(1) Background: This study investigated the effects of fermented palm kernel cake (FPKC) on growth performance, serum indices, rumen fermentation and microbiota in growing-fattening beef cattle. (2) Methods: Forty-eight Angus cattle (504.50 ± 52.45 kg) were randomly divided into four groups (n = 12). The control group was fed a basal diet, while treatment groups were fed diets with 10%, 20% and 30% FPKC replacing corn and soybean meal concentrate. The experiment included a 14-day adaptation period and a 56-day formal experimental phase. (3) Results: Compared with the control, 20% FPKC significantly increased average daily gain and decreased the feed-to-gain ratio (p < 0.05). All FPKC groups had lower serum alanine aminotransferase (ALT) (p < 0.05). The 20% and 30% FPKC groups showed higher IgA and T-AOC, and lower MDA (p < 0.05) and highly significantly lower IL-1β. All FPKC groups had higher ruminal propionic acid (p < 0.05). In particular, 20% FPKC modified rumen microbial structure and increased the relative abundance of Succinivibrionaceae_UCG-002 (p < 0.05). (4) Conclusions: Replacing part of concentrate with 20% FPKC (9.1% inclusion in the total diet) improved growth performance, enhanced immune and antioxidant function in growing-fattening beef cattle, optimized rumen fermentation, and increased the relative abundance of beneficial bacteria including Succinivibrionaceae_UCG-002.

This study aims to investigate the effects of fermented Chinese herbal medicine compounds on lactation performance, serum antioxidant and immune indices, rumen fermentation parameters, and ruminal microbiota in early lactating dairy cows. The FCHM consisted mainly of Astragalus membranaceus, Angelica sinensis, Atractylodes macrocephala, and Pueraria lobata. A total of 24 pluriparous Holstein cows (37.9 +/- 2.87 kg/head & times; d of milk, 2.4 +/- 0.49 of parity, and 28.4 +/- 3.92 days in milk) were randomly divided into two groups: control group (CON, fed with a farm basal diet) and fermented Chinese herbal medicines group (FCHM, fed with the farm diet supplemented with 200 g FCHM/head & times; day). The trial consisted of an adaptation period of 14 days, followed by an experimental period of 42 days. Milk samples were collected from each cow on days 1, 21, and 42 of the trial period to determine milk composition and somatic cell count. On day 42, prior to morning feeding, blood samples were drawn from the coccygeal vein for serum biochemical, antioxidant, and immune indices, and rumen fluid was sampled using an orogastric tube to assess rumen fermentation parameters and microbial community structure. Milk yield, dry matter intake, and milk composition were measured repeatedly during the experiment, and analysed using the Linear Mixed Model. Blood and rumen fluid were sampled only on the final day, and thus analysed by one-way ANOVA. The results showed that FCHM significantly increased milk yield, milk protein, 4% fat-corrected milk and feed efficiency (p < 0.05), while significantly decreased somatic cell count (p < 0.05) compared with CON. Additionally, serum levels of superoxide dismutase, catalase, and total antioxidant capacity were significantly higher (p < 0.05), while tumour necrosis factor-alpha was significantly lower (p < 0.05) in FCHM when compared with those in CON. In the rumen of FCHM cows, the contents of propionate and microbial crude protein were significantly increased (p < 0.05), and the acetate/propionate ratio was significantly decreased (p < 0.05). Sequencing of 16S rRNA gene analysis revealed that the abundances of Bifidobacteriaceae, Gastranaerophilales, and Lachnospiraceae_UCG_004 in the rumen liquor were significantly higher (p < 0.05), while those of RF39, Saccharofermentans, Hungateiclostridiaceae, Anaerorhabdus, Tyzzerella, Erysipelotrichaceae, Oribacterium, Lachnospiraceae_AC2044_group, and Anaerorhabdus_furcosa_group were significantly lower (p < 0.05) in FCHM when compared with those in CON. In conclusion, FCHM supplementation improved lactation performance, antioxidant capacity, and immune function in early lactating dairy cows, while enhancing ruminal fermentation and modulating rumen microbiota composition.

High moisture ear corn (HMEC) is widely used in dairy cow diets, but its high moisture content can cause protein hydrolysis during fermentation. This study evaluated the effects of polyphenols extracted from the involucres of Castanea mollissima Blume (PICB) on the nutritional quality and bacterial communities of HMEC at two moisture levels: low moisture (LM, 40%) and high moisture (HM, 45%), using a 2 x 4 factorial design. HMEC was treated with 0% (CON), 0.1% (PICB1), 0.15% (PICB2), or 0.2% (PICB3) PICB. Lactic acid bacteria (15 mg/kg) were applied before ensiling. After 60 days of fermentation, crude protein (CP), dry matter (DM), lactic acid (LA), acetic acid (AA) and ammonia nitrogen (NH3-N) were highly significantly higher (p < 0.01) in LM than those in HM. DM and CP contents were also highly significantly higher (p < 0.01) in LMPICB3 than those in LMCON. LA content of LMPICB3 was highly significantly higher (p < 0.01), while neutral detergent fibre (NDF) and NH3-N content were highly significantly lower (p < 0.01) than other treatments in LM. DM, CP and LA contents were significantly higher (p < 0.01) in HMPICB3 compared to other treatments in HM. Microbial analysis revealed that Lactobacillus was most abundant in LMPICB3, positively correlated with LA. In contrast, Pantoea and Serratia were positively correlated with NH3-N content. Klebsiella was negatively correlated with CP and LA contents. In conclusion, 40% moisture content combined with 0.2% PICB addition resulted in optimal fermentation quality in HMEC, demonstrated by increased LA and CP contents along with reduced NH3-N contents.

Insulin-like growth factor 2 (IGF2) is essential for cell growth and differentiation and functions through the IGF2 receptor (IGF2R) to regulate embryonic and placental development. Exosomes that are synthesized and released from cells and play important roles in embryogenesis and placental development rely on the IGF2R for sorting and transport. However, the role of the imprinted Igf2-Igr2r axis and exosomes in the co-regulation of early placental development remains unknown. Cotyledon villi were collected from bovine placentas at different gestational ages, and the localization and expression of IGF2, IGF2R, and exosomal marker proteins were detected. Furthermore, the expression of exosomal marker factors was detected after the expression of IGF2R or IGF2 was inhibited through RNA interference or the addition of inhibitors, respectively. Our results demonstrated that IGF2, IGF2R, and the exosomal markers CD63, CD9, TSG101, and Rab11 are mainly located on the cell membrane of mononuclear trophoblast cells and binuclear trophoblast cells, which make up the cotyledon villi of the bovine placenta. The expressions of IGF2, IGF2R, and the exosomal marker proteins CD63, CD9, TSG101, and Rab11 showed a significant upward trend with increased gestation duration. Additionally, both Igf2r-knockdown and suppressing the expression of IGF2 with chromeceptin (IGF2 inhibitor) led to the downregulation of exosomal marker proteins in both bovine placental trophoblast cells (BTCs) and BTC-derived exosomes. Our study confirmed that the imprinted Igf2-Igf2r axis participates in the early development of cotyledon villi in the bovine placenta by manipulating exosome biogenesis, providing evidence for improving disorders during placental development.

Traditional pig weighing methods are costly, require driving pigs onto electronic scales, and cannot collect real-time data without interference. Pig weight estimation using deep learning often demands significant computational resources and lacks real-time capabilities, highlighting the need for a more efficient method. To overcome these challenges, this study proposes a machine learning-based approach for real-time pig weight estimation by extracting image features. The method reduces computational demands while maintaining high accuracy. The SAM2-Pig model is employed for instant segmentation of pig RGB images to extract features such as relative projection area, body length, and body width, which are crucial for accurate weight prediction. Regression models, including the BPNN with Trainlm, are used to predict pig weight based on the extracted features, achieving the best performance in our experiments. This study demonstrates that machine learning methods using RGB image features provide accurate and adaptable results, offering a viable solution for real-time pig weight estimation. This study also publicly releases the PIGRGB-Weight dataset, consisting of 9579 RGB images of pigs in a free-moving state, annotated with weight information, enabling future research and model testing. The method demonstrates remarkable stability, low computational demand, and practical applicability, making it a lightweight and effective approach for estimating pig weight in real time.

The research on automatic monitoring methods for greenhouse gases and hazardous gas emissions is currently a focal point in the fields of environmental science and climatology. Until 2023, the amount of greenhouse gases emitted by the livestock sector accounts for about 11–17% of total global emissions, with enteric fermentation in ruminants being the main source of the gases. With the escalating problem of global climate change, accurate and effective monitoring of gas emissions has become a top priority. Presently, the determination of gas emission indices relies on specialized instrumentation such as breathing chambers, greenfeed systems, methane laser detectors, etc., each characterized by distinct principles, applicability, and accuracy levels. This paper first explains the mechanisms and effects of gas production by ruminant production systems, focusing on the monitoring methods, principles, advantages, and disadvantages of monitoring gas concentrations, and a summary of existing methods reveals their shortcomings, such as limited applicability, low accuracy, and high cost. In response to the current challenges in the field of equipment for monitoring greenhouse and hazardous gas emissions from ruminant production systems, this paper outlines future perspectives with the aim of developing more efficient, user-friendly, and cost-effective monitoring instruments.

Bovine viral diarrhoea virus (BVDV) can infect cows on days 30-110 of gestation and crossing the placental barrier, resulting in persistently infected (PI) and causing significant economic losses to dairy farming. Bovine placental trophoblast cells (BTCs) are the major cells in the early chorionic tissue of the placenta and play important roles in placental resistance to viral transmission. In this study, we have confirmed that BTCs is among a groups of cell types those could be infected by BVDV in vivo, and BVDV infection stimulates the autophagic responses in BTCs and promotes the release of exosomes. Meanwhile, the exosomes derived from BTCs can be used by BVDV to spread between placental trophoblast cells, and this mode of transmission cannot be blocked by antibodies against the BVDV E2 protein, whereas the replication and spread of BVDV in BTCs can be blocked by inhibiting autophagy and exosomogenesis. Our study provides a theoretical and practical basis for scientific prediction and intervention of reproductive disorders caused by BVDV infection in cows of different gestation periods from a novel perspective.

OBJECTIVE:This study evaluated the effects of high moisture ear corn (HMEC) on production performance, milk fatty acid composition, serum antioxidant status, and immunity in primiparous dairy cows. METHODS:A total of 45 healthy primiparous Holstein cows (36.50±4.30 kg of milk/d, 201±9.00 lactating days in milk) were sorted into 3 groups: control group (CG, n = 15); 50% HMEC (replacing 50% steam-flaked corn with HMEC, n = 15); and 100% HMEC (replacing steam-flaked corn with HMEC, n = 15) on an equal dry matter (DM) basis. The study consisted of adaptation period of 14 days, followed by a formal period of 60 days. Feed intake and milk yield were recorded daily. Milk and blood samples were collected on 1, 30, and 60 d of the experimental period. RESULTS:The 50% HMEC group and 100% HMEC group significantly increased (p<0.05) milk yield and DM intake in dairy cows compared to the control group (CG). The 100% HMEC group showed an increase (p<0.05) in 4% fat-corrected milk (4% FCM). Both the 50% HMEC group and 100% HMEC group exhibited significant decreases (p<0.05) in the content of C10:0, C12:0, and C14:0 fatty acids, along with a significant increase (p<0.05) in cis-9C18:1 content. The saturated fatty acid content was significantly lower (p<0.05) in the 50% HMEC and 100% HMEC groups than that of CG. Conversely, the monounsaturated fatty acid content was higher (p<0.05) in the 50% HMEC and 100% HMEC groups than that in CG. Notably, the 100% HMEC group significantly increased (p<0.05) the serum superoxide dismutase and glutathione peroxidase content, while also decreasing the serum malondialdehyde content (p<0.05). Moreover, the 100% HMEC group significantly increased (p<0.05) the content of immunoglobulin G (IgG) and IgM. CONCLUSION:High moisture ear corn could improve production performance and milk fatty acid levels and enhance immunity and antioxidant capacity in dairy cows. These results lay the foundation for the wider application of HMEC in ruminant animal diets.

Due to the increasing costs of livestock farming, it is important to find cost-effective alternatives of feed stuffs. This study investigated the effects of high-moisture ear corn (HMEC) feeding on the production performance, serum antioxidant capacity, immunity, and ruminal fermentation and microbiome of dairy cows. Thirty pluriparous Chinese Holstein cows were randomly allocated to two groups: steam-flaked corn (SFC) and HMEC (replacement of 2 kg equal dry matter SFC) and fed for a 60 day trial. The results showed replacing SFC with HMEC significantly increased dry matter intake, milk yield, and 4% fat-corrected milk yield (p < 0.05). Serum levels of superoxide dismutase, glutathione peroxidase, and immunoglobulins G, M, and A were significantly higher, and those of creatinine and cholesterol were significantly lower, in the HMEC group than in the SFC group (p < 0.05). HMEC also significantly increased total volatile fatty acid and acetate (p < 0.05) concentrations. In both groups, the dominant phyla of ruminal bacteria were Bacteroidetes, Firmicutes, and Actinobacteria, and the dominant genera were Prevotella, NK4A214-group, and Succiniclasticum. Mogibacterium, Eubacterium nodatum group, norank-f-Lachnospiraceae, and Eubacterium brachy group were significantly enriched in the ruminal fluid of HMEC-group cows (p < 0.05). In conclusion, replacing SFC with HMEC improved production performance, antioxidant capacity, and immunity, while regulating both ruminal fermentation and the composition of the ruminal microbiome in dairy cows.

BACKGROUND:Placental exosomes are a kind of intercellular communication media secreted by placental cells during pregnancy, exosomogenesis and release are regulated by many secretory glycoproteins. CREG1 is a kind of secreted glycoprotein widely expressed in various organs and tissues of the body, which inhibits cell proliferation and enhances cell differentiation. The aim of this study was to explore the role of CREG1 in regulating exosomogenesis during the proliferation and differentiation of placental trophoblast cells in early pregnant dairy cows by targeting IGF2R and participating in regulating organoid differentiation via exosomes transport. METHODS:Molecular biological methods were firstly used to investigate the expression patterns of CREG1, IGF2R and exosomal marker proteins in early placental development of pregnant dairy cows. Subsequently, the effects of CREG1 on the formation and release of bovine placental trophoblast (BTCs) derived exosomes by targeting IGF2R were investigated. Further, the effects of CREG1 on the change of gene expression patterns along with the transport of exosomes to recipient cells and participate in regulating the differentiation of organoids were explored. RESULTS:The expression of CREG1, IGF2R and exosomal marker proteins increased with the increase of pregnancy months during the early evolution of placental trophoblast cells in dairy cows. Overexpression of Creg1 enhanced the genesis and release of exosomes derived from BTCs, while knocking down the expression of Igf2r gene not only inhibited the genesis of exosomes, but also inhibited the genesis and release of exosomes induced by overexpression of CREG1 protein. Interestingly, IGF2R can regulate the expression of CREG1 through reverse secretion. What's more, the occurrence and release of trophoblast-derived exosomes are regulated by CREG1 binding to IGF2R, which subsequently binds to Rab11. CREG1 can not only promote the formation and release of exosomes in donor cells, but also regulate the change of gene expression patterns along with the transport of exosomes to recipient cells and participate in regulating the early development of placenta. CONCLUSIONS:Our study confirmed that CREG1 is involved in the exosomogenesis and release of exosomes during the proliferation and differentiation of placental trophoblast cells in early pregnant dairy cows by targeting IGF2R, and is involved in the regulation of organoid differentiation through exosome transport.

Endometritis is a common postpartum reproductive system disease, which causes reproductive disorders and even infertility in dairy cows. High-throughput sequencing revealed that exosomal miR-433 is differentially expressed in the peripheral blood of dairy cows with endometritis. However, the specific roles of miR-433 in the occurrence and development of endometritis in dairy cows are still unclear. Therefore, a miR-433-labeled probe was used initially and found that miR-433 is mainly located in uterine cavity epithelial cells and stromal cells. The fluorescence expression of miR-433 in the uterine cavity epithelium and stromal tissues of dairy cows with endometritis is significantly weaker than that in the healthy tissues. The qRT-PCR results showed that the expressions of miR-433 in the uterine tissues of dairy cows with endometritis, LPS stimulated endometrial epithelial cells (EECs), and their derived exosomes were significantly lower than those in the uterine tissues of healthy dairy cows, EECs and their derived exosomes. Exosomal miR-433 derived from EECs transports into neighboring LPS-stimulated EECs by exosome vesicles fusion, regulating the secretion of inflammatory factors within the endometrial epithelium of dairy cows with endometritis, further influencing the development of endometritis. In conclusion, the intensity of miR-433 expression decreased in the epithelial and stromal cells of the uterine lumen and exosomes derived from endometrial epithelium in dairy cows during the occurrence of endometritis, which to some extent promotes the development and progression of endometritis in dairy cows.

卵母细胞体外成熟作为体外胚胎生产的关键技术环节,对畜牧业生产和人类辅助生殖具有重要意义.目前,该技术在生产上和临床上应用广泛,但是卵母细胞体外成熟率、受精率、优质胚胎发育率及移植后妊娠率低等问题限制了此项技术的利用效率,其中线粒体的动态分布、mtDNA拷贝数、膜电位等指标与卵母细胞发育成熟密切相关.本文简要介绍了卵母细胞成熟机制和体内外成熟差异,概括了线粒体在卵母细胞成熟过程中的调控机制以及外源线粒体调节剂在卵母细胞体外成熟体系中的应用情况和效果,以期为提高体外胚胎生产技术效率提供有力的理论依据和技术支撑.

In order to study the smart management of dairy farms, this study combined Internet of Things (IoT) technology and dairy farm daily management to form an intelligent dairy farm sensor network and set up a smart dairy farm system (SDFS), which could provide timely guidance for dairy production. To illustrate the concept and benefits of the SDFS, two application scenarios were sampled: (1) Nutritional grouping (NG): grouping cows according to the nutritional requirements by considering parities, days in lactation, dry matter intake (DMI), metabolic protein (MP), net energy of lactation (NEL), etc. By supplying feed corresponding to nutritional needs, milk production, methane and carbon dioxide emissions were compared with those of the original farm grouping (OG), which was grouped according to lactation stage. (2) Mastitis risk prediction: using the dairy herd improvement (DHI) data of the previous 4 lactation months of the dairy cows, logistic regression analysis was applied to predict dairy cows at risk of mastitis in successive months in order to make suitable measurements in advance. The results showed that compared with OG, NG significantly increased milk production and reduced methane and carbon dioxide emissions of dairy cows (p < 0.05). The predictive value of the mastitis risk assessment model was 0.773, with an accuracy of 89.91%, a specificity of 70.2%, and a sensitivity of 76.3%. By applying the intelligent dairy farm sensor network and establishing an SDFS, through intelligent analysis, full use of dairy farm data would be made to achieve higher milk production of dairy cows, lower greenhouse gas emissions, and predict in advance the occurrence of mastitis of dairy cows.

本试验旨在研究带轴高湿玉米(HMEC)替代压片玉米对奶牛生产性能、血清生化指标、免疫功能和抗氧化能力的影响.选取60头胎次(2～4胎)、泌乳天数[(83.9±16.9)d]和产奶量[(33.4±7.5)kg/d]相近的健康经产荷斯坦奶牛,随机分为2组,每组30头.对照组饲喂基础饲粮,试验组将基础饲粮中的压片玉米按照干物质基础等量替换为HMEC进行饲喂.预试期14 d,正试期40 d(试验组饲喂30 d含HMEC饲粮,之后饲喂基础饲粮).结果显示:1)试验组和对照组之间奶牛生产性能及乳成分无显著差异(P＞0.05).2)试验组和对照组之间第1、20和40天和第1～40天血清谷丙转氨酶活性和白蛋白、葡萄糖和甘油三酯含量无显著差异(P＞0.05).3)试验组第20天血清免疫球蛋白G(IgG)和免疫球蛋白A(IgA)含量显著高于对照组(P＜0.05),试验组和对照组之间第1、40天和第1～40天血清IgG和IgA含量均无显著差异(P＞0.05).饲喂时间对血清IgG、IgA和免疫球蛋白M(IgM)含量有显著影响(P＜0.05).4)试验组第20天血清总抗氧化能力(T-AOC)和超氧化物歧化酶(SOD)活性显著高于对照组(P＜0.05),试验组和对照组之间第1、40天和第1～40天血清T-AOC和SOD活性均无显著差异(P＞0.05).饲喂时间对血清T-AOC和SOD、谷胱甘肽过氧化物酶活性有显著影响(P＜0.05).5)与对照组相比,试验组的牛奶收入增加了 4.25元/(d·头),经济效益增加了5.65元/(d·头).综上所述,用HMEC替代饲粮中压片玉米饲喂奶牛不影响奶牛的生产性能及乳成分,但能提高奶牛的免疫功能和抗氧化能力,增加奶牛场的经济效益.

专业教师是推动高校开展"课程思政"建设的核心因素,而高校教师党支部在推动"课程思政"建设中起着承担价值引领、提供组织保障、发挥桥梁沟通的作用.但从目前实际工作成效来看,高校教师党支部仍存在作用发挥不充分的问题.新形势下,高校教师党支部应以模范党员专业教师为导向、以提升专业教师素质为抓手、以树立榜样为标尺、以强化机制为保障,推动高校"课程思政"建设,打造全员、全过程、全方位育人的"大思政"格局.

Maize (Zea mays L) is one of the most widely cultivated crops used as energy feeds. The aim of this study was to evaluate the effects of two lactic acid bacteria additives on the fermentation quality and bacterial community of high moisture ear corn (HMEC) silage at different moisture levels. The study utilized corn kernels and cobs harvested at the stage of complete ripeness as the primary material. The cob was crushed and divided into three treatment groups: an untreated control group (CK), a group treated with a mixture of Lactobacillus plantarum and Lactobacillus brucei (TQ), or a group treated with a mixture of Lactococcus lactis and Lactobacillus brucei (KT). Moisture contents were adjusted to 37.5% (L), 42.5% (M) or 47.5% (H) and then silaged for 180 days. Compared to CK, TQ, and KT elevated the dry matter, crude protein, starch, lactic and acetic acid content of HMEC and reduced the pH, neutral detergent fiber, acid detergent fiber and ammonia nitrogen content (p < 0.05). Even though both additives improved the bacterial community structure after fermentation, KT experienced the greater enhancement. At a phylum and genus level, KT had the higher relative abundance of Firmicutes and Lactobacillus, respectively. Compared with the group of 37.5% (L) moisture content, the 42.5% (M) and 47.5% moisture content (H) group increased lactic acid, acetic acid and ammonia nitrogen concentrations and reduced the pH value (p < 0.05). In conclusion, the addition of TQ and KT at the appropriate moisture content might be helpful for producing high-quality HMEC. Among the three moisture contents, 42.5% (M) moisture content provides the best silage qualities.

The molecular mechanisms underlying heat stress tolerance in animals to high temperatures remain unclear. This study identified the differentially expressed mRNA isoforms which narrowed down the most reliable DEG markers and molecular pathways that underlie the mechanisms of thermoregulation. This experiment was performed on Sprague Dawley rats housed at 22 °C (control group; CT), and three acute heat-stressed groups housed at 42 °C for 30 min (H30), 60 min (H60), and 120 min (H120). Earlier, we demonstrated that acute heat stress increased the rectal temperature of rats, caused abnormal changes in the blood biochemical parameters, as well as induced dramatic changes in the expression levels of genes through epigenetics and post-transcriptional regulation. Transcriptomic analysis using RNA-Sequencing (RNA-Seq) data obtained previously from blood (CT and H120), liver (CT, H30, H60, and H120), and adrenal glands (CT, H30, H60, and H120) was performed. The differentially expressed mRNA isoforms (DEIs) were identified and annotated by the CLC Genomics Workbench. Biological process and metabolic pathway analyses were performed using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. A total of 225, 5764, and 4988 DEIs in the blood, liver, and adrenal glands were observed. Furthermore, the number of novel differentially expressed transcript lengths with annotated genes and novel differentially expressed transcript with non-annotated genes were 136 and 8 in blood, 3549 and 120 in the liver, as well as 3078 and 220 in adrenal glands, respectively. About 35 genes were involved in the heat stress response, out of which, Dnaja1, LOC680121, Chordc1, AABR07011951.1, Hsp90aa1, Hspa1b, Cdkn1a, Hmox1, Bag3, and Dnaja4 were commonly identified in the liver and adrenal glands, suggesting that these genes may regulate heat stress response through interactions between the liver and adrenal glands. In conclusion, this study would enhance our understanding of the complex underlying mechanisms of acute heat stress, and the identified mRNA isoforms and genes can be used as potential candidates for thermotolerance selection in mammals.

[目的]为研究奶牛胎盘发育提供基础依据.[方法]使用CoCl2构建奶牛胎盘滋养层细胞低氧模型,并筛选出试验所需最适CoCl2浓度;实时荧光定量PCR方法检测低氧对胎盘滋养层细胞胎盘生长因子(Placental growth factor,PLGF)mRNA表达的影响;显微镜观察低氧对Transwell小室中细胞迁移和浸润能力的影响;采用蛋白质印迹法(Western Blot)检测细胞中E-钙黏蛋白(E-Cadherin)的表达.[结果]通过检测细胞中低氧诱导因子-1a表达量确定试验所需的最适CoCl2浓度为200 μg/mL;Trans well小室法检测发现,低氧环境下细胞增殖缓慢,伪足数量和合胞体数量减少,迁移减缓,迁移率下降;实时荧光定量PCR结果显示,PLGF mRNA的表达并不受氧分压变化的影响;Western Blot结果显示E-Cadherin的表达量在低氧环境下表现出显著下降趋势.[结论]低氧能够抑制奶牛胎盘滋养层细胞的增殖、迁移与E-Cadherin的表达,但对PLGF mRNA的表达无显著作用.

Endometritis affects the reproductive capacity of dairy cows and leads to serious economic losses in dairy farming. Clarification of the pathogenesis of endometritis is necessary to improve the reproductive efficiency of dairy cows. Exosomes and their miRNAs have been proven to play an important role in inflammatory regulation. Exosomal miR-218 is a differentially expressed miRNA found in endometrial epithelial cells (EECs) under endometrial inflammation. Therefore, we investigated the expression of miR-218 in the uterine tissue of dairy cows, lipopolysaccharide (LPS) treated EECs, exosomal vesicles, and regulation of exosomal miR-218 by targeting TGIF-2 inducible factor homology frame 2 (TGIF2)/transforming growth factor-beta (TGF-I3). The expression of miR-218 was suppressed in inflammatory uterine tissues and LPS treated EECs. The expression of TGIF2 and TGF-I3 in inflammatory uterine tissues and LPS treated EECs was significantly higher than those in healthy uterine tissues and EECs (p < 0.01). Interestingly, miR-218 derived from donor cells was found to regulate the expression of the target gene TGIF2 in recipient cells through the fusion of exosomes. Concurrently, the expression of its target gene TGIF2 was also suppressed by miR-218 in donor cells resulting in fewer TGIF2 being transported into recipient cells with exosomal fusion. This may be a novel mechanism of miRNAs-mediated regulation and provides a new reference for analyzing the pathogenesis of endometritis in dairy cows.