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Rapid Detection of Somatic Cell Count Based on Hybrid Variable Selection Method
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作者 Shen Weizheng Cui Xiang +6 位作者 Wang Yan Nie Debao Zhang Qinggang Zheng Wei Sun Jian Yang Xin Dai Baisheng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第3期59-73,共15页
Somatic cell count detection is the daily work of dairy farms to monitor the health of cows.The feasibility of applying near-infrared spectroscopy to somatic cell count detection was researched in this paper.Milk samp... Somatic cell count detection is the daily work of dairy farms to monitor the health of cows.The feasibility of applying near-infrared spectroscopy to somatic cell count detection was researched in this paper.Milk samples with different somatic cell counts were collected and preprocessing methods were studied.Variable selection algorithm based on hybrid strategy and modelling method based on ensemble learning were explored for somatic cell count detection.Detection model was used to diagnose subclinical mastitis and the results showed that near-infrared spectroscopy could be a tool to realize rapid detection of somatic cell count in milk. 展开更多
关键词 near-infrared spectroscopy somatic cell count MASTITIS rapid detection
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Whole-genome methylation analysis reveals epigenetic variation between wild-type and nontransgenic cloned,ASMT transgenic cloned dairy goats generated by the somatic cell nuclear transfer 被引量:1
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作者 Hao Wu Wendi Zhou +10 位作者 Haijun Liu Xudai Cui Wenkui Ma Haixin Wu Guangdong Li Likai Wang Jinlong Zhang Xiaosheng Zhang Pengyun Ji Zhengxing Lian Guoshi Liu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期98-113,共16页
Background:SCNT(somatic cell nuclear transfer)is of great significance to biological research and also to the livestock breeding.However,the survival rate of the SCNT cloned animals is relatively low compared to other... Background:SCNT(somatic cell nuclear transfer)is of great significance to biological research and also to the livestock breeding.However,the survival rate of the SCNT cloned animals is relatively low compared to other transgenic methods.This indicates the potential epigenetic variations between them.DNA methylation is a key marker of mammalian epigenetics and its alterations will lead to phenotypic differences.In this study,ASMT(acetylserotonin-Omethyltransferase)ovarian overexpression transgenic goat was produced by using SCNT.To investigate whether there are epigenetic differences between cloned and WT(wild type)goats,WGBS(whole-genome bisulfite sequencing)was used to measure the whole-genome methylation of these animals.Results:It is observed that the different m Cp G sites are mainly present in the intergenic and intronic regions between cloned and WT animals,and their CG-type methylation sites are strongly correlated.DMR(differentially methylated region)lengths are located around 1000 bp,mainly distributed in the exonic,intergenic and intronic functional domains.A total of 56 and 36 DMGs(differentially methylated genes)were identified by GO and KEGG databases,respectively.Functional annotation showed that DMGs were enriched in biological-process,cellularcomponent,molecular-function and other signaling pathways.A total of 10 identical genes related to growth and development were identified in GO and KEGG databases.Conclusion:The differences in methylation genes among the tested animals have been identified.A total of 10 DMGs associated with growth and development were identified between cloned and WT animals.The results indicate that the differential patterns of DNA methylation between the cloned and WT goats are probably caused by the SCNT.These novel observations will help us to further identify the unveiled mechanisms of somatic cell cloning technology,particularly in goats. 展开更多
关键词 Acetylserotonin-O-methyltransferase Dairy goat DNA methylation Gene editing somatic cell nuclear transfer
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Transcriptome‑wide mapping of milk somatic cells upon subclinical mastitis infection in dairy cattle
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作者 Vittoria Bisutti Nuria Mach +7 位作者 Diana Giannuzzi Alice Vanzin Emanuele Capra Riccardo Negrini Maria Elena Gelain Alessio Cecchinato Paolo Ajmone‑Marsan Sara Pegolo 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2630-2648,共19页
Background Subclinical intramammary infection(IMI)represents a significant problem in maintaining dairy cows’health.Disease severity and extent depend on the interaction between the causative agent,environment,and ho... Background Subclinical intramammary infection(IMI)represents a significant problem in maintaining dairy cows’health.Disease severity and extent depend on the interaction between the causative agent,environment,and host.To investigate the molecular mechanisms behind the host immune response,we used RNA-Seq for the milk somatic cells(SC)transcriptome profiling in healthy cows(n=9),and cows naturally affected by subclinical IMI from Proto-theca spp.(n=11)and Streptococcus agalactiae(S.agalactiae;n=11).Data Integration Analysis for Biomarker discov-ery using Latent Components(DIABLO)was used to integrate transcriptomic data and host phenotypic traits related to milk composition,SC composition,and udder health to identify hub variables for subclinical IMI detection.Results A total of 1,682 and 2,427 differentially expressed genes(DEGs)were identified when comparing Prototheca spp.and S.agalactiae to healthy animals,respectively.Pathogen-specific pathway analyses evidenced that Proto-theca’s infection upregulated antigen processing and lymphocyte proliferation pathways while S.agalactiae induced a reduction of energy-related pathways like the tricarboxylic acid cycle,and carbohydrate and lipid metabolism.The integrative analysis of commonly shared DEGs between the two pathogens(n=681)referred to the core-mastitis response genes,and phenotypic data evidenced a strong covariation between those genes and the flow cytometry immune cells(r2=0.72),followed by the udder health(r2=0.64)and milk quality parameters(r2=0.64).Variables with r≥0.90 were used to build a network in which the top 20 hub variables were identified with the Cytoscape cyto-hubba plug-in.The genes in common between DIABLO and cytohubba(n=10)were submitted to a ROC analysis which showed they had excellent predictive performances in terms of discriminating healthy and mastitis-affected animals(sensitivity>0.89,specificity>0.81,accuracy>0.87,and precision>0.69).Among these genes,CIITA could play a key role in regulating the animals’response to subclinical IMI.Conclusions Despite some differences in the enriched pathways,the two mastitis-causing pathogens seemed to induce a shared host immune-transcriptomic response.The hub variables identified with the integrative approach might be included in screening and diagnostic tools for subclinical IMI detection. 展开更多
关键词 Data integration Immune response Milk somatic cells RNA-sequencing Subclinical mastitis
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Udder Health Status of First Parity Dairy Cows in Early-Lactation Based on Somatic Cell Count Categories
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作者 Găvan Constantin Riza Mihaela 《Open Journal of Animal Sciences》 2023年第3期398-407,共10页
The main aim of this study was to investigate the prevalence of intramammary infection (IMI) in early-lactation of primiparous cows using milk recording cow composite somatic cell count (CSCC) categories (combining th... The main aim of this study was to investigate the prevalence of intramammary infection (IMI) in early-lactation of primiparous cows using milk recording cow composite somatic cell count (CSCC) categories (combining the first 2 milk recording results after calving). Another aim was to evaluate the milk urea (MU) content as a potential supplementary indicator to SCC or CSCC for the identification of IMI in primiparous cows after calving. This retrospective observational study was conducted on records of test-day of primiparous cows over a period of 6 years (January 2016 to December 2021. The SCC data for 158 Holstein Friesian primiparous cows, with their first milk recording 5 to 35 days after calving and their second milk recording 28 to 56 days in milk (DIM), were identified. Each primiparous cow was assigned a CSCC category (low-low, low-high, high-low or high-high) based on the CSCC at the first 2 milking recordings using the following cut-offs: ≤150,000 cells/ml (low), >150,000 cells/ml (high). The association between CSCC categories and MV content was analyzed using correlation models. At the first milk recording, a proportion of 63.29% was in the low SCC category, and the rest (36.71%) was in the high SCC category. At the second milk recording, a proportion of primiparous cows in CSCC categories was 59.49%, 3.80%, 27.85% and 8.86% in low-low, low-high, high-low and high-high, respectively. At the second milk recording, a proportion of 12.66% of primiparous cows was in the high CSCC category and a proportion of 87.34% of primiparous cows was in the low CSCC category, indicating a poor and a good udder health, respectively. The association of SCC with MU content in low and in high SCC categories at the first milk recording was positive and moderate (+0.49) and negative and strong (-0.97), respectively. The association of CSCC categories with MU contents at the second milk recording was inconclusive. We concluded that CSCC categories may be a useful tool for identifying success and problems regarding the udder health of primiparous cows in early lactation. 展开更多
关键词 Intramammary Infection somatic cell Count Composite somatic cell Count Milk Urea Content
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Single‑cell sequencing reveals the reproductive variations between primiparous and multiparous Hu ewes
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作者 Ting Ge Yifan Wen +3 位作者 Bo Li Xiaoyu Huang Shaohua Jiang Enping Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期614-631,共18页
Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of farming.Revealing the genetic mechanisms underlying differences in the litter size is imp... Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of farming.Revealing the genetic mechanisms underlying differences in the litter size is important for the selection and breeding of highly prolific ewes.Hu sheep,a high-quality Chinese sheep breed,is known for its high fecundity and is often used as a model to study prolificacy traits.In the current study,animals were divided into two groups according to their delivery rates in three consecutive lambing seasons(namely,the high and low reproductive groups with≥3 lambs and one lamb per season,n=3,respectively).The ewes were slaughtered within 12 h of estrus,and unilateral ovarian tissues were collected and analyzed by 10×Genomics single-cell RNA sequencing.Results A total of 5 types of somatic cells were identified and corresponding expression profiles were mapped in the ovaries of each group.Noticeably,the differences in the ovary somatic cell expression profiles between the high and low reproductive groups were mainly clustered in the granulosa cells.Furthermore,four granulosa cell subtypes were identified.GeneSwitches analysis revealed that the abundance of JPH1 expression and the reduction of LOC101112291 expression could lead to different evolutionary directions of the granulosa cells.Additionally,the expression levels of FTH1 and FTL in mural granulosa cells of the highly reproductive group were significantly higher.These genes inhibit necroptosis and ferroptosis of mural granulosa cells,which helps prevent follicular atresia.Conclusions This study provides insights into the molecular mechanisms underlying the high fecundity of Hu sheep.The differences in gene expression profiles,particularly in the granulosa cells,suggest that these cells play a critical role in female prolificacy.The findings also highlight the importance of genes such as JPH1,LOC101112291,FTH1,and FTL in regulating granulosa cell function and follicular development. 展开更多
关键词 Granulosa cells Hu sheep Lambing number Ovarian somatic cells Single-cell RNA sequencing
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Human Pro-insulin Transgenic Calf Derived from Somatic Cell Nuclear Transfer 被引量:5
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作者 杨东山 郭旭东 +6 位作者 海棠 杜晨光 王建国 仓明 刘东军 李喜和 旭日干 《Zoological Research》 CAS CSCD 北大核心 2007年第4期409-416,共8页
The current study was undertaken to evaluate the possibility of producing a human pro-insulin transgenic cow by means of somatic cell nuclear transfer (SCNT). A double selection system, Neomycin resistance (Neo^r)... The current study was undertaken to evaluate the possibility of producing a human pro-insulin transgenic cow by means of somatic cell nuclear transfer (SCNT). A double selection system, Neomycin resistance (Neo^r) gene and enhanced green fluorescent protein (EGFP) gene linked through an inner ribosomal entry site (IRES) sequence directed by a Cytomegalovirus (CMV) promoter, was used for enrichment and selection of the transgenic cells and preimplantation embryos. Transgenes were introduced into bovine fetal fibroblast cells (BFF) cultured in vitro through electroporation (900 V/cm, 5 ms). Transgenic bovine fibroblast cells (TBF) were enriched through addition of G418 in culture medium (800 μg/mL). Before being used as a nuclear donor, the TBF cells were either cultured in normal conditions (10% FBS) or treated with serum starvation (0.5% FBS for 2-4 days) followed by 10 hours recovery for G1 phase synchronization. Transgenic cloned embryos were produced through GFP-expressing cell selection and SCNT. The results were the percentage of blastocyst development following SCNT was lower using TBF than BFF cells (23.2% VS 35.2%, P 〈 0.05). No difference in the percentage of cloned blastocysts between the two groups of transgenic nuclear donor of normal and starvation cultures were observed (23.2% VS 18.9%, P 〉 0.05). Two to four GFP-expressing blastocysts were transferred into the uterus of each synchronised recipient. One pregnancy from of seven recipients (21 embryos) was confirmed by rectum palpation 60 days after embryo transfer and one recipient has given birth to a calf at term. PCR and DNA sequencing analysis confirmed that the calf was produced using human proinsulin transgenic animal. 展开更多
关键词 somatic cell nuclear transfer Human pro-insulin EGFP Transgenic calf
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Embryonic stem cells generated by nuclear transfer of human somatic nuclei into rabbit oocytes 被引量:57
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作者 YINGCHEN ZHIXuHE +19 位作者 AILIANLIU KAIWANG WENWEIMAO JIANKINCHU YONGLU ZHENGFUFANG YINGTANGSHI QINGZHANGYANG DAYUANCHEN MINKANGWANG JINSONGLI SHAOLIANGHUANG XIANGYINKONG YAOZHOUSHI ZHIQIANGWANG JIAHuIXIA ZHIGAOLONG ZHIGANGXUE WENXIANGDING HUIZHENSHENG 《Cell Research》 SCIE CAS CSCD 2003年第4期251-263,共13页
To solve the problem of immune incompatibility, nuclear transplantation has been envisaged as a means to produce cells or tissues for human autologous transplantation. Here we have derived embryonic stem cells by the ... To solve the problem of immune incompatibility, nuclear transplantation has been envisaged as a means to produce cells or tissues for human autologous transplantation. Here we have derived embryonic stem cells by the transfer of human somatic nuclei into rabbit oocytes. The number of blastocysts that developed from the fused nuclear transfer was comparable among nuclear donors at ages of 5, 42, 52 and 60 years, and nuclear transfer (NT) embryonic stem cells (ntES cells) were subsequently derived from each of the four age groups. These results suggest that human somatic nuclei can form ntES cells independent of the age of the donor. The derived ntES cells are human based on karyotype, isogenicity, in situ hybridization, PCR and immunocytochemistry with probes that distinguish between the various species. The ntES cells maintain the capability of sustained growth in an undifferentiated state, and form embryoid bodies, which, on further induction, give rise to cell types such as neuron and muscle, as well as mixed cell populations that express markers representative of all three germ layers. Thus, ntES cells derived from human somatic cells by NT to rabbit eggs retain phenotypes similar to those of conventional human ES cells, including the ability to undergo multilineage cellular differentiation. 展开更多
关键词 nuclear transfer (NT) somatic cell nuclear transfer (SCNT) embryonic stem cells (ES cell) therapeutic cloning rabbit oocyte.
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Relationship of Somatic Cell Count with Milk Yield and Composition in Chinese Holstein Population 被引量:6
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作者 GUO Jia-zhong LIU Xiao-lin XU A-juan XIA Zhi 《Agricultural Sciences in China》 CAS CSCD 2010年第10期1492-1496,共5页
The objective of this study was to analyze the relationship of somatic cell count (SCC) with milk yield, fat and protein percentage, fat and protein yield using analysis of variance and correlation analysis in Chine... The objective of this study was to analyze the relationship of somatic cell count (SCC) with milk yield, fat and protein percentage, fat and protein yield using analysis of variance and correlation analysis in Chinese Holstein population. The 10 524 test-day records of 568 Chinese Holstein Cattle were obtained from 2 commercial herds in Xi'an region of China during February 2002 to March 2009. Milk yield, fat percentage, fat and protein yield initially increased and then dropped down with parity, whereas protein percentage decreased and SCC increased. Analysis of variance showed highly significant effects of different subclasses SCC on milk yield and composition (P〈 0.01). Compared with milk yield with SCC ≤ 200 000 cells mL-1, milk yield losses with SCC of 200 000-500 000 cells mL-1, 501000-1 000 000 cells mL-1, ≥ 1 000 000 cells mL-1 were 0.387, 0.961 and 2.351 kg, respectively. The highly significant negative correlation coefficient between somatic cell score (SCS) and milk and protein yield, milk yield and fat and protein percentage, protein percentage and fat yield were -0.084, -0.037, -0.061, -0.168, and -0.088, respectively (P〈 0.01). The highly significant positive correlation coefficients between SCS and fat yield and fat and protein percentage, milk yield and fat and protein yield, fat percentage and protein percentage and fat yield, protein yield and protein percentage and fat yield were 0.041, 0.177, 0.105, 0.771, 0.865, 0.122, 0.568, 0.318, and 0.695, respectively (P〈 0.01). There was no significant relationship between fat percentage and protein yield (P 〉 0.05). The results of the present study first time provide the relevant base-line data for assessing milk production at Xi'an region of China. 展开更多
关键词 Holstein cattle milk yield milk composition somatic cell count somatic cell score
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PiggyBac Transposon Mediated Efficient eGFP Expression in Porcine Somatic Cells and Cloned Embryos 被引量:2
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作者 Luo Yi-bo Zhang Li +6 位作者 Zhu Jiang Wu Mei-ling Huan Yan-jun Yin Zhi Mu Yan-shuang Xia Ping LiuZhong-hua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第2期33-41,共9页
PiggyBac transposon has demonstrated its long-term and stable transposition on genomes of various species but lacking of the evidence on farm animal genomes. In this study, we constructed a piggyBac transposon marked ... PiggyBac transposon has demonstrated its long-term and stable transposition on genomes of various species but lacking of the evidence on farm animal genomes. In this study, we constructed a piggyBac transposon marked with enhanced green fluorescent protein (eGFP) and showed efficient transposition in porcine somatic cells and cloned embryos. Our results demonstrated that piggyBac transposase could efficiently catalyze transposition in porcine fetal fibroblast cells, as well as in embryos. PiggyBac transposition generated 18-fold more eGFP-positive cell colonies compared to pEGFP-C1 random insertion mutagenesis, but excessive transposase might affect the transfection rate. Also piggyBac mediated 4-fold more eGFP expression than random insertion in cells and 17-fold in cloned embryos at mRNA level. When the mutagenized cells were used for somatic cell nuclear transfer (SCNT), the cleavage rate and blastocyst rate of constructed embryos harboring piggyBac transposition had no difference with random insertion group. This study provides key information on the piggyBac transposon system as a tool for creating transgenic pigs. 展开更多
关键词 piggyBac transposon EGFP somatic cell nuclear transfer PIG TRANSGENE
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Cumulus-specific genes are transcriptionally silent following somatic cell nuclear transfer in a mouse model 被引量:1
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作者 TONG Guo-qing HENG Boon-chin NG Soon-chye 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第8期533-539,共7页
This study investigated whether four cumulus-specific genes: follicular stimulating hormone receptor (FSHr), hyaluronan synthase 2 (Has2), prostaglandin synthase 2 (Ptgs2) and steroidogenic acute regulator protein (St... This study investigated whether four cumulus-specific genes: follicular stimulating hormone receptor (FSHr), hyaluronan synthase 2 (Has2), prostaglandin synthase 2 (Ptgs2) and steroidogenic acute regulator protein (Star), were correctly reprogrammed to be transcriptionally silent following somatic cell nuclear transfer (SCNT) in a murine model. Cumulus cells of C57×CBA F1 female mouse were injected into enucleated oocytes, followed by activation in 10 μmol/L strontium chloride for 5 h and subsequent in vitro culture up to the blastocyst stage. Expression of cumulus-specific genes in SCNT-derived embryos at 2-cell, 4-cell and day 4.5 blastocyst stages was compared with corresponding in vivo fertilized embryos by real-time PCR. It was demonstrated that immediately after the first cell cycle, SCNT-derived 2-cell stage embryos did not express all four cumulus-specific genes, which continually remained silent at the 4-cell and blastocyst stages. It is therefore concluded that all four cumulus-specific genes were correctly reprogrammed to be silent following nuclear transfer with cumulus donor cells in the mouse model. This would imply that the poor preimplantation developmental competence of SCNT embryos derived from cumulus cells is due to incomplete reprogramming of other embryonic genes, rather than cumulus-specific genes. 展开更多
关键词 somatic cell nuclear transfer (SCNT) Nuclear reprogramming EMBRYO DEVELOPMENT
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Effect of Rare Earth Elements on the Induction Frequency of the Somatic Cell Embryo in The Fruit of Chinese Wolfoerry 被引量:1
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作者 杨汉民 杜琳 《Journal of Rare Earths》 SCIE EI CAS CSCD 1994年第1期63-66,共4页
A part of lanthanides could raise the induction fraquency(IF) of the somatic cell embryo(SCE) in the fruit of Chinese wolfbeny. The effect of thorium and yttrium used for this purpose is not obvious and even plays a r... A part of lanthanides could raise the induction fraquency(IF) of the somatic cell embryo(SCE) in the fruit of Chinese wolfbeny. The effect of thorium and yttrium used for this purpose is not obvious and even plays a role of inhibition when they are used with a concentration of more than 4 ppm.When the combinations of different rare earth elements (RE) are used, the diversity of the effects amongthem is large. Some of them help to raise the iF of the SCE while the others inhibit the generation of SCE.The mischmetal results in the best effect, giving a relative IF of 295.4%. 展开更多
关键词 Rare earth elements Mischemtal somatic cell embryo Fruit of Chinese wolfberry.
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Genetic parameters for somatic cell score and production traits in the fi rst three lactations of Chinese Holstein cows
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作者 ZHAO Fu-ping GUO Gang +3 位作者 WANG Ya-chun GUO Xiang-yu ZHANG Yuan DU Li-xin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第1期125-130,共6页
The objectives of this study were to estimate genetic parameters of lactation average somatic cell scores (LSCS) and examine genetic associations between LSCS and production traits in the first three lactations of C... The objectives of this study were to estimate genetic parameters of lactation average somatic cell scores (LSCS) and examine genetic associations between LSCS and production traits in the first three lactations of Chinese Holstein cows using single-parity multi-trait animal model and multi-trait repeatability animal model. There were totally 273605 lactation records of Chinese Holstein cows with first calving from 2001 to 2012. Heritability estimates for LSCS ranged from 0.144 to 0.187. Genetic correlations between LSCS and 305 days milk, protein percentage and fat percentage were -0.079, -0.082 and -0.135, respectively. Phenotypic correlation between LSCS and 305 days milk yield was negative (-0.103 to -0.190). Genetic correlation between 305 days milk and fat percentage or protein percentage was highly negative. Genetic correlation between milk fat percentage and milk protein percentage was highly favorable. Heritabilities of production traits decreased with increase of parity, whereas heritability of LSCS increased with increase of parity. 展开更多
关键词 somatic cell score genetic parameters Chinese Holstein single-parity multi-trait animal model multi-traitrepeatability animal model
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Mapping of Microsatellite SW943 to Porcine Chromosome 12p11-(2/3p13) Using Primed in situ Synthesis and Somatic Cell Hybrid Panel
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作者 LIU Bang, WANG Yong-qiang, ZHANG Qing-de, YU Mei, ZHAO Shu-hong, XIONG Tong-an and LI Kui(Laboratory of Molecular Biology and Animal Breeding, School of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070 ,P. R . China) 《Agricultural Sciences in China》 CAS CSCD 2002年第5期589-593,共5页
The porcine microsatellite SW943 was regionally localized on 12p11-(2/3p13) by the two methods: the Primed in situ (PRINS) labelling on the pachytene bivalents of pigs using the Dig-11-dUTP as the report molecule and ... The porcine microsatellite SW943 was regionally localized on 12p11-(2/3p13) by the two methods: the Primed in situ (PRINS) labelling on the pachytene bivalents of pigs using the Dig-11-dUTP as the report molecule and pig X rodent Somatic Cell Hybrid Panel (SCHP) which contains 27 cell lines through PCR amplification. Advantages and disadvantages of the two methods for physical mapping of microsatellites were also discussed. 展开更多
关键词 Primer in situ synthesis somatic cell hybrid panel Microsatellites Physical mapping Pigs
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discs large regulates somatic cyst cell survival and expansion in Drosophila testis
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作者 Fani Papagiannouli Bernard M Mechler 《Cell Research》 SCIE CAS CSCD 2009年第10期1139-1149,共11页
Gonad development requires a coordinated soma-germline interaction that ensures renewal and differentiation of germline and somatic stem cells to ultimately produce mature gametes. The Drosophila tumour suppressor gen... Gonad development requires a coordinated soma-germline interaction that ensures renewal and differentiation of germline and somatic stem cells to ultimately produce mature gametes. The Drosophila tumour suppressor gene discs large (dig) encodes a septate junction protein functioning during epithelial polarization, asymmetric neuroblast division, and formation of neuromuscular junctions. Here, we report the role of dig in testis development and its critical function in somatic cyst cells (SCCs). In these cells dig is primarily required for their survival and expansion, and contributes to spermatocyte cyst differentiation. Cell death primarily occurred in SCCs at the end of spermatogonial amplification at a time when Dig becomes restricted in wild-type (wt) testes to the distal somatic cells capping the growing spermatocyte cysts. RNAi depletion of dig transcripts in early SCCs fully prevented testis development, whereas depletion in late SCCs resulted in a breakdown of spermatocyte cyst structure and germ cell individualization. Specific dig expression in SCCs resulted in developmental rescue of dig mutant testes, whereas its expression in germ cells exerted no such effect, dig overexpression in wt testes led to spermatocyte cyst expansion at the expense of spermatogonial cysts. Our data demonstrate that dig is essentially required in SCCs for their survival, expansion, and differentiation, and for the encapsulation of the germline cells. 展开更多
关键词 discs large DROSOPHILA testis formation somatic cyst cells
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Segmentation of Somatic Cells in Goat Milk Using Color Space CIELAB
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作者 Gabriel Jesus Alves de Melo Viviani Gomes +2 位作者 Camila Costa Baccili Luiz Alberto Luz de Almeida AntonioCezar de Castro Lima 《Journal of Agricultural Science and Technology(A)》 2014年第10期865-873,共9页
Somatic cell counts (SCCs) levels indicate the occurrence of infections in goat udders and are related to the productivity of goat milk, cheese and yoghurt. This work presents a segmentation method for counting soma... Somatic cell counts (SCCs) levels indicate the occurrence of infections in goat udders and are related to the productivity of goat milk, cheese and yoghurt. This work presents a segmentation method for counting somatic cells in goat milk images, intending to detect an infection known as mastiffs, which is the major cause of loss in dairy farming. The image segmentation procedure is devised by using the lab color space and the watershed transform. A large number of samples under variable preparation conditions are treated with the proposed method. A comparison between manual and the proposed technique is presented. Promising results indicates that video-microscopy systems may be employed to develop automated SCC for goat milk. 展开更多
关键词 Image processing distance transform SEGMENTATION somatic cells.
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Somatic Cell Count in Relation to Udder and Morphometry in Holstein Friesian Dairy Cows
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作者 Găvan Constantin Riza Mihaela 《Journal of Agricultural Science and Technology(A)》 2021年第1期47-52,共6页
In the present study authors present some aspects regarding udder health as well as the udder teat morphometry.The udder health was defined on the basis of somatic cell count(SCC)in milk.The morphometry parameters inc... In the present study authors present some aspects regarding udder health as well as the udder teat morphometry.The udder health was defined on the basis of somatic cell count(SCC)in milk.The morphometry parameters included:distance from rear teat-tip to the floor,distance from fore teat-tip to the floor,udder depth,udder length,udder width,udder volume,fore teat length,rear teat length,fore teat diameter,and rear teat diameter.The present investigation involved 92 Holstein Friesian cows,from an experimental herd.Considering particular structural elements of a cow udder,three location groups were distinguished:1st,2nd,and 3rd(L_(1),L_(2) and L_(3) respectively).From the study result,primiparous cows(L_(1) group)were characterized by a relatively low SCC in milk,as compared to multiparous cows(L_(2) group or L_(3) group).The cows in the 3rd lactation in relation to the first lactation cows,head SCC increased over 3 times,which indicates the increase of the chance of the cows to be susceptible to intramammary infections.All data showed a gradual increase in depth length,width and volume of the udder as the number of parity increases.The differences observed in udder morphometry in different parities were found significant(p<0.05)to highly significant(p<0.01).The values of the coefficients of correlation for the analyzed udder and teat conformation traits and SCC in milk,were statistically varied and ranged from-0.32 to+0.28.Accordingly,the udder and teat morphometry characteristics such as distance from rear are fore teat-tip to the floor,udder depth,volume,teat diameter,can be said to have some degree of association with the udder health in Holstein Friesian cows evaluated in this study.Hence their inclusion in breeding program as indicator traits may help reduce the incidence of intramammary infections. 展开更多
关键词 somatic cell UDDER MILK
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Blood neutrophil extracellular traps:a novel target for the assessment of mammary health in transition dairy cows
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作者 Luyi Jiang Huizeng Sun +3 位作者 Fengfei Gu Jin He Fengqi Zhao Jianxin Liu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1068-1079,共12页
Background:Mammary health is important for transition dairy cows and has been well recognized to exert decisive effects on animal welfare.However,the factors influencing mammary health are still unclear.Differential s... Background:Mammary health is important for transition dairy cows and has been well recognized to exert decisive effects on animal welfare.However,the factors influencing mammary health are still unclear.Differential somatic cell count(DSCC)could reflect the mastitis risk since it is the percentage of neutrophils plus lymphocytes in total somatic cells and could be reflective of mammary health of dairy cows.This work aimed to investigate the assessment and prognosis of the health of transition cows based on blood neutrophil extracellular traps(NETs).Results:Eighty-four transition Holstein dairy cows were selected.The serum was sampled in all the animals at week 1 pre-and postpartum,and milk was sampled at week 1 postpartum.Based on the DSCC in milk at week 1,cows with lower(7.4%±4.07%,n=15)and higher(83.3%±1.21%,n=15)DSCCs were selected.High DSCC cows had higher levels of red blood cell counts(P<0.05),hemoglobin(P=0.07),and hematocrit(P=0.05),higher concentrations of serum oxidative variables[reactive oxygen species(P<0.05),malondialdehyde(P<0.05),protein carbonyl(P<0.05),and 8-hydroxy-2-deoxyguanosine(P=0.07)],higher levels of serum and milk NETs(P<0.05)and blood-milk barrier indicators,including serumβ-casein(P=0.05)and milk immunoglobulin G2(P=0.09),than those of low DSCC cows.In addition,lower concentrations of serum nutrient metabolites(cholesterol and albumin)(P<0.05)and a lower level of serum deoxyribonuclease I(P=0.09)were observed in high DSCC cows than in low DSCC cows.Among the assessments performed using levels of the three prepartum serum parameters(NETs,deoxyribonuclease I andβ-casein),the area under the curve(0.973)of NETs was the highest.In addition,the sensitivity(1.00)and specificity(0.93)were observed for the discrimination of these cows using NETs levels with a critical value of 32.2 ng/mL(P<0.05).Conclusions:The formation of NETs in blood in transition dairy cows may damage the integrity of the blood-milk barrier and thereby increase the risk for mastitis in postpartum cows. 展开更多
关键词 Blood-milk barrier Differential somatic cell count Mastitis risk Neutrophil extracellular traps
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Effect of Bacterial Content and Somatic Cell Count on Sheep Milk Quality in Kosovo
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作者 Hysen Bytyqi Hajrip Mehmeti +2 位作者 Idriz Vehapi Fillojeta Rrustemaj Ibrahim Mehmeti 《Food and Nutrition Sciences》 2013年第4期414-419,共6页
The main objective of this study was to analyze the effect of bacterial content (CFU) and somatic cell count (SCC) in milk quality in sheep (Ovis aries) farms according to the existing standards for fresh milk quality... The main objective of this study was to analyze the effect of bacterial content (CFU) and somatic cell count (SCC) in milk quality in sheep (Ovis aries) farms according to the existing standards for fresh milk quality in Kosovo. A total of 2256 milk test day records from 379 Bardhoka (BAR), Sharri sheep (SHA), Kosovo sheep (KOS) and Balusha (BAL) ewes in eight herds across the country were collected and analyzed through a period April-October 2010. The general linear model and Duncan’s test were used to analyze the effect of different variables on presence of CFU and SCC in fresh milk. The effect of all variables was considered as a fixed. The overall results show that farm (P 0422), respectively, had a significant effect on presence of SCC. For CFU farm (P 0422) and breed (P 1211.17 to 6425.76 CFU/mL and 846.07 to 2043.15 SCC/mL milk, respectively. Although the rate of fresh milk contamination with SCC tends to be relatively low compare with CFU, by all means both variables should not be underestimated bearing in mind that a high rate of them on fresh milk are negatively correlated with farmer’s profit, consumer food safety and overall animal health. 展开更多
关键词 Fresh Milk Bacteria Content somatic cell Milk Quality Standards
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Impact of Bacterial and Somatic Cells Content on Quality Fresh Milk in Small-Scale Dairy Farms in Kosovo
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作者 Hysen Bytyqi Idriz Vehapi +3 位作者 Sejdi Rexhepi Mentor Thaqi Dritan Sallahi Ibrahim Mehmeti 《Food and Nutrition Sciences》 2013年第10期1014-1020,共7页
The basic goal of this research was to determine the impact of the presence of bacterial (CFU) and somatic cells count content (SCC) in quality of fresh milk in some small cattle farms in Kosovo. The survey was based ... The basic goal of this research was to determine the impact of the presence of bacterial (CFU) and somatic cells count content (SCC) in quality of fresh milk in some small cattle farms in Kosovo. The survey was based on existing standards for milk quality in Kosovo placed under administrative guidance MA-no. 20/2006. The study was based on fresh milk analysis of 150 farms performed during the period September-December 2012, which was obtained in 9 different localities (collection points) of the Kosovo. Our study reveals that CFU and SCC in fresh milk were significantly affected by a number of factors, as: sampling period (repetition), locality, breed, and time of sampling (evening or/and morning). According to the results for CFU and SCC, there were big differences between the farms (milk collection points) included in the study (P < 0.0403) and (P < 0.0293). The results show that small size breed like Busha and its crosses tend to be less exposed to SCC/mL in milk (72.840) and (293.592), compared to Black Holstein (613.462), Simmental (521.519) and Brown Swiss (418.44). Milk produced in evening tended to be of better quality (259.854 CFU/mL) compared to the one from morning milking (576.689 CFU/mL). Fresh milk quality analyzed in the third repetition was better for about 33.3% compared with the repletion first. For CFU and SCC, the analyses show that about 74.7% and 64.7% of milk produced belongs to extra quality, while lower quality of milk of category three is 12.0% and 23.3%, respectively. Considering that about 85% of milk produced in Kosovo comes from small-scale dairy farms, the current study sets out that small-scale milk production system cannot be neglected by interest parties in dairy sector and needs permanent following up and improvement. 展开更多
关键词 Fresh Milk Bacteria Content somatic cell Milk Quality Standards
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China Succeeded in Somatic Cell Cloning
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作者 Song Jianlan 《Bulletin of the Chinese Academy of Sciences》 2002年第1期5-6,共2页
  Chinese scientists have succeeded in cloning a colony of cattle from fully differentiated somatic cells. The news was announced jointly by the Chinese Academy of Sciences (CAS), National Natural Science Foundation...   Chinese scientists have succeeded in cloning a colony of cattle from fully differentiated somatic cells. The news was announced jointly by the Chinese Academy of Sciences (CAS), National Natural Science Foundation of China (NSFC) and the government of Shandong Province at a press conference held on March 7, 2002.…… 展开更多
关键词 NSFC cell China Succeeded in somatic cell Cloning
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