4个肉牛品种微卫星多态性分析

本研究探讨了引进牛种（西门塔尔牛、利木赞牛）和山东地方黄牛（鲁西黄牛、利鲁牛）在20个微卫星位点上的多态性。试验从不同地区的种公牛站采集鲁西黄牛、利鲁牛、利木赞牛和西门塔尔牛的血液或精液样本,分别为56、27、31和30个,共计144个样本,血液样本采用Lab-Aid基因组DNA分离试剂盒提取基因组DNA,精液样本采用高盐法提取基因组DNA。利用20个微卫星标记,采用荧光标记毛细管电泳方法,对4个肉牛品种的DNA多态性进行分析,主要研究了每个群体的遗传变异指标（等位基因数、多态信息含量和杂合度）及群体间的遗传关系（F-统计量和基因流）。结果表明,肉牛基因组DNA条带整齐,无拖尾现象,质量较好,可用于本试验。20个微卫星座位中共检测到211个等位基因,平均等位基因数为10.6个。群体的平均观测杂合度在0.6147~0.7176之间,平均期望杂合度在0.6735~0.7862之间。在所有群体中各位点的多态信息含量在0.4853~0.8714之间,平均为0.7284,但在各个群体内的差异较大。近交系数及基因流分析结果表明,4个肉牛品种近交系数较低,群体间平均近交系数为0.085,每个微卫星位点的基因流均>1。总体来看,所选用的20个微卫星座位多态信息含量高,可作为有效遗传标记用于肉牛品种间遗传多样性分析。     

Analysis of factors affecting the electric conductivity of cow's milk--breed, locale, season

The problem was studied in a set of 678 mammary glands of 212 cows - crossbreds between the Holstein-Friesian breed with the Slovak Spotted cattle, crossbreds of the Black-Pied Lowland and Bohemian Spotted breed, and three-way crossbreds of the Black-Pied Lowland, Swedish White and Bohemian Spotted cattle. The confrontation of the confidence intervals of milk conductivity (MC) in healthy mammary glands at alpha = 0.05 showed that in the crossbreds of the Black-Pied Lowland cattle the MC was statistically significantly higher than in the breed types of the Holstein-Friesian cattle. The MC values decrease when there is a larger proportion of the blood of beef-and-dairy cattle (Slovak Spotted and Bohemian Spotted breeds). The locality where the stock was kept was found to act as an important factor underlying MC only in cases when both the geographical conditions and breed proportions were different. In a set homogenized with respect to the breeds, statistically significant differences in MC were demonstrated between the spring and summer season, spring and autumn, summer and autumn, and autumn and winter season.     

8个牛品种的大理石花纹评分相关基因变异的微卫星DNA池分析

本研究以8个牛品种为研究对象,利用与大理石花纹评分基因相关的7个微卫星位点结合DNA池分析技术,探讨微卫星DNA多态性与8个牛品种大理石花纹评分间的关系,并根据性状同质性原理预测品种组合,以加快生产出高端"雪花"牛肉。结果表明:日本和牛与荷斯坦牛、安格斯牛、渤海黑牛的相似性系数均超过0.8,而日本和牛与其他牛品种的的相似性系数均小于0.8。利用MEGA4软件采用邻接法进行聚类,利木赞牛与西门塔尔牛先聚合在一起,再与草原红牛聚合;渤海黑牛与鲁西黄牛2个地方良种聚合在一起,以上5个品种聚为第1大类。荷斯坦牛与日本和牛聚合,再与安格斯牛聚在一起,它们聚为第2大类。根据本研究结果和国外肉牛杂交生产实践,从牛肉大理石花纹性状的同质性出发,建议利用日本和牛、荷斯坦牛为亲本,杂交生产高档"雪花"牛肉,以解决我国的肉牛牛源短缺问题。     

Genetic diversity and assignment tests among seven French cattle breeds based on microsatellite DNA analysis

Genetic variability and relationships among six native French cattle breeds (Abondance, Tarentaise, Villard de Lans, Montbéliarde, Limousin, and Charolais) and one foreign breed (Holstein) were investigated using 23 microsatellite markers. These breeds were also compared with four Swiss breeds genotyped in a previously published study. Interestingly, the French alpine breeds have smaller population sizes but showed higher genetic variability than the larger Holstein breed. Neighbor-joining trees and PCA (principal components analysis) showed that alpine breeds tend to cluster together. Abondance and Tarentaise breeds were closely related, whereas the Holstein was highly differentiated from all breeds analyzed. Two different assignment tests for determining the breed of origin of individuals were compared: "direct" and "exclusion-simulation" approaches. The exclusion-simulation significance test correctly assigns fewer individuals than the direct approach but provides a confidence level (e.g., P < 0.01) for each individual being assigned. Accurate assignment with high statistical confidence is required for animal traceability. Unfortunately, the accuracy of assignment greatly decreases as the threshold level of confidence of assignment increases (e.g., from P < 0.05 to P < 0.001). Assignment accuracy also greatly declines as the level of population differentiation decreases below the level often found between related breeds (e.g., F(ST) < 0.1).     

肉牛改良蒙古牛效果分析

上世纪70年代以来锡林郭勒盟先后引进安格斯、利木赞、夏洛来、西门塔尔等肉牛品种改良蒙古牛.分析测定了不同品种杂交一代公母牛及蒙古牛6月龄、18月龄和30月龄体重的变化规律.结果安蒙、利蒙、夏蒙、西蒙杂一代6月龄公母犊平均体重分别比同龄蒙古牛增加37.87 kg、40.60 kg、66.35 kg和43.71 kg,分别提高32.75%、35.11%、57.37%和38.0%.18月龄公母牛平均体重分别比同龄蒙古牛增加78.75 kg、96.73 kg、107.72 kg和100.59 kg,分别提高35.84%、44.02%、49.03%和45.78%.30月龄公母牛平均体重分别比同龄蒙古牛增加67.07 kg、84.86 kg、110.18 kg和116.26 kg,分别提高19.86%、25.13%、32.62%和34.42%.     

应用灰色系统理论综合评估外来牛改良本地牛生长性能的研究

[目的]科学便捷地评价外来牛改良本地牛生长性能效果,为科学的引种改良提供依据.[方法]本文应用灰色系统理[结论] 分别对相同生长条件下的12月龄德南F1、皮南F1、夏南F1、利南F1的体高、体长、胸围、管围、体重5项指标进行分析,建立综合评估模型,并对其生长性能进行了综合评估.[结果]夏南F1、德南F1得分最高,综合生长性能最好.[结论]德国黄牛和夏洛来牛改良南阳本地牛效果最好,适宜在本土推广.     

Inbreeding effects on postweaning production traits, conformation, and calving performance in Irish beef cattle

The objective of this study was to quantify the effect of inbreeding on carcass quality, growth rate, live conformation measures, and calving performance in purebred populations of Charolais, Limousin, Simmental, Hereford, and Angus beef cattle using data from Irish commercial and pedigree herds. Variables analyzed are reflective of commercial farming practices. Inbreeding was included in a linear mixed model as either a class variable or a linear continuous variable. Nonlinear effects were nonsignificant across all traits. Inbred animals had decreased carcass weight and less carcass fat. The effects of inbreeding were more pronounced in the British beef breeds. Effects for carcass weight ranged from -0.87 kg (Charolais) to -1.90 kg (Hereford) per 1% increase in inbreeding. Inbred Charolais and Hereford animals were younger at slaughter by 3 and 5 d, respectively, per percentage of increase in inbreeding, whereas the effect of inbreeding on age at slaughter differed significantly with animal sex in the Limousin and Angus breeds. Inbred Limousin and Angus heifers were younger at slaughter by 5 and 7 d, respectively, per percentage of increase in inbreeding. Continental animals were more affected by inbreeding for live muscling and skeletal conformational measurements than the British breeds; inbred animals were smaller and narrower with poorer developed muscle. Calf inbreeding significantly affected perinatal mortality in Charolais, Simmental, and Hereford animals. The effects were dependent upon dam parity and calf sex; however, where significant, the association was always unfavorable. Dam inbreeding significantly affected perinatal mortality in Limousin and Hereford animals. Effects differed by parity in Limousins. Inbred first-parity Angus dams had a greater incidence of dystocia. Although the effects of inbreeding were some-times significant, they were small and are unlikely to make a large financial effect on commercial beef production in Ireland.     

草原红牛微卫星DNA多态性的研究

为了更好地培育和改良肉用草原红牛，利用草原红牛、夏洛莱牛、西门塔尔牛、利木赞牛、蒙古牛基因组DNA，用8对微卫星引物进行PCR扩增，并将扩增产物置于1．5％琼脂糖电泳进行观察，如有所需的带则转入8％聚丙烯酰胺变性凝胶(PAGE)中电泳分离，绘制指纹图谱。结果表明微卫星标记方法是一种理想的研究方法。     

肉牛杂交亲本遗传距离与杂种优势的相关性研究

利用11个微卫星标记研究川南山地黄牛、海福特牛、黑安格斯牛、红安格斯牛、利木赞牛、西门塔尔牛、德国黄牛的遗传多样性,分析肉牛亲本间微卫星标记遗传距离与体尺、体重杂种优势间的相关性。结果表明:11个微卫星基因座平均有效等位基因数为4.5422,7个牛种的多态信息含量在0.3434~0.4207,平均杂合度为0.6868~0.8413,7个牛种均具有丰富的多态性。亲本间遗传距离与体尺、体重杂种优势间相关系数偏小(-0.003~0.304),均未达到显著水平,用微卫星标记遗传距离预测肉牛体尺、体重杂种优势还有待进一步探讨。     

不同肉牛品种杂交西门塔尔杂种牛效果的研究

为了研究不同肉牛品种杂交改良西门塔尔杂种牛的效果,筛选出产肉量高、肉质好、抗逆性强的品种杂交组合,为大规模开展杂交提供依据,试验采用红安格斯、利木赞、夏洛莱(法系)、德国黄牛4个品种牛,分别杂交西门塔尔杂种母牛,产犊后从每个杂交组合中选择11头断奶小公牛,在相同饲养管理条件下持续育肥至18月龄,并进行屠宰和肉质评定。结果表明:红安西杂组合杂交效果最好,其次是利西杂及夏西杂,德黄西杂组合杂交效果较差。说明在生产实际中,如果采用断奶小公牛持续育肥至18月龄时出栏、屠宰,应优先选择红安格斯×西门塔尔杂交组合。     

Aptitudes maternelles des races laitieres,mixtes, rustiques et a viande pour la production de veaux de boucherie par croisement industriel

The maternal values of various maternal dairy, local and beef breeds used in beef crossing are analyzed and compared on field progeny test data, including 374 Limousin, 94 Blond d'Aquitaine and 256 Charolais sires with, respectively: 16 765, 4 696 and 12 824 pure and cross-bred offsprings.The traits studied were female calving difficulty score and frequency, birth and 75-day weight, conformation score of calves and the product of the last two variables. Additive effects of the different dam breeds (13, 11 and 13 breeds, respectively mated to Limousin, Blond d'Aquitaine and Charolais sires) were estimated separately for each sire breed by the least squares method (taking into account sex and calving parity effects) and then expressed as deviations from the French Friesian estimate.On score and frequency of calving difficulties, dam breeds were classed in the following groups (from best to worst): (1) Aubrac, Tarentaise; (2) Salers, Gasconne, Abondance, Montbéliarde; (3) Charolaise, Normande, Brune des Alpes, Limousine; (4) Frisonne, Blonde d'Aquitaine, Pie-Rouge de l'Est. Rating on 75-day weight and postnatal growth showed a superiority of dairy breeds over beef and local breeds which is more pronounced when the potential growth of the sire breed is high. The conformation score clearly distinguishes beef, dual-purpose, dairy and local breeds in decreasing order of merit while this ranking remains unchanged for beef synthetic value when dam breeds are crossed with Limousin and Blond d'Aquitaine sires. Large-size dairy breeds such as Pie-Rouge de l'Est, Brune des Alpes and Normande crossed with Charolais permit a better expression of potential growth in the calves.These results show that the utilization of suckling dam breeds in crossing with paternal beef breeds involves complementarity between maternal and paternal components in order to obtain optimum balance between size, growth traits (growth potential, milk production) and muscular conformation.     

利木赞、夏洛来改良大别山牛育肥效果观察

[目的]探索肉牛改良大别山牛的育肥效果。[方法]从大别山黄牛及其与利木赞和夏洛来的杂交牛中分别选择体重150 kg左右的育肥牛各6头;均饲喂我们设计的同一饲料配方日粮,预试期同健胃驱虫法处理。[结果]在日常饲养管理相同的情况下,经30 d观察记载,大别山黄牛日增重0.46 kg、利杂牛日增重0.99 kg、夏杂牛日增重1.28 kg;两种杂交牛分别比大别山黄牛提高115.22%和178.26%。[结论]每增重1 kg毛重,大别山黄牛需精饲料5.43kg;而利杂牛和夏杂交牛只需要2.85 kg和2.38 kg。     

Genetic diversity analyses of 10 indigenous Chinese pig populations based on 20 microsatellites

To study the genetic diversity of Chinese indigenous pig breeds, a total of 403 pigs from 10 local populations and 1 exotic Duroc breed were genotyped for 20 microsatellite markers. Heterozygosity and Wright's F-statistics (F(IS), F(ST), and F(IT)) were calculated to determine the genetic variation in those populations. The observed heterozygosities were in the range of 0.31 (Duroc) to 0.66 (Shengxian). The F(IS) value was in a range of -0.07 to 0.48. The mean F(ST) showed that approximately 78% of the genetic variation was within-population and 22% was across the populations. The 10 Chinese local breeds were classified into two major groups according to the phylogenetic tree, which was based on standard genetic distance. Four pig populations, Jianli, Ganxi Two Ends Black, Shaziling, and Dongshan were grouped into one branch. Before the study, these four populations were all classified as Central China Two Ends Black according to coat color, shape of the head, and shape of the ear. The Jinhua pig, which also has the two-ends-black coat color, was also grouped to the same branch but was not traditionally classified into this type. The five populations were located in various provinces in central China. The other five populations, Nanyang Black, Hainan Spotted, Huainan Black, Jiaxing Black, and Shengxian Spotted (black body, white feet), were grouped into another branch. The two groups of pig breeds had the same F(ST) value (0.14) when calculated separately. This value was similar to that of Iberian pigs (0.13) but smaller than that of the European pigs (0.27) as reported by other researchers. Our study showed that large genetic differentiation exists in Chinese pig breeds. The grouping of the five two-ends-black populations into one branch of the phylogenetic tree may indicate that the number of conservation farms can be decreased for this type of pig.     

营养水平对杂交肉牛FABP3基因表达及IMF的影响

为研究营养水平对杂交肉牛心脏型脂肪酸结合蛋白（FABP3）基因表达及肌内脂肪含量（IMF）的影响,以西门塔尔、利木赞和夏洛莱杂交肉牛为研究对象,利用实时荧光定量PCR技术,分别测定高、中、低营养水平的3种杂交肉牛背部脂肪中FABP3mRNA表达水平,并测定其背最长肌IMF。结果：（1）高营养组中夏洛莱牛IMF高于同营养组其他2种肉牛,其背部脂肪中FABP3mRNA水平也显著高于另外2种杂交肉牛（P〈0.01）;中营养组中西门塔尔和利木赞牛IMF均高于同营养组的夏洛莱牛,但FABP3mRNA的水平无显著差异（P〉0.05）;低营养组中夏洛莱牛IMF和FABP3mRNA水平均显著低于另外2种肉牛（P〈0.01）;（2）夏洛莱杂交肉牛背部脂肪中FABP3mRNA水平与IMF具有显著的相关性（P〈0.05）,而西门塔尔和利木赞牛中FABP3mRNA水平与IMF无显著相关性（P〉0.05）。该结果表明提高营养水平影响FABP3mRNA表达并在一定程度上影响IMF,但影响显著与否存在品种差异,在肉牛育种和牛肉生产中应当同时考虑营养因素和遗传因素。     

贵州不同三元杂交肉牛生长性能比较

为了筛选适合贵州生产的三元杂交肉牛,试验选用利木赞牛、安格斯牛和夏洛莱牛冻精对西本母牛进行杂交改良.试验结果表明：不同杂交组合后代犊牛均表现出明显的杂种优势,从初生到18月龄,夏西本牛的体重、体尺指标均最优,依次为利西本牛、安西本牛、西本杂牛;3组三元杂交牛不同月龄的体重、体尺指标均差异不显著（P＞0.05）,但均显著高于西本杂牛（P＜0.05）.结论：虽然夏西本牛的体尺指标和生产性能最好,但由于其产犊难产比例较高,且当地养殖户不喜欢其白色的被毛,因此建议在本省推广利西本牛、安西本牛.     

Inbreeding trends and pedigree analysis of Irish dairy and beef cattle populations

The objective of this study was to determine the inbreeding levels and to analyze the pedigree of Irish purebred populations of Charolais, Limousin, Hereford, Angus, and Simmental beef cattle, as well as the Holstein-Friesian dairy breed. Pedigree analyses included quantifying the depth of known pedigree, average generation intervals, effective population size, the effective number of founders, ancestors, and founder genomes, as well as identifying the most influential animals within the current population of each breed. The annual rate of increase in inbreeding over the past decade was 0.13% (P < 0.001) in the Hereford, 0.06% (P < 0.001) in the Simmental, and 0.10% (P < 0.001) in the Holstein-Friesian breeds. Inbreeding in the other breeds remained relatively constant over the past decade. Herefords had the greatest mean inbreeding in 2004, at 2.19%, whereas Charolais had the lowest, at 0.54%. Over half of each purebred population in 2004 was inbred to some degree; the population with the greatest proportion of animals inbred was the Hereford breed (85%). All 6 breeds displayed a generation interval of approximately 6 yr in recent years. In the pure-bred females born in 2004, the 3 most influential animals contributed between 11% (Limousin) and 24% (Hereford) of the genes. Effective population size was estimated for the Hereford, Simmental, and Holstein-Friesian only, and was 64, 127, and 75, respectively. The effective number of founders varied from 55 (Simmental) to 357 (Charolais), whereas the effective number of ancestors varied from 35 (Simmental and Hereford) to 82 (Limousin). Thus, despite the majority of animals being inbred, the inbreeding level across breeds is low but rising at a slow rate in the Hereford, Simmental, and Holstein-Friesian.     

不同品种牛背最长肌抗氧化性能的研究

本试验旨在研究不同品种牛肌肉的抗氧化特性,为优质牛肉的生产提供试验数据。选用5个品种牛(利木赞牛、中国西门塔尔牛、鲁西牛、秦川牛、晋南牛)的背最长肌,测定肌内脂肪含量、24小时的滴水损失以及在0～4℃下肉色、过氧化物值(PV)及硫代巴比妥酸反应物(TBARS)在72h内的变化动态。结果表明,背最长肌的肌内脂肪含量与24小时滴水损失率在不同品种牛肌肉之间没有显著差异(P>0.05);在整个储存时期(0～72h),5个品种牛肌肉的a*、b*值均呈下降趋势;4～72h内,利木赞牛肌肉的a*值均是最高的,且在冷藏8、12h时,利木赞牛肌肉的a*值显著大于鲁西牛肉和秦川牛(P<0.05),24h后利木赞牛的a*值显著大于西门塔尔牛(P<0.05);随着储存时间的延长,5个品种牛背最长肌的PV和TBARS值均有不同程度的增加,利木赞牛肌肉的PV和TBARS值增加最慢,秦川牛和鲁西牛肌肉的PV和TBARS值增加较快。结果表明,5个品种牛的肌内脂肪含量和滴水损失差异不显著,利木赞牛肌肉能够较长时间保持肉色和抗氧化特性。     

杂交方式对肉牛产肉性能的影响

从1985起，系统性的选择了国外8个优良肉牛品种西门塔尔、利木赞、夏洛莱、皮埃蒙特牛等的冻精，采用级进和多元杂交的方式，产生了14个不同的肉牛杂交组合，用统一的方案进行了肥育、屠宰试验，研究了不同杂交方式对产肉性能的影响，为现阶段加速发展肉牛产业提供科学依据。     

Therapy of hypodermyiasis in heifers from the economic point of view]

The test set of animals consisted of sixty one- to two-year-old heifers of the Slovak Spotted and Pinzgau breeds kept at three sites. The Hypocid preparation (containing 40% trichlorphon) in the dose of 15 ml per 100 kg of live weight was applied to these cows by the lavage method in the sacrolumbar region of the spine in 1973. Another group, consisting of 58 heifers, was left untreated as controls. In the experimental period extending over 158, 150 and 120 days at different sites (143 days on an average), weight gains and the health condition of the experimental and control animals were checked in monthly intervals. The average extensity of invasion in the control heifers was 79.31% and the intensity of invasion was 14.58%. The extenseffectiveness of Hypocid (EE) was 97.90% and the intenseffectiveness of the preparation (IE) was 99.99%. The results prove a negative effect of hypodermatosis on the weight gains of untreated heifers and high profitability of the therapy: after subtraction of the costs of therapy the savings were 1.74, 3.88 and 2.25 crowns per kg gain per day (2.62 crowns on an average). The veterinary measures gave the following savings per each crown expended: 2,243.55; 3,066.85 and 922.83 crowns (depending on site).     

Genetic characterization of the Blonde d'Aquitaine cattle breed using microsatellite markers and relationship with three other French cattle populations

This study was conducted to evaluate the genetic diversity of Blonde d'Aquitaine, a well-muscled native French beef breed, and to understand the relationships between Blonde d'Aquitaine, Limousin and Salers. We also compared these three beef breeds to the Holstein dairy breed. For this purpose, a set of 16 microsatellite markers were investigated. The obtained results show that Blonde d'Aquitaine has a high level of genetic diversity. Our study shows also that the French beef breeds have genetic differentiation among them, with approximately 9% of the total variation owing to breed differences. Our results show also that Blonde d'Aquitaine and Salers populations are genetically more similar to each other than to the Limousin.