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Plasma melatonin levels in relation to the light-dark cycle and parental background in domestic pigs
Andersson H 《Acta veterinaria Scandinavica》2001,42(2):287-294
To study porcine melatonin secretion in a stable environment 3 daytime (10.00-15.00) and 3 nighttime (22.00-03.00) plasma samples were collected by jugular venipuncture from 15 gilts, 16 sows, 3 boars and 48 piglets (24 females and 24 males from 8 litters) and analysed for melatonin content. Nighttime melatonin concentrations were higher than daytime melatonin concentrations (p < 0.001), whereas no effect of sampling order could be discerned. The 3 adult Hampshire boars had higher melatonin concentrations during the day and the night, than the 31 adult Yorkshire females (p < 0.05). There was no clear difference between gilts and sows in plasma melatonin. The gilts from one of the litters had higher plasma melatonin concentrations than the gilts in 3 other litters (p < 0.05). Among the 48 piglets, the increase of nocturnal melatonin secretion differed between litters (p < 0.01), whereas the influence of father was not quite significant (p = 0.12). No difference in daytime melatonin concentrations between litters could be found, and there was no difference in melatonin levels between the male and female piglets. In conclusion, this study demonstrates that domestic pigs express a nocturnal increase of melatonin secretion in a standard stable environment. For some animals the amplitude of nighttime melatonin secretion was very low, although always higher than the daytime base levels. Furthermore, the levels of nighttime melatonin secretion differed between litters, which suggests a genetic background. 相似文献
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应用SSR分子标记,对河南省15个居群共288份狗牙根材料进行遗传多样性及群体遗传结构分析,结果表明,10对引物共扩增出173条条带,其中163条为多态性条带,多态性条带百分率为94.29%,表明河南省狗牙根具有丰富的多态性。15个居群间的遗传分化系数为0.3857,即发生在居群间的遗传变异达到38.57%,大部分的遗传变异发生在居群内部,居群间基因流为0.7964,居群之间存在一定程度的基因交流。不同居群间遗传一致度的变化范围是0.746~0.964,平均为0.767。15个居群间的UPGMA聚类分析结果表明居群间没有完全按照地理来源进行聚类,遗传距离和地理距离矩阵之间的Mantel检验结果表明狗牙根居群间的遗传距离与地理距离之间无相关性。288份狗牙根材料之间的遗传距离为0.0173~0.5205,平均为0.3113,UPGMA聚类结果将所有材料分为3组。基于Structure软件的群体遗传结构分析结果表明,可将288份狗牙根材料分为2个亚群和一个混合型群体,与288份材料的UPGMA聚类结果基本一致,由此可判断两个亚群的遗传背景单一,混合型群体存在一定的种质基因渗透,遗传背景较为复杂。 相似文献
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我国主要地方绵羊品种遗传亲缘关系 总被引：12，自引：0，他引：12
利用 10种 10碱基的随机引物 ,分析了我国 8个地方绵羊品种计 88只绵羊的随机扩增多态 DNA。结果表明 ,我国地方绵羊品种基因组 DNA多态位点百分率为 81.36 % ,群体平均遗传多样性指数为 1.3370 ,具有丰富的群体遗传多样性。但滩羊、小尾寒羊、藏绵羊和蒙古羊群体遗传多样性程度较低 ,应加强保种措施。群体遗传分化指数为0 .9172 ,说明遗传变异主要存在于群体间。品种间的分子聚类关系基本上反映了品种间的遗传亲缘关系 ,与品种的形成历史及我国地方绵羊的起源进化学说基本一致 ,具有相同来源的蒙古羊、乌珠穆沁羊、小尾寒羊和湖羊的分子聚类关系表明 ,4个地方绵羊品种间已经有了明显的遗传分化 ,小尾寒羊、乌珠穆沁羊间遗传分化较低 ,湖羊与蒙古羊之间相对较高 ,而小尾寒羊和乌珠穆沁羊与湖羊和蒙古羊之间的遗传分化最高 相似文献
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论文从分子遗传学的角度对鸭的遗传资源在群体遗传多样性、群体起源、进化及构建遗传图谱等多个方面的评估进行综述,并对分子遗传标记技术在鸭遗传资源的保护利用上的应用进行概述,以期通过现代动物分子育种技术加快鸭的育种进程。 相似文献
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42份紫花苜蓿种质资源遗传多样性的SSR分析 总被引：1，自引：0，他引：1
为了补充现有苜蓿(Medicago sativa)种质资源的遗传多样性信息,采用SSR分子标记技术对1份野生紫花苜蓿种质和41份栽培紫花苜蓿品种的遗传多样性进行了研究。15对引物在供试苜蓿材料中共获得231条扩增带,其中163条具有多态性。引物的多态位点百分率、Nei’s基因多样性指数和Shannon信息指数的平均值分别为71.55%、0.210 0和0.326 3。供试材料间的相似系数介于0.641~0.913,平均为0.791,栽培品种间的平均相似系数相对较大,野生种质资源与栽培品种间的平均相似系数相对较小。聚类分析表明,供试材料在相似系数0.778处可聚为五大类,单独聚为类的陇东野生紫花苜蓿、CW 200和CW 787都表现出了与其他材料间较远的亲缘关系。基于主成分分析图,可把供试材料分为四大类,其中第Ⅰ、Ⅱ类与第Ⅲ、Ⅳ类材料间的亲缘关系较远。综上,供试苜蓿种质资源具有较丰富的遗传多样性,部分种质资源表现出了相对独立的遗传特性。 相似文献
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随着萨福克羊、杜泊羊、澳洲美利奴羊等国外优良绵羊品种的大量引进,显著提高绵羊生产性能的同时,其携带的各种遗传缺陷病在全国范围内快速蔓延,这将给羊产业带来巨大的经济损失,严重威胁我国绵羊育种和羊业的健康发展.近年来,发达国家通过对种羊进行遗传缺陷病基因诊断进行遗传净化,而我国相关工作尚处于起步阶段.文章就皮肤脆裂症、羔羊蜘蛛综合症和致死型短颌-心脏扩大-肾发育不全综合症等单基因遗传缺陷病的遗传基础、临床症状和检测方法研究进展进行了综述,以期为我国绵羊遗传缺陷病净化提供理论借鉴. 相似文献
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甘肃红砂不同种群遗传多样性的ISSR分析 总被引：4，自引：1，他引：3
本实验采用ISSR分子标记技术,对甘肃地区5个种群共50个单株的红砂遗传多样性水平和遗传结构进行了研究。通过实验,从50个引物中筛选出12个重复性高,条带清晰的引物。12条引物共检测到69个位点,其中多态位点有60个,多态位点比率(P)为86.96%。用MarkerⅢ作为分子量标准,检测到甘肃红砂PCR产物的分子量在500～3 000 bp。应用遗传多样性分析软件Popgen 32 进行分析计算得出:在物种水平上,Shannon多样性指数(I)为0.542 9,Nei基因多样性指数(H)为0.379 0;基因分化系数Gst为0.096 4,基因流Nm为4.685 1,表明甘肃红砂种群遗传分化大部分存在于种群内。在种群水平上, I为0.489 3,H为0.342 4。P、H及I都表明甘肃红砂种群具有较高的遗传多样性。聚类分析还表明甘肃红砂种群的遗传距离与地理距离之间无显著的相关性;甘肃红砂遗传多样性与其本身特性和所处不同种群有关。 相似文献
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川渝部分山羊品种(类群)遗传多样性微卫星标记研究 总被引：1，自引：0，他引：1
为分析川渝山羊品种(类群)的遗传多样性和系统发生关系,利用30个微卫星标记,对6个山羊品种(类群)进行分析。结果表明:金堂黑山羊遗传多样性最丰富,群体多态信息含量、平均杂合度和有效等位基因数分别为0.777、0.819和6.54;大足黑山羊各项指标最低,分别为0.736、0.787和5.57。对6个品种(类群)聚类分析表明,金堂黑山羊与南江黄羊的首先聚类在一起,然后依次与板角山羊、川东白山羊、大足黑山羊和波尔山羊聚类。各山羊品种(类群)的聚类关系与其来源、育成史及地理分布基本一致。 相似文献
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利用１５对ＳＳＲ引物和１０个ＩＳＳＲ引物对紫花苜蓿复合体３个种黄花苜蓿、多变苜蓿及紫花苜蓿共１０个居群的遗传多样性及亲缘关系进行研究。结果表明,ＳＳＲ标记下,１０个居群中多变苜蓿ＶＧ 居群多态位点百分率、Ｓｈａｎｎｏｎ信息指数及Ｎｅｉ’ｓ基因多样性指数均最高;ＩＳＳＲ标记下,黄花苜蓿ＦＨ居群以上３个指数均最高;黄花苜蓿居群ＦＨ在２种分子标记下都存在特有位点。说明在１０个居群中多变苜蓿居群ＶＧ与黄花苜蓿居群ＦＨ表现出较丰富的遗传多样性,值得进一步保护。ＵＰＧＭＡ聚类分析结果表明,在２种分子标记下３个种可以被有效区分,结合它们在新疆境内的分布,本研究支持仍将紫花苜蓿、黄花苜蓿和多变苜蓿划分为３个种。 相似文献
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A.C. Acosta O. Uffo A. Sanz R. Ronda R. Osta C. Rodellar I. Martin‐Burriel P. Zaragoza 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2013,130(1):79-86
Conservation and improvement strategies in farm animals should be based on a combination of genetic and phenotypic characteristics. Genotype data from 30 microsatellites were used to assess the genetic diversity and relationships among five Cuban cattle breeds (Siboney de Cuba, Criollo Cubano, Cebú Cubano, Mambí de Cuba and Taíno de Cuba). All microsatellite markers were highly polymorphic in all the breeds. The expected heterozygosity ranged from 0.67 ± 0.02 in the Taíno de Cuba breed to 0.75 ± 0.02 in the Mambí de Cuba breed, and the observed heterozygosity ranged from 0.66 ± 0.03 in the Cebú Cubano breed to 0.73 ± 0.02 in the Siboney de Cuba breed. The genetic differentiation between the breeds was significant (p < 0.01) based on the infinitesimal model (FST). The exact test for Hardy‐Weinberg equilibrium within breeds showed a significant deviation in each breed (p < 0.0003) for one or more loci. The genetic distance and structure analysis showed that a significant amount of genetic variation is maintained in the local cattle population and that all breeds studied could be considered genetically distinct. The Siboney de Cuba and Mambí de Cuba breeds seem to be the most genetically related among the studied five breeds. 相似文献
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Mtileni BJ Muchadeyi FC Maiwashe A Groeneveld E Groeneveld LF Dzama K Weigend S 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2011,128(3):209-218
In this study, we compare the level and distribution of genetic variation between South African conserved and village chicken populations using microsatellite markers. In addition, diversity in South African chickens was compared to that of a reference data set consisting of other African and purebred commercial lines. Three chicken populations Venda, Ovambo and Eastern Cape and four conserved flocks of the Venda, Ovambo, Naked Neck and Potchefstroom Koekoek from the Poultry Breeding Resource Unit of the Agricultural Research Council were genotyped at 29 autosomal microsatellite loci. All markers were polymorphic. Village chicken populations were more diverse than conservation flocks. structure software was used to cluster individuals to a predefined number of 2 ≤ K ≤ 6 clusters. The most probable clustering was found at K = 5 (95% identical runs). At this level of differentiation, the four conservation flocks separated as four independent clusters, while the three village chicken populations together formed another cluster. Thus, cluster analysis indicated a clear subdivision of each of the conservation flocks that were different from the three village chicken populations. The contribution of each South African chicken populations to the total diversity of the chickens studied was determined by calculating the optimal core set contributions based on Marker estimated kinship. Safe set analysis was carried out using bootstrapped kinship values calculated to relate the added genetic diversity of seven South African chicken populations to a set of reference populations consisting of other African and purebred commercial broiler and layer chickens. In both core set and the safe set analyses, village chicken populations scored slightly higher to the reference set compared to conservation flocks. Overall, the present study demonstrated that the conservation flocks of South African chickens displayed considerable genetic variability that is different from that of the assumed founder populations (village chickens). 相似文献
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Estimating genetic connectedness among herds is important for the accuracy of dairy cattle genetic evaluation. When selecting between animals raised in different herds, the accuracy of their genetic evaluations can be influenced by the degree of connectedness among these herds. In this study, two methods were used to measure genetic connectedness, CR （genetic connectedness rating ） and GLt （total number of direct genetic links between group）, among herds from Beijing, Shanghai, and Tianjin. Genetic connectedness between the herds from Beijing and Tianjin was 23.95%, between Beijing and Shanghai was 17. 10%, and between Shanghai and Tianjin it was 14.28%. Genetic connectedness between herds from Beijing and Tianjin was the highest and that between Shanghai and Tianjin was the lowest. The correlation coefficient for the two methods was 0. 808. Some suggestions for improved genetic evaluation of dairy cattle were also discussed. 相似文献
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采用ISSR分子标记对10个歪头菜自然居群的104个样本进行遗传多样性分析,筛选的10条ISSR引物共扩增出115个位点,其中多态性位点110个。在物种水平上多态性比率(PPB)为95.65%,在居群内多态位点比率为24.35%~49.70%。POPGENE分析结果显示,物种水平上Nei’s 基因多样性(H)为0.2632,Shannon’s遗传多样性信息指数(I)为0.4046,基因流(Nm)为0.4553,基因分化度(Gst)为0.5283,AMOVA分析居群间遗传分化程度为50.51%。研究表明,10个采样点的歪头菜在物种水平上具有较高的遗传多样性,但在居群之间已经出现了一定程度的遗传分化,且居群间的遗传分化程度高于居群内的分化程度。同时,证明了环境压力大小对于遗传多样性的高低具有选择作用,环境压力小的烟台和环境压力大的合作地区具有较高的遗传多样性,但环境压力介于二者之间的地区遗传多样性水平相对较低。本研究结果不仅对于了解歪头菜遗传进化和其生长地的环境的关系具有重要的参考价值,对合理利用歪头菜遗传资源及育种还具有非常重要的作用。 相似文献
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本研究采用ISSR分子标记技术分析了甘肃省4个地区(合作、碌曲、阿万仓和阿孜)钝裂银莲花的11个居群的遗传多样性水平和遗传结构。结果表明,13个引物共扩增出701条带,其中392条具有多态性,多态位点百分率为55.92%。在物种水平上,Shannon多样性指数(I)为0.372,Nei基因多样性指数(H)为0.250;Nei的基因分化系数Gst和AMOVA分析表明钝裂银莲花居群遗传分化大部分存在于居群间。在居群水平上,I为0.183,H为0.114,可见钝裂银莲花居群具有较高的遗传多样性。依据Nei的遗传距离对不同居群进行UPGMA聚类,聚类结果为合作居群为一类,碌曲和阿万仓居群为一类,阿孜为一类。居群遗传多样性与环境因子间的相关性分析表明,遗传多样性水平与海拔、含水量、有效磷和经纬度之间没有相关性,而与降水量之间显著负相关。 相似文献
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披碱草属种质资源研究进展 总被引：7，自引：3，他引：4
披碱草属Elymus牧草分布广泛,种类繁多,广义的披碱草属包括近150个种,而在我国,则比较接受狭义披碱草属的概念,即有12余种.披碱草属牧草为中生-旱中生多年生优良牧草,是草原和草甸的重要组成部分,饲用价值极高.该属是禾本科小麦族中非常重要的一个类群,它具有麦类作物所缺乏的抗病、抗虫、抗旱、耐盐等优良抗逆基因,是现代麦类育种的重要种质资源.在前人研究的基础上,对国内外披碱草属种质资源的系统学分类、分布情况、遗传多样性研究进行了总结和探讨,以期为披碱草属资源的进一步研究利用提供参考依据. 相似文献
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MyoD基因在不同猪种中的PCR-RFLP遗传多态性及其遗传效应研究 总被引：6，自引：2，他引：6
采用PCR—RFLP的方法分析了MyoD基因在10个中外猪种及部分杂交群体中的分布情况，并分析了MyoD基因对肌纤维、胴体品质、胴体等级性状和肉质性状的遗传效应。结果表明：MyoD基因内含子1内的DdeI酶切位点多态性较丰富。在多数地方猪种群体中，C基因的分布具有绝对优势，且主要以杂合子AC形式存在。突变型A基因对胴体性状和胴体等级性状的影响较大，可极显著地增加胴体瘦肉率和眼肌面积，降低皮脂含量，提高腿臀比例，增加胴体长度（P〈0．01），同时会降低猪肉品质。具体讲，A基因对增加肌纤维面积的加性效应值和显性效应值分别为457．915μm^2和431．055μm^2；对增加嗣体瘦肉率的加性效应值和显性效应值分别为3．594％和-0．153％；对增加眼肌面积的加性效应值和显性效应值分别为3．084cm^2和-0．46cm。；对皮脂率的加性效应值和显性效应值分别为～3．916％和0．666％；对提高腿臀比的加性效应值为0．771％，显性效应值为0．068％。A基因对屠宰后45min和冷藏24h后的肉色评分的加性效应值分别为-0．145和-0．160，显性效应值分别为-0．052和-0.213． 相似文献
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Genetic analysis of twinning rate and milk yield using a threshold‐linear model in Japanese Holsteins 
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下载免费PDF全文 The objective of this study was to estimate genetic parameters and breeding values for the twinning rate of the first three parities (T1, T2 and T3) and 305‐day milk yield in first lactation (MY), using a four‐trait threshold‐linear animal model in Japanese Holsteins. Data contained 1 323 946 cows calving between 1990 and 2007. Twinning was treated as a binary character: ‘single’ or ‘twin or more’. Reported T1, T2 and T3 were 0.70%, 2.87%, and 3.73%, respectively. Individual 305‐day milk yield was computed using a multiple trait prediction for cows with at least eight test‐day records. (Co)variance components were estimated via Gibbs sampling for randomly sampled subsets. Posterior means of heritabilities for T1, T2 and T3 were 0.11, 0.16 and 0.14, respectively. Genetic correlations between parities were 0.92 or greater. Genetic correlations of MY with twinning rate were not ‘significant’ (i.e. their 95% highest probability density intervals contained zeros). Multiple births at different parities were considered as the same genetic trait. The average evaluations of T1 (T2) for sires born before 1991 was 0.48% (2.25%) compared with a mean of 0.76% (3.37%) for sires born after 1992. A recent increase in the reported twinning rate reflects the positive genetic trend for sires in Japanese Holsteins. 相似文献