闽南淡水螺寄生吸虫幼虫期的调查

本文报道在闽南的漳平、龙海、南安检查了四种淡水螺(耳萝卜螺、放逸短沟蜷、纹沼螺、瘤拟黑螺)共2532只,经检查有13种吸虫的幼虫期,并对其中的中华唐似吸虫和二种异形种吸虫进行了动物感染实验,结果于后。一、中华唐似吸虫Tangiopsis chinensis地点;漳平。放逸短沟蜷(Semisulcospira li-bertlna)是新查见的宿主,感染率为2.5%(32/1264)。螺体内查见雷蚴和尾蚴。该蜷以其尾蚴感染介蚤和剑水蚤均未成功。二、包氏毛毕吸虫Trichobilharzia paoi地点:龙海、南安。耳萝卜螺(Radix auri-cularia)感染率为4.56%(24/526)。在螺体内发现其胞蚴和尾…     

香港淡水及海产贝类感染吸虫幼虫期的调查研究

作者于1983年4月及1986年4月二次在香港检查该地区20个村庄11种淡水螺(共11680粒),及14个海区包括红树林地带和无红树林的海滩中的22种海产贝类(共12580粒)。查获26种吸虫幼虫期,其中12种见于淡水螺(5种〕,8种寄生于红树林地带的海螺(7种),5种寄生于无红树林海区的贝类(6种),1种见于在红树林地带和无红树林海滩生存的海螺(5种)。寄生淡水螺的吸虫幼虫期分隶于Cortrematidae;Maseniidae;Schistosomatidae;Notocotylidae;Strigeidae;Paramphi-stomidae;Plagiorchidae;Philophthalmidaes;Microphallidae及Heterophyidae等科。寄生于海产贝类的吸虫幼虫期分隶于Philophthalmidae; Heterophyidae;Fellodistomidae; Cyathoco-tylidae;Echinostomatidae;Opecoelidae等科及Plagiorchioidea总科。     

外睾吸虫幼虫期的早期发育及贝类宿主淋巴细胞的反应

日本血吸虫病的媒介钉螺也是外睾吸虫的中间宿主。本文报告外睾吸虫早期幼虫在钉螺及窄口螺的寄特发育形式及贝类宿主的反应情况。贝类宿主吞食外睾吸虫虫卵后１２天,毛蚴体体中的胚细胞已穿过宿主胃肠壁分散在其外围组织中。螺体在其头颈部产生大量血淋巴细胞并下行到内脏团包围虫体的胚细胞。生存的虫体胚细胞分散地通过宿主循环系统被送到消化腺及生殖腺的间隙中发育成早期雷蚴胚球。在雷蚴胚球周围尚有开始消退的宿主血淋巴细胞     

淡水螺类与人们的关系

我国幅员辽阔,江河、湖泊、沟渠、池塘等淡水水域星罗棋布。在这些不同的水域内,分布着多种多样的螺类。它们与人们的关系密切,利害兼有。有益的可供人们食用或药用,或作家畜、家禽和鱼类的饲料。但其大多数是对人们有害的,如有些螺是人体、家畜、家禽和鱼类寄生吸虫的中间宿主,许多吸虫病的发生和蔓延都与这些螺类的分布有关。另外有个别种类还可使江河沿岸的工业管道堵塞,影响生产。现将对人们     

内蒙东部地区绵羊中华双腔吸虫生物学和流行病学的研究

中华双腔吸虫(Dicrocoelium chinensis Tang et Tang,1978)的生活史虽经研究,但本吸虫在第二中间宿主及终末宿主体内发育的情况尚未经阐明(唐崇惕等,1980).内蒙科右前旗附近数个旗县是本吸虫的流行区,1980—1981年我们在那里进行本项工作,从     

福建省淡水蟹类的调查研究

福建全省多山地丘陵,海拔一般在200—1,200公尺上下,溪流纵横交错,气候温湿多雨,年平均气温18—22℃。这些自然条件极其适宜于淡水蟹类的生长繁殖。因此该省溪蟹在种类及数量上都较为丰富。 为了对该省淡水蟹类进行分类研究,同吋调查肺吸虫囊蚴在不同种别溪蟹体內的感染率及感染强度,1977年6—8月中国科学院动物研究所及福建省卫生防疫站在邵武、屏南、福州北峰、永春、靖城、龙岩及连城七个县市协同进行了工作。兹将本省淡水蟹类的种类组成,地理分布,生态特点叙述如下。有关不同蟹种感染肺吸虫囊蚴的情况则另行报道。     

四川省淡水蟹类的调查研究

近几年来,我们在四川省主要肺吸虫病流行地区采集了大量蟹类标本,现已初步鉴定出淡水蟹类7种,隶属于2属1科,其中有城口华溪蟹Sinopotamon chengkuense、峨边华溪蟹S.ebianense两个新种。四川西部为高原和高山峡谷区与成都平原和川中丘陵的交接和过渡地区,地形复杂,河流山溪纵横,海拔高度相差悬殊,地理隔离现象显著,为动植物种群繁多的地带,也是华溪蟹属种类分化较多的地区。这里除有峨边华溪蟹一个新种外,其他还有光泽华溪蟹、锯齿华溪蟹、雅安华溪蟹和灌县华溪蟹等共5种,约占四川蟹类总数的80%,它们都主要集中分布在岷江水系,除锯齿华溪蟹…     

倪氏复口吸虫和湖北复口吸虫生活史的研究Ⅰ．早期幼虫的实验生态

本文比较研究了倪氏复口吸虫(Diplostomum niedashui pan＆Wang)和湖北复口吸虫(Diplostomum hupehensis pan＆Wang)早期生活史的实验生态,包括温度、光照度对它们直接和间接的影响及某些数量的变化。     

Rapid colonisation of Lymnaea stagnalis by larval trematodes in eutrophic ponds in central Europe

High recruitment rates of multiple species and hierarchical competition are the keys to a competitive exclusion model of community assembly in larval trematode communities in molluscs. Eutrophic environments provide conditions for accelerating trematode transmission and this would increase the strength of interspecific interactions. To test these predictions, we provide the first known assessment for a pulmonate snail host, and for highly productive aquatic environments, of the rates of colonisation and extinction at the level of individual snail host patches, of a large guild of trematode species. Using a uniquely large dataset from a relatively long-term mark-recapture study of Lymnaea stagnalis in six eutrophic fishponds in central Europe, we demonstrate extraordinarily rapid colonisation by trematodes of a snail host, thus meeting the assumptions of the competitive exclusion model. Overall annual colonisation rates ranged from 243% to 503% year⁻¹ so that the odds of trematode establishment in an individual snail in these ponds are two to five times per year. Extinction rates were substantially lower than colonisation rates and, therefore, would not result in turnover rates high enough to significantly affect prevalence patterns in the snail populations. At the species level, analyses of sample-based estimates of probabilities of colonisation revealed that shared species traits associated with transmission and competitive abilities determined the limits of colonisation abilities. Colonisation rates were exceedingly high for the species transmitted to the snails passively via eggs. There was a significant effect of species competitive abilities on colonisation rates due to subordinate species being substantially better colonisers than both strong and weak dominants, a pattern consistent with the predictions of the competition-colonisation trade-off hypothesis. Our results suggest that, with the extraordinarily high trematode colonisation potential in the area studied, the spatial and temporal patterns of intraspecific heterogeneity in recruitment may provide conditions for intensification of interspecific interactions so that complex community assembly rules may be involved.     

长尾蚴吸虫幼虫在菲律宾蛤仔的寄生部位及其组织化学的研究

本文报道长尾蚴吸虫幼虫在菲律宾蛤仔的寄生部位及其组织化学的研究,长尾蚴吸虫幼虫主要寄生于哈仔的生殖腺组织中,仅少部分进入生殖腺附近的消化腺,鳃等。受感染严重的蛤仔,其生殖腺的滤泡等组织被虫体占满并被耗尽,长尾蚴吸虫子胞蚴的胞壁及尾蚴的皮导主要含碱性蛋白质和粘蛋白,子胞蚴的胚球,尾蚴的吸盘,生殖原基,单细胞腺体主要ＤＮＡ阳性物质,排泄囊含丰富的碱性蛋白质;尾蚴体的中部含有呈颗粒团的粘蛋白和抗淀粉酶的     

Echinostome infection in green frogs (Rana clamitans) is stage and age dependent

The increasing threat of emerging infectious diseases in both wildlife and humans has spurred interest in the causes of disease emergence, including the role of anthropogenic change. A prior field study of infection patterns in amphibians suggests that echinostome infection may be an emerging disease of green frogs Rana clamitans living in urbanized environments. We examined the impact of echinostome infection on green frog tadpoles at a wide range of developmental stages (Gosner stage 25–39). Echinostome infection was associated with green frog mortality rates of up to 40% in an early developmental stage, and none in later developmental stages. Tadpoles exposed to higher echinostome doses exhibited higher edema rates, a potential sign of compromised renal function. Histopathological analysis further supported the hypothesis that echinostome-induced tadpole mortality resulted from compromised renal function. Given that the timing of highest cercarial shedding can coincide with the most vulnerable stages of green frog tadpole development, echinostomes could significantly impact green frog survival in nature.     

SELF-FERTILIZATION VERSUS CROSS-FERTILIZATION IN THE HERMAPHRODITIC FRESHWATER SNAIL BULINUS GLOBOSUS

Self-fertilization depression of fitness in the freshwater hermaphroditic snail Bulinus globosus, an intermediate host of the parasitic trematode Schistosoma, has been studied in a strain originating from Niger. B. globosus is an outcrosser that can self-fertilize when isolated before any copulation has occurred. The self-fertilization depression has been estimated during two successive generations. In the first generation, selfing was compared to outcrossing. Within each mating system group, selfing and outcrossing were compared again in the second generation. A striking difference was shown in favor of cross-fertilization for the number of eggs laid, the survival at birth of young snails and the number of snails reaching sexual maturity. The overall self-fertilization depression is 0.920 after two generations of selfing. We discuss the relative role of selfing and outcrossing in the evolution of freshwater snail populations.     

田螺科五种螺的核型研究

以早期胚胎细胞为材料,用火焰干燥法制片,对分布于我国湖北省武汉市近郊的常见田螺科(Viviparidae)五种螺的核型进行了分析。结果:两种圆田螺的染色体数和国外报道的同一属的种类的一致。而三种环棱螺的染色体数,则较国外报道的另两种的少得多。在铜锈环棱螺的核型中,其m组的第一对和sm组的第四对染色体上,具有明显的随体,出现频率甚高。     

酸性水对淡水螺类存活,生长与繁殖的影响

研究了酸性水对椭圆萝卜螺和铜锈环棱螺等淡水螺类存活、生长及繁殖的影响。结果表明,椭圆萝卜螺对低pH值的耐受能力,96小时LC_(50)值为pH3.96。pH值低于5.0时,淡水肺螺类产的卵袋数量较少,卵孵化时间较长,幼螺生长较缓慢。铜锈环棱螺仔螺在低pH(对照组)下生长到第35和45天时,其体长生长率分别为1.21和1.07％,而pH5.0组则仅有0.18和0.29％。pH5.5对淡水肺螺类无明显影响,pH3.0则不能生存。