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11.
Human and livestock diseases can be difficult to control where infection persists in wildlife populations. Control of bovine tuberculosis (bTB) in British cattle is complicated by the maintenance of Mycobacterium bovis (the causative agent of bTB) in badgers, acting as reservoirs of infection. Although over 20 000 badgers were culled to control bTB between 1975 and 1997, the incidence of bTB in cattle has substantially increased in parts of Great Britain in recent decades. Our case-control study, involving 1208 cattle herds, provides further evidence of the detrimental effect of localized reactive badger culling in response to the disclosure of a confirmed bTB herd breakdown in cattle. The presence of any reactive badger culling activity and increased numbers of badgers culled in the vicinity of a herd were associated with significantly increased bTB risk, even after adjusting for other important local risk factors. Such findings may partly explain why some earlier localized approaches to bTB control were ineffective. 相似文献
12.
13.
The South American leafhopper genus Parandanus Linnavuori & DeLong (Deltocephalinae: Deltocephalini) is reviewed and four of its six species are illustrated and male genital characters are provided. Three new species from Peru, Parandanus
longistylus Duan, sp. n., Parandanus
nigricephalus Duan, sp. n. and Parandanus
paracruciatus Duan, sp. n. are described. A key to species is also provided. 相似文献
14.
The planthopper genus Neodurium Fennah is reviewed and Neodurium
fennahi Chang & Chen, sp. n. (Hemiptera: Fulgoromorpha: Issidae) from China (Yunnan), is described and illustrated. A checklist of the species of Neodurium is given and a key provided for their separation. The female genitalia of Neodurium species are described for the first time. 相似文献
15.
16.
Christophe Sola Ingrid Filliol Eric Legrand Igor Mokrousov Nalin Rastogi 《Journal of molecular evolution》2001,53(6):680-689
This paper deals with phylogenetic relationships among a set of 90 clinical strains representative of the worldwide diversity
of the Mycobacterium tuberculosis complex (Kremer et al. 1999) using eight independent genetic markers: IS6110, IS1081, the direct repeat (DR) locus, and five variable number of tandem DNA repeat loci (VNTR). In a preliminary experiment, phylogenetic
trees based on single markers were constructed that led to the detection of some similarities between the VNTR-based and the
spoligotyping-based phylogenetic trees. In the second step, a more global phenetic approach based on pairwise comparison of
strains within each typing system was used, followed by calculations of mean genetic distances based on all the eight loci
and the use of the neighbor-joining algorithm for tree reconstruction. This analysis confirmed our preliminary observations
and suggested the existence of at least two new phylogeographical clades of M. tuberculosis, one defined as the ``East African–Indian family' (EA-I), which may find its origin on the African or Asian continents, and
the other as the ``Latin American and Mediterranean' (LA-M) family. The existence of these two families was also validated
by an independent phylogenetic analysis of spoligotyping on a larger set of shared types (n= 252) and further corroborated by VNTR and katG–gyrA results. The potential origin of these families of bacilli is discussed based on cattle domestication and human migration
history. In conclusion, the information contained in insertion sequence and repetitive DNAs may serve as a model for the phylogenetic
reconstruction of the M. tuberculosis complex. 相似文献
17.
A new scleractinian coral species, Cyphastrea
kausti
sp. n., is described from 13 specimens from the Red Sea. It is characterised by the presence of eight primary septa, unlike the other species of the genus, which have six, ten or 12 primary septa. The new species has morphological affinities with Cyphastrea
microphthalma, from which it can be distinguished by the lower number of septa (on average eight instead of ten), and smaller calices and corallites. This species was observed in the northern and central Red Sea and appears to be absent from the southern Red Sea. 相似文献
18.
19.
PCR法快速检测临床标本中结核杆菌DNA 总被引:2,自引:0,他引:2
应用聚合酶链反应(PCR)快速检测临床标本(脑脊液、胸水、腹水、血、痰液)中的结核杆菌DNA,特异性扩增片段123bp,为结核杆菌的特异性重复序列IS6110部分基因。PCR检测人型结核杆菌的敏感性达10fgDNA。临床标本的PCR检测阳性率(23.3%)明显高于抗酸染色涂片(2.9%)和细菌培养(5.7%)的阳性率(P〈0.05)。通过设立对照系统及对扩增产物酶切分析,表明该法无假阴性结果(特异 相似文献
20.
João Queiros Joaquín Vicente Mariana Boadella Christian Gortázar Paulo Célio Alves 《Biological journal of the Linnean Society. Linnean Society of London》2014,111(1):209-223
The influences of management practices and past demographic history on genetic diversity are of critical relevance to sustainable practices and the conservation of wildlife populations. The red deer (Cervus elaphus) is an interesting model species to address these questions because it has a wide geographical distribution and it has been intensively managed for humans in the last decades. In the present study, we have analyzed the impact of recent management practices on the genetic diversity of Iberian red deer populations and assessed the genetic variation effects on population and individual fitness‐related traits. Four populations subjected to distinct management systems were selected: Cabañeros (CB) and Doñana (DN), not hunted populations; Fraga/Caspe (FG/CP), open hunting area with very low or absent management; and PE, fenced private hunting estate founded 31 years ago through the introduction of deer of different origins. Ten microsatellites were amplified in a total of 172 individuals. Additionally, several fitness‐related traits such as the presence of tuberculosis compatible lesions (TBCL), spleen weight (SW), and body length (BL) were estimated. We found a marked genetic variation and differentiation among populations, suggesting a strong population structure. In the fenced population, the introduction of genetically distinct animals has led to high genetic variability (no evidence of inbreeding) despite intensive management. Lower levels of genetic diversity were observed in two historically isolated natural populations (DN and FG/CP). The past demographic history of Iberian populations appears to be more relevant than the current management policy in shaping the genetic variability of natural populations. Population genetic diversity may correlate with life‐history traits and disease susceptibility, which could compromise the conservation and management of these wildlife populations. Although no significant effects of individual genetic diversity (general and local effect hypotheses) were observed on TBCL, SW and BL, some single‐locus effects had almost significant trends for the TBCL and SW traits. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 209–223. 相似文献