动物模型BLUP法评定内蒙古白绒山羊的遗传趋势

本研究应用动物模型BLUP法估计了1989～1998年内蒙古鄂托克旗阿尔巴斯白绒山羊种羊场抓绒量和抓绒后体重的遗传进展。结果为抓绒量的遗传进展呈上升趋势,抓绒后体重的遗传进展基本平稳。研究表明,内蒙古白绒山羊根据个体表型值选种,存在准确性较差和难以同时兼顾两个性状的缺点。本文认为今后内蒙古白绒山羊选种方法应该采用动物模型BLUP法。Abstract:In this study,animal model BLUP method was used to estimate genetic trend for cashmere yield and bodyweight during 1989～1998 at Albas goats farm,Etuoke Banner,Inner Mongolia.The results were that genetic trend for cashmere yield had a rising trend and for bodyweight showed smooth.The study indicated selecting Inner Mongolia cashmere goats based on phenotypic value had a low accuracy and was difficult to give consideration to the two traits at the same time.The article raised animal model BLUP method should be used to select Inner Mongolia white cashmere goats in future.     

动物模型BLUP法估计内蒙古白绒山羊育种值的研究

应用动物模型ＢＬＵＰ法估计了阿尔巴斯白绒山羊种羊场１９８９－１９９８年共１０个年度３９８１只个体的抓绒量和体重的单性状育种值,以及这两个性状的综合育种值。在模型中考虑的固定效应有年龄效应和性别－群体－年度效应、随机效应有个体的加性效应和个体永久性环境效应。比较育种值选择与表型值选择的结果表明：⑴公羔依据断乳重选择与依据育咱值选择的结果差异较大;⑵育成母羊依据表型值选择与依据综合育种值选择的结果差异     

糖尿病研究中实验动物模型的选择

自从1921年加拿大的班丁医生成功地从狗的胰腺中分离到胰岛素以后,应用动物开展实验糖尿病学的研究引起了人们广泛注意。由于实验动物及其疾病模型是临床假说与实验假说的试验基础,所以只有了解和选用适当的实验动物才可能获得准确、可靠、重复性好的实验结果。1实验动物在糖尿病研究中的选择目前糖尿病研究中主要使用哺乳类动物。根据不同的研究目的和条件,选择自发性或诱发性的动物模型。选择标准应符合以下基本原则:a.动物遗传背景清楚,微生物及环境控制良好,即标准化的等级动物。b.动物生理学体系和所形成的病理症状与人类相似。c.动物…     

改良的多平台水环境法在睡眠剥夺动物模型中的应用与评价

改良的多平台水环境法(modified multi-platform method, MMPM)由单平台及多平台水环境法发展而来,目前多用于制备睡眠剥夺(sleep deprivation, SD)动物模型。与单平台和早期的多平台水环境相比,MMPM可扩大动物的活动范围,减少群体分离和社会孤立带来的应激,具有易行性和适用性高及造模死亡率低的优点,是国内外较常用的一种SD造模方法。不过,影响SD模型制备的实验因素较多,MMPM在不同研究中的造模效果参差不齐。为提高模型的稳定性和实验的可重复性,本文梳理了MMPM在SD动物模型中的具体应用和评价方法,以供后期相关研究参考。     

2.5次微分伏安法对生物品中丙二醛的测定

以０．１ｍｏｌ／ＬＮＨ４Ｃｌ溶液为介质,用２．５次微分伏安法测定了丙二醛,线性范围为１．０＊１０＾－６至１．０＊１０＾－３ｍｏｌ／Ｌ,检测限达１．０＊１０＾－７ｍｏｌ／Ｌ。并测定了细胞培养液介质中新生ＳＤ大鼠室肌细胞样品的丙二醛。     

2.5次微分伏安法对生物样品中丙二醛的测定

以0.1mol/L NH₄Cl溶液为介质, 用2.5次微分伏安法测定了丙二醛, 线性范围为1.0×10^-6至1.0×10^-3 mol/L, 检测限达1.0×10^-7 mol/L. 并测定了细胞培养液介质中新生SD大鼠心室肌细胞样品中的丙二醛.     

西藏牦牛血液酶活性与生产性能的相关性研究

测定了28头西藏牦牛血液中6种酶的活性,探讨了6种酶活性与生产性能的关系。相关分析表明,LDH活性与产奶量、CAT活性与腹毛长呈极显著的正相关（P＜0．01）,AKP活性与体重、Amy活性与体重呈显著正相关（P＜0．05）,SOD活性与体重呈显著负相关（P＜0．05）。逐步回归分析表明,可以用LDH活性预测牦牛产奶量,用AKP、CAT、Amy 3种酶活性预测牦牛体重,用CAT、Amy活性预测牦牛腹毛长。因此,有望将LDH、AKP、CAT和Amy等酶活性作为生化遗传标记应用于牦牛产奶量、体重、腹毛长的选择中。     

微生物发酵法生产L-色氨酸的代谢工程研究

L-色氨酸作为人体内的一种必需氨基酸,广泛应用于医药、食品与饲料等行业.工业上采用的色氨酸生产方法有化学合成法、转化法及微生物发酵法.近年来,随着代谢工程在色氨酸菌种选育中的成功运用,微生物发酵法逐渐成为主要的色氨酸生产方法.系统综述了微生物发酵法生产色氨酸所涉及的代谢工程策略,包括生物合成色氨酸的代谢调控机制以及途径...     

西藏牦牛血液酶活性与生产性能的相关性研究

测定了 2 8头西藏牦牛血液中 6种酶的活性 ,探讨了 6种酶活性与生产性能的关系。相关分析表明 ,LDH活性与产奶量、CAT活性与腹毛长呈极显著的正相关 (P <0 .0 1 ) ,AKP活性与体重、Amy活性与体重呈显著正相关 (P <0 .0 5 ) ,SOD活性与体重呈显著负相关 (P <0 .0 5 )。逐步回归分析表明 ,可以用LDH活性预测牦牛产奶量 ,用AKP、CAT、Amy 3种酶活性预测牦牛体重 ,用CAT、Amy活性预测牦牛腹毛长。因此 ,有望将LDH、AKP、CAT和Amy等酶活性作为生化遗传标记应用于牦牛产奶量、体重、腹毛长的选择中     

婴幼儿配方粉及成人营养品中脂肪酸含量检测方法的性能研究

目的：建立适用于婴幼儿配方粉及成人营养品中脂肪酸检测的方法,并在不同基质中验证其性能。方法：在AOAC 2012.13方法基础上进一步修改建立了直接甲酯化法,并对其检测婴幼儿配方食品及成人营养品中主要功能性脂肪酸的能力进行验证。方法验证包括其准确性、回收率、精确度及定量限。本实验还研究了此方法在7种不同基质（乳基、豆基、部分水解蛋白及氨基酸配方）婴幼儿配方粉中的适用性,并与现行国标GB 5413.27-2010检测4种脂肪酸的能力进行了比对。同时,还评价了此方法检测包埋DHA原料的能力。结果：直接甲酯化法表现出了良好的准确性、回收率及精确度,在不同基质及使用不同包埋工艺的DHA原料中均显示了很好的适用性。此方法与现行国标方法测定7种乳粉试样中的4种脂肪酸的结果一致性均在90%~106%范围内,表现出了很高的一致性。结论：直接甲酯化法预处理步骤简单、方便、快捷,作为乳粉样品中脂肪酸含量的日常检测方法具有较大的推广潜力及价值。     

动物模型及多性状BLUP在家禽遗传鉴定中的应用

利用最佳线性无偏预测法(BLUP)估计家畜的育种值,目前除家禽外已在其它各家畜中得到了广泛的应用。本文利用动物模型和多性状BLUP对“京白Ⅰ系”蛋鸡在1986—1987年24个家系的777个个体的系统分组资料进行了分析,估计出了所有个体的复合育种值。其中考虑了两个性状(40周产蛋数和36周蛋重)和两个固定效应(鸡舍-鸡笼效应和孵化批次效应)。同时还对混合模型方程组维数较大时如何在微机上实现进行了研究,即(1)利用磁盘存取系数矩阵的非零元素和中间计算结果;(2)简化了多性状BLUP的计算,利用乔列斯基(Cholesky)分解变换后,此法建立的方程数是常规算法方程数的1/q(q为性状数);(3)简化了方程组迭代求解的方法,即利用块迭代法,这样大大缩短了计算的机吋,节省了费用,使BLUP在家禽中的推广应用成为可能。     

Long-term effects of selection based on the animal model BLUP in a finite population

Monte Carlo simulation was used to assess the long-term effects of truncation selection within small populations using indices (I=f+m) combining mid-parent [f=(a _i+a _d)/2] and Mendelian-sampling (m=a-f) evaluations provided by an animal model BLUP (a=f+m). Phenotypic values of panmictic populations were generated for 30 discrete generations. Assuming a purely additive polygenic model, heritability (h ₂) values were 0.10, 0.25 or 0.50. Two population sizes were considered: five males and 25 females selected out of 50 candidates of each sex (small populations, S) and 50 males and 250 females selected out of 500 candidates in each sex (large populations, L). Selection was carried out on the index defined above with = 1 (animal model BLUP), =1/2, or =0 (selection on within-family deviations). Mass selection was also considered. Selection based on the animal model BLUP (=1) maximized the cumulative genetic gain in L populations. In S populations, selection using = 1/2 and mass selection were more efficient than selection under an animal model (+ 3 to + 7% and + 1 to + 4% respectively, depending on h ²). Selection on within-family deviations always led to the lowest gains. In most cases, the variance of response to selection between replicates did not depend on the selection method. The within-replicate genetic variance and the average coefficient of inbreeding (F) were highly affected by selection with =1 or 1/2, especially in populations of size S. As expected, selection based on within-family deviations was less detrimental in that respect. The number of copies of founder neutral genes at a separate locus, and the probability vector of origin of the genes in reference to the founder animals, were also observed in addition to F values. The conclusion was that selection procedures placing less emphasis on family information might be interesting alternatives to selection based on animal model BLUP, especially for small populations with long-term selection objectives.     

The effect of using approximate gametic variance covariance matrices on marker assisted selection by BLUP

Under additive inheritance, the Henderson mixed model equations (HMME) provide an efficient approach to obtaining genetic evaluations by marker assisted best linear unbiased prediction (MABLUP) given pedigree relationships, trait and marker data. For large pedigrees with many missing markers, however, it is not feasible to calculate the exact gametic variance covariance matrix required to construct HMME. The objective of this study was to investigate the consequences of using approximate gametic variance covariance matrices on response to selection by MABLUP. Two methods were used to generate approximate variance covariance matrices. The first method (Method A) completely discards the marker information for individuals with an unknown linkage phase between two flanking markers. The second method (Method B) makes use of the marker information at only the most polymorphic marker locus for individuals with an unknown linkage phase. Data sets were simulated with and without missing marker data for flanking markers with 2, 4, 6, 8 or 12 alleles. Several missing marker data patterns were considered. The genetic variability explained by marked quantitative trait loci (MQTL) was modeled with one or two MQTL of equal effect. Response to selection by MABLUP using Method A or Method B were compared with that obtained by MABLUP using the exact genetic variance covariance matrix, which was estimated using 15 000 samples from the conditional distribution of genotypic values given the observed marker data. For the simulated conditions, the superiority of MABLUP over BLUP based only on pedigree relationships and trait data varied between 0.1% and 13.5% for Method A, between 1.7% and 23.8% for Method B, and between 7.6% and 28.9% for the exact method. The relative performance of the methods under investigation was not affected by the number of MQTL in the model.     

抽动-秽语综合征动物模型的建立和评价

目的研究建立儿童抽动秽语综合征的动物模型,为基础和临床研究提供支撑。方法实验动物选择刚成年SD大鼠,亚氨基二丙腈腹腔连续注射7 d,采用行为学观察大鼠自主运动和刻板运动评分,液相色谱法测定脑组织DA、NE含量,组织学检查脑组织神经元病理学变化等对模型综合评价。结果模型大鼠的运动行为和刻板运动呈现典型的抽动秽语综合征行为特征,脑组织DA、NE含量以及神经元数目和形态等神经生物学病变明显。结论亚氨基二丙腈腹腔注射可诱发大鼠儿童抽动秽语综合征模型。     

Genomic BLUP Decoded: A Look into the Black Box of Genomic Prediction

Genomic best linear unbiased prediction (BLUP) is a statistical method that uses relationships between individuals calculated from single-nucleotide polymorphisms (SNPs) to capture relationships at quantitative trait loci (QTL). We show that genomic BLUP exploits not only linkage disequilibrium (LD) and additive-genetic relationships, but also cosegregation to capture relationships at QTL. Simulations were used to study the contributions of those types of information to accuracy of genomic estimated breeding values (GEBVs), their persistence over generations without retraining, and their effect on the correlation of GEBVs within families. We show that accuracy of GEBVs based on additive-genetic relationships can decline with increasing training data size and speculate that modeling polygenic effects via pedigree relationships jointly with genomic breeding values using Bayesian methods may prevent that decline. Cosegregation information from half sibs contributes little to accuracy of GEBVs in current dairy cattle breeding schemes but from full sibs it contributes considerably to accuracy within family in corn breeding. Cosegregation information also declines with increasing training data size, and its persistence over generations is lower than that of LD, suggesting the need to model LD and cosegregation explicitly. The correlation between GEBVs within families depends largely on additive-genetic relationship information, which is determined by the effective number of SNPs and training data size. As genomic BLUP cannot capture short-range LD information well, we recommend Bayesian methods with t-distributed priors.     

哮喘动物模型评价与观察指标的研究进展

全面、成功地评价一个与临床发病机制相似的、稳定可靠的支气管哮喘动物模型非常重要,本文参考近年来哮喘动物模型的一般评价指标和机理研究评价指标,对观察与评价指标的研究进展进行了整理分析,以供参考。     

Prediction of oil palm (Elaeis guineensis, Jacq.) agronomic performances using the best linear unbiased predictor (BLUP)

Reciprocal recurrent selection (RRS) has been adopted for oil palm breeding in Indonesia.Due to a long selection cycle and the large area required, a satisfactory oil palm progeny trial is difficult to conduct.Knowledge of the parental genetic parametersis very important in achieving the expected genetic progress, but the evaluation of these parameters is constrained by highly unbalanced data sets. In this study, the unbalanced agronomic data sets and the pedigree information of an oil palm breeding programme in Indonesia were analysed by using the restricted maximum likelihood (REML) and the best linear unbiased predictor (BLUP)methods. The characters analysed were bunch and oil yields of the adult period (from 7 to 9 years after planting). The coefficients of parentage varied from 0.125 to 0.891 and from zero to 0.750 between parents in the Deli and African groups, respectively.The average coefficients of inbreeding were 0.269 and 0.166 for the parents within the Deli and African groups, respectively. The additive variances of the bunch number, industrial oil-extraction rate and oil yield characters were higher in the parents of the Deli group than those in the African ones. The coefficients of correlation between the predicted and observed hybrids performances varied from 0.55 to 0.64 for oil yield, 0.49 to 0.71 for bunch number, 0.47 to 0.58 for bunch production, 0.48 to 0.64 for industrial oil-extraction rate and 0.42 to 0.56 for plant-height increment. For selection on the basis of oil yield character, BLUPs ability to predict single-cross performance should be sufficient, and will result in a significant contribution to the oil palm seed and clone productions. Received: 3 January 2000 / Accepted: 3 July 2000     

Reduced Expression of GABA Transporter GAT3 in Helpless Rats,an Animal Model of Depression

Mood disorders have been linked to glial and synaptic pathology such as disturbed neurotransmission of γ-aminobutyric acid (GABA). We evaluated the expression of GABAergic marker genes in rats with helpless behaviour, an animal model of depression. Male Sprague-Dawley rats from inbred lines were tested for helpless behaviour and grouped according to failures in terminating foot shock currents. Expression levels of GABAergic marker genes were assessed using semiquantitative in situ-hybridization. Animals with congenital helpless behaviour (cH) were unable to escape current exposure in contrast to cH-animals derived from the same litters with low failure rates and to non-helpless animals (cNH). We found a significant downregulation of the GABA transporter GAT3 in cLH rats. GAT1 showed small changes, glutamic acid decarboxylase (GAD67) and the vesicular GABA transporter were not significantly altered. Reduced GABA transporter expression is well in concert with the behavioural phenotypes of knockout animals and strengthens the hypothesis of impaired glial functions in depression.     

肝纤维化动物模型造模方法的研究进展

肝纤维化是肝脏受到损伤后细胞外基质合成、降解与沉积不平衡的一种修复反应。对肝纤维化进行早期诊断、早期治疗,预防肝硬化的发生、发展,对肝病患者的生命质量具有重要的意义。而肝纤维化动物模型的建立,既可深入全面地研究肝纤维化发病机制,又可为临床筛选防治肝纤维化药物提供基础研究。通过对常用的肝纤维化动物模型造模方法的阐述,为肝纤维化的基础实验研究和临床治疗提供参考。