Transcriptome‑wide mapping of milk somatic cells upon subclinical mastitis infection in dairy cattle

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.

PiggyBac Transposon Mediated Efficient eGFP Expression in Porcine Somatic Cells and Cloned Embryos

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.

Impact of Bacterial and Somatic Cells Content on Quality Fresh Milk in Small-Scale Dairy Farms in Kosovo

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.

Generation of cloned calves from different types of somatic cells

Six types of bovine somatic cell lines, including a granulosa cell line of Chinese red-breed yellow cattle (YGR), a granulosa cell line of Holstein cow (HGR), two skin fibroblast cell lines of two adult Holstein cows respectively (AFB1 and AFB2), a skin fibroblast cell line (FFB) and an oviduct epithelial cell line (FOV) of a Holstein fetus, were established. Somatic cell nu-clear transfer (SCNT) was carried out using these cells as nuclei donor, and a total of 12 healthy calves were cloned. The effects of different types of donor cells on developmental potential of bovine SCNT embryos were investigated. (i) There was no significant difference in development rates to the blastocyst stage for SCNT embryos from YGR and HGR (33.2% and 35.1%, respec-tively). Pregnancy rates of them were 33.3% and 30.2%, respectively; and birth rates were 16.7% and 11.6%, respectively. (ii) Development rates to the blastocyst stage for SCNT embryos from diffetent individuals (AFB1 and AFB2) differed significantly (27.9% and 39.4%, respectively, P <0.05). Pregnancy rates of them were 36.2% and 36.4%, respectively; and birth rates were 14.9 % and 27.3%, respectively. (iii) There was significant difference in development rates to the blastocyst stage for SCNT embryos from FFB and FOV of the same fetus (37.9% and 41.5%, respectively, P < 0.05). Pregnancy rates of them were 45.7% and 24.1%, respectively; and birth rates were 22.9 % and 10.3%, respectively. Finally, developmental potential of bovine SCNT embryos from all four types of somatic cells from Holstein cows (HGR, AFB, FFB and FOV) were compared. For in vitro development stage, development rates to the blastocyst stage for SCNT embryos from HGR, AFB, FFB and FOV were 35.1%A, 29.4%B, 37.9%A and 41.5%C, respectively (PABC<0.05); for in vivo development stage, pregnancy rates of them were 30.2%, 36.2%, 45.7% and 24.1%, respectively; and birth rates of them were 11.6%, 17.2%, 22.9% and 10.3% respec-tively.

Exploring the developmental potential of adult mammalian somatic cells

In the traditional views on developmental biology, the process of a mammal from a zygote to. an adult individual follows continuous changes of space and time environments and is the result of different expressions of target genes. It has long been known that this process is irreversible and the terminal differentiated adult cells, such as cardiac myocytes and neurons, will not divide and differentiate. But recent reports on the two hottest fields - cloning medicine and stem cell biology doubted these concepts. This may lead to a further understanding of the potentiality of mammal development and may provide great chances for commercial and clinical practice.

Reprogramming somatic cells to cells with neuronal characteristics by defined medium both in vitro and in vivo

Background:Currently,direct conversion from somatic cells to neurons requires virus-mediated delivery of at least one transcriptional factor or a combination of several small-molecule compounds.Delivery of transcriptional factors may affect genome stability,while small-molecule compounds may require more evaluations when applied in vivo.Thus,a defined medium with only conventional growth factors or additives for cell culture is desirable for inducing neuronal trans-differentiation.Results:Here,we report that a defined medium(5C)consisting of basic fibroblast growth factor(bFGF),N2 supplement,leukemia inhibitory factor,vitamin C(Vc),andβ-mercaptoethanol(βMe)induces the direct conversion of somatic cells to cells with neuronal characteristics.Application of 5C medium converted mouse embryonic fibroblasts(MEFs)into TuJ+neuronal-like cells,which were capable of survival after being transplanted into the mouse brain.The same 5C medium could convert primary rat astrocytes into neuronal-like cells with mature electrophysiology characteristics in vitro and facilitated the recovery of brain injury,possibly by inducing similar conversions,when infused into the mouse brain in vivo.Crucially,5C medium could also induce neuronal characteristics in several human cell types.Conclusions:In summary,this 5C medium not only provides a means to derive cells with neuronal characteristics without viral transfection in vitro but might also be useful to produce neurons in vivo for neurodegenerative disease treatment.

Variations in mesenchymal-epithelial transition-related transcription factors during reprogramming of somatic cells from different germ layers into iPSCs

Introducing a combination of transcription factors such as Oct4,Sox2,Klf4 and c-Myc（OSKM）enables reprogramming which converts somatic cells into induced pluripotent stem cells（i PSCs）（Takahashi and Yamanaka,2006）.i PSCs play an important role in clinical and regenerative medicine because they can be utilized to model a specific disease or differentiate into functional cells for transplantation.Enhancing the efficiency of induction and improving the qualities of iPSCs are constant themes in this field.

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

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.

Udder Health Status of First Parity Dairy Cows in Early-Lactation Based on Somatic Cell Count Categories

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.

Single‑cell sequencing reveals the reproductive variations between primiparous and multiparous Hu ewes

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.

Relationship of Somatic Cell Count with Milk Yield and Composition in Chinese Holstein Population

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.

Nucleus Transfer Efficiency of Ear Fibroblast Cells Isolated from Bama Miniature Pigs at Various Ages

Summary： Somatic cell nucleus transfer （SCNT） has been considered the most effective method for conserving endangered animals and expanding the quantity of adult animal models. Bama miniature pigs are genetically stable and share similar biological features to humans. These pigs have been used to establish animal models for human diseases, and for many other applications. However, there is a pan- city of studies on the effect of ear fibroblasts derived from different age of adult Bama miniature pigs on nucleus transfer （NT）. The present study examined the NT efficiency of ear fibroblasts from fetal, new- born, 1-, 2-, 4-, 6-, 12-month-old miniature pigs by using trypan blue staining, flow cytometry and NT technique, etc., and the cell biological function and SCNT efficiency were compared between groups. The results showed that ear fibroblasts grew well after passage in each group. Spindle-shaped cells ini- tially predominated, and gradually declined with increase of culture time and replaced by polygonal cells. Irregular cell growth occurred in the 2-month-old group and the elder groups. The growth curves of the ear fibroblasts were ＂S-shaped＂ in different age groups. The cell proliferation of postnatal ear fi- broblasts, especially those from 2-, 4-, 6-, 12-month-old miniature pigs was significantly different from that of fetus ear fibroblasts （P〈0.05 or P〈0.01）. Two-month- and 4-month-old ear fibroblasts had a sig- nificantly higher proportion of G1 stage cells （85% to 91%） than those at 6 and 12 months （66% to 74%, P〈0.01）. The blastocyst rate of reconstructed embryos originating from newborn, 1-, 2-, 4-month-old donor pigs was 6.06% to 7.69% with no significant difference from that in fetus fibroblast group （8.06%）. It was concluded that 〈4-month-old adult Bama miniature pigs represent a better donor cell resource than elder pigs.

Effect of Rare Earth Elements on the Induction Frequency of the Somatic Cell Embryo in The Fruit of Chinese Wolfoerry

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%.

Genetic parameters for somatic cell score and production traits in the fi rst three lactations of Chinese Holstein cows

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.

Mapping of Microsatellite SW943 to Porcine Chromosome 12p11-(2/3p13) Using Primed in situ Synthesis and Somatic Cell Hybrid Panel

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.

Evolutionary model of brain tumor circulating cells: Cellular galaxy

BACKGROUND Although circulating tumor cells(CTCs)have been the focus of consideration for a decade,a categorized cell-based diagnostic strategy is unavailable.The personalized management and complementary/analytical-strategy of data require an alphabetic guide.Therefore,we aimed to determine the behavior of CTCs in tumor and blood in order to provide the hypothetical-based agenda in the brain neoplasms.Exploring the protein expression(PE)using a single cell-based method would clarify the heterogeneity and diversity in tumor and blood,which are key events in the evolution in brain tumors.In fact,heterogeneity,diversity,and evolution are required for cancer initiation and progression.AIM To explore CTCs in brain tumors and blood cells and to assay intensity of PE through personalized insight.METHODS The focal population included 14 patients with meningioma,and four patients with metastatic brain tumors(T).PE was assayed by immunofluorescence in tumors cells and CTCs in 18 patients with brain tumors.Ratio test was applied between the T cells and CTCs in tumor tissue and in vascular system.T/CTC ratio-based classification of PE in macrophage chemoattractant chemokine ligand 2(CCL2),vascular endothelial growth factor(VEGF),epidermal growth factor(EGF),CD133,cyclin E,neurofilament marker,cytokeratin 19,and leukocyte common antigen(CD45)were investigated.RESULTS Total analyzed cells ranged between 10794-92283 for tumor cells and between 117-2870 for CTCs.Characteristics of histopathologic and status of an ataxiatelangiectasia mutated polymorphism(D1853N)in 18 patients affected with brain tumors were also provided.The course of evolution and metastatic event relied on the elevated protein expression in CTCs,which could be considered as a prognostic value.Diverse protein expression of the migrated cells into the blood stream and the tumor was indicative of the occurrence of evolution.Besides,the harmonic co-expression between CCL2/EGF and CCL2/VEGF could facilitate the tumor progression including the metastatic event.Expression of these proteins in the migrated vasculature and into the buccal tissue offered a non-invasive followup detection in neoplastic disorders.PE-exploration of neurofilament marker/CD133/VEGF of the CTCs in meningioma and cytokeratin 19/CD45/cyclin E in the patients with metastatic brain tumor would clarify the tumor biology of the brain neoplastic disorders.CONCLUSION The alphabetical base of the evolutionary mechanisms relies on dual-,triple-,and multi-models with diverse intensity of expression.In fact,cross-talk between initiative and the complementary channels defines the evolutionary insight in cancer.A diverse-model of protein expression,including low,medium,and high intensity,is the key requirement for the completed model.The cluster of cells with diverse expression and remarkable co-expression between CCL2/EGF/VEGF and NM/CD133/VEGF in CTCs may be indicative of probable invasiveness of the tumor.Furthermore,the mode of cytokeratin-19+/CD45-can be traced in the metastatic patients.

Somatic Cell Count in Relation to Udder and Morphometry in Holstein Friesian Dairy Cows

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.

Effect of Bacterial Content and Somatic Cell Count on Sheep Milk Quality in Kosovo

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.

China Succeeded in Somatic Cell Cloning

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.……

Methylome and transcriptome data integration reveals potential roles of DNA methylation and candidate biomarkers of cow Streptococcus uberis subclinical mastitis

Background:Mastitis caused by different pathogens including Streptococcus uberis(S.uberis)is responsible for huge economic losses to the dairy industry.In order to investigate the potential genetic and epigenetic regulatory mecha‑nisms of subclinical mastitis due to S.uberis,the DNA methylome(whole genome DNA methylation sequencing)and transcriptome(RNA sequencing)of milk somatic cells from cows with naturally occurring S.uberis subclinical mastitis and healthy control cows(n=3/group)were studied.Results:Globally,the DNA methylation levels of CpG sites were low in the promoters and first exons but high in inner exons and introns.The DNA methylation levels at the promoter,first exon and first intron regions were nega‑tively correlated with the expression level of genes at a whole‑genome‑wide scale.In general,DNA methylation level was lower in S.uberis‑positive group(SUG)than in the control group(CTG).A total of 174,342 differentially methylated cytosines(DMCs)(FDR<0.05)were identified between SUG and CTG,including 132,237,7412 and 34,693 DMCs in the context of CpG,CHG and CHH(H=A or T or C),respectively.Besides,101,612 methylation haplotype blocks(MHBs)were identified,including 451 MHBs that were significantly different(dMHB)between the two groups.A total of 2130 differentially expressed(DE)genes(1378 with up‑regulated and 752 with down‑regulated expression)were found in SUG.Integration of methylome and transcriptome data with MethGET program revealed 1623 genes with signifi‑cant changes in their methylation levels and/or gene expression changes(MetGDE genes,MethGET P‑value<0.001).Functional enrichment of genes harboring≥15 DMCs,DE genes and MetGDE genes suggest significant involvement of DNA methylation changes in the regulation of the host immune response to S.uberis infection,especially cytokine activities.Furthermore,discriminant correlation analysis with DIABLO method identified 26 candidate biomarkers,including 6 DE genes,15 CpG‑DMCs and 5 dMHBs that discriminated between SUG and CTG.Conclusion:The integration of methylome and transcriptome of milk somatic cells suggests the possible involve‑ment of DNA methylation changes in the regulation of the host immune response to subclinical mastitis due to S.uberis.The presented genetic and epigenetic biomarkers could contribute to the design of management strategies of subclinical mastitis and breeding for mastitis resistance.