云南省34个县市黄胸鼠和褐家鼠体表寄生蚤调查

目的调查云南省黄胸鼠Rattus flavipectus和褐家鼠R.norvegicus体表寄生蚤的感染情况,为云南省鼠疫防控提供科学依据。方法 2012年7月—2013年11月,在云南省34个县市随机选取采样点,笼捕法采集黄胸鼠和褐家鼠,收集并鉴定体表寄生蚤,统计宿主和蚤类物种组成、染蚤率、蚤指数,并根据蚤种组成进行分层聚类。结果采集鼠类842只,其中黄胸鼠714只、褐家鼠128只;共检获体表寄生蚤3227匹,涵盖10个已知蚤种,其中,印鼠客蚤Xenopsylla cheopis和缓慢细蚤Leptopsylla segnis为优势物种。黄胸鼠和褐家鼠的染蚤率分别为48.88%和53.91%,2种鼠的总体蚤指数为3.83匹/只,其中有16个县市的印鼠客蚤指数>1。聚类分析将所有样点聚成3大支系:A支系印鼠客蚤占优势,主要分布于云南省南部地区;B支系优势种不明显或具有其他蚤种,分布于云南省中部地区;C支系缓慢细蚤占优势,分布于云南省北部地区。结论印鼠客蚤和缓慢细蚤是云南省主要蚤种,在接近半数地区印鼠客蚤指数>1,防疫形势非常严峻。云南省黄胸鼠和褐家鼠体表蚤区系组成具有一定的地带性,其中南部地区为印鼠客蚤优势分布区,可视为媒介监测和防控的重点区域。     

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...     

云南省玉龙鼠疫疫源地野外鼠形动物寄生蚤丰盛度影响因素分析

【目的】分析云南省玉龙鼠疫疫源地野外鼠形动物寄生蚤丰盛度的影响因素。【方法】选取云南省玉龙鼠疫疫源地3个海拔区域,按4个季节进行野外捕鼠,捕获的鼠形动物用梳检法收集体表寄生蚤并在显微镜下分类鉴定。通过实际测量和实地观察相结合的方式收集潜在影响鼠形动物寄生蚤丰盛度的因素包括鼠形动物特征变量指标(如种类、年龄、性别、体长、体重)、环境和气象因子(如海拔、季节)等数据。采用EpiData 3.02软件建立数据库,在R软件下使用跨栏负二项分布回归分析鼠形动物寄生蚤丰盛度的影响因素。【结果】从捕获的884只鼠形动物中检获寄生蚤9种484头,以特新蚤指名亚种、方叶栉眼蚤、无值大锥蚤、云南栉眼蚤为主(86.16%)。回归分析显示： 2 700-3 000 m和3 000 m以上海拔鼠形动物染蚤概率较2 400-2 700 m分别增加1.27和3.72倍;湿度高于70%时,鼠形动物染蚤概率较湿度≤70%时减少41%;与齐氏姬鼠的染蚤概率相比,中华姬鼠的染蚤概率降低50%,大绒鼠的染蚤概率增加79%;体长超过104 mm的鼠形动物染蚤概率较体长≤104 mm的鼠形动物染蚤概率增加76%;气温高于15℃时,鼠形动物染蚤数量较温度≤15℃时降低67%;成年鼠形动物的染蚤数量较未成年鼠形动物的染蚤数量增加2.25倍;与春季相比,夏季的染蚤数量增加2.00倍,秋季的染蚤概率减少48%,冬季的染蚤概率和染蚤数量分别增加1.44和1.06倍。【结论】玉龙鼠疫疫源地野外鼠形动物寄生蚤以特新蚤指名亚种、方叶栉眼蚤、无值大锥蚤、云南栉眼蚤为优势蚤种。鼠形动物寄生蚤丰盛度与海拔、季节、气温、湿度等环境气象因子及鼠形动物种类、体长、年龄等鼠形动物特征变量密切相关。     

云南省农耕区小型兽类群落结构及分布格局

为了解云南省农耕区小型兽类群落结构及空间分布特征,根据云南不同经纬度、海拔等自然环境条件,于2010年8月—2018年4月,选取云南省25个调查样区中104块农耕地,采用铗夜法开展小型兽类调查,运用群落生态学指标对农耕区小型兽类的群落特征和沿环境梯度的空间分布进行研究.结果表明: 共捕获小型兽类3240头,隶属4目9科21属42种,其中啮齿目最多,以齐氏姬鼠和黄胸鼠为代表.25个样区聚类为三大类.小兽在纬度和垂直分布上类似,低纬度和低海拔范围的种类相对较少,以家鼠属和小鼠属为主,而高纬度和高海拔地区以姬鼠属、白腹鼠属和绒鼠属为主.小兽物种多样性指数随着海拔的增加呈现先增后降的单峰分布格局,峰值出现在中海拔地区;经度水平分布上,小兽多样性指数呈V型分布格局,在98°—99° E最高;而纬度水平上,小兽多样性指数由南到北总体呈上升趋势.广义可加模型(GAM)分析表明,各因子对农耕区小型兽类多样性指数分布格局的影响程度为经度>海拔>纬度.相似性分析表明,相邻梯度带之间小兽群落结构为中等相似,相似性最高出现在中海拔带、中纬度带、低经度带之间,不同梯度带距离越远,小兽相似性越低.云南省农耕区小兽群落结构在不同维度上存在较高的空间异质性,物种多样性的地理分布随环境梯度变化呈现出不同的分布格局.     

印鼠客蚤的生态习性

<正> 印鼠客蚤Xenopsylla cheopis Rothschild是公认的世界家鼠鼠疫的首要传播媒介,是预防鼠疫的重要监测对象。因此,对其繁殖孳生,季节消长等有关生态习性问题已有较多研究。我们在防疫工作中也作了一些调查工作,现就几个方面综述供参考。 一、宿主 印鼠客蚤的重要宿主是家栖的鼠属(Rattus)鼠种,在云南主要是黄胸鼠和褐家鼠。除此以外,家栖的小家鼠、臭鼩亦有寄生,但并不常见。至于野栖的大足鼠、斯氏家鼠、齐氏姬鼠、大绒鼠、赤腹松鼠、树鼩、黄鼬等,虽有检获记录,但甚为罕见,可认为是家、野鼠类相互交窜,偶然接触所致。 二、吸血习性 如上所说,印鼠客蚤的重要宿主是家栖鼠类,成蚤特别嗜吸家栖鼠类的血当无疑问。至于对已发现寄生的众多野栖动物的刺吸和适应能力,     

苯醚威作用于印鼠客蚤的组织学研究

【目的】通过研究苯醚威对印鼠客蚤 Xenopsylla cheopis (Rothschild,1903)的早 3 龄幼虫和未吸血新羽化成虫的组织学变化,探讨其灭蚤机理,为鼠疫媒介蚤种的防治提供基础资料。【方法】以微量点滴法将苯醚威施药于印鼠客蚤早3龄幼虫和未吸血新羽化成虫,采用组织学、显微摄影及统计学方法观察组织变化。【结果】经苯醚威作用后,印鼠客蚤的早 3 龄幼虫的表皮增厚、卵巢芽生殖细胞萎缩、睾丸芽精原细胞间质减少;未吸血新羽化成虫的睾丸塞消失快、唾液腺细胞破坏严重、中肠上皮细胞萎缩。【结论】(1)苯醚威通过干扰印鼠客蚤幼虫的变态,引起幼虫表皮、生殖芽异常改变,不能发育为成虫而死亡;(2)苯醚威可加速印鼠客蚤新羽化雄性成虫的睾丸塞吸收;(3)苯醚威可破坏印鼠客蚤新羽化成虫的唾液腺细胞,并引起中肠上皮细胞萎缩。     

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     

云南横断山区蚤类物种丰富度与区系的垂直分布格局

为探讨横断山区蚤类物种丰富度与区系垂直分布格局的基本规律以及影响它们分布的主要生态因子,本文以云南西部横断山区18个山峰为主体,对海拔高度在1000–5000m之间已知分布的9科43属142种(亚种)蚤类的垂直分布资料进行综合整理和统计分析。结果显示:(1)蚤类的属丰富度、物种丰富度、特有种丰富度和特有度以及不同区系成分物种丰富度的垂直分布都呈现随海拔先增高后降低的单峰分布格局,最大峰值出现在中山海拔2500–3800m之间;(2)东洋和古北两区系成分物种构成比的垂直分布格局截然不同,前者随着海拔梯度的升高基本递减,后者则随着海拔的升高递增,垂直分布格局反映了它们沿纬度梯度分布的一般规律;(3)聚类分析将横断山9个不同海拔带的蚤类归为6个生态类型,反映出海拔高度、气候环境和森林植被等重要因素对蚤类分布的影响以及蚤类群落的组成、分布沿海拔梯度变化的一般规律,表达了蚤类分布与环境条件的统一性;(4)β多样性沿海拔梯度呈现为双峰形分布格局,两高峰值都反映出蚤类的组成和分布在不同气候环境和植被带之间的过渡与转变,说明β多样性垂直分布格局与海拔梯度上的气候和生境的变化程度有关。研究认为,中山地段物种丰富度高峰的形成主要是由于两大动、植物区系过渡区的边缘效应和山地水湿条件的影响。影响该区域蚤类垂直分布格局的综合因素有山体海拔高度、动植物区系过渡区的边缘效应、山地雨量分配特征、气候环境条件以及人们的生产活动等。     

中国云南人间鼠疫流行区印鼠客蚤在其主要宿主黄胸鼠体表的空间分布格局研究(英文)

中国云南人间鼠疫流行区的主要鼠疫传播媒介是印鼠客蚤。其主要宿主为黄胸鼠。应用Iwao方法及其随机偏离度检验 ,对印鼠客蚤在黄胸鼠的不同个体间的空间分布格局进行了研究。根据Iwao方法建立的印鼠客蚤直线回归模型为 :M =α βM =4 0 0 6 4 2 0 153M ,其中的α和 β均明显高于空间分布判定的界线值 0和 1,经随机偏离度检验 ,F =4 5892 ,P <0 0 5。结合α ,β值及随机偏离度检验结果 ,印鼠客蚤在其主要宿主黄胸鼠体表的空间分布型被判定为聚集型分布。印鼠客蚤这种聚集型分布意味着该蚤的个体分布不均匀 ,而是在宿主动物体表形成大小不等的聚集蚤群。印鼠客蚤在黄胸鼠不同个体间的这种不均匀分布提示 :即使接触同一种染疫鼠类动物 ,因鼠体蚤分布极不均匀 ,其传播机会是不均等的。     

武陵山东部蚤类区系及不同样地群落物种多样性比较

于2000～2004年对武陵山东部7个不同样地、3个不同海拔梯度和6个不同生境类型的蚤类,进行了5年调查与研究.结果:1)在获得的7科17属30种4 320只蚤类中,有4种为古北界种类,占13.33%,22种为东洋界种类,占73.34%,4种为广布种,占13.33%;该结果与云南无量山及临沧地区的蚤类有着相同或相似的区系渊源,而与一江之隔的大巴山东部地区区系则明显不同,该地区以古北界成分为优势;2)武陵山东部地区蚤类的垂直分布规律主要表现在,1 100 m以下主要为东洋界成分,1 200 m以上有少量古北界种类分布,并随海拔升高,古北界成分略有增加;3)在7个不同样地中,物种丰富度和个体数量随海拔升高而增加,在优势种上,多数样地以偏远古蚤为优势,但在优势数量上缺乏明显规律性,并不是随海拔升高而增加;4)在6个不同生境类型中,优势种与优势数量都具明显的规律性,其中以偏远古蚤为主分为两组,山脊侧缘林、小溪山边林和坡地林为一组,人工林和农田山侧灌木林为另一组,前者平均优势数量达80.03%,后者优势数量在31.56%～48.92%之间;5)相似性系数(q值):在整个山体多数样地中,由北向南相似性系数(q值)随海拔降低和空间距离增大而逐渐降低,仅绿丛坡与牛庄、绿丛坡与独岭有例外,表明整个山体植被的片断化、或斑块化,一方面加剧或减低了样地与样地之间蚤类群落的相似程度,另一方面还要受海拔及空间距离的双重影响与制约,即海拔高度和空间距离愈大,蚤类群落的相似性及多样性越低,山体的片断、斑块或破碎化就越明显,这显然与人为过多或过频干扰有关.     

云南蚤类区系及分布特征

【目的】在收集汇总以往野外调查资料以及已经发表的历史文献资料基础上,归纳云南蚤类的分布特点,分析云南地理小区对蚤类的影响。【方法】在实地采集和补充文献记录基础上,对收集到的蚤类进行系统分类整理;运用SPSS13.0的主成分分析及系统聚类对数据进行处理。【结果】本研究共记录云南蚤类9科45属144种,其中古北种15种,东洋种 108种,东洋、古北两界兼有种15种,广布种6种。144种蚤中,属于云南特有蚤类有75种;横断山中部小区记载蚤类122种,横断山南部小区26种,滇东高原小区41种,滇西高原小区28种,滇南山地小区25种。主成分分析和聚类分析结果基本一致,均可聚为两类：一类为横断山南部小区、滇南山地小区、滇西高原小区及滇东高原小区; 另一类为横断山中部小区。【结论】云南省蚤类分布明显受到地理小区环境的影响。云南省蚤类昆虫种类繁多,蚤类的自然分布受到云南省特定地形地貌影响。     

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.     

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.     

Patterns of diversity and abundance of fleas and mites in the Neotropics: host‐related,parasite‐related and environment‐related factors

The effects of host‐related, parasite‐related and environmental factors on the diversity and abundance of two ectoparasite taxa, fleas (Insecta: Siphonaptera) and mites (Acari: Mesostigmata), parasitic on small mammals (rodents and marsupials), were studied in different localities across Brazil. A stronger effect of host‐related factors on flea than on mite assemblages, and a stronger effect of environmental factors on mite than on flea assemblages were predicted. In addition, the effects of parasite‐related factors on flea and mite diversity and abundance were predicted to manifest mainly at the scale of infracommunities, whereas the effects of host‐related and environmental factors were predicted to manifest mainly at the scale of component and compound communities. This study found that, in general, diversity and abundance of flea and mite assemblages at two lower hierarchical levels (infracommunities and component communities) were affected by host‐related, parasite‐related and environmental factors, and compound communities were affected mainly by host‐related and environmental factors. The effects of factors differed between fleas and mites: in fleas, community structure and abundance depended on host diversity to a greater extent than in mites. In addition, the effects of factors differed among parasite assemblages harboured by different host species.     

Diversity and distribution of parasitic angiosperms in China

Parasitic plants are an important component of vegetation worldwide, but their diversity and distribution in China have not been systematically reported. This study aimed to (1) explore floral characteristics of China's parasitic plants, (2) map spatial distribution of diversity of these species, and (3) explore factors influencing the distribution pattern. We compiled a nationwide species list of parasitic plants in China, and for each species, we recorded its phylogeny, endemism, and life form (e.g., herb vs. shrub; hemiparasite vs. holoparasite). Species richness and area‐corrected species richness were calculated for 28 provinces, covering 98.89% of China's terrestrial area. Regression analyses were performed to determine relationships between provincial area‐corrected species richness of parasitic plants and provincial total species richness (including nonparasitic plants) and physical settings (altitude, midlongitude, and midlatitude). A total of 678 species of parasitic angiosperms are recorded in China, 63.13% of which are endemic. Of the total, 59.73% (405 species) are perennials, followed by shrubs/subshrubs (14.75%) and vines (1.47%). About 76.11% (516 species) are of root hemiparasites, higher than that of stem parasites (100, 14.75%), root holoparasites (9.00%), and endophytic parasites (0.15%). A significant positive relationship is found between the area‐corrected species richness and the total species richness, which has been previously demonstrated to increase with decreasing longitude and latitude. Moreover, more parasitic species are found in the southwest high‐altitude areas than low areas. Consistently, the area‐corrected species richness increases with increasing altitude, decreasing latitude, and decreasing longitude, as indicated by regression analyses. China is rich in parasitic flora with a high proportion of endemic species. Perennials and root hemiparasites are the dominant types. The spatial distribution of parasitic plants is largely heterogeneous, with more species living in southwest China, similar to the distribution pattern of Chinese angiosperms. The positive relationship between parasitic and nonparasitic plant species richness should be addressed in the future.     

Analysis of ectoparasites (chigger mites,gamasid mites,fleas and sucking lice) of the Yunnan red‐backed vole (Eothenomys miletus) sampled throughout its range in southwest China

The Yunnan red‐backed vole Eothenomys miletus (Rodentia: Cricetidae) is an endemic rodent species and reservoir host of zoonoses in southwest China. Based on a large host sample (2463 voles collected from 39 localities between 2001 and 2013), a general analysis of four categories of ectoparasite (fleas, sucking lice, chigger mites and gamasid mites) on E. miletus across its entire range of distribution was made. This analysis identified a total of 71 895 ectoparasites belonging to 320 species (30 species of flea, 9 of sucking louse, 106 of gamasid mite and 175 of chigger mite) with a high prevalence (87%), mean abundance (29.19) and mean intensity (33.69). Of the 18 vector species of zoonoses found on E. miletus, the flea Ctenophthalmus quadratus (Siphonaptera: Hystrichopsyllidae) and chigger mite Leptotrombidium scutellare (Trombidiformes: Trombiculidae) were the dominant species; these are the main vectors of zoonoses in China. All of the dominant parasite species showed an aggregated distribution pattern. Male voles harboured more species of parasite than females. Chigger mites represented the most abundant species group on voles and their prevalence was positively correlated with mean abundance (r = 0.73; P < 0.05). As a single rodent species, E. miletus has a high potential to harbour abundant ectoparasites with high species diversity and high rates of infestation. The sex of the vole affects ectoparasite infestation.