Background

Lipid is one of the main nutrients in chicken yolk,and has an important role in fueling the embryonic development of chickens[1,2].When the glucose is fully consumed,lipids in the yolk are used predominantly at early embryonic developmental stages[3],and more than 90%of the embryo’s energy comes from fatty acid oxidation[4].Differences in the usage of lipids from the yolk sac influence the different growth patterns seen in chicken embryogenesis[5].

卢春泉坦承，民事诉讼将经历一个漫长的过程。但作为一个估值上百亿、一度接受上市辅导的公司，银隆不可能坐等诉讼结果，接下来如何发展才是重要的问题。

Two mechanisms exist for consuming lipids from the yolk sac:absorption through blood circulation or absorption through the small intestine.A total of 80%of the lipids in the yolk sac are consumed by embryo growth by the final week of the prehatching stage[4,6],and the remainder is transported into the embryonic abdominal cavity and deposited into nearby tissues after hatching[7,8].This results in a rapid increase in the content of intramuscular fat(IMF),which coexists with muscle tissue in breast and thigh.

A few studies on chicken lipid metabolism before and after hatching have been reported[9,10],but there is still a lack of systematic research on the molecular regulation of IMF deposition from the yolk sac at hatching.In this study,with the aim of identifying global differentially expressed genes(DEGs)and pathways related to lipid metabolism in chicken breast associated with fast-and slow-growing breeds at hatching,a comparative analysis of the gene expression levels between fast-(Arbor Acres,AA;a commercial fast-growing broiler)and slow-growing chickens(Beijing-You,BJY;aslow-growingChinese breed)was performed using microarray technology.

Methods

Animals and sample collection

The expression levels of 10 genes(among 44 genes)related to fatty acid degradation(ACAT1,CPT1A,CPT2,DAK,ACOX2,ACOX3)and glycometabolism(APOO,FUT9,GCNT1,B4GALT3)were significantly lower(P＜0.05 or P＜0.01)in AA than in BJY chickens.Verification of these microarray results was obtained by qPCR,which showed that the expression of these 10 genes,related to fatty acid degradation(ACAT1,CPT1A,CPT2,DAK,ACOX2,ACOX3)(Fig.4a)and glycometabolism(APOO,FUT9,GCNT1,B4GALT3)(Fig.4b),was significantly lower(P＜0.05 or P＜0.01)in AA chickens than in BJYchickens.

随着两化融合的持续推进，工业企业不断建设形成互联网时代的可持续竞争能力[4]，两化融合在激发创新活力、提高生产资源利用率、增强产品和服务供给能力、推动整体提质降本增效方面的作用逐步显现[5]。经济效益方面，两化融合能够有效提高企业创新投入[6]、降低产品边际成本[7]、支撑市场差异化需求响应[8]；社会效益方面，两化融合能够激发更广泛的技术创新，推动实现能源管理和环保管理[9-11]。因此，本文拟探索两化融合对提升企业价值创造能力的绩效情况，以上市企业为对象，提出假设H1。

After birds had been weighed and their live weight had been recorded,they were sacrificed and the pectoralis major and yolk sac were excised.The pectoralis major samples were stored at-80 °C or-20 °C for RNA isolation and the measurement of IMF content.The yolk sac samples were stored at-20°C for the measurement of total yolk energy content(TYE).

Measurement of biochemical indexes

TYE was determined with a Parr 1281 bomb calorimeter(Parr Instrument Co.,Moline,IL,USA).IMF content in pectoralis major was measured by the Soxhlet method[11],using anhydrous ether as the solvent,and is expressed as a percentage of dry tissue weight.

Total RNA preparation,microarray hybridization,and analysis of DEGs

评价是以小组为单位，进行捆绑式评价，旨在强化学生的团队互助意识，促使学生在小组内自觉进行互助行为，最终提高小组整体水平。评价方式在传统基础上可利用现代教育技术手段，借助于如“班级优化大师”一类的教学管理软件，根据小学生年龄特点，可以是“星星评价”，“QQ”等级评价或者是“红黄绿”警示评价，这样可以大大增强学生参与合作的兴趣和小组互助的协同意识。一般情况下可以以月为单位进行月总结，期末时再进行总评比。

Total RNA samples from six AA and six BJY chickens were isolated individually and pooled for microarray analysis with equal amounts(1 μg)from every sample.Microarray hybridization was performed by Shanghai Biotechnology Corporation(Shanghai,China)using an Agilent Chicken Gene microarray(ID:015068).Array scanning and data extraction were accomplished following standard protocols.The normalized fluorescence intensity values from each dye-swapped experiment were averaged separately,after which averaged sample and reference fluorescence values were log2-transformed for each probe.The expression value of each probe set was normalized and calibrated using the RMA method.DEGs were screened and genes were considered to be differentially expressed only when the relative abundance fold change between the two breeds exceeded 2.

Quantitative real-time PCR(qPCR)

Individual RNA samples from all chickens were used.All PCR primers were designed at or just outside exon/exon junctions to avoid the amplification of residual genomic DNA,and specificity was determined using BLASTN(Table 1).

1.深港两市的收益率在“深港通”开通之前互不为格兰杰因果关系，两地市场对信息冲击的响应曲线具有短记忆性；在“深港通”启动之后格兰杰因果关系具有非对称性，主要是深市向港市的单向格兰杰因果关系，两地市场对信息冲击的响应具有持久性，且深市起主要引导作用。

qPCR analysis was performed after a reverse transcription reaction,as previously described[12].cDNA was prepared with 2.0 μg of total RNA of each sample,in accordance with the manufacturer’s instructions.For qPCR,each PCR mixture with a volume of 25 μL contained 12.5 μL of 2 × iQ™SYBR Green Supermix,0.5 μL(10 mmol/L)of each primer,and 1 μL of cDNA.Mixtures were incubated in an iCycler iQ Real-time Detection system(Bio-Rad,Hercules,CA,USA)programmed to conduct 40 cycles(95 °C for 15 s and 65 °C for 35 s).Quantitation of the transcripts was performed using a standard curve with 10-fold serial dilutions of cDNA.A melting curve was constructed to ensure that only a single PCR product was amplified.Samples were assayed in triplicate with standard deviations of threshold cycle(CT)values not exceeding 0.5,and each experiment was repeated at least twice.Negative(without template)control reactions were performed for each sample.

Gene ontology(GO)enrichment analysis and visualization

GO enrichment analysis was performed to identify the gene function classes and categories corresponding to the DEGs using the GOEAST software toolkit.The significance level for GO term enrichment was set at a false discovery rate(FDR)adjusted to less than 0.5 and a P-value of less than 0.05,by the Yekutieli method.

Kyoto encyclopedia of genes and genomes(KEGG)pathway analysis

国家税务总局于2005年印发了《纳税评估管理办法(试行)》，该文首次对纳税评估工作给出明确的定义：纳税评估是指税务机关运用数据信息对比分析的方法，对纳税人和扣缴义务人纳税申报情况的真实性和准确性作出定性和定量的判断，并采取进一步征管措施的管理行为。随着时间推移，税收征管改革不断深化，纳税评估工作被赋予了新的内涵，综合体现服务行为与行政执法行为。作为税务机关对纳税人自我申报的义务履行情况进行检查、审核的执法活动，纳税评估具有其他管理手段无法替代的优点。

Statistical analyses

3.加强中层干部打造高绩效团队的能力。新形势下，一个部门能否出色完成任务，只靠一名优秀的中层干部远远不够，还要有一支高效、能打赢仗的团队。因此，随着竞争的日益激烈，任何一个部门都更加强调发挥团队精神。而能否打造高绩效的团队，对于中层干部来说，也就显得格外重要。

Additional file 3:A total of 44 known DEGs related to lipid metabolism in AA and BJY chickens.(XLS 59 kb)

Table 1　The specific primers for qPCR in this study

Gene　Sequence Product size　Accession NO.THRSP　F:5′-ATCAAGCCCGTGGTGGAGC-3′R:5′-CTTTGGTGTTTTTGGTGAGGTCG-3’ACACA　F:5’-AACCTGCTAAACCCCTGG-3′R:5′-AGTCCCAAATCCGAAAGG-3’ACSS1　F:5’-TGGGAGATGTTACCACAC-3′R:5′-GCAGAATACACCAAGAGAG-3’PPARG　F:5’-TAAAGTCCTTCCCGCTGACCAAA-3′R:5′-AAATTCTGTAATCTCCTGCACTGCCTC-3’LPL　F:5’-AGGAGAAGAGGCAGCAATA-3′R:5′-AAAGCCAGCAGCAGATAAG-3’FABP4　F:5’-GGGGTTTGCTACCAGGAAGATG-3′R:5′-CATTCCACCAGCAGGTTCCC-3’RBP7　F:5’-TTCCATCCATACCACAAGCACA-3′R:5′-AGTGAGTCCAGCCCCTGTTCTT-3’DGAT2　F:5’-AATGGGTCCTCACGTTCC-3′R:5′-TGGTGGTCAGCAGGTTGT-3’GK　F:5’-TATGGCTGCTACTTTGTGC-3′R:5′-GTATCCCGCAGTCCTTGT-3’ACAT1　F:5’-CTCCAGCAAGACAGGCAGT-3′R:5′-CACCAGCAACCATTACATCC-3’ACOX2　F:5’-TATGTAAGGCGTGGGTCA-3′R:5′-TATGTAAGGCGTGGGTCA-3’ACOX3　F:5’-ACATCTGGCTGTGCTCTATC-3′R:5′-ACTCCCCGCTAGCTTTAC-3’CPT1A　F:5’-AGACGGACACTGCAAAGGAG-3′R:5′-AGCCCCTTCCCAAAAACA-3’CPT2　F:5’-GGGTCGTGTTGGGCTGTT-3′R:5′-AAAGAGGTTTCTGGGCGTTC-3’DAK　F:5’-AGAGGAGGAAGGAATTGACCTC-3′R:5′-GTCGAAGACCACATGGCTGT-3’APOO　F:5’-CTGCCTTCTGCCTCAGGAAA-3′R:5′-CAATGCTGATCCTGCAACGG-3’FUT9　F:5’-TGAAATGTGTAGCTGCGTGGA-3′R:5′-AGACGTCTCCGAATTGCTTGT-3’GCNT1　F:5’-ACCAAGATACTGGAGGGCGA-3′R:5′-CTCACTGCTGAGAGGTTCCA-3’B4GALT3　F:5’-TCCTCCTGCACGATGTGAAC-3′R:5′-TCGCCCCAGTATGTGTTTGG-3’184 bp　NM_213577 175 bp　NM_205505 181 bp　XM_415011 230 bp　NM_001001460 222 bp　AB016987 276 bp　NM_204290 179 bp　XM_417606 237 bp　XM_419374 187 bp　XM_416788 150 bp　XM_417162 198 bp　XM_414406 179 bp　XM_420814 174 bp　NM_001012898 168 bp　XM_001234342 272 bp　NM_001079500 162 bp　XM_015272548 141 bp　NM_001079502 174 bp　XM_003643022 202 bp　XM_416564

Results

Fast-growing chickens had higher levels of TYE and fat deposition at hatching than did slow-growing chickens

Data on live weight(LW),IMF content,absolute TYE amount,and LW-specific TYE amount(u-TYE)in the two breeds are plotted in Fig.1a-d.The content of IMF in the pectoralis major of AA chickens(2.57%)was significantly higher(P＜0.05)than that(2.14%)of BJY chickens.Similarly,the LW,TYE,and LW-specific u-TYE amounts were also significantly higher(P＜0.01,

P＜0.01,P＜0.05)in AA chickens(40.46 g,57.92 kJ,1.43 kJ/g)than in BJY ones(31.39 g,33.58 kJ,1.07 kJ/g).As shown in Fig.2a,the correlation between IMF and u-TYE was r=0.9047(P＜0.01).There was more fat deposition in the pectoralis major of AA chickens than in BJY chickens on the day of hatching,which was suggested to have occurred because more energy had been supplied from the yolk sac in the former group.

Higher expression of genes related to lipid biosynthesis in muscle of fast-growing than slow-growing chickens

Fig.1　Summary of TYE,u-TYE,and IMF content in AA and BJY chickens on the day of hatching.Means within the same panel indicate significant differences between the two breeds(P＜0.01 or P＜0.05).Data are presented as mean±SEM(n=6)

Using an Agilent Chicken Gene microarray,a total of 787 known DEGs,364 upregulated and 423 downregulated ones,were found in the pectoralis major of AA chickens at hatching,compared with their levels in BJY chickens(Additional file 1).Based on these 787 known DEGs,GO analysis was performed and GO terms enriched(P＜0.05)forbiologicalprocesseswere selected,as presented in Additional file 2.Based on GO-term analysis,44 known DEGs related to lipid metabolism were screened.Compared with their levels in BJY chicken,25 upregulated and 19 downregulated DEGs related to lipid metabolism were identified in AA chickens(Additional file 3),which are involved in many biological pathways:fatty acid biosynthesis,preadipocyte differentiation,triglyceride biosynthesis,and fatty acid degradation.

From these 44 DEGs,15 representative ones were selected to validate the microarray results by qPCR,and the correlation of the fold changes of the two breeds between these two sets of results(Fig.2b)was r=0.9797(P＜0.01),indicating extremely strong correspondence for all 15 genes.It was also found that the relative expression of 9 of the 15 genes related to fatty acid biosynthesis(THRSP,ACACA,ACSS1)(Fig.3a),preadipocyte differentiation(PPARG,LPL,FABP4,RBP7)(Fig.3b),and triglyceride biosynthesis(DGAT2,GK)(Fig.3c)was significantly upregulated(P＜0.05 or P＜0.01)in AA compared with the level in BJY chickens,consistent with the differences in lipid deposition.These results suggested that these genes are responsible for the greater IMF deposition in fast-growing chickens than in slow-growing ones.

Lower expression of genes related to fatty acid degradation and glycometabolism in fast-growing than in slow-growing chickens

Fig.2　The correlation analysis by Spearman rank correlation in fast-(AA)and slow-growing(BJY)chickens.The high correlation coefficient(r=0.9047)indicates that the IMF content correlated strongly with u-TYE in the two breeds(n=12).The very high correlation coefficient(r=0.9797)indicates that the qPCR fold changes of the two breeds correlated strongly with the microarray data(n=15)

Six AA and six BJY chickens(half male and half female)on the day of hatching were used in this study.Individuals within each breed had the same genetic background.Animal experiments were approved by the Science Research Department(in charge of animal welfare issues)at the Institute of Animal Sciences,Chinese Academy of Agricultural Sciences(CAAS),Beijing,China.

The difference in expression level of these genes between the two breeds was consistent with these genes possibly contributing to greater deposition of IMF in the pectoralis major of AA chickens than that in BJYchickens at hatching.

PPAR and other related signaling pathways regulate differences of expression in related DEGs between the two breeds at birth

Fig.3　The expression levels of DEGs related to lipid biosynthesis determined by qPCR in fast-(AA)and slow-growing(BJY)chickens.These genes are all involved in fatty acid biosynthesis,preadipocyte differentiation,or triglyceride biosynthesis.All of these DEGs were significantly(P＜0.01 or P＜0.05)more highly expressed in AA chickens than in BJY chickens.Data are presented as mean±SEM(n=6)

A KEGG pathway analysis was performed on the 787 known DEGs to investigate the regulation of lipid metabolism in the pectoralis major at hatching.Seventeen KEGG pathways were identified in AA and BJY chickens(Additional file 4).Based on the 44 known DEGs related to lipid metabolism,another pathway analysis was performed and 7 KEGG pathways were identified in the two breeds(Additional file 5);then,five common enriched pathways(PPAR signaling,fatty acid metabolism,Hedgehog signaling,TGF-beta　signaling,　and　cytokine-cytokine　receptor interactions)were identified by the two KEGG pathway analysis methods.

Discussion

Fig.4　The expression levels of DEGs related to fatty acid degradation or glycometabolism determined by qPCR in fast-(AA)and slow-growing(BJY)chickens.These genes are all involved in fatty acid degradation or glycometabolism.Each of these DEGs was significantly(P＜0.01 or P＜0.05)downregulated in AA chickens compared with its level in BJY chickens.Data are presented as mean±SEM(n=6)

Lipid is an essential energy source and cell membrane component in animals and,in chickens,is mainly deposited in abdominal,subcutaneous,and muscle adipose tissues.Although global gene expression research has been performed on abdominal adipose tissues[15-17],systematic research on the molecular regulation of IMF deposition in chicken pectoralis major at hatching has not.In this study,gene expression profiling was used to identify global DEGs and the pathways related to lipid metabolism in the breast muscle of fast-and slow-growing chickens at hatching.

cDNA array analysis

Acknowledgements

DEGs related to lipid metabolism in chicken pectoralis major at hatching

The yolk is the sole source of energy during the embryonic stages and at hatching.The remaining yolk energy supply upon hatching is absorbed and transported to tissues for deposition.The TYE and deposition of IMF in the pectoralis major in AA chickens were significantly higher(P＜0.01,P＜0.05)than those in BJY chickens at hatching,and were correlated in both breeds.

人事档案管理需要完善健全的制度，只有这样才能综合性提升其管理水平，才能切实提升人事档案管理的成效。当前，大部分事业单位人事档案管理工作中，缺乏科学完善的制度，缺乏全面系统的体系，管理不够规范。

These DEGs include Spot 14(encoded by THRSP)[19,20],ACACA[21],and ACSS1[22,23]play important roles in lipid metabolism by accelerating fatty acid biosynthesis.PPARG,RBP7,LPL,and FABP4,which positively regulate the process of preadipocyte differentiation[24,25].Similarly,DGAT2 and GK promote esterification[26,27].All of these nine genes had significantly higher expression in the pectoralis major of AA chickens than in BJY chickens at hatching.Conversely,the expression of several genes was significantly lower in AA chickens than in BJY chickens.Among these,ACAT1,ACOX2,ACOX3,CPT1A,CPT2,and DAK positively regulate different steps of fatty acid oxidation[28-31],and FUT9,GCNT1,APOO,and B4GALT3 all positively regulate energy use in maintaining metabolic balance between carbohydrates and lipids[32-36].

All of these differences in gene expression were either positively or negatively correlated with IMF content.This suggests that these genes play a role in regulating IMF deposition in the pectoralis major of chickens at hatching.

Fig.5　Lipid metabolism regulatory network proposed for the breast of female chickens at hatching,based on significant DEGs and KEGG pathway analysis.The network involves Hedgehog,TGF-beta,and cytokine-cytokine receptor interaction signaling pathways,through SHH,BMP,and LEPR molecular interactions.These three pathways potentially regulate lipid metabolism via the PPAR signaling pathway

Signaling pathways related to lipid metabolism in breast muscle at hatching

GO-term analysis was used to explore the function of the DEGs,and KEGG pathway analysis was used to explore the regulatory networks underlying IMF content.As expected,several well-known pathways relating to lipid metabolism were identified,including PPAR signaling,fatty acid metabolism,Hedgehog,TGF-beta,and cytokine-cytokine receptor interactions[37-40].

KEGG pathway[13,14]information was also used in the analysis.A ProbeName for each category was first mapped to an NCBI Entrez gene ID according to the Agilent Chicken microarray annotation file,and then each was mapped to an appropriate KEGG gene ID according to the KEGG gene cross-reference file.Pathways that were significantly enriched with DEGs were identified using a hypergeometric test from the R package(P＜0.1,FDR-adjusted).Pathways with fewer than three known chicken genes were discarded.

The PPAR signaling pathway is known to play an important role in regulating lipid metabolism[40,41].Many DEGs identified here are involved in PPAR signaling pathways,including ACOX2,ACOX3,CPT1A,CPT2,CYP8B,DBI,FABP4,GK,LPL,and PPARG.Several DEGs,including those of the BMP family and receptors(BMP2,BMP5,BMP7,BMPR1B),LEPR,and SHH participate in the Hedgehog,TGF-beta,and cytokine-cytokine receptor interaction signaling pathways.The expression levels of bone morphogenetic proteins 2(BMP2),bone morphogenetic proteins 5(BMP5),and bone morphogenetic proteins 7(BMP7),and BMP receptor 1B(BMPR1B),sonic Hedgehog homolog(SHH),and leptin receptor(LEPR)were all significantly different between the two breeds(Additional file 3).Previous studies have shown that Hedgehog,TGF-beta,and cytokine-cytokine receptor interaction signaling pathways can regulate lipid metabolism[37-39]through the PPAR signaling pathway.This is consistent with the present results from KEGG pathway analysis.The cytokine-cytokine receptor interaction signaling pathway can regulate cell differentiation through the LEPR and TGF families(TGF-beta and BMP).Therefore,the cytokine-cytokine receptor interaction signaling pathway may share a similar role to the Hedgehog and TGF-beta signaling pathways as an upstream regulator of the PPAR signaling pathway in lipid metabolism.

Several DEGs,including the BMP family and its receptors,participated in more than one of the Hedgehog,TGF-beta,and cytokine-cytokine receptor interaction signaling pathways in the present study,so it is suggested that all of the Hedgehog,TGF-beta,and cytokine-cytokine receptor interaction signaling pathways play roles in the upstream regulation of the PPAR signaling pathway in lipid metabolism.These results suggest that these pathways form a network,along with others related to lipid metabolism,to influence IMF deposition in the chicken pectoralis major at hatching(Fig.5).The KEGG pathway analysis suggests that lipid metabolism in chicken pectoralis major at hatching is regulated both directly by genes encoding participating enzymes and indirectly via signaling pathways.

2.2.2 不同柱温对fs/i的影响 考察了不同柱温（25、28、30、32、35 ℃）对各fs/i的影响，结果（表3）朝藿定B、朝藿定A、朝藿定C、淫羊藿苷、木犀草素、槲皮素、川陈皮素、山柰酚、宝藿苷Ifs/i的RSD依次为0.57%、1.18%、0.98%、1.08%、2.08%、1.90%、0.76%、2.45%和2.81%，表明柱温的波动对各成分fs/i无显著影响。

Conclusion

In summary,residual sources of energy from the yolk sac are transported to be deposited as IMF in chickens at hatching.Genes and pathways related to lipid metabolism(such as PPAR,Hedgehog,TGF-beta,and cytokine-cytokine receptor interaction signaling pathways)account for greater IMF deposition in the pectoralis major of fast-growing chickens(AA)than that in a slow-growing breed(BJY).These findings provide new insights into the molecular mechanisms underlying lipid metabolism in chickens at hatching.

Additional files

Additional file 1:Annotation and changing of 787 DEGs in pectoralis major of AA and BJY chickens at hatching.(XLS 207 kb)

Additional file 2:The enriched GO terms among the 787 DEGs in both AA and BYJ chickens.(XLS 64 kb)

仅以民宿的布草清洗来说，布草会与用户亲密接触，一旦有任何的不干净，对用户体验是致命打击，曾有媒体报道：用户入住民宿后，房东无法更换清洁的布草，进而对平台产生质疑，一些民宿房东为了避免“麻烦”选用深色和带花纹的床单蒙混过关，常常一星期也不洗一次，行业的清洁监管令人担忧。

The significance of differences between groups was evaluated using Student’s t-test.P ＜ 0.05(*)or ＜0.01(**)wasconsidered　significant.Data　are　presented　as mean±SEM.

建筑企业应当重视对新技术的学习和运用，通过提升原有的操作技能，达到减小施工现场对大气的污染程度。例如改善钢筋的连接方式，对墙体的钻孔实施有效的防治措施，采用密封运输建筑垃圾等等，都是可以通过改善施工工艺技能而降低扬尘污染的方式。

Additional file 4:The enriched KEGG pathways based on 787 known DEGs in AA and BJY chickens.(XLS 57 kb)

方案二：在预制舱外电缆沟入口距离端部约1米处设置方形的迂回井，并在迂回井中间设置盘缆支架，用于收纳预制光缆余长。站内电缆沟贯穿预制舱底部，且舱两端的底部各设1个500×500 mm的进线孔，便于舱内外光缆接线。施工图设计时通过光、电缆敷设分层布置图明确线缆敷设顺序及位置，减少光缆冗余长度，实现整体光、电缆布置。采用预制舱外电缆沟设置方形的迂回井方案时，可有效控制光缆的余长，且便于日后预制光缆调整、检修、维护。本方案适用于各种配线方式时的预制光缆余长收纳，并可与方案一结合使用。具体方案如图4～图5所示。

Additional file 5:The enriched KEGG pathways based on 44 known

The energy remaining in birds at hatching is recovered from the yolk and stored(deposited)as IMF after transport,uptake,and re-esterification;a series of genes regulate these processes.To reveal the molecular regulation of IMF deposition in chicken pectoralis major at hatching,DEGs related to lipid metabolism were identified in the fast-and slow-growing chicken breeds.

DEGs related to lipid metabolism in AA and BJY chickens.(XLS 52 kb)

2.3 两组治疗前后血清CA125和D-二聚体变化比较 动态检测患者胸水中的CA125和血中的D-二聚体变化情况，结果显示在治疗之前，实验组和对照组胸水中的CA125和血中的D-二聚体的差异均无统计学意义（P＞0.05），但在治疗后实验组胸水中CA125和血中D-二聚体均明显低于对照组，差异均有统计学意义（P＜0.05），见表4。

Abbreviations

AA:Arbor acres chicken;ACACA:Acetyl-coenzyme A carboxylase alpha;ACAT1:Acetyl-coenzyme A acetyltransferase 1;ACOX2:Acyl-coenzyme A oxidase 2;ACOX3:Acyl-coenzyme A oxidase 3;ACSS1:Acyl-CoA synthetase short-chain family member 1;APOO:Apolipoprotein O;B4GALT3:UDPGal:betaGlcNAc beta 1,4-galactosyl transferase,polypeptide 3;BJY:Beijing you chicken;CPT1A:Carnitine palmitoyltransferase IA;CPT2:Carnitine palmitoyltransferase II;DAK:Dihydroxyacetone kinase 2 homolog;DEGs:Differentially expressed genes;DGAT2:Diacylglycerol O-acyltransferase homolog 2;FABP4:Fatty acid binding protein 4;FDR:False discovery rate;FUT9:Fucosyltransferase 9;GCNT1:N-glucosaminyl(N-acetyl)transferase 1;GK:Glycerol kinase;GO:Gene ontology;KEGG:Kyoto encyclopedia of genes and genomes;LPL:Lipoprotein lipase;LW:Live weight;PPARG:Peroxisome proliferator-activated receptor gamma;qPCR:Quantitative real time PCR;RBP7:Retinol binding protein 7;THRSP:Thyroid hormone responsive;TYE:Total yolk energy;u-TYE:LW-specific TYE amount

RNA samples were pooled from individuals(n=6)of each breed,as such a pooling strategy can dramatically improve accuracy when only one array is available for each biological condition[18].Seventeen genes that are well known to be related to lipid metabolism were selected,and nearly 100 qPCR tests were performed to confirm the microarray results.Overall,2.16%of the total DEGs(38.64%of the DEGs related to lipid metabolism)were verified as being present.As shown in Fig.2b,the fold changes in gene expression strongly corresponded(r=0.9797,P＜0.01)between the qPCR and microarray analyses.Despite the microarray analysis being performed once for each breed,the data exhibited high reliability and persuasive results were ensured because of the RNA pooling strategy and the high degree of verification.

The authors would like to thank W.Bruce Currie(Emeritus Professor,Cornell University)for his contributions to the preparation of the manuscript.

Funding

The research was supported by grants from the National Natural Science Foundation of China(31372305),the Agricultural Science and Technology Innovation Program(ASTIP-IAS04),and the Earmarked Fund for Modern Agro-industry Technology Research System(CARS-42).

Availability of data and materials

由同一名口腔医生采用精度为0.01 mm的电子数显游标卡尺(深圳佳林)测量第一前磨牙的全牙长、冠长、根长、冠近远中径、冠唇(颊)舌径、颈近远中径和颈唇(颊)舌径，每个数据测量3次，取平均值。肉眼观察并记录各牙根数目，其中双根型包括根分叉位于根上、根中、根尖1/3处，且有独立根尖孔。

All data generated or analyzed during this study available from the corresponding authors on reasonable request.

Authors’contributions

JW designed the study and was in charge of the overall project.LL,HC,and RF contributed to the design and performance of the study,the interpretation of data,and writing of the manuscript.MZ contributed to the design of the study and assisted in animal handling.GZ contributed to the design of the study,interpretation of data,and writing of the manuscript.RL contributed to reviewing the manuscript.All authors submitted comments on drafts,and read and approved the final manuscript.

Ethics approval

This study was conducted in accordance with the Guidelines for Experimental Animals established by the Ministry of Science and Technology(Beijing,China).All experimental protocols were approved by the Science Research Department(in charge of animal welfare)of the Institute of Animal Sciences,Chinese Academy of Agricultural Sciences(CAAS),Beijing,China.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

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