云南省剑川县鼠疫自然疫源地宿主媒介情况分析

了解鼠疫自然疫源地的宿主、媒介群落结构及其种群动态,为提出针对性的鼠疫防控策略与机制提供依据。云南省剑川县属于齐氏姬鼠和大绒鼠鼠疫自然疫源地的核心区,该区域小型兽类种类丰富,存在2种类型鼠疫菌,为进一步研究疫源地的演变提供了重要的现场模型。本文对剑川县1976-2019年鼠疫监测资料进行整理和分析,发现该疫源地室内共捕获小型兽类4目7科16属25种,绝对优势鼠种为褐家鼠,其他优势鼠种为黄胸鼠和小家鼠;室外捕获小型兽类5目8科21属31种,其中优势鼠种为齐氏姬鼠和大绒鼠。室内鼠密度在2005年以前基本在3.75%左右波动,2006年开始显著下降维持在0.49%左右波动;室外鼠密度常年在9.13%左右这一较高水平波动。该疫源地鼠体主要优势蚤种为方叶栉眼蚤、特新蚤和棕形额蚤,其中方叶栉眼蚤处于绝对优势地位。共检出细菌学阳性样本72份,检出F1抗体阳性样本95份。该疫源地存在时间长,宿主动物及媒介种类多差异大,但总体结构稳定。由于存在着鼠疫菌长期保存的自然和地理条件,有待于进一步的研究探讨其种群动态、疫情发生与自然条件等的关系模型。     

云南居民区鼠类体外寄生蚤物种多样性调查

【目的】了解云南居民区鼠类寄生蚤的群落结构和空间分布特征。【方法】根据云南不同经纬度、 海拔等自然环境条件, 于2007年4月-2012年11月, 选取云南17个县(市) 居民区作为样区, 系统开展鼠类体外寄生蚤的调查, 运用群落结构指标对居民区鼠类寄生蚤的群落特征和沿环境梯度的空间分布进行研究。【结果】结果显示： 在调查的17个县(市)室内共检获鼠类体外寄生蚤521头, 隶属4科7亚科9属12种。居民区寄生蚤的纬度和垂直分布类似, 低纬度和低海拔范围的种类相对较少, 印鼠客蚤和缓慢细蚤是室内寄生蚤的优势种。相对纬度和海拔较高的区域, 居民区寄生蚤种类增多, 但优势种不突出; 在经度水平分布上, 蚤种类于99°~101°E经度带形成一个高峰, 室内寄生的优势种印鼠客蚤和缓慢细蚤几乎在所有经度带都可见到分布, 显示了较宽的生态幅。另外, 居民区寄生蚤物种丰富度和多样性指数水平分布（纬度）和垂直分布呈现为单峰格局, 总体显示随着纬度和海拔的升高, 先升高后降低的分布特征, 而在另一个水平分布（经度）, 则呈现由西向东呈递减的趋势。【结论】研究认为, 云南居民区蚤类的空间分布表现为独特的地理区域特征, 气候环境、 森林植被和人类生活生产方式通过影响蚤类栖息生境来影响蚤类的分布。     

中国云南部分人间鼠疫流行区蚤类区系调查(英文)

归纳了中国云南 13个人间鼠疫流行区的调查资料 ,对调查疫区的蚤类区系进行了研究。总计捕获12 0 77只小兽 ,隶属啮齿目、食虫目及攀目 3个目中的 9科、2 9属、4 7种。从小兽体表共采获 9369只蚤 ,经分类鉴定 ,隶属 5科、18属、33种。 33种蚤及 4 7种小兽宿主均按其分类阶元详细列于文末。结果表明 ,山区蚤及小兽宿主的种数明显多于坝区。坝区农耕地的优势种相对简单 ,优势种地位突出 ,黄胸鼠及印鼠客蚤分别是最重要的宿主及蚤种 (构成比分别为 83 2 7%和 75 32 % )。山区的优势种相对较复杂 ,优势种的种类较多 ,但其构成比较低 ( 10 96%～ 4 7 95% )。黄胸鼠及绒鼠为山区地带的两种优势宿主 ,缓慢细蚤、端凹栉眼蚤、印鼠客蚤、偏远古蚤及短突栉眼蚤为山区地带的 5种优势蚤种。多数蚤种可寄生两种以上的小兽宿主 ,但其所寄生的主要宿主并不多。结果提示 ,作为疫区主要媒介的印鼠客蚤及其所对应的主要寄生宿主 (黄胸鼠 )在坝区突出的优势种地位 ,似可解释近年疫区的鼠疫病人主要出现在坝区的原因     

四川鼠疫疫源地青海田鼠巢蚤群落结构及其动态

目的掌握四川鼠疫疫源地青海田鼠巢蚤群落结构及其动态,为防止鼠疫传播提供理论指导。方法于2011年和2012年的5~9月在四川鼠疫疫源地逐月采集青海田鼠巢蚤,对其鉴定并统计分析,对鼠巢的染蚤率、蚤指数、巢蚤群落结构及优势种的季节变化进行了研究。结果两年共挖取87个有效巢,分离得到3715匹跳蚤,包括8个物种,其中细钩盖蚤和直缘双蚤指名亚种为优势种。巢染蚤率为100%。巢蚤指数、优势蚤种指数的月间差异显著(P0.05)。2011年巢蚤指数、优势蚤种指数均显著大于2012年(P0.05)。群落多样性指数和优势度指数没有显著的年间和月间差异(P0.05);2011年巢蚤群落均匀度指数显著小于2012年(t=-3.796,P0.05);巢蚤群落均匀度指数的月间差异显著(ANOVA:F=2.692,P0.05),其中,2011年9月为调查期间最低值(0.712)。结论四川鼠疫疫源地青海田鼠巢染蚤率高、巢蚤指数大,其中直缘双蚤指名亚种和细钩盖蚤为优势种。2012年巢蚤指数、优势种蚤指数均较2011年显著下降。巢蚤群落均匀度指数和物种数的变化存在显著的年间和月间差异。     

准噶尔盆地荒漠景观不同地貌类型鼠、蚤多样性及分布特征

为揭示鼠、蚤空间分布特征与变化规律,本研究以准噶尔盆地鼠疫自然疫源地为靶区,基于鼠类和蚤类的样点采集数据,计算不同地貌的鼠、蚤生态学指标并分析其相关性。基于不同行政区生态学指标计算结果,借助Moran′s I指数、重心模型、标准差椭圆等分析方法探究不同行政区鼠、蚤生态学指标的聚类特征,开展鼠、蚤的空间分布特征及变化规律的相关研究。结果表明：(1)通过对不同地貌鼠、蚤生态指标的研究,可得出鼠、蚤的物种多样性和生态优势度呈负相关,表明在物种多样性较高的群落中,鼠、蚤生态优势度表现不明显。鼠类物种多样性较高的地貌类型与蚤类物种多样性呈正相关,证实鼠类(宿主)物种数量增加,蚤类(寄生)物种的数量也在增加。低海拔地区鼠、蚤群落的相似性总体上大于中海拔地区群落相似性,且相似性系数q值与Cody指数呈相反变化趋势;(2)不同鼠、蚤指标单变量Moran′s I指数表明,鼠类数量、子午沙鼠数量、蚤类均匀度的全局Moran′s I指数大于0,且P值小于0.05,表现出空间集聚现象。单变量局部空间自相关分析结果表明,部分鼠、蚤指标存在多种聚类模式,其中最为典型的聚类模式是高—高聚类模式。不同鼠、蚤指标双变量...     

长爪沙鼠体蚤和巢蚤数量研究

1982～1996年对内蒙古自治区鄂托克前旗长爪沙鼠Meriones unguiculatus体蚤和巢蚤的数量进行了调查和分析,得到如下结果。获体蚤15种,同型客蚤指名亚种Xenopsylla conformis conformls (50.8%) 和秃病蚤蒙冀亚种Nosopsyllus laveiceps kuzenkovi (40.6%)为优势种。获巢蚤15种,秃病蚤蒙冀亚种(74.3%)为优势种;盔状新蚤Neopsylla galea (11.9%)和叶状切唇蚤突高亚种Coptopsyllus lamelliferardua (8.1%)为常见种。年巢蚤指数的均值是年体蚤指数的6.92倍。体蚤指数与巢蚤指数不相关(P>0,05),体染蚤率与巢染蚤率不相关(P>0.05)。不同年份 的体蚤和巢蚤多样性比较稳定。连续两年春季或秋季秃病蚤巢蚤指数大于10只后,可能流行动物鼠疫。     

宁夏银北盐碱地油葵田土壤动物多样性及群落结构

【目的】调查宁夏银北盐碱地油葵田的土壤动物多样性及群落结构,探讨不同改良时间盐碱地土壤动物多样性及群落结构与环境因子之间的相关性。【方法】生物与环境因子之间的关系研究一直是生态学研究的热点,尤其是恢复生态学中如何设计环境因子来恢复生物群落的结构和功能最近引起了国内外学者的关注。以宁夏银北盐碱地油葵田为对象,研究了不同改良时间盐碱地中油葵田土壤动物与环境因子的相互关系,采用野外调查和室内试验相结合。【结果】共采集12个土壤动物类群,优势类群为弹尾目(60.67%)、蜱螨亚纲(23.24%)和鞘翅目(6.45%);土壤动物物种多样性、丰富度指数和均匀度在未改良盐碱地中较高。【结论】土壤pH值、碱化度和全盐质量分数是土壤动物分布的限制因素,土壤动物的数量随土壤pH值、碱化度和全盐质量分数的降低而增加。这些结果为盐碱地改良的恢复与评价提供了重要的数据支持和基础资料。     

雷州半岛臭NFDA6的一些生物学特性

臭NFDA7是一种小型哺乳类动物,与黄胸鼠、褐家鼠、小家鼠组成南方家栖鼠形哺乳类动物群体.根据雷州半岛40多年(1950～1994年)鼠疫监测和10年(1985年2月～1995年1月)鼠情监测资料,对臭NFDA7的数量、分布、繁殖等方面进行了分析研究.结果,臭NFDA7占家栖鼠形哺乳类动物群体比例逐年上升,80年代达高峰;其分布是农村多于城市,野外也有发现;月份分布呈马鞍形曲线;全年均可繁殖,月均怀孕率为35.7%,每胎胎仔数1～7只,平均为3.15只,频率分布近似正态.     

滇西北高原藏区小型兽类体表寄生蚤的生态位特征

为探讨云南西北高原藏区小型兽类体表寄生蚤的生态位特征,根据海拔和地形等自然环境特点,在德钦县选取42个调查样点,划分为5个垂直带,4种生境,采用铗夜法和笼日法捕获小兽,梳捡其体表寄生蚤,运用生态位宽度指数（B_i）和生态位重叠指数（NO）对其生态位特征进行分析。结果：共梳捡寄生蚤1275头,隶属4科9亚科17属33种,其中迪庆额蚤和云南栉眼蚤为优势种,常见种12种,稀有种19种。在海拔资源轴上,B_i值前三分别是特新蚤德钦亚种0.698、棕形额蚤0.690、斯氏新蚤川滇亚种0.667;生境资源轴上,B_i值前三分别是：无值大锥蚤0.630、特新蚤指名亚种0.57、特新蚤德钦亚种0.537;寄主资源轴上,B_i值前三为绒鼠怪蚤0.584、迪庆额蚤0.567、棕形额蚤0.553;多维生态位宽度来看,特新蚤德钦亚种和迪庆额蚤B_i值较大,分别为1.031、1.019。海拔、生境、寄主生态位重叠指数中,有意义的重叠种对分别占比35.6%、39.39%、9.28%;完全不重叠的种对分别占比26.89%、18.56%、51.14%;完全重叠的种对分别占比2.27%、13.26%和0.19%。三种生态因子中,优势种和常见种的生态位宽度值较大,对资源的利用能力和竞争能力较强。不同生态因子的生态位重叠指数格局不同,与资源轴本身有关。有意义的重叠和完全不重叠的种对占比较多,前者多为优势种、常见种、稀有种两两之间重叠,重叠指数越高,竞争关系越激烈;完全不重叠的种对多为稀有种之间,无资源利用竞争关系。总体来说,德钦县小兽体表寄生蚤种类丰富,生态位分化较为均匀,本研究可为该地蚤传疾病的监测防控提供生态学依据。     

影响专食性广聚萤叶甲产卵选择的因素

【背景】广聚萤叶甲幼虫常群聚于部分豚草植株取食,可能与成虫产卵选择有关,因此,探究广聚萤叶甲产卵选择的影响因素具有重要意义。【方法】于2005年在广聚萤叶甲的主要分布区（江苏、江西、湖北、湖南）进行了1次随机抽样调查,并在南京城郊于2008年5月25日～9月1日进行了豚草的定点定期跟踪调查,用广义线性模型分析调查因子的影响。【结果】随机抽样调查结果表明,卵块数量随豚草植株冠层直径和健康程度的增大而显著增多,冠层直径每增大1cm,卵块数增多2%;健康程度每提高1级,卵块数增加近2.1倍;在豚草植株被利用程度增大的情况下,卵块数量随植株健康程度增大而增多,如果植株上增加1头幼虫或蛹,则植株健康程度每提高1级,卵块数增多2%,但植株冠层每增大1cm,卵块数减少0.6%。定点定期调查结果表明,豚草上的着卵块概率受豚草斑块大小、植株冠层直径、发育期和生境光照情况等因素的显著影响,豚草斑块每增加1株植物,产卵概率提高0.5%;植株冠层直径每增大1cm,产卵概率提高3%;在暴露生境中的豚草上产卵的概率比遮阴（树下）下的豚草提高近1倍。【结论与意义】豚草植株个体特性对着卵数量有显著影响,而豚草个体和群体特性以及小生境显著影响产卵发生。     

蚤消化系统的研究：14种蚤前胃的结构

蚤的前胃结构与其传病机制密切相关。 本文应用解剖、组织切片和扫描电镜研究14种蚤的前胃。前胃的外部形态可分为：球状、椭球状、管状和圆台状。前胃刺内部有原生质。 前胃刺的末端形态可分为：钩形、弯叉形、叶形、针形、矛形、喇叭口形、“W”形、大叉形、小叉形、马刀形、锥形和舌形。 前胃刺包括有齿刺和无齿刺两类,有齿刺上齿的分布茫固有：1/2、1/3、1/4、2/3和刺全长。未观察到花蠕形蚤 yermipsylla alakurt 和缓慢细蚤Leptopsylla sehnis的前胃刺上有齿。 前胃刺末端形态和齿的分布呈现出科的相似性。 前胃刺基部的形态有：四棱形、正方形、五边形、不规则五边形、六边形、卵形和圆形。致痒蚤Pulex irrirans和印鼠客蚤Xenopsylla cheopis的前胃刺较粗长、骨化强、在刺两侧具较密的齿且多分布于刺的一半以上,这些特征可能适宜于鼠疫杆菌的生存与大量聚集。没有观察到俊潜蚤Tunga callida的前胃和前胃刺。     

Parasite-host relationship of flies and small mammals in the Omsk region

A generalized analysis of data on a flea fauna, range of their hosts in various natural zones, and features of parasite-host relationships between fleas and small mammals obtained in the Omsk province during long term researches in 1963-1997 is given. 35 flea species are recorded. The most mass species both on animals and in their nest is Ctenophthalmus assimilis; the numerous species are Amalareus penicilliger, Megabothros rectangulatus, M. walkeri, Peromyscopsylla silvatica, Ctenophthalmus unciatus, Palaropsylla sorecis, Doratopsilla birulai, Neopsylla pleskei, Hystrichopsylla talpae; the usual species--Ceratopsyllus garei, M. calcarifer, M. turbidus, Frontopsylla elata, Amphipsylla sibirica, A. kuznetzowi, Peromyscopsylla dasycnema, Radinopsylla integella, Catalagia dacenkoi. Other species are less numerous or infrequent. The general infection rate of the flea populations on rodents and insectivores makes 30.4%. For certain species it reaches 65.1% (on red-backed vole Cletrionomys rutilus), for regular groups--86.9% (on shrews of the genus Sorex). The greatest variety of the flea populations is observed on Microtus arvalis, the least one--on Sorex caecutiens and S. daphaenodon. In the nests of small mammals the variety of fleas is significantly lower. Based on the index of flea species relative "loyalty" to small mammals and their nest we have recognized 6 groups of fleas.     

Benefits, Costs and Constraints of Anti-Parasitic Grooming in Adult and Juvenile Rodents

Grooming behaviour plays various roles in the health care, reproduction, and social life of an individual vertebrate. However, the reasons for the variability in time spent grooming amongst species, populations and individuals are not fully understood. We tested the hypothesis that the main role of grooming is ectoparasite removal and thus that time spent grooming by an animal reflects the costs of parasite infestation offset against the costs of grooming. The test was conducted on a rodent, Meriones crassus, that is parasitised by a flea, Xenopsylla conformis. We monitored behaviour of juvenile and adult rodents before and after flea infestation and quantified the probability of mortality of fleas with respect to the time spent grooming in adults compared with juvenile rodents. We predicted that: (1) increased costs of flea infestation (e.g. in parasitised as opposed to flea‐free rodents and in juveniles as opposed to adults) increases time spent grooming and (2) mortality probability per flea increases with increasing time spent grooming and is higher for fleas on juveniles than for fleas on adult rodents. We were interested to discover at the expense of which activity grooming is increased. Our findings established that the major role of grooming is in flea removal, as exposure to fleas evoked grooming activity in all rodents and grooming activity explained 57–70% of the variation in flea mortality. Furthermore, we showed that the rise in grooming activity was at the expense of resting. However, we found only partial support for the predicted increase in grooming time with increasing costs of flea infestation. Flea infestation did indeed increase the time spent grooming by rodents. Nevertheless, juvenile rodents who incur higher costs of flea infestation spent less time grooming than adults and sustained similar flea densities, suggesting that these hosts are constrained by some other factors, such as feeding time.     

Seasonal patterns of rodents, fleas and plague status in the Western Usambara Mountains, Tanzania

Field and commensal rodents were live-trapped at three villages in an active focus of plague (Yersinia pseudotuberculosis pestis) in Lushoto District, Western Usambara Mountains, Tanga Region, Tanzania, from December 1983 to November 1984. Their flea ectoparasites were collected, identified and counted. The rodent carcasses were serologically examined for specific plague antibodies and antigens, and bacteriologically examined for bipolar staining bacilli. A total of 1758 traps were set during the 12-month period and 924 animals were caught. From these, 1037 fleas were collected. Rattus rattus (L.), Praomys natalensis (Smith) and Lophuromys flavopunctatus Thomas comprised the largest proportions of the rodent population, while Dinopsyllus lypusus Jordan & Rothschild, Ctenophthalmus calceatus Waterston and Xenopsylla brasiliensis (Baker) were the dominant flea species. Rodents were most abundantly trapped during December and January. Flea indices were highest from December to May. Human plague was most active from November to March. Rodents contained plague antibodies every month except May and July, with a peak in September. Plague antigens and bipolar bacilli were detected in rodent organs during January-April. From the product of abundance and infection rate, the most prevalent rodent hosts of plague appeared to be R. rattus, Otomys angoniensis Wroughton, P. natalensis and Pelomys fallax (Peters). Continuous integrated control of rodents and fleas was recommended, reinforced by quarantine and maintenance of a surveillance service for clinical detection, diagnosis and treatment of patients in the plague endemic area.     

Competition,facilitation or mediation via host? Patterns of infestation of small European mammals by two taxa of haematophagous arthropods

1. We studied the effect of flea infestation on the pattern of tick (Ixodes ricinus and Ixodes trianguliceps) infestation on small mammals. 2. We asked (1) whether the probability of an individual host being infested by ticks was affected by its infestation of fleas (number of individuals and species) and (2) whether the abundance and prevalence of ticks in a host population was affected by the abundance, prevalence, level of aggregation, and species richness of fleas. 3. The probability of a host individual being infested by ticks was affected negatively by flea infestation. At the level of host populations, flea abundance and prevalence had a predominantly positive effect on tick infestation, whereas flea species richness had a negative effect on tick infestation. 4. The effect of flea infestation on tick infestation was generally greater in I. ricinus than in I. trianguliceps, but varied among host species. 5. It can be concluded that the effect of fleas on tick infestation of small mammals may be either negative or positive depending on the level of consideration and parameters involved. The results did not provide support for direct interactions between the two ectoparasite taxa, but suggested population and community dynamics and the defence system of the hosts as possible factors.     

Geographic variation in rodent-flea relationships in the presence of black-tailed prairie dog colonies

We characterized the relationship between fleas and their rodent hosts in the presence of prairie dog colonies and compared them to adjacent assemblages away from colonies. We evaluated the rodent-flea relationship by quantifying prevalence, probability of infestation, flea load, and intensity of fleas on rodents. As prairie dog burrows provide refugia for fleas, we hypothesized that prevalence, flea load, and intensity would be higher for rodents that are associated with black-tailed prairie dog colonies. Rodents were trapped at off- and on-colony grids, resulting in the collection of 4,509 fleas from 1,430 rodents in six study areas. The rodent community composition varied between these study areas. Flea species richness was not different between prairie dog colonies and the surrounding grasslands (p = 0.883) but was positively correlated with rodent species richness (p = 0.055). Prairie dog colonies did not increase the prevalence of fleas (p > 0.10). Flea loads on rodents did not vary between off- and on-colony grids at three of the study areas (p > 0.10). Based on the prevalence, infestation rates, and flea loads, we identified Peromyscus maniculatus, Onychomys leucogaster, and two Neotoma species as important rodent hosts for fleas and Aetheca wagneri, Orchopeus leucopus, Peromyscopsylla hesperomys, Pleochaetis exilis, and Thrassisfotus as the most important fleas associated with these rodents. Prairie dog colonies did not seem to facilitate transmission of fleas between rodent hosts, and the few rodent-flea associations exhibited significant differences between off- and on-colony grids.     

Efficiency of Neopsylla abagaitui fleas as plague vectors in Transbaikalia

Experiments have shown that the block of proventriculus develops in 1.1 to 1.5% of individuals of the flea Neopsylla abagaitui infected with plague microbe. These insects transmit the agent during bloodsucking to different plague carriers (Citellus dauricus, C. undulatus, Meriones unguiculatus, Microtus gregalis). The plague microbe is preserved in fleas for 65 days (the observation period).