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中国荷斯坦牛健康性状遗传参数估计

中国畜牧兽医 2024年第6期51卷 2501-2507页

作者：赵孝凤郭刚曹杰王雅春张毅中国农业大学动物科学技术学院北京100193 北京首农畜牧发展有限公司北京100176 中国农业大学动物医学院北京100193

【目的】基于中国荷斯坦牛牧场实际数据,通过遗传分析得到5种常见疾病的遗传参数,为制定包含健康性状的奶牛育种方案提供科学依据,促进中国牛群健康水平遗传改良。【方法】基于全国30个奶牛场2019―2022年95 710头牛的230 826条产犊记录... 详细信息

【目的】基于中国荷斯坦牛牧场实际数据,通过遗传分析得到5种常见疾病的遗传参数,为制定包含健康性状的奶牛育种方案提供科学依据,促进中国牛群健康水平遗传改良。【方法】基于全国30个奶牛场2019―2022年95 710头牛的230 826条产犊记录和121 811头牛的333 038条疾病记录,经过质控后整合形成表型数据集,根据每个个体每胎次内是否发生疾病定义其表型为0(健康)或1(发病);针对乳房炎(mastitis, MAST)、临床性酮病(ketosis, KET)、胎衣不下(retained placenta, RETP)、子宫炎(metritis, MET)和真胃变位(displaced abomasum, DA)性状,采用单性状重复力模型估计各性状方差组分,计算遗传力和重复力,用双性状重复力模型估计性状间的表型相关和遗传相关,模型中包含场年、胎次、产犊季节固定效应。通过卡方检验对比公牛估计育种值(estimated breeding value, EBV)排名前20位和后20位公牛后代的发病率,探究了对健康性状进行选择的效果。【结果】MAST、KET、RETP、MET、DA性状的遗传力分别为0.063±0.005、0.051±0.005、0.015±0.002、0.033±0.003和0.020±0.002,均为低遗传力性状;性状间的遗传相关在―0.110~0.684之间,其中KET和DA、MET和RETP之间表现出较强正相关,遗传相关达到0.648和0.402。针对所有性状,EBV排名前20位公牛的后代平均发病率均极显著低于排名后20位的公牛后代(P<0.01),其发病率差异为2.2~7.4倍。【结论】本研究中5种健康性状均为低遗传力性状,但健康性状具有选育价值,在奶牛育种中应兼顾对健康性状的遗传改良,实现平衡育种目标。

关键词：奶牛遗传参数健康性状平衡育种

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荷斯坦牛关键奶流速指标筛选及影响因素分析

中国畜牧兽医 2024年第1期51卷 212-219页

作者：陈少侃罗汉鹏马烨桦刘刚王迪郝科比王雅春郭刚北京首农畜牧发展有限公司北京100176 中国农业大学动物科技学院农业农村部动物遗传育种与繁殖(家畜)重点实验室畜禽育种国家工程实验室北京100193

【目的】本研究旨在探究挤奶流速指标的群体表型变化规律、指标间相关性及主要影响因素,筛选荷斯坦牛关键奶流速指标。【方法】本研究收集了北京地区某规模化牧场2162头泌乳牛1181628条奶流速数据,包含班次奶量及11项奶流速指标(平均流... 详细信息

【目的】本研究旨在探究挤奶流速指标的群体表型变化规律、指标间相关性及主要影响因素,筛选荷斯坦牛关键奶流速指标。【方法】本研究收集了北京地区某规模化牧场2162头泌乳牛1181628条奶流速数据,包含班次奶量及11项奶流速指标(平均流速、挤奶时长、高峰流速、慢速出奶时间占比、脱杯流速、0―15 s流速、15―30 s流速、30―60 s流速、60―120 s流速、前2 min产量和前2 min产量占比),并对班次奶量与上述奶流速指标进行了正态性检验、回归分析、相关性分析,以及影响因素分析。【结果】班次奶量与11项奶流速指标均呈正态分布;其中0―15 s流速、15―30 s流速、30―60 s流速、60―120 s流速、前2 min产量、高峰流速、平均流速和挤奶时长与班次奶量呈正向回归关系,且在各因素水平下变化规律一致;各指标间均存在显著的相关关系(P<0.05),相关系数在—0.80~0.95之间;相关性分析结果表明,平均流速和前2 min产量可作为关键奶流速指标,随着班次奶量的增加均呈现逐渐增加的规律,且在不同年份、季节、胎次、泌乳阶段和挤奶班次均差异显著(P<0.05)。【结论】平均流速和前2 min产量可作为奶流速指标考核的关键指标,但在实际生产管理中,需根据牛群结构和环境变化来设定指标的参考值。随着精细化管理,对于平均流速和前2 min产量可以逐步设定更高参考阈值来获取更高的产奶量,进而增加经济效益。

关键词：奶流速班次奶量荷斯坦牛

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奶牛乳脂抑制研究进展

中国畜牧杂志 2024年第7期60卷 27-34页

作者：刘广镭刘帅王雅晶王雅春候国彬曹志军张海亮中国农业大学动物科学技术学院动物营养学国家重点实验室北京100193 中国农业大学动物科学技术学院农业农村部动物遗传育种与繁殖(家畜)重点实验室畜禽育种国家工程实验室北京100193 北京农学院动物科学技术学院北京102206

牛奶具有极高的营养价值,含有丰富的棕榈酸、亚油酸等不饱和脂肪酸,牛奶的乳脂组成在一定程度上会影响牛乳的品质和口感,甚至影响原料奶价格。乳脂抑制也称低乳脂综合征,是牛奶生产中的难题之一。本文综述了乳脂抑制研究现状、乳脂合成... 详细信息

牛奶具有极高的营养价值,含有丰富的棕榈酸、亚油酸等不饱和脂肪酸,牛奶的乳脂组成在一定程度上会影响牛乳的品质和口感,甚至影响原料奶价格。乳脂抑制也称低乳脂综合征,是牛奶生产中的难题之一。本文综述了乳脂抑制研究现状、乳脂合成过程及其影响因素,并概述缓解乳脂抑制的可行措施,以期为改善牛奶品质及提高奶牛生产水平提供参考和依据。

关键词：奶牛乳脂合成乳脂抑制脂肪酸机制

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DNA微阵列芯片法在非结核分枝杆菌菌种鉴定的应用探讨

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哈尔滨医药 2024年第1期44卷 26-28页

作者：谭蛟王亚春王亚丽夏爽程美锦王伟河南省胸科医院医学检验科郑州大学附属胸科医院河南省传染病(结核病)临床医学研究中心河南郑州450003

目的为临床工作中非结核分枝杆菌(NTM)的感染和防治提供科学依据。方法收集疑似结核分枝杆菌感染患者标本(包括呼吸道标本痰液、灌洗液以及非呼吸道标本无菌体液)共1089例,采用DNA微阵列芯片法进行检测,分析分枝杆菌菌种的分布特点。结... 详细信息

目的为临床工作中非结核分枝杆菌(NTM)的感染和防治提供科学依据。方法收集疑似结核分枝杆菌感染患者标本(包括呼吸道标本痰液、灌洗液以及非呼吸道标本无菌体液)共1089例,采用DNA微阵列芯片法进行检测,分析分枝杆菌菌种的分布特点。结果1089份标本中检出结核分枝杆菌878份(80.62%),NTM211份(19.38%)。其中非结核分枝杆菌菌种分布有5种,胞内分枝杆菌153例(72.51%),鸟分枝杆菌28例(13.27%),龟脓分枝杆菌复合群19例(9%),堪萨斯分枝杆菌10例(4.74%),耻垢分枝杆菌1例(0.48%)。非结核分枝杆菌感染人员分布男性127例(60.19%),女性84例(39.81%),年龄分布以老年为主,60岁以上103例(48.82%),男性71例(68.93%),女性32例(31.07%)。结论疑似结核分枝杆菌患者检出NTM共有5种,排名前三的NTM种类是胞内分枝杆菌、鸟分枝杆菌和龟脓分枝杆菌复合群,感染人群以老年男性为主。

关键词：非结核分枝杆菌菌种鉴定 DNA微阵列芯片技术

Approximations to Isentropic Planar Magneto-Hydrodynamics Equations by Relaxed Euler-Type Systems

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Chinese Annals of Mathematics,Series B 2024年第3期45卷 413-440页

作者： yachun LI Zhaoyang SHANG Chenmu wang Liang ZHAO School of Mathematical Sciences CMA-ShanghaiMOE-LSC and SHL-MACShanghai Jiao Tong UniversityShanghai 200240China School of Finance Shanghai Lixin University of Accounting and FinanceShanghai 201209China School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences Harbin Engineering UniversityHarbin 150001China Mathematical Modelling&Data Analytics Center Oxford Suzhou Centre for Advanced ResearchSuzhou 215123JiangsuChina

In this paper, the authors consider an approximation to the isentropic planar Magneto-hydrodynamics(MHD for short) equations by a kind of relaxed Euler-type system. The approximation is based on the generalization of the Maxwell law for nonNewtonian fluids together with the Maxwell correction for the Ampe`re law, hence the approximate system becomes a first-order quasilinear symmetrizable hyperbolic systems with partial dissipation. They establish the global-in-time smooth solutions to the approximate Euler-type equations in a small neighbourhood of constant equilibrium states and obtain the global-in-time convergence towards the isentropic planar MHD equations. In addition, they also establish the global-in-time error estimates of the limit based on stream function techniques and energy estimates for error variables.

关键词： Planar MHD equations Relaxation limits Global convergence Stream function

Cs_(3)Bi_(2)l_(9)-hydroxyapatite composite waste forms for cesium and iodine immobilization

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Journal of Advanced Ceramics 2022年第5期11卷 712-728页

作者： Kun YANG yachun wang Junhua SHEN Spencer M.SCOTT Brian J.RILEY John D.VIENNA Jie LIAN Department of Mechanical Aerospaceand Nuclear EngineeringRensselaer Polytechnic InstituteTroyUSA Department of Materials Science&Engineering Rensselaer Polytechnic InstituteTroyUSA Savannah River National Laboratory AikenUSA Pacific Northwest National Laboratory RichlandUSA

Perovskite-based ceramic composites were developed as potential waste form materials for immobilizing cesium(Cs)and iodine(I)with high waste loadings and chemical *** perovskite Cs_(3)Bi_(2)I_(9)has high Cs(22 wt%)and I(58 wt%)content,and thus can be used as a potential host phase to immobilize these critical *** this work,the perovskite Cs_(3)Bi_(2)I_(9)phase was synthesized by a cost effective solution-based approach,and was embedded into a highly durable hydroxyapatite matrix by spark plasma sintering to form dense ceramic composite waste *** chemical durabilities of the monolithic Cs_(3)Bi_(2)I_(9)and Cs_(3)Bi_(2)I_(9)-hydroxyapatite composite pellets were investigated by static and semi-dynamic leaching tests,*** and I are incongruently released from the matrix for both pure Cs_(3)Bi_(2)I_(9)and composite *** normalized Cs release rate is faster than that of I,which can be explained by the difference in the strengths between Cs-I and Bi-I bonds as well as the formation of insoluble micrometer-sized BiOI *** activation energies of elemental releases based on dissolution and diffusion-controlled mechanisms are determined with significantly higher energy barriers for dissolution from the composite versus that of the monolithic Cs_(3)Bi_(2)I_(9).The ceramic-based composite waste forms exhibit excellent chemical durabilities and waste loadings,commensurate with the state-of-the-art glass-bonded perovskite composites for I and Cs immobilization.

关键词： cesium(Cs) iodine(Ⅰ) perovskite nuclear waste hydroxyapatite

Genomic and transcriptomic analyses enable the identification of important genes associated with subcutaneous fat deposition in Holstein cows

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Journal of Genetics and Genomics 2023年第6期50卷 385-397页

作者： Hailiang Zhang Siyuan Mia Luiz F.Brito Lirong Hu Lei wang Longgang Ma Qing Xu Gang Guo Ying Yu yachun wang Laboratory of Animal Genetics Breeding and ReproductionMinistry of Agriculture of ChinaNational Engineering Laboratory of Animal BreedingCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Department of Animal Sciences Purdue UniversityWest LafayetteIN 47907USA Institute of Life Sciences and Bioengineering Beijing Jiaotong UniversityBejing 100044China Beijing Sunlon Livestock Development Co.Ltd Beijing 100176China

Subcutaneous fat deposition has many important roles in dairy cattle,including immunological defense and mechanical *** main objectives of this study are to identify key candidate genes regulating subcutaneous fat deposition in high-producing dairy cows by integrating genomic and transcriptomic datasets.A total of 1654 genotyped Holstein cows are used to perform a genome-wide association study(GWAS)aiming to identify genes associated with subcutaneous fat ***,weighted gene co-expression network analyses(WGCNA)are conducted based on RNA-sequencing data of 34 cows and cow yield deviations of subcutaneous fat ***,differentially expressed(DE)m RNA,lnc RNA,and differentially alternative splicing genes are obtained for 12 Holstein cows with extreme and divergent phenotypes for subcutaneous fat ***-six protein-coding genes are identified as candidate genes regulating subcutaneous fat deposition in Holstein cattle based on *** overlapping genes are identified based on the analyses of DE genes and ***,the candidate genes identified based on GWAS,WGCNA,and analyses of DE genes are significantly enriched for pathways involved in metabolism,oxidative phosphorylation,thermogenesis,fatty acid degradation,and glycolysis/gluconeogenesis *** all findings,the NID2,STARD3,UFC1,DEDD,PPP1R1B,and USP21 genes are considered to be the most important candidate genes influencing subcutaneous fat deposition traits in Holstein *** study provides novel insights into the regulation mechanism underlying fat deposition in high-producing dairy cows,which will be useful when designing management and breeding strategies.

关键词： Bovine Body condition score Subcutaneous adipose GWAS WGCNA RNA-Seq

Sugarcane transcription factor ScWRKY4 negatively regulates resistance to pathogen infection through the JA signaling pathway

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The Crop Journal 2024年第1期12卷 164-176页

作者： Dongjiao wang Wei wang Shoujian Zang Liqian Qin Yanlan Liang Peixia Lin yachun Su Youxiong Que Key Laboratory of Sugarcane Biology and Genetic Breeding Ministry of Agriculture and Rural AffairsKey Laboratory of GeneticsBreeding and Multiple Utilization of CropsMinistry of EducationCollege of AgricultureFujian Agriculture and Forestry UniversityFuzhou 350002FujianChina National Key Laboratory for Tropical Crop Breeding Institute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesSanya 572024HainanChina

WRKY transcription factors,transcriptional regulators unique to plants,play an important role in defense response to pathogen ***,the resistance mechanisms of WRKY genes in sugarcane remain *** the present study,gene ontology(GO)enrichment analysis revealed that WRKY gene family in sugarcane was extensively involved in the response to biotic stress and in defense *** identified gene ScWRKY4,a classⅡc member of the WRKY gene family,in sugarcane cultivar *** gene was induced by salicylic acid(SA)and methyl jasmonate(MeJA)***,expression of ScWRKY4 was down-regulated in smut-resistant sugarcane cultivars but up-regulated in smutsusceptible sugarcane cultivars infected with Sporisorium ***,stable overexpression of the ScWRKY4 gene in Nicotiana benthamiana enhanced susceptibility to Fusarium solani *** and caused down-regulated expression of immune marker-related *** analysis indicated suppressed expression of most JAZ genes in the signal transduction ***4 interacted with ScJAZ13 to repress its *** thus hypothesized that the ScWRKY4 gene was involved in the regulatory network of plant disease resistance,most likely through the JA signaling *** present study depicting the molecular involvement of ScWRKY4 in sugarcane disease resistance lays a foundation for future investigation.

关键词： Disease resistance Expression profile Transcriptome analysis WRKY transcription factors

Predicting nitrogen use efficiency,nitrogen loss and dry matter intake of individual dairy cows in late lactation by including mid‑infrared spectra of milk samples

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Journal of Animal Science and Biotechnology 2023年第3期14卷 1287-1299页

作者： Rui Shi Wenqi Lou Bart Ducro Aart van der Linden Han A.Mulder Simon J.Oosting Shengli Li yachun wang Laboratory of Animal Genetics Breeding and ReproductionMinistry of Agriculture of ChinaNational Engineering Laboratory of Animal BreedingCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Wageningen University&Research Animal Breeding and Genomics P.O.Box 3386700 AH Wageningenthe Netherlands Animal Production System Group Wageningen University&ResearchP.O.Box 3386700 AH Wageningenthe Netherlands

Background Nitrate leaching to groundwater and surface water and ammonia volatilization from dairy farms have negative impacts on the ***,the increasing demand for dairy products will result in more pollution if N losses are not ***,a more efficient,and environmentally friendly production system is needed,in which nitrogen use efficiency(NUE)of dairy cows plays a key *** genetically improve NUE,extensively recorded and cost-effective proxies are essential,which can be obtained by including mid-infrared(MIR)spectra of milk in prediction models for *** study aimed to develop and validate the best prediction model of NUE,nitrogen loss(NL)and dry matter intake(DMI)for individual dairy cows in *** A total of 86 lactating Chinese Holstein cows were used in this *** data editing,704 records were obtained for calibration and *** prediction models with three different machine learning algorithms and three kinds of pre-processed MIR spectra were developed for each *** showed that the coefficient of determination(R2)of the best model in within-herd validation was 0.66 for NUE,0.58 for NL and 0.63 for *** external validation,reasonable prediction results were only observed for NUE,with R2 ranging from 0.58 to 0.63,while the R2 of the other two traits was below *** infrared waves from 973.54 to 988.46 cm−1 and daily milk yield were the most important variables for *** The results showed that individual NUE can be predicted with a moderate accuracy in both within-herd and external *** model of NUE could be used for the datasets that are similar to the calibration *** prediction models for NL and 3-day moving average of DMI(DMI_a)generated lower accuracies in within-herd *** also indicated that information of MIR spectra variables increased the predictive ability of ***,pre-processed MIR spectra do not result in higher acc

关键词： Dairy cow Environment Mid-infrared spectra Nitrogen use efficiency Prediction