四川及重庆产五种姬鼠的阴茎形态学Ⅰ. 软体结构的分类学意义探讨

对四川及生态产５种习雄性个体的阴茎形态进行了比较研究,结果发现５种姬鼠雄性个体阴茎头的软体结构在不同种间,不同亚种间,其至同一种和同一亚种由于产地不同都有其牧民性及稳定性,在某些地域还存在不同型的同域分显示：１）黑线姬鼠长江亚种和华北亚种应合为长江亚种。高山姬鼠作为独立种的地位值得不怀疑;２）四川产姬鼠齿动物可能存在亲上;３）新亚种和新种形成的可能途径之一是由于交配器变化而导致生殖隔离。     

长尾姬鼠分类地位的探讨

长期以来长尾姬鼠（Ａｐｏｄｅｍｕｓ ｏｒｅｓｔｅｓ）的分类地位一直不确定。基于在云南中部无量山区采集的大量姬鼠类标本,经单变量和多变量分析,长尾姬鼠明显区别于中华姬鼠（Ａ．ｄｒａｃｏ）。主要鉴别特征在于体长、尾长及尾长与本长的比例,且相关分析表明,该两种的尾长与体长具显著的相关性。而对无量山姬鼠的生态地理分布研究显示,长尾姬鼠与中华姬鼠具完全同域分布,因此认为长尾姬鼠是一有效种。无量山区现有姬鼠３     

Serosurveillance of Scrub Typhus in Small Mammals Collected from Military Training Sites near the DMZ, Northern Gyeonggi-do, Korea, and Analysis of the Relative Abundance of Chiggers from Mammals Examined

Comprehensive quarterly serosurveillance on scrub typhus in small mammals collected from military training sites located near the Demilitarized Zone (DMZ), northern Gyeonggi-do (Province), ROK was conducted to determine the potential rodent-borne and associated ectoparasite disease risks to military personnel. A total of 1,196 rodents and insectivores representing 8 species, Apodemus agrarius (87.3%, n = 1,044), Mus musculus (5.4%, n = 65), Crocidura lasiura (3.3%, n = 40), Microtus fortis (2.6%, n = 31), Micromys minutus (0.3%, n = 4), Tscherskia triton (0.3%, n = 4), Rattus norvegicus (0.3%, n = 4), and Myodes regulus (0.3%, n = 4) were assayed for the presence of antibodies to Orientia tsutsugamushi. O. tsutsugamushi antibodies were detected in 6 of 8 species and seroprevalence determined; A. agrarius (45.6%), M. musculus (23.1%), M. fortis (48.4%), M. minutus (50.0%), T. triton (50.0%), and R. norvegicus (25.0%). A total of 31,184 chigger mites collected from 508 rodents and insectivores were slide-mounted and 10 species belonging to 4 genera were identified. Leptotrombidium pallidum (53.4%) was the most frequently collected, followed by L. palpale (15.7%), Neotrombicula tamiyai (14.3%), L. orientale (10.7%), L. zetum (3.1%), Walchia fragilis (2.1%), and L. gemiticulum (0.8%), while the remaining 3 species, L. subintermedium, N. gardellai, and Euschoengastia koreaensis were rarely observed (prevalence < 10%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4), L. orientale (45.0), and L. palpale (21.4), were observed during the spring season.     

洞庭湖区两种小型兽类的游泳 行为及皮毛防水性比较

洞庭湖区水量丰富且季节变化大,对湖区小型哺乳动物造成一定压力。具有游泳能力的小型哺乳动物可利用水体逃生扩散,游泳能力影响其分布情况。黑线姬鼠（Apodemus agrarius）为洞庭湖区主要优势鼠种,在湖区各生境中均占优势;灰麝鼩（Crocidura attenuata）在湖区亦有分布,二者分布特点不同,可能与游泳能力有关。为观察比较二者游泳能力,野外捕捉动物进行游泳实验,观察并比较二者的游泳行为及皮毛吸水率。结果发现,灰麝鼩采用狗刨式在水面游泳,背腹部没入水中,身体与水面倾斜度较大,利用四肢划水提供动力,游泳期间无漂浮行为,皮毛吸水率随游泳时间延长而增长,游泳行为及皮毛吸水率无性别差异。黑线姬鼠也采用狗刨式在水面游泳,仅腹部没入水中,身体与水面倾斜度较小,主要利用后肢划水,可漂浮在水面,皮毛吸水率随游泳时间延长而增长,游泳行为及皮毛吸水率无性别差异。两者比较显示,黑线姬鼠采用水生适应程度较好的游泳方式,游泳能力比灰麝鼩强,其皮毛防水性能优于灰麝鼩,皮毛吸水率和吸水率速率显著低于灰麝鼩。上述结果表明,黑线姬鼠和灰麝鼩都具有一定的水中运动能力,但黑线姬鼠的游泳方式及皮毛防水性比灰麝鼩强,可能是其广泛分布于洞庭湖湖区的原因之一。     

A spatial aspect on mitochondrial DNA genealogy in Apodemus peninsulae from East Asia

Apodemus peninsulae is a field mouse that inhabits the broad-leafed forests of temperate Eurasia. We examined the mitochondrial cytochrome b gene in 57 individuals of A. peninsulae from northeastern Asia, including Siberia, Primorye, Magadan region, Sakhalin, Hokkaido, and the Korean Peninsula. The genealogy of the mitochondrial DNA (mtDNA) in A. peninsulae was shown to have substantial geographic affinity, suggesting geographic architecture of northeastern Asia, including the islands of Sakhalin and Hokkaido, played important roles on the cladogenesis. Taking into account the presence of region-specific anciently divergent mtDNA types, three parts of the regions of Primorye, Siberia, and the Korean Peninsula can be denoted as refugia for A. peninsulae during the substantial period of the Quaternary glacial ages. Among the geographic regions examined, Primorye is likely to be the most influential one, from which the mtDNA is thought to have migrated to the neighboring regions of Sakhalin, Hokkaido, the Magadan region, and Siberia during the evolution of this species.     

Mitochondrial phylogeography of the Woodmouse (Apodemus sylvaticus) in the Western Palearctic region

We sequenced 965 base pairs of the mitochondrial DNA cytochrome b from 102 woodmice (Apodemus sylvaticus) collected from 40 European localities. The aims of the study were to answer the following questions. (i) Did the Mediterranean peninsulas play a role as refuge for woodmice? (ii) Is genetic variability of A. sylvaticus higher in the Mediterranean region compared with northern Europe? (iii) Are the patterns of the postglacial colonization of Europe by woodmice similar to those presently recognized for other European species? The results provide a clear picture of the impact of the Quaternary glaciations on the genetic and geographical structure of the woodmouse. Our analyses indicate a higher genetic variability of woodmice in the Mediterranean peninsulas compared to northern Europe, suggesting a role of the former as refuge regions for this small mammal. An original pattern of postglacial colonization is proposed where the Iberian and southern France refuge populations colonized almost all European regions. The Sicilian population appears to be very differentiated and highly variable. This emphasizes the importance of this island as a ‘hot spot’ for the intraspecific genetic diversity of the woodmouse. Finally, woodmice in North Africa originated from southwestern Europe, most probably as a result of a recent anthropogenic introduction.     

Population structure of the large Japanese field mouse, Apodemus speciosus (Rodentia: Muridae), in suburban landscape, based on mitochondrial D-loop sequences

Genetic structure of the large Japanese field mouse populations in suburban landscape of West Tokyo, Japan was determined using mitochondrial DNA control region sequence. Samples were collected from six habitats linked by forests and green tract along the Tama River, and from two forests segregated by urban areas from those continuous habitats. Thirty-five haplotypes were detected in 221 animals. Four to eight haplotypes were found within each local population belonging to the continuous landscape. Some haplotypes were shared by two or three adjacent local populations. On the other hand, two isolated habitats were occupied by one or two indigenous haplotypes. Significant genetic differentiation between all pairs of local populations, except for one pair in the continuous habitats, was found by analysis of molecular variance (amova). The geographical distance between habitats did not explain the large variance of pairwise F(ST)-values among local populations. F(ST)-values between local populations segregated by urban areas were higher than those between local populations in the continuous habitat, regardless of geographical distance. The results of this study demonstrated quantitatively that urban areas inhibit the migration of Apodemus speciosus, whereas a linear green tract along a river functions as a corridor. Moreover, it preserves the metapopulation structure of A. speciosus as well as the corridors in suburban landscape.     

Phylogeographic history of the yellow-necked fieldmouse (Apodemus flavicollis) in Europe and in the Near and Middle East

The exact location of glacial refugia and the patterns of postglacial range expansion of European mammals are not yet completely elucidated. Therefore, further detailed studies covering a large part of the Western Palearctic region are still needed. In this order, we sequenced 972 bp of the mitochondrial DNA cytochrome b (mtDNA cyt b) from 124 yellow-necked fieldmice (Apodemus flavicollis) collected from 53 European localities. The aims of the study were to answer the following questions: Did the Mediterranean peninsulas act as the main refuge for yellow-necked fieldmouse or did the species also survive in more easterly refugia (the Caucasus or the southern Ural) and in Central Europe? What is the role of Turkey and Near East regions as Quaternary glacial refuges for this species and as a source for postglacial recolonisers of the Western Palearctic region? The results provide a clear picture of the impact of the quaternary glaciations on the genetic and geographic structure of the fieldmouse. This species survived the ice ages in two main refuges, the first one in the Italo-Balkan region; the second one in Turkey and the Near East regions. It is from the Balkan refuge that it recolonised all European regions at the end of the last glaciation. The Turkish and Near East populations are distinct from the European ones and they did not recolonise the Palearctic region probably because: (i) they were blocked by the Black Sea and the Caucasus, (ii) the long term presence of fieldmice populations in the Balkans prevented their expansion. These are genetically differentiated from the European and Russian ones and could be described as a particular subspecies. This result emphasises the importance of Turkey and the Near and Middle East regions as a refuge for Palearctic mammals.     

Apodemus agrarius as a new definitive host for Neodiplostomum seoulense

A total of 1,496 rodents and insectivores were live-trapped at Yeoncheon-gun (n = 351), Paju-shi (804), and Pocheon-gun (343), Gyeonggi-do (Province), and examined for intestinal helminths, including Neodiplostomum seoulense, seasonally from December 2004 to September 2005. Six species of rodents, including Apodemus agrarius (1,366), Mus musculus (32), Micronytus fortis (28), Eothenomys regulus (9), Micronys minutus (6), and Cricetulus triton (3), and 1 species of insectivores Crocidura lasiura (54) were collected. A total of 321 adult N. seoulense were collected from 19 (1.4%) A. agrarius. The worm burden ranged from 1 to 101 per A. agrarius (mean; 16.9). No N. seoulense was observed in other rodent or insectivore species examined. The infection rate during autumn (4.5%) was higher than those during spring (0.8%), summer (0.8%), and winter (0.5%). The average number of N. seoulense in infected A. agrarius was the highest in spring (66.0 specimens), followed by autumn (15.2), winter (4.5), and summer (3.3). This study first confirms that A. agrarius is a natural definitive host for N. seoulense, and demonstrates that the infection rates and intensities vary seasonally and geographically.     

高山姬鼠种群数量动态及预测预报模型

为了摸清高山姬鼠种群数量变节变动规律,探讨其种群数量预测方法,采用夹夜法调查逐月捕获率,用捕获率为预测指标,建立种群数量预测预报模型。对1996-2008年贵州省大方县高山姬鼠种群数量动态及种群数量进行分析预测,结果表明:高山姬鼠主要分布于稻田、旱地耕作区,是大方县农田害鼠优势种,占总鼠数的62.32%。10a平均捕获率为(2.58±1.27)%,全年种群数量变动曲线呈单峰型,各年度种群数量的变化曲线基本相似,一年内种群数量在6月份出现1个数量高峰,平均捕获率达(4.63±3.03)%。不同年度、不同月份、不同季节之间种群数量存在显著差异。根据历年高山姬鼠种群数量变动幅度及发生危害情况,结合当地鼠害防治指标,制定了高山姬鼠种群数量分级标准。分析1996-2008年高山姬鼠数量高峰期前各月捕获率、种群繁殖参数(性比、怀孕率、胎仔数、睾丸下降率、繁殖指数)与数量高峰期6月种群密度的关系后发现,4月份种群数量基数与6月份种群密度之间相关极显著,运用回归分析方法,建立了应用4月份种群数量基数(X)预测数量高峰期6月份种群密度(Y)的短期预测预报模型:Y=1.7558X+0.1442,可提前2个月预测当年数量峰种群密度和发生程度,经回测验证,数值和数量级预测值与实测值基本相符,数值预测和数量级预测平均吻合率为92.84%、100.00%,结果比较准确,故该预测预报模型具有一定的实用性和可行性。