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排序方式: 共有214条查询结果,搜索用时 15 毫秒
1.
Genotyping,pedigree reconstruction and endocrinological characterization of Acipenser naccarii (Bonaparte, 1836) using microsatellite markers and plasma steroid levels 下载免费PDF全文
Ilaria Guarniero Laura Stancampiano Alessia Cariani Nadia Govoni Albamaria Parmeggiani Damiano Barboni Oliviero Mordenti 《Aquaculture Research》2017,48(11):5550-5560
This study aimed to set up a method for the long‐term management of Adriatic sturgeon, through the analysis of sex steroids and the genetic profiling of individuals in order to maximize the already reduced genetic variability of this species. Ten A. naccarii adults (nine of captive origin, one captured in the Ticino river and then moved into captivity) and eight subadults located in a semi‐natural land‐locked pond in Abbiategrasso (Milan, Italy) were analysed. Plasma testosterone differed significantly in the eight analysed subadults allowing their differentiation into two groups: the first group with an average testosterone concentration of 5.42 ± 1.31 ng/ml (probably female) and the second group with an average of 423.14 ± 75.97 ng/ml (probably male), as subsequently confirmed by artificial stripping. The plasma testosterone level was also significantly different between adult males and females (371.37 ± 43.58 vs. 95.34 ± 51.10 ng/ml), while the E2 levels showed no significant differences. Animals were genotyped on the basis of 10 microsatellite loci and their parental relationships were defined: four adults, two females and two males, generated the eight subadults. On the basis of pedigree analyses and genetic distances, 15 unrelated couples were identified for the future breeding seasons. Finally, the adult female captured in the Ticino River showed an interesting genetic profile, widely different from all of the other 17 specimens analysed, and represents a valuable source of genetic diversity. 相似文献
2.
Thirty-nine grapevine cultivars widely grown in Portugal, especially in Vinhos Verdes and Douro regions, and two well known international cultivars as standards, were genotyped at 12 microsatellite loci. The number of alleles per locus ranged from 6 to 12, and the number of allelic combinations per locus from 13 to 26. The total number of unique genotypes in the 12 analysed loci was 120, having most of the cultivars (38 out of 41) at least one unique genotype in any of the loci. The microsatellite profiles were adequate to discriminate 41 cultivars. The level of observed heterozygosity at each locus varied from 70.7% to 95.1%. VVMD28 has been revealed as one of the most informative markers. Several synonymies between Spanish and Portuguese cultivars were confirmed, and some homonymies are discussed. The genetic profiles of all 41 cultivars were searched for possible parent-offspring groups. The data obtained revealed the possible descendence of Touriga Franca from Touriga Nacional and Marufo. 相似文献
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中国荷斯坦种公牛BLAD遗传缺陷的分子检测及系谱分析 总被引:1,自引:0,他引:1
本试验运用限制性片段长度多态性聚合酶链式反应(RFLP-PCR)方法,检测我国荷斯坦种公牛白细胞粘附缺陷(bovine leukocyte adhesion deficiency,BLAD)基因的携带频率。共检测了来自全国14个公牛站的587头种公牛,发现BLAD携带者8头,携带率为1.36%。对现有公牛系谱信息分析显示,携带者公牛来自美国、加拿大和中国,其中6头携带者公牛可以追溯到共同祖先Osborndale Ivanhoe。此外,本研究还对我国荷斯坦牛遗传缺陷的控制和携带者公牛的利用提出建议。 相似文献
5.
D.?H.?Xu S.?Wahyuni Y.?Sato M.?Yamaguchi H.?Tsunematsu T.?BanEmail author 《Genetic Resources and Crop Evolution》2006,53(5):883-889
To evaluate the genetic diversity and to clarify the genetic relationships of Japanese peach cultivars, we analyzed the amplified
fragment length polymorphism (AFLP) and traced the pedigree of 17 Japanese commercial peach cultivars and six traditional
accessions. Sixteen AFLP primer combinations produced a total of 837 fragments and 146 polymorphic bands with a polymorphism
percentage of 17.5%. All of the peach accessions could be identified from differences in at least 10 polymorphic bands. A
cluster analysis showed that all the Japanese commercial peach cultivars, except ‘Kiyomi’ and ‘Jichigetsuto’, formed a major
group consisting of three sub-groups. Of the six traditional accessions, four were genetically distant from the Japanese commercial
peach cultivars while two accessions from China were classified into the Japanese commercial peach cultivars group. Both the
AFLP analysis and pedigree tracing suggested that Japanese commercial peach cultivars are mainly derived from ‘Shanhai Suimitsuto’,
one of the traditional accessions from China. Although the genetic relationships revealed by AFLP were generally in agreement
with those shown by the pedigree information, some contradictions were found. Combining the AFLP results and pedigree information
can provide a better understanding of the genetic relationships of Japanese peach cultivars. 相似文献
6.
Kevin Alan Glover Øystein Skaala Anne Grete Eide Søvik Tor Arne Helle 《Aquaculture Research》2011,42(9):1323-1331
Seven samples, each consisting of approximately 50 Atlantic salmon, were collected from five marine farms in Norway. These farms reported to rear fish originating from the same commercial breed; however, all samples followed a unique route of production from breeder to marine farm via egg, fry and smolt producers. A group of farmed escapees (n=50) were also captured. Following genotyping with 18 microsatellite loci, the global FST was 0.083, and pair‐wise values were as high as 0.158. Four clusters, with varying degrees of genetic differentiation, were identified among samples from the farms, and the source of the escapees was identified successfully. It is suggested that the genetic differences observed among samples from the farms were created through the process of genetic drift, facilitated by parallel sub‐strains, extensive within‐strain selection and low to moderate numbers of adults contributing to batches of eggs. In conclusion, this study has demonstrated that genetic identification of escaped Atlantic salmon, back to the farm of origin, may be possible even when farms rear fish reported to originate from a single breeder. 相似文献
7.
The establishment and evaluation of family lines using pedigree information provides an advanced understanding of the variability that exists for complex, economically valuable traits and is a necessary step in the execution of an effective breeding programme. The aim of this study was to assign parentage to mass‐spawned Haliotis midae juveniles using species‐specific microsatellite markers. Screening of wild abalone individuals revealed that the nine loci selected complied with the minimum requirements for parentage analyses: a null allele frequency <5% as well as a high number and frequency of alleles per locus. A total of 598 individuals were genotyped (198 breeding individuals and 400 F1 progeny) from two farms, with parentage results yielding 91% and 90% successful assignment for Farms A and B respectively. This study, therefore, provided the necessary pedigree information required for controlled breeding of individual adult abalone and indicated the usefulness of the panel of microsatellite markers selected for parentage assignment. 相似文献
8.
牛肉近红外光谱的地域及饲养期特征分析 总被引:1,自引:0,他引:1
【目的】探讨利用近红外光谱分析技术区分不同地域来源和饲养期牛肉的可行性,为牛肉产地溯源和产地确证等监管措施提供分析方法和理论依据。【方法】利用近红外光谱仪测定在内蒙古太仆寺旗、陕西杨凌区、河南南阳市实施的人为迁徙饲养模型试验中的18头肉牛肌肉样品的光谱,结合饲料和饲养方式,比较地域和饲养期样品之间的光谱特征差异,并利用主成分分析比较样品的空间分布。【结果】牛肉样品近红外光谱特征与地域、饲料种类和饲养方式等因子密切相关;同一地域不同饲养期和同一饲养期不同地域牛肉的近红外光谱特征均有显著差异;利用主成分分析能将不同地域来源和饲养期样品区分开。【结论】地域和饲养期对牛肉近红外光谱均有显著影响,进行牛肉产地溯源和产地确证时必须考虑地域和饲养期等因子;近红外光谱分析技术用于区分不同地域来源和饲养期的牛肉是可行的。 相似文献
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利用系谱分析探讨水稻广亲和性的遗传 总被引:8,自引:0,他引:8
就水稻恢复系T984及其7个系谱亲本C57、京引35、300号、 科情3号、IR26、IR24和IR8的亲和性进行了测定分析。结果表明受测的7个系谱亲本均不具有广亲和性,而T984却具有广亲和性,其与南京11、秋光和早沙粳测交F1的结实率分别为72.84%、74.42%和67.24%。从而证实了非广亲和性的籼粳亚种间杂种后代也可产生广亲和的品种. 相似文献