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1.
From approximately 1000 papers with data on protein polymorphism in some 216 breeds of cattle, 10 polymorphic proteins were compared in means and variances of gene frequencies (arcsin p 1/2) for ten well-recognized breed groups for 196 of the breeds. The polymorphic proteins were alpha-lactalbumin, beta-lactoglobulin, caseins (alpha s1, beta and chi), serum albumin, transferrin, haemoglobin, amylase I and carbonic anhydrase II. The breed groups were North European, Pied Lowland, European Red brachyceros, Channel Island brachyceros, Upland brachyceros, primigenius-brachyceros mixed, primigenius, Indian Zebu, African Humped (with Zebu admixture), and African Humped (Sanga). The coherence within groups and the differences between groups are often impressive. Only carbonic anhydrase II fails to differentiate at least some of the major breed groups. In some cases paradoxical distributions of rare genetic variants can be explained by a more detailed inspection of breed history. The chemical data support the morphological and geographical divisions of cattle into major breed groups. There are three distinct but related brachyceros groups; for some polymorphisms the two Channel Island breeds, the Jersey and the Guernsey, are quite divergent. Although some authorities have considered the Pied Lowland as primigenius, it is a very distinct breed group.  相似文献   

2.
Genetic deversity at the highly polymorphic BoLA-DRB3 locus was investigated by DNA sequence analyses of 18 African cattle from two breeds representing the two subspecies of cattle, Bos primigenius indicus and Bos primigenius taurus. Yhe polymorphism was compared with that found in a sample ofd 32 European cattle from four breeds, all classified as B. p. taurus. Particularly extensive genetic diversity was found among African cattle, in which as many as 18 alleles were recognized in this small random sample of animals from two breeds. The observed similarity in allele frequency distribution between the two African populations, N'Dama and Zebu cattle, is consistent with the recent recognition of gene flow between B. p. indicus and B. P taurus cattle in Africa. A total of 30 DRB3 alleles were documented and as many as 26 of these were classified as major allelic types showing at least five amino acid substitutions compared with other major types. The observation of extensive genetic diversity at MHC loci in cattle, as well as in other farm animals, provides a compelling argument against matin-type preferences as a primary cause in maintaining major histocompatibility complex diversity, since the reproduction of these animals has been controlled by humans for many generations.The nucleotide sequence data reported in this paper have been submitted to the EMBL nucleotide sequence database and have been given the accession numbers X87641-X87670  相似文献   

3.
It has been claimed that the origin of the South Devon breed of cattle is 'unknown' and that biochemical polymorphisms '… indicate that Gelbvieh and South Devon had a common ancestry on the Continent and are distinct from other British breeds such as Hereford, Angus and Jersey' (Kidd et al., 1974).
In fact, historical records indicate that the South Devon evolved largely from native Devon cattle and is a close relative of other English Lowland breeds such as the North Devon and Hereford. Information about crosses from other breeds makes no mention of the Gelbvieh but emphasises the contribution of Channel Island breeds, especially the Guernsey. Data for biochemical polymorphisms in the relevant breeds show agreement with the historical information and with the biogeography of the breeds involved.  相似文献   

4.
It has been claimed that the origin of the South Devon breed of cattle is 'unknown' and that biochemical polymorphisms '. . . indicate that Gelbvieh and South Devon had a common ancestry on the Continent and are distinct from other British breeds such as Hereford, Angus and Jersey' (Kidd et al., 1974). In fact, historical records indicate that the South Devon evolved largely from native Devon cattle and is a close relative of other English Lowland breeds such as the North Devon and Hereford. Information about crosses from other breeds makes no mention of the Gelbvieh but emphasises the contribution of Channel Island breeds, especially the Guernsey. Data for biochemical polymorphisms in the relevant breeds show agreement with the historical information and with the biogeography of the breeds involved.  相似文献   

5.
We pool three previously published data sets and present population genetic analyses of microsatellite variation in 48 Bos taurus cattle breeds from a wide range of geographical origins in Eurasia, mostly its northern territory. Bayesian model‐based clustering reveals six distinct clusters: besides a single‐population cluster of the Yakutian Cattle from Far Eastern Siberia and a cluster of breeds characteristic of an early origin, the other four major clusters largely correspond to previously defined morphological subgroups of Red Lowland, Lowland Black‐Pied, Longhorned Dairy and North European Polled cattle breeds. The results highlighted past expansion events of the productive breeds such as Danish Red, Angeln, Holstein‐Friesian and Ayrshire in northern and Eastern Europe. Based on genetic assignment of the breeds and the availability of breed information, we provide a preliminary classification of the five breeds that were to date undefined. Furthermore, in the analysis of molecular variance, despite some correspondence between geographical proximity and genetic similarity, the breed classification appears to be a better predictor of genetic structure in the cattle populations (the among‐group variance component: breed classification, 2.47%, P < 0.001; geographical division, 0.77%, P < 0.001).  相似文献   

6.
中国黄牛品种多样性及其保护   总被引:27,自引:1,他引:26  
总结关于中国黄牛起源和品种多样的文献,依据头颅骨分类,毛色,血液蛋白多态性,体型体态,梁色体组型,线粒体DNA和考古论证的资料可知,在各地的牛种中,中国的无峰牛来自于两种原牛,在长城以北有长角型的普通牛的分支土雷诺蒙古利亚(truano-mognolia)和青藏高原有矮型的短角型普通牛(draft pimigenius),有峰牛来自于三种原牛,来自北非,西亚的瘤牛,印度瘤牛和东南亚瘤牛,这些牛的后裔大多以混血种形态存在,关中和中原地区牛受西亚瘤牛的影响,胸垂较发达,多皱折,体格圈套 ,云南部分高峰牛受印度瘤牛影响,东南地区高峰牛为古代准牛属爪哇牛被东南亚瘤牛吸收杂交的后裔,属矮小型,体躯体而皱折贫乏,肩峰属头位,耳端较尖而不下垂,在起源上,藏牛为原始种,海南高峰牛(zebu sinsis)为一个瘤牛的发源地,云南高峰牛是一个特殊种,击阳牛是含有非洲瘤牛血淮的特殊种,全国的黄牛在总体上可分为两大系统三大类型,根据体态特征分为无峰,低身和有峰三种,按地理分布为蒙古,黄淮和长珠三组,现代国民经济发展引进30个外国品种,加速了地方品种的灭绝,本文还提出了农牛保种应以特殊品种和边缘地区以及特有生态区牛种为主要的主张。  相似文献   

7.
Initially, domesticated African cattle were of taurine type. Today, we find both African Bos taurus and Bos indicus cattle, as well as their crossbreeds, on the continent of Africa and they all share the same set of African taurine mitochondrial DNA haplogroups. In this study, we report genetic variation as substitutions and insertions/deletions (indels) on both the X and Y chromosomes, and use the variation to assess hybridization between taurine and indicine cattle. Six African cattle breeds (four Sanga breeds, including Raya Azebu, Danakil, Caprivi, Nguni; and two Zebu breeds, including Kilimanjaro Zebu and South Kavirondo Zebu) were screened for six new X-chromosomal markers, specifically three single nucleotide polymorphisms and three indels in the DDX3X (previously DBX ) and ZFX genes, and five previously identified Y-chromosomal markers in the DDX3Y (previously DBY ) and ZFY genes. In total, 90 (57 bulls and 33 cows) samples from the African breeds were analysed. We identify five diagnostic haplotypes of indicine and taurine origins on both the X and Y chromosomes. For each breed, the level of indicine introgression varies; in addition to pure taurine, indicine and hybrid X-chromosome individuals, recombinant X-chromosome variants were also detected. These markers are useful molecular tools for assessing the level of indicine admixture in African cattle breeds.  相似文献   

8.
1. Four hundred and seventy-five animals of the Canchim breed from EMBRAPA-UEPAE de Sao Carlos were analyzed by starch gel electrophoresis. 2. Albumin, amylase, transferrins, carbonic anhydrase, hemoglobin and nucleoside phosphorylase gene frequencies were compared with the same frequencies in the foundation breeds, Charolais and Indubrazil. 3. Theoretical values obtained considering the 5/8 European, 3/8 Zebu admixture are near the means calculated from our results and data from literature.  相似文献   

9.
Genetic relationships among European cattle breeds   总被引:1,自引:0,他引:1  
Genetic relationships among 37 European cattle breeds were investigated using blood group and serum protein polymorphisms. The 18 859 animals included in the study represented a random sample from pedigree populations in the UK. Within-breed variation was estimated by average heterozygosity and number of alleles observed, and breed relationships were evaluated by genetic distance. Standard errors of the heterozygosity, number of alleles and genetic distance were obtained by bootstrapping. The significance of breed differences was tested using an exact test of differentiation. French, Italian and Channel Island breeds were found to have generally higher heterozygosities and a greater number of alleles than breeds from mainland Britain and North Europe. Genetic distances ranged between 0·011 (±0·005) and 0·309 (±0·071). Two major breed groups were identified; a group of French, Italian and Channel Island breeds together with the Simmental and Gelbvieh, and a second group consisting of the mainland British and North European breeds. The exact test of breed differentiation showed all breeds to be significantly different from one another ( P < 0·0001). Overall relationships among breeds reflected their geographical origin and common ancestry rather than the agricultural use for which the breeds have been selected.  相似文献   

10.
In the samples of Russian Ayrshire and Gorbatov Red cattle breeds, distribution of frequencies of prolactin (PRL) gene alleles generated due to the presence of polymorphic RsaI site in exon 3 were studied. In the breeds, the frequencies of the B allele of the PRL gene (with RsaI(+) site) detected by the PCR-RFLP method were 14.1 and 8.6%, respectively. In Black Pied, Ayrshire and Gorbatov Red cattle breeds, variation of the microsatellite dinucleotide repeat in the regulatory region of the gene PRL was also studied. Gorbatov Red breed was monomorphic at the microsatellite locus with the only allele 164 bp in length. Two alleles (164 bp and 162 bp) were detected in the other breeds studied. The frequencies of 164-bp allele of the microsatellite locus were 93.7 and 90.0% in Black Pied and Ayrshire breeds, respectively. In Gorbatov Red breed of dairy type with good beef qualities and low milk-fat yield, lower level of heterozygosity for PRL gene was demonstrated compared to Ayrshire and Black Pied breeds with high milk-fat yield. In three cattle breeds, higher mean estimate of polymorphism information content of PCR-RFLP in exon 3 (PIC = 0.21) was revealed compared with the same estimate (PIC = 0.09) for the microsatellite locus variability in the regulatory region of the PRL gene. Characteristics of allele B distribution of the PRL gene in the representatives of the Bovidae family are considered.  相似文献   

11.
The region of intron 2 of the SDF1 gene encoding a chemokine of the CXC subfamily has been resequenced in Galloway, Hereford, and Black Pied cattle. Five of the single-nucleotide polymorphisms (SNP) that were earlier detected by other authors in various breeds of cattle in North America (99C/G, 128T/C, 206C/T, 267C/G and 313C/T) have been found. The 270insC polymorphic marker has proved to be monomorphic in Russian cattle breeds. Hereford cattle significantly differ from Galloway and Black Pied cattle in the frequencies of some SNP variants and their combinations. The number of SNP combinations in Hereford and Galloway cattle exceeds that in Black Pied cattle.  相似文献   

12.
In the samples of Russian Ayrshire and Gorbatov Red cattle breeds, distribution of frequencies of prolactin (PRL) gene alleles generated due to the presence of polymorphic RsaI site in exon 3 were studied. In the breeds, the frequencies of the Ballele of the PRLgene (with RsaI(+) site) detected by the PCR–RFLP method were 14.1 and 8.6%, respectively. In Black Pied, Ayrshire and Gorbatov Red cattle breeds, variation of the microsatellite dinucleotide repeat in the regulatory region of the gene PRLwas also studied. Gorbatov Red breed was monomorphic at the microsatellite locus with the only allele 164 bp in length. Two alleles (164 bp and 162 bp) were detected in the other breeds studied. The frequencies of 164-bp allele of the microsatellite locus were 93.7 and 90.0% in Black Pied and Ayrshire breeds, respectively. In Gorbatov Red breed of dairy type with good beef qualities and low milk-fat yield, lower level of heterozygosity for PRLgene was demonstrated compared to Ayrshire and Black Pied breeds that have high milk-fat yield. In three cattle breeds, higher mean estimate of polymorphism information content of PCR–RFLP in exon 3 (PIC = 0.21) was revealed compared with the same estimate (PIC = 0.09) for the microsatellite locus variability in the regulatory region of the PRLgene. Characteristics of allele Bdistribution of thePRLgene in the representatives of the Bovidae family are considered.  相似文献   

13.
14.
测定了13个黄牛品种125个个体的线粒体D-loop区段的全序列,包括12个中国地方黄牛品种的123个个体和德国黄牛2个个体,并进行了分析。结果显示,共检测到93个变异位点,57个单倍型,平均核苷酸差异(average number ofnucleotide differences,k)为22.708,核苷酸多样度(nucleotide diversity,π)为0.0251±0.00479,单倍型多样度(haplotypediversity,Hd)为0.888±0.026,表明我国黄牛品种遗传多样性非常丰富。构建的Neighbor-Joining进化树显示这13个品种主要分成两大类型:普通牛和瘤牛;新发现的特殊类型Ⅲ只有一个西藏阿沛甲咂牛的个体,它与牦牛D-loop序列最相近,证明西藏地区的黄牛与牦牛之间存在基因渗入现象。普通牛和瘤牛在日喀则驼峰牛中占的比例分别是64.3%和35.7%,在阿沛甲咂牛中占的比例分别是50.0%和50.0%,证明了西藏的黄牛也有瘤牛类型。云南牛品种的单倍型非常丰富证明了云南在中国黄牛起源上的重要地位;在27个中国黄牛品种中(本研究11个品种以及GenBank上的16个品种)找到了中国瘤牛的核心单倍型i1,并且对它进行了讨论。同时证明了西藏瘤牛独立于中国瘤牛核心类群的特殊性。  相似文献   

15.
The region of intron 2 of the SDF1 gene encoding a chemokine of the CXC subfamily has been resequenced in Galloway, Hereford, and Black Pied cattle. Five of the single-nucleotide polymorphisms (SNPs) that were earlier detected by other authors in various breeds of cattle in North America (99C/G, 128T/C, 206C/T, 267C/G and 313C/T) have been found. The 270insC polymorphic marker has proved to be monomorphic in Russian cattle breeds. Hereford cattle significantly differ from Galloway and Black Pied cattle in the frequencies of some SNP variants and their combinations. The number of SNP combinations in Hereford and Galloway cattle exceeds that in Black Pied cattle.  相似文献   

16.
The polymorphism of 23 microsatellites in the four main cattle breeds in Belgium (Holstein Friesian, Belgian Blue, Belgian Red Pied and East Flemish) was analysed. Heterozygosity, polymorphism information content, the effective number of alleles, exclusion probability and the probability of genotypic identity for two random individuals were calculated for all microsatellites and all breeds. The Belgian Blue breed is generally a little less polymorphic in comparison with the other three breeds. Estimates of the genetic distances between these breeds confirmed the widely accepted proposition that the Belgian Blue is the most genetically distinct of these breeds. The three other breeds are likely to become one population, given current breeding strategies. Exclusion probabilities in parentage control cases are >0·9999 in all four breeds when all 23 microsatellites are used and >0·98 with only the two most polymorphic multiplexes.  相似文献   

17.
Haemoglobin polymorphism in Brahman cattle and seven Southern African cattle breeds was investigated by means of starch gel electrophoresis. A difference was found between the migration rates of the Hb C of Brahman cattle and that of the indigenous Southern African cattle breeds, showing that these are actually two separate variants. We suggest that the faster migrating type, which occurs in Brahman cattle, should be called Hb C, while the slower migrating type of the Southern African breeds, should be called Hb I.
A comparison of the migration of the α and β chains of all the variants we encountered, including foetal haemoglobin, was carried out by means of starch gel electrophoresis in urea at acid and alkaline pH levels. Evidence was found of a difference in mobility of the non-a chains of haemoglobin A, B, C, I and F at different pH levels while no difference was detected in the migration rate of their respective α chains. These results confirm the theory that genetic variation is restricted to the non-α chain of bovine haemoglobin.
Progeny studies on 225 families confirm that the Hb I variant is allelic to Hb A and Hb B variants. The gene frequencies have been calculated on the basis that Hb I and Hb C are allelic at the β locus. The distribution of the different phenotypes is in accordance with this theory, assuming that the populations obey Hardy-Weinberg equilibrium.  相似文献   

18.
Many local livestock breeds in developing countries are being replaced by exotic breeds, leading to a loss of genetic resources. In southern Mali, for the past two decades, a trend towards increasing crossbreeding between the trypanotolerant N’Dama cattle and the trypano-susceptible Fulani Zebu cattle has been taking place. A survey with 160 farmers owning a cattle herd was carried out in southern Mali to investigate their production objectives, as well as trait and breed preferences and correlated socio-economic determinants in order to understand farmers’ breeding decisions and to identify comparative advantages of three breed groups (N’Dama, Fulani Zebu and crossbreds) raised in the study area. Data were analyzed using an exploded logit model. The reasons for raising cattle, as well as trait and breed preferences reflected the multiple objectives of the farmers. Draught power and savings were the most important production objectives. Productive traits were ranked highest; farmers reported large body size as the most preferred trait, followed by fertility, draught ability and milk yield. Crossbreds were the favored breed group. Breed preferences were mainly explained by ‘resistance to disease’ for N’Dama cattle and ‘high market price’ for Fulani Zebu and crossbred cattle. Production objectives, trait and breed preferences were mainly influenced by farmer group (local farmers and settled transhumants). Local farmers put comparatively more emphasis on livestock functions linked to crop production such as draught power. They had a higher preference for traction ability as a selection trait and preferred N’Dama over Fulani Zebu cattle. Settled transhumants emphasized milk yield as a selection trait and preferred Fulani Zebu over N’Dama. The results indicate that the trend towards more crossbreeding will continue putting the N’Dama breed under high risk of genetic dilution in southern Mali. The N’Dama cattle remain a valuable breed due to their adaptive traits such as disease and drought tolerance and their good traction ability, fulfilling the diverse objectives of local farmers. Crossbreeding was found to be a promising breeding strategy, which might contribute to the maintenance of the local breed, provided that breeding schemes are thoroughly planned and organized.  相似文献   

19.
Summary. Class II genes of the bovine major histocompatibility complex (MHC) were investigated by Southern blot analysis using human cDNA probes for DQα, DQβ, DRβ and DRβ. The presence of a DQ-like and a DR-like subregion in cattle was clearly indicated. Highly polymorphic restriction fragment patterns were obtained when genomic DNA, digested with any one of the Bam HI, Eco RI or Pvu II restriction enzymes, was hybridized with the DQα and the DQβ probe. The polymorphisms were interpreted genetically by analysing five paternal half-sib families of the Swedish Red and White breed. The material comprised, besides the bulls, 28 offspring and their dams. The analysis resolved 9 and 12 allelic variants of DQα and DQβ respectively. Thus, this investigation establishes a method for routine typing of MHC class II gene polymorphism in cattle. The results were entirely consistent with close linkage of DQα and DQβ since no recombinant was found and since alleles at these loci occurred in complete linkage disequilibrium in the material investigated. Close linkage between DQ and the blood group locus M, which has previously been found to be closely linked to the serologically defined BOLA-A locus, was also indicated. In this study DNA was isolated from frozen semen samples of dead bulls, which shows that this type of analysis will be useful in genetic investigations in cattle breeds, where artificial insemination is practised.  相似文献   

20.

Background

American Creole cattle presumably descend from animals imported from the Iberian Peninsula during the period of colonization and settlement, through different migration routes, and may have also suffered the influence of cattle directly imported from Africa. The introduction of European cattle, which began in the 18th century, and later of Zebu from India, has threatened the survival of Creole populations, some of which have nearly disappeared or were admixed with exotic breeds. Assessment of the genetic status of Creole cattle is essential for the establishment of conservation programs of these historical resources.

Methodology/Principal Findings

We sampled 27 Creole populations, 39 Iberian, 9 European and 6 Zebu breeds. We used microsatellite markers to assess the origins of Creole cattle, and to investigate the influence of different breeds on their genetic make-up. The major ancestral contributions are from breeds of southern Spain and Portugal, in agreement with the historical ports of departure of ships sailing towards the Western Hemisphere. This Iberian contribution to Creoles may also include some African influence, given the influential role that African cattle have had in the development of Iberian breeds, but the possibility of a direct influence on Creoles of African cattle imported to America can not be discarded. In addition to the Iberian influence, the admixture with other European breeds was minor. The Creoles from tropical areas, especially those from the Caribbean, show clear signs of admixture with Zebu.

Conclusions/Significance

Nearly five centuries since cattle were first brought to the Americas, Creoles still show a strong and predominant signature of their Iberian ancestors. Creole breeds differ widely from each other, both in genetic structure and influences from other breeds. Efforts are needed to avoid their extinction or further genetic erosion, which would compromise centuries of selective adaptation to a wide range of environmental conditions.  相似文献   

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