까지의 일수(FSTC), 공태일(DO) 그리고 분만간격(CI)의 유전력은 각각 0.064, 0.060, 0.005, 0.014, 0.012, 0.021, 그리고 0.021로 추정되었다. 각 형질들 간의 유전상관의 범위는 −0.910에서 0.995로 나타났다. NRR과 NS, NRR과 FSTC 사이의 유전 상관은 부(−)의 상관을 보였고, DO와 CI는 매우 강한 양(+)의 상관관계를 보였으며, CTFS와 FSTC는 DO와 CI 간에 0.479에서 0.862로 나타났다. CTFS와 FSTC간에는 낮은 유전 상관을 보였는데, 이는 각 형질에 영향하는 유전자들이 독립적인 관계에 의한 것으로 생 각된다.

The objectives of this study were to determine the effect of administration of exogenous hCG 5 days after artificial insemination (AI) on serum progesterone concentration and conception rate in dairy cattle. In this experiment 5 days after AI the cows were alternately assigned randomly to treatment group (n=67) received an injection of 1,500 IU hCG (Chorulon) and control group (n=61), received no treatment. On day 5, 10, 15 and 20 blood samples from 8 of cows (4 in each group) were obtained to measure serum progesterone concentration. Cows that were detected in estrous after days 18~24 were reinseminated and recorded as no pregnant (open) to the prior AI. The uteri of cows not observed in estrous were palpated per rectum 60 days after insemination to determine pregnancy status. And pregnancy was diagnosed by ultrasonic examination. Pregnancy proportion in treatment and control groups were 52.5 and 36.1%, respectively. The results demonstrated that there was no significant differences between two groups (p=0.0568). Mean serum progesterone concentrations did not differ between treatment and control groups on day 5 (0.377 versus 0.375 ng/mL). On day 20 serum progesterone concentrations were greater in the treatment group compared with control group (3.085 versus 2.010 ng/mL). In conclusion, 1,500 IU of hCG 5days after insemination did improve pregnancy rate in dairy cattle, moreover the fact that serum progesterone concentration were higher in treatment group.

Endometritis is inflammation of the endometrium. Endometritis by breeding is major cause of infertility. The incidence of bacterial uterine infections has been reported to be 25~60% in mares. Mares show acute inflammatory response by semen after mating, which is charaterized by the influx of neutrophils, which are important in the physiological defense mechanism. The normal uterine inflammatory response in mare disappears within 48 hours after mating, but if inflammation persists, this is expressed as persistent post breeding endometritis (PPBE). Chronic endometritis is caused by bacteria and although the condition may have stemmed from PPBE. The diagnosis of endometritis is used three methods (ultrasonography, cytological and bacteriological examination, histology). This study was conducted in non-pregant mares(Jeju cross breed and Jeju horses) raised at Subtrophical Livestock Research Institute between 2016 and 2017. The non-pregnant mares with endometritis was diagnosed by ultrasonography, cytological and bacteriological examination used EQUIVET uterine culture swab (KRUUSE, Denmark). The rate of non-pregnancy was 9.16% (11/120) and the percentage diagnosed with endometritis of non-pregnancy mares was 18.18% (2/11).

소에 있어서 영양적인 불균형은 축군간의 다양한 질환의 발생과 더불어 번식 현상에 다변적인 요인으로 작용을 한다. 한우 농가의 번식우는 사양관리에 따른 영양 대사물질 불균형 등의 요인으로 번식효율이 저하됨으로 이에 대한 원인물질 탐색을 통해 농가 현 장에 적용 가능한 번식효율 향상기술 개발이 필요하다. 본 연구에서는 한우의 혈중 주요 영양 대사물질의 변화와 번식효율과의 상관관계 구명으로 번식 효율개선에 대한 조사를 위해서 본 연구를 수행하였다. 본 연구에서는 한우 74두를 실험에 공시하였으며 혈액 내 주요물질 분석을 위해서 대사판정검사(Metabolic Profile Test, MPT) 검사기법 적용으로 혈액성분 분석기기인 7020 automatic Analyzer, HITAHI(JAPAN)에서 분석을 실시하였다. 대사물질분석을 위해서 혈액 샘플채취는 오전 사료급여 3시간 후에 경정맥에서 채취하였 다. 분석한 영양대사물질은 Glucose (mg/dL), Cholesterol (mg/mL) BUN (mg/dL) AST (U/L) ALT (U/l), Nonesterified Fatty Acids (NEFA, uEq/L) 6종류에 대해서 분석을 실시하 였다. 암소의 사료급여는 배합사료(TDN 68%, CP 14%)와 건초를 급여하였다. 혈액채취 후 혈청을 분리하여 혈액대사물질 분석기기인 주요결과로서 임신우와 비임신에 있어서 주요 성분 분석 결과로서 Glucose는 68.39±18.98 vs. 71.21±19.40 Cholesterol 수치는 68.39±18.74 vs. 71.21±51.72 BUN은 16.60±3.08 vs. 25.78±7.72 AST는 125.1±28.96 vs. 130.4±28.67 ALT는 39.15±10.17 vs, 40.09±10.59, 마지막으로 NEFA 수치는 110.42±36.35 vs. 187.31±117.06로 나타났다. 번식장애와 연관이 있는 것으로서 혈중요소태질소(BUN) 의 증가는 농후사료의 과잉급여에 의하여 장애가 발생하는 것으로 알려져 있으나, 본 연 구의 결과에서 임신우와 비임신우에서 BUN과 NEFA의 농도에서 유의적인 차이를 보이 지 않았다. NEFA 농도는 번식우의 현재 영양균형 상태를 예측할 수 있는 지표로써, 에너 지 부족으로 인한 체지방 분해시 NEFA 함량이 증가하는 것으로 알려져 있다. 본 연구의 결과에서 임신우 179.82±108.93보다 비임신우에서 NEFA 값이 187.31±117.06로 다소 높 은 결과를 보여 한우에서 NEFA의 농도가 임신에 직접적인 영향을 미치는지에 대한 조사 와 분석이 더 필요할 것으로 사료된다.

본 연구는 국내 저지종 젖소를 도입하기 위하여 저지종 젖소 수정란을 구입하여 이식 한 성적에 대한 결과이다. 수정란이식은 2014년~2015년 46두를 이식하여 15두 분만한 성적만을 우선적으로 정리하였다. 발정동기화처리를 하여 발정발현 후 7일에 수정란이식 을 하였는데, 32.6%의 분만율을 보였으며, 259일 만에 조기분만으로 사산한 개체 1두를 제외하고 14두로 분석을 실시하였다. 암수의 비율은 9두가 암컷(64.3%)이고, 5두가 수컷 (35.7%)의 성비를 보였으며, 12두는 자연분만(85.7%)하였고, 2두는 수의사의 조력이 필요 한 분만(14.3%)이었다. 주간(09:00∼18:00)에 분만한 개체는 3두(21.4%), 야간(18:00∼익일 09:00)에 분만한 개체는 11두(78.6%)였다. 출생 시 몸무게는 27.29±4.5 kg이었으며, 임신 기간은 300일이 넘은 특이한 경우를 제외하고 분석한 결과, 275.7±4.7일이었다(발정발현 후 수정란이식까지 기간 7일에 이식부터 분만일까지 일자를 더한 값이다). 성별에 따른 몸무게, 임신기간을 비교하였는데 태어난 암컷의 체중은 26.6±4.2 kg이고, 수컷의 체중은 28.6±5.2 kg로 유의적 차이는 없었으며, 임신기간도 300일이 넘은 특이한 경우를 제외한 13두로 분석한 결과 암컷의 임신기간은 273.9±3.8일이고, 수컷의 임신기간은 279.8±4.3 일로 역시 유의한 차이는 없었다. 정확한 저지종의 번식관련 지표를 얻기 위해서는 좀 더 많은 수정란이식 데이터와 인공수정 데이터를 활용하여 추가분석이 필요하다.

본 연구는 돼지 정자의 성 분리 후 X, Y 정자에서 발현되는 단백질 차이를 분석하였 다. 정액은 국립축산과학원 양돈과에서 개량용으로 사육중인 듀록 수컷으로부터 채취하 였으며, 성 분리에 사용하기 전에 희석 액에 액상 처리하여 분리에 적용되었다. 정자의 성 분리 방법으로는 마그네틱 비드(magnetic bead)를 이용한 방법을 이용하였으며, 일반 적으로 포유류의 Y-정자는 양성전자를 갖고 있으므로 Y-정자를 마이크로 비드로 결합시 키고, 마이크로 비드를 자력을 이용해서 제거하는 방법을 사용했다. 정자 분리에 이용된 자력은 5,000∼7,000 가우스의 자석이 사용되었고, 정자의 부착력을 고려했을 때 직사각 형의 자석이 가장 효율적인 것으로 알려져 있음. 염화칼슘(0.05∼3 g/증류수 100 mL)이 포함된 정자 희석액(플라보노이드 당 포함)을 이용하여 전하의 경쟁을 유도하였고 정자의 분리 이동 속도와 결합도의 차이를 크게 함으로서 마그네틱 비드가 Y-정자에 특이적으로 결합하게 하였다. 분리한 X와 Y 정자는 two-dimensional (2D) polyacrylamide gel electrophoresis( PAGE) 방법을 이용하여 X와 Y 정자에 존재하는 단백질 발현 패턴을 분석하였 다. X와 Y 정자의 Image analysis 결과, pH가 낮은 산성 쪽에서 단백질 spot이 나타나고 있었으며 차후 LC-MS/MS 분석을 통해 단백질 동정을 예정하고 있다.

본 연구는 한우 번식우의 수정란 이식 시, 최근 개발되어 보급된 심부주입기의 수태율 증진 효과를 검증하고자 수행되었다. 대조군에 사용된 주입기는 현재까지 사용된 일반적 인 주입기(ET syringe, IMV)이며 실험군에 사용된 심부주입기는 2가지 형태의 주입기 (Telescopic syringe, IMV / ET gun, FHK)를 사용하였다. 수정란 이식 수태율 분석에 이 루어진 수정란이식은 2015년부터 2018년 5월까지 이루어진 결과를 이용하였으며 체외수 정란은 신선란과 동결란을 모두 사용하였다. 체외수정란의 생산은 도축장에서 도축된 암 소의 난소를 실험실로 운반하여 실험에 이용하였으며 체외성숙은 FSH 0.5 ug/mL, LH 5 ug/mL, 0.125% BSA가 첨가된 TCM199 배양액에서 22시간 동안 38.5℃, 5% CO2의 조건 에서 배양되어 이루어졌다. 체외수정은 선별된 성숙난자를 1×106 /mL의 정자농도를 사용 하여 체외수정을 유도하였으며 mTALP 배양액에서 21시간동안 38.5℃, 5% CO2의 조건 에서 배양되어 이루어졌다. 발달배양은 mSOFaa 배양액을 사용하여 38.5℃, 5% CO2, 5% O2의 조건에서 최대 9일간 이루어졌다. 수정란 이식은 7, 8일차의 체외수정란을 발 정발견 후 7, 8일째의 수란우에 이식하였다. 실험결과, 대조군, 심부 IMV 및 심부 FHK에 서 이식 후 수태율이 32.9±7.2b, 52.3±7.3a 및 20.8±4.7c로 조사되었으며 유의적으로 심부 FHK를 사용한 결과가 높게 관찰되었다(p<0.05). 체외수정란의 7일차, 8일차 구분에 따른 이식 후 수태율은 대조군, 심부 IMV, 심부 FHK에서 각 31.1±4.4 및 33.0±1.2, 52.5±5.7 및 52.1±1.3, 19.7±7.0 및 21.7±6.7로 확인되었으나 유의적인 차이는 발견되지 않았다(p< 0.05). 신선란과 동결란의 비교결과는 심부 IMV 처리군은 동결란의 이식결과가 부족하고 심부 FHK 처리군은 신선란의 이식결과가 부족하여 분석하지 못하였다. 결론적으로 본 연구는 심부주입기의 수태율 증진효과를 검증하고자 수행되었으며, 조사결과 ET gun 심 부주입기(FHK)가 유의적으로 증가된 수태율을 보여주었으며 Telescopic 심부주입기(IMV) 는 오히려 일반적인 형태의 주입기보다 감소된 수태율을 보여주었다. 이러한 결과와 본 연구자의 경험을 바탕으로 ET gun이 시술과정에서의 편리함과 수태율 증진에 효과가 있 다고 판단이 되지만 기기를 다루는 시술자의 숙련도에 의한 영향이 큰 점을 고려해야만 할 것이다. Telescpic 심부주입기(IMV)는 수정란 주입이 2단계로 작동하는 조작의 불편함 이 있으며 수정란이식 시술에 3가지의 1회성 소모품을 매번 장착과 제거해야 하는 번거 로움이 있으며 소모품의 비용 또한 값비싸 현장에서 사용하기에 일반적인 형태의 주입기 와 ET gun에 비하여 적합하지 않다고 판단된다.

본 연구는 사양관리 변경에 따른 혈중 주요성분 분석과 수태율과의 상관관계를 분석하고 자 수행되었다. 연구자가 관리하고 있는 횡성 관내의 1 농가를 대상으로 한우 암소 사양관 리 변화와 인공수정 수태율을 조사하면서 얻은 자료를 동일기간 내 번식우의 혈액으로터 분석한 혈중 MPT 결과와 비교분석하였다. 분석에 이용된 농가는 연구자가 5년 이상 인공 수정 업무와 사양관리 컨설팅을 수행하고 있는 농가로 최근 3년간 평균 이상의 인공수정 수태율을 나타내었지만 2017년 중반기 사양관리 형태의 변경으로 인한 급격한 인공수정 수태율 저하를 겪은 농가이다. 조사기간은 2017년 1월부터 2017년 11월까지이며 최근 3년 간 동일한 사양관리 형태를 유지하였던 2017년 5월까지의 기간 중 2016년부터 2017년 5 월까지의 조사결과를 대조군(67두)으로 사용하였으며, 사양관리 형태를 변경하였던 2017년 6월부터 2017년 11월까지의 결과를 실험군(25두)으로 사용하였다. 조사항목으로 수태율 관 련 인자는 평균 인공수정횟수, 평균 공태기간, 평균 발정주기, 인공수정 수태율 자료를 조 사하였고 혈중 MPT 분석은 AST, GGT, Glucose, Cholesterol, BUN, NEFA 항목을 조사하 였으며 급여되는 사료의 섭취량 또한 조사하였다. 실험결과, 사양관리는 대조군 농후사료 2～3 kg+건초 무제한+사일리지 2～3 kg/일, 실험군 농후사료 3 kg+오차드글라스 3 kg+혼 합건초 3 kg/일의 형태로 이루어졌다. 대조군과 실험군의 혈중 MPT 분석결과 NEFA 160.9±12 및 75.3±39 uEq/L, Glucose 60.1±8.2 및 89.4±10.7 mg/dL, Cholesterol 151.6± 21.1 및 101.9±21.2 mg/dL, BUN 12.8±3.5 및 10.0±6.2 mg/dL, AST 69.6±24.0 및 86.2±12.5 U/L, GGT 19.6±8.0 및 17.7±7.1 U/L로 확인되었다. 또한 건물, TDN 및 단백질 섭취량은 건물 6.87 및 8.05 kg, TDN 3.83 및 5.59 kg, 단백질 0.67 및 0.9 kg으로 조사되 었다. 인공수정 수태율 조사결과 대조군과 실험군에서 87.5±7.9 및 75.1±8.4로 조사되었으 며 수태율 관련인자는 평균인공수정횟수 1.2±0.5 및 2.5±0.4, 평균공태기간(일) 71±8.4 및 90.3±6.5, 평균발정주기(일) 21.4±0.5 및 22.5±0.6으로 조사되었다. 결론적으로 사양관리 형 태의 변경으로 인한 수태율 저하의 원인을 탐색하고자 본 연구가 수행되었으며 사료섭취에 따른 혈중 MPT 분석결과, NEFA의 농도에서 큰 변화가 관찰되었다. 본 연구에서 분석한 농가의 사양관리 형태 변화는 건초의 급여방법이 바뀐 것이 주요한 점으로써, 양질의 조사 료 공급원을 다양하게 유지하여 사양관리의 효율을 높이고자 현장의 여러 농가에서 최근 적용되고 있는 방법이다. 하지만 조사료의 선택과 급여량은 검증된 방법으로 고려되어야 한다. 본 연구결과는 실험두수가 부족하므로 추가적으로 다양한 농가 사양관리 형태의 조 건에서 동일한 실험결과와의 비교분석이 필요하다고 생각된다.

A artificial insemination (AI) has been used in Uganda for over 60 years, but a small population of the total herd has been bred using this method and pregnancy rates among dairy farms is still low. This study was conducted to optimize the Ovsynch method for improving the productivity of dairy farms through AI services in Uganda. In total, 160 cows from 18 dairy farms were selected for timed-AI. Synchronization was performed according to Ovsynch protocol with low GnRH (0.15 mg) followed by AI using frozen semen from Korean Holstein (0.5 mL straws). The pregnancy rate in low GnRH group was compared with the previously reported results using normal GnRH (0.25 mg). The overall pregnancy rate in normal group was 28.2% (22 of 78), whereas that in low GnRH was 49.4% (79 of 160) (p<0.01). The previous report implied that low pregnancy rate in normal GnRH was caused by a high occurrence of abnormal estrus (54.5%, 30 of 55). Thus reducing the GnRH during Ovsynch could reduce a occurrence of abnormal estrus. Taken together, these results suggested that use of low GnRH during AI services could improve the productivity of dairy farms in Uganda.

말 산업 육성 정책의 성장 척도를 가늠하는 말 사육두수는 2015년 대비 786두(3.0%) 증가한 27,116두로 2015년에 이어 지속적인 성장 추세에 있는 것으로 조사되었다. 그 중 승용 10,766두(39.7%), 경주용 7,732두(28.5%), 번식용 4,494두(16.6%) 등으로 승용마의 사육두수가 점차 증가 하고 있다는 것을 알 수 있다. 말은 계절번식을 하는 동물로써 말 의 비발정주기는 주로 겨울철로 알려져 있으나(Daels PF and Hughes JP, 1993; England GCW, 1996) 아직까지 말의 발정주기 분석에 대한 연구는 미흡한 실정이고, 암말 의 번식양상은 다른 종(species)들과 차이가 있으며 가장 낮은 번식 효율성을 갖고 있다 (Ginther, 1992). 암말의 발정주기는 개체마다 큰 차이를 보이고 있으며, 아직까지 정확한 원인 분석은 이루어지지 않은 실정이다. 본 연구의 공시축은 25두이며, 자궁경 검사는 자 연종부 한 말을 대상으로 질경 기구를 이용하여 임신여부를 확인하였다. 정상적인 난소 주기와 비정상적인 난소주기의 분석을 위해 난소주기형을 4가지 유형으로 분류 정의하였 으며, 난소주기가 진행이 되면 배란된 날에 난소주기가 재개된 것으로 간주하였다. 정상 적인 발정주기를 보이는 개체는 약 21일 주기로 호르몬의 변화를 보였으며, 비정상적인 발정주기를 보이는 개체에서는 40일 정도까지 발정이 지연되는 지연발정, 조기발정, 무발 정 등의 양상을 보였다. 총 21두의 공시마 중 13두(61.9%)만이 정상적인 난소주기를 보 였으며, 공시마 8두(38.1%)는 난소주기가 지연되는 것을 확인할 수 있었다. 난소주기 지 연을 보인 공시마 중 2두(9.5%)는 황체기가 계속 이어지는 난소주기 지연 Ⅰ형, 1두(4.8%) 는 배란이 지연되는 난소주기 재개지연 Ⅱ형, 5두(23.8%)는 난소주기가 길어지는 난소주 기의 재개지연 Ⅲ형이었다. 암말의 배란을 확인하기 위한 초음파검사 결과 우세난포 (40~50mm 이상) 관찰 후 6시간 이내에 11두에서 배란이 일어났으며 9시간 이내에 2두, 24시간 까지는 총 21두(100%)에서 배란을 확인하였다. 정상적으로 계절번식을 하는 개체 에서는 약 150일 가량 발정이 멈추는 것을 확인할 수 있었다. 10월에 3두(16.7%), 11월 에 5두(27.8%), 12월에 5두(27.8%)가 발정이 정지되었으며, 나머지 5두(27.8%)에서는 겨 울철에도 발정이 지속되는 것을 확인할 수 있었다. 발정이 정지된 개체는 이듬해 3월까 지 발정이 정지되어 있었으며, 비번식 계절에도 27.8%는 발정이 지속되었다. 18두 중 4 월에 11두(61.1%), 5월에 2두(11.1%)의 발정이 재귀되었다.

Sex-sorted sperm is now widely used in cattle breeding to enhance industrial competitiveness and achieve high female fertility. We bought a "Whole-mom" from the Nuri Science Co., Ltd company. The objective of this study was to evaluate the pregnancy rates and calves sexing proportion of male and female calves produced using Artificial insemination (AI), both performed using sexed and conventional sperm. The study was carried out spring to autumn season on 150 Hanwoo bred on a farm. In all superovulated donors, inseminations were initiated 12 hours after the onset of standing estrus. In a experiment, to take a sexed semen was mixed with "Whole mom" and conventional semen in a water bath at 37℃ for 20 minutes. The sexed and nonsexed semen was deposited in the body of the uterus. After collection, embryo morphology was assessed under a stereomicroscope. Embryos were transferred to the uterine horn ipsilateral to the CL. The conception rates were 73.3% (45/33) sexed semen and 48.8% (90/44) conventional semen. The sex ratio for sexed-semen inseminations was 70% (21/30) females for singleton births within a 279.2 to 282.1 day gestation interval. The sex ratio for unsorted semen was 56.8% (25/44) females for births. The use of X-sorted sperm, already widely employed for AI in dairy cattle has the potential to alter the structure of the industry by increasing the replacement heifer supply, creating opportunities for using a proportion of the dairy herd for producing beef animals, and improving the rate of genetic selection.

As an one of multifunctional cytokine, transforming growth factor-β (TGF-β) induces various signaling pathway in cells via bind to their receptor. This action of TGF-β plays a crucial role in regulation of uterine environment for successful pregnancy in mammalians. Plasminogen activators system (PAs) is one of important physiological system for reproductive events such as oocyte maturation, acrosome reaction, fertilization, and uterine remodeling. It is consist of two-types of PAs (urokinase-type, uPA; tissue-type, tPA), uPA-specific receptor (uPAR), and type-1 PA inhibitor (PAI-1). In various type of cells, activity of these system was regulated by gonadotropin, cytokines, and hormones. Although both of TGF-β and PAs system play important role in uterine environment, relationship between TGF-β and PAs system was not fully understood. Therefore, this study was conducted to investigate regulation of PAs activity and mRNA expression by TGF-β in porcine uterine epithelial cells (pUECs). pUECs were isolated from uterine horn and cultured until 50% confluence. Then, cells were starved in serum-free medium for 24 hours and subsequently medium supplemented with TGF-β supplemented medium (0, 0.1, 10, 50, and 100 ng/mL) for 24 hours. The expression level of mRNA was analyzed using real-time PCR and PA activity assay was used for measurement of PA activity in supernatant. In results, PA activity was significantly decreased in TGF- β 10, 50, and 100 ng/mL treared group compared with control group (p<0.05). On the other hand, TGF-β did not affect to expression levels of uPA, tPA, uPAR and PAI-1 mRNA. In present study, although expression of uPA, tPA, uPAR, and PAI-1 mRNA were not influenced by TGF-β treatment, relative PA activity was reduced according to TGF-β concentration increased. Therefore, these results suggested that TGF-β regulate translation process for control the PA activity in porcine uetrine cells.

This study investigated change of protein trafficking-related coatomer subunit gamma- 2 (COPG2) using proteomics analysis during estrous cycle in porcine endometrium. The endometrium tissues were collected from porcine uterus, were classified according to ovary morphology before or after ovulation. The COPG2 protein was found by two dimensional electrophoresis and MALDI-TOF/MS-MS, and COPG2 protein expression and location were observed using western blotting and immunofluorescence in proliferation and secretion phase endometrium tissues. Porcine endometrial epithelial cells (PEECs) were isolated from endometrium, and influence of progesterone (P4) on COPG2 protein change was observed using western blotting, flow cytometry and immunocytochemistry in PEECs. In result, eighteen protein spots were changed between proliferation and secretion phase endometrium, and molecular functional analysis demonstrated that one of theses, COPG2, was involved in protein trafficking between endoplasmic reticulum and Golgi apparatus. Additionally, the COPG2 was increased in tissue and PEECs from secretion phase compared to proliferation phase. The COPG2 protein was significantly increased by 40 ng/mL P4 treatment group compared to 0 and 10 ng/mL treatment groups P4 in PEECs. These results may provide understanding of protein trafficking in endomerium during estrous cycle, and will be used in basic study data for relation of P4 and protein trafficking in female reproductive tracts.

Matrix metalloproteinases (MMPs) comprise a family of zinc-dependent proteinases. Proteins of the MMPs family are involved in the breakdown of extracellular matrix in normal physiological processes, such as embryonic development. Successful implantation is closely linked to the expression of MMPs which greatly influences ability of an embryo to degrade the basement membrane of the uterine epithelium, mainly composed of type IV collagen, and invade the uterine stroma. The purpose of this study was to determine the MMP-2 & -9, also known as type IV collagenase, concentrations in mouse uterine fluid during implantation window, investigate the roles of MMP-2 & -9 on mouse trophoblastic cells invasion in vitro and study the effect of MMP-2 & -9 cotransfer with mouse embryos on reproductive performances. Protein level was detected by Elisa kit and invasiveness was assessed by an invasion assay. Optimal concentrations of MMP-2 and -9 was co-transferred to 2.5 dpc recipients using the non-surgical embryo transfer. Our results showed that MMP-2 & -9 protein levels in mouse uterine fluid were significantly increased at 2.5 dpc. Moreover, in vitro treatment significantly promoted both spreading and invasion of mouse trophoblastic cells as compared with the non-treated. Embryo transfer results showed that MMP-9 cotransfer enhanced mouse implantation and pregnancy rate compared with the control and MMP-2 cotransfered groups, however, that was not significant. Taken together, our findings imply that MMP-9 cotransfer with embryos can regulate embryo invasion during preimplantation, which may have serious consequence on embryo implantation and can be applied in other mammals so far as human being.

Estrogen is essential for reproductive processes such as maturation of ovarian follicles, embryo implantation, placentation, lactation, parturition, sexual differentiation, and sexual behavior in females. Generally estrogen binds to nuclear receptors, estrogen receptor alpha (ERα) and beta (ERβ). Recently, novel estrogen receptor, G protein- coupled estrogen receptor 1 (GPER1), has been identified and shown to be expressed in the plasma membrane. However, the expression and regulation of GPER1 has not been determined in the female reproductive system in pigs. Thus, this study determined the expression of GPER1 in the endometrium during the estrous cycle and pregnancy in pigs. We obtained endometrial tissues from gilts on day (D) 0, D3, D6, D9, D12, D15 and D18 of the estrous cycle and on D12, D15, D30, D60, D90 and D114 of pregnancy, and chorioallantoic tissues on D30, D60, D90 and D114 of pregnancy. GPER1 mRNA was expressed in the endometrium during the estrous cycle and pregnancy in pigs. During the estrous cycle, GPER1 expression was higher in diestrus and proestrus than in estrus and metestrus. During pregnancy, GPER1 mRNA was high during the preimplantation period and low during mid- to late pregnancy. Expression of GPER1 was significantly higher on D15 of the estrous cycle than D15 of pregnancy. RT-PCR analysis showed that GPER1 mRNA was not detectable in conceptus on D12 and D15 of pregnancy. In chorioallantoic tissues, GPER1 mRNA increased toward term pregnancy. Endometrial explant culture study showed that the expression of GPER1 mRNA was down-regulated by increasing doses of progesterone but not affected by estradiol. In situ hybridization analysis showed that GPER1 mRNA was localized to luminal epithelial cells in the endometrium on D15 of estrous cycle. These results indicate that GPER1 mRNA is expressed in the endometrium during the estrous cycle and pregnancy in a stage- and pregnancy status-dependent manner, suggesting that GPER1 may play an important role in mediating estrogen actions of the maternal-fetal interface in pigs. Further analysis of signaling pathway and function of GPER1 in the reproductive system is needed.

Caspases are a family of protease enzymes that play an essential role in apoptosis. Caspases can be subdivided to two groups. One is initiator caspases which include caspase 8 (CASP8), caspase 9 (CASP9) and caspase 10 (CASP10), and the other is executioner caspases which include caspase 3 (CASP3), caspase 6 (CASP6) and caspase 7 (CASP7). Once activated by death signaling proteins, initiator caspases cleave and activate downstream executioner caspases, which in turn execute apoptosis by cleaving targeted critical cellular proteins. In many studies, the caspase family is involved in cell proliferation and apoptosis and the expression of caspases is regulated by steroid hormones in the endometrium during the estrous cycle and pregnancy in mammals. However, the expression and function of caspases have not been determined in the porcine endometrium. Thus, to initiate the study on the role of caspases in the endometrium, we characterized the expression of caspases in the endometrium during the estrous cycle and pregnancy in pigs. We obtained endometrial tissue samples from glits on day (D) 12 and D15 of the estrous cycle and from D12, D15, D30, D60, D90 and D114 of pregnancy. Real-time RT-PCR analysis showed that the expression of CASP3, CASP6, CASP7, CASP8, CASP9 and CASP10 mRNAs was detected in the endometrium during the estrous cycle and pregnancy. Especially, levels of CASP3 mRNA were higher on D12 of pregnancy than the estrous cycle. To investigate the effects of steroid hormones, estrogen and progesterone, on expression of caspase, endometrial tissue explants from immature pigs were treated with steroid hormones. Increasing doses of progesterone, CASP7 mRNA increased but, decreased CASP8 and CASP10 mRNAs. In addition, increasing doses of IL1B upregulated the expression of CASP3 mRNA in the endometrium. Furthermore, immunohistochemistry analysis showed that CASP3 protein was localized to the luminal and glandular epithelial cells in the endometrium during the estrous cycle and pregnancy. These results indicate that caspases are expressed in the endometrium during the estrous cycle and pregnancy in a stage-depedent manner, and the expression of some caspase in the endometrium is regulated by steroid hormone or cytokine. Further analysis of localization and functions of caspase families at endometrium are needed.

Atypical chemokine receptors (ACKRs) are chemokine receptors with seven transmembrane domains that fail to initiate classical signaling pathways after ligand binding. ACKRs comprises four receptors, ACKR1, ACKR2, ACKR3, and ACKR4, and are mainly expressed by non-leukocyte cell types, such as epithelial cells, lymphatic and vascular endothelial cells. ACKRs function as crucial regulatory components in a wide range of developmental, physiological and pathological events by controlling chemokine availability and function. However, expression and regulation of ACKR genes in the endometrium during the estrous cycle and pregnancy are not fully understood in pigs. Thus, this study determined expression of ACKR1, ACKR2, ACKR3, and ACKR4 in the porcine endometrium during the estrous cycle and pregnancy, and conceptus and chorioallantoic tissues during pregnancy. Real-time RT-PCR analysis showed levels of ACKR1, ACKR2, ACKR3, and ACKR4 mRNAs in the uterine endometrium during the estrous cycle changed with the highest abundance in diestrus or proestrus phases. Levels of ACKR3 mRNA were higher on Day 12 of estrous cycle than Day 12 of pregnancy, while expression of ACKR2 and ACKR4 mRNAs showed higher levels on Day 15 of pregnancy than Day 15 of the estrous cycle. In situ hybridization analysis showed that ACKR3 mRNA was localized specifically to luminal and glandular epithelial cells during the estrous cycle and early pregnancy. Conceptus and chorioallantoic tissues during pregnancy also expressed ACKR mRNA, but not ACKR4 mRNA. To investigate the effects of steroid hormones on the expression of ACKR mRNA, endometrial tissue explants were cultured in the presence of steroid hormones, estradiol and progesterone. The levels of ACKR2 and ACKR4 mRNAs were increased by progesterone. These results showed that ACKR genes regulated by progesterone are expressed in endometrium during estrous cycle and pregnancy, suggesting that ACKRs may play a key role in regulating chemokine action in the endometrium during the estrous cycle and pregnancy.

Sex hormones including progesterons, androgens, and estrogens are influential in differentiation of ovarian tissues and competence of fertility. These steroid hormones derived from cholesterol are required for cumulus-oocyte complexes (COCs) during oocyte maturation. COCs is a total functional and active entity playing a central role in oocyte. Lipid metabolism in the mammalian COCs is controlled by environmental factors. The intracellular cholesterol contents go through remarkable changes. It plays an important part of oocyte developmental competence. However, heat stress affects steroid hormone by decreasing progesterone, estrogen concentrations, and resumption of meiosis in COCs maturation. Reduction of the hormone and meiotic resumption might lead to the decline of ovarian function, follicle maturation, and subsequent embryogenesis. In the same vein, heat stress also influence on germinal vesicle breakdown, lipolytic variations, and loss of the nuclear envelope in the course of maturation of oocytes. In summary, we examined the effects of thermal stress on oocyte maturation through steroid hormone contents of change identifying the molecular mechanisms of lipids metabolism. It may have the solution to further the therapy methods for disorders regarding sterility.