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…     

雅安哺乳动物的几种棘口吸虫

1989年3—9月,用分离白雅安淡水螺体内的棘口吸虫囊蚴按100—150个/只人工感染小白鼠15只,在小白鼠的胃和肠道共检到5种棘口吸虫,现报道于下:(测量单位:mm)1曲领棘缘吸虫Echinoparyphium recurvatum第二中间宿主为赤豆螺Bithynia fuchsiana和中华圆田螺Cipangopaludina cathayen。2接睾棘口吸虫Echinostoma paraulum Dietz,1909(宫川棘口吸虫E.miyagawai Ishii,1932)第二中间宿主为尖口圆扁螺Hippeuties cantori。3鼠真缘吸虫Euparyphium murinum第二中间宿主为赤豆螺和中华圆田螺。4移睾棘口吸虫E.cinetorchis第一中间宿主为赤豆螺;第…     

福建真马生尼亚吸虫Eumasenia fukienensis sp.nov.新种描述及其生活史的研究

1.本文详细描述了福州地区胡子鲶肠管中极常见的一种真马生尼亚吸虫的形态构造,由于福建标本在虫体的大小,围口棘圈中棘的数目、大小,腹吸盘位置,前咽及食道的长度,肠管盲端到达的位置,卵巢、睾丸所在的位置,以及其相关的大小,前列腺管基部的构造,以及排泄囊的形状等,和文献上已记述的虫种差别很大。因此我们为其定名为福建真马生尼亚吸虫Eumasenia fukienensis sp.nov.。 2.本文详细描述了本种吸虫虫卵、毛蚴以及在三种扁螺类:凸旋螺Gyraulus conve-xiusculus Hutton;肯氏圆扁螺Hippeutis cantori Benson和半球隔扁螺Segmentina hemis-phaerula (Benson)体内发育的二代胞蚴、尾蚴以及囊蚴等各幼虫期的形态。 3.本文对本种吸虫在系统发生上和斜睾科吸虫的亲缘关系进行讨论。     

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     

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。     

北京地区家禽体内棘口科(Echinostomatidae)几种吸虫的初步研究

寄生于北京地区的家鸭、家鸡与家鹅体内的棘口科(Echinostomatidae Dietz,1909)吸虫共获得12种,隶属于2亚科:1.棘口亚科(Echinostomatinae Odhner,1910)计有2属:(1)棘口属(Echinostoma Rudolphi,1809)有8种,其中2种为国内新纪录与1种未定名种。(2)棘绿属(Echinopharyphium Dietz,1909)有3种,其中1种新种与1种未定名种。2.低颈亚科(Hypoderaeina Skrjabin et Baschkirova,1956)只有1属1种。 卷棘口吸虫与似锥低颈吸虫的感染率最高,感染强度也较大(接睾棘口吸虫最大)。 宿主以家鸭体内的吸虫种类为多,计有11种,家鸡与家鹅体内仅获得2—3种,寄生部位棘口亚科以大肠为主,而低颈亚科以小肠为多。 感染率一般较昆明与福建为低。 文中附有鸭、鸡与鹅三种家禽的棘口吸虫属与棘缘吸虫属的检索表以及名录和分布地区。     

福建腹口吸虫种类及生活史的研究

一、前言 腹口类吸虫由于其口孔开在身体腹面中央部位而不同于所有口孔开在前端的复殖类吸虫。本类吸虫的各幼虫期,如具纤毛棒的毛蚴、分支的胞蚴以及牛首状的尾蚴等特征也和前口类吸虫的各幼虫期有显著的差别。自从1819年Rudolphi发现腹口吸虫至今世界各地报道的种类已有一百七十余种,但是,在这许多种类中,进行过生活史研究的只有十     

滨鹬马蹄吸虫(复殖目:微茎科)的尾蚴和囊蚴期的季节动态

对科威特湾微茎科滨鹬马蹄吸虫幼虫期的中间宿主双带盾桑椹螺(Clypeomorus bifasciata)及小相手蟹(Nanosesarma minutum)的季节动态进行了研究。调查期超过一年,在检查的1 600只螺和415只蟹中, 11.8 %的螺感染了8种马蹄属线虫中的一种,且以滨鹬马蹄吸虫的感染占优势(9.9 %螺感染) ; 80 %的蟹感染滨鹬马蹄吸虫囊蚴。虽然一年四季两种宿主都会感染,但吸虫的流行和尾蚴(指成熟期感染)在夏季呈现高蜂。从螺体排出的尾蚴具有明显季节性,在此海湾必须要超过最低温度20℃。总的感染率在较大(较老)的螺里有所下降,显示吸虫影响宿主生存并随之影响宿主群体结构。囊蚴的感染丰度与蟹的个体大小有明显相关性;较大的蟹感染较多的囊蚴,显示宿主能耐受更多的吸虫。调查显示,囊蚴的感染率与蟹的大小或性别无相关性。囊蚴体外脱囊以及产卵吸虫的释放证明,成熟虫体终年存在于所有大小和性别不同的蟹里,显示从蟹到鸟的持续感染是可能的。总的来说,滨鹬马蹄吸虫在海湾的传播动态是由这两种无脊椎动物宿主来协调,并似乎是被一系列依赖于温度的活动控制,这些活动影响易感宿主种群及感染性幼虫期尾蚴和囊蚴的存在。     

雅安地区棘口科吸虫及其中间宿主的研究

作者于1989年3—9月在雅安通过解剖检查13种贝类12628只并将其体内的棘口科吸虫囊蚴人工感染实验动物(家鸭、小白鼠)共检获12种棘口科吸虫,棘口科吸虫尾蚴在第一中间宿主体内的季节性消长亦经观察。并对棘口科吸虫囊蚴与贝类以及贝类与鸟禽类和嚯乳类动物间的相互关系作了讨论。     

鄱阳湖鱼类的寄生吸虫Ⅱ.棘口科、发状科和血居科四新种记述

作者在整理1975年以来所采集的鄱阳湖鱼类的寄生吸虫时,除独睾科(MonorchiidaeOdhner,1911)已记述三新种外,尚有棘口科(Echinostomatidae Dietz,1909)二种、发状科(Gorgoderidae Looss,1901)和血居科(Sanguinicolidae Graff,1907)各一种,系文献未曾记载过。虫体描述系根据活体标本及盐酸卡红整体染色制片标本观察、测量(单位:毫米)。模式标本存江西省寄生虫病研究所。     

Trematode diversity in freshwater snails from a stopover point for migratory waterfowls in Hokkaido,Japan: An assessment by molecular phylogenetic and population genetic analyses

The cryptic diversity of trematodes was evaluated in the Nagayama-Shinkawa River, an artificial canal of the Ishikari River System of Hokkaido, Japan. Numerous migratory waterfowls use the canal as a stopover point in every spring season. The lymnaeid snail, Radix auricularia, and the semisulcospirid snail, Semisulcospira libertina, colonize the static and flowing water areas, respectively. The trematode fauna of the two snails was assessed by molecular phylogenetic and population genetic analyses. Each of distinctive clades in mitochondrial DNA trees was arbitrarily set as a species. In total, 14 species of the families Diplostomidae, Echinostomatidae, Notocotylidae, Plagiorchiidae, and Strigeidae occurred in R. auricularia, wherease S. libertina harbored 10 species of the families Echinochasmidae, Heterophyidae, Notocotylidae, and Lecithodendridae and Cercaria creta, an unclassified species whose adult stage is still unknown. The species diversity of the larval trematodes could be recognized as a “hot spot”, suggesting that the seasonal visit of waterfowls is very important to spread trematodes and to keep their diversity. A high intraspecific genetic diversity was observed in the echinostomatid, notocotylid, echinochasmid, and heterophyid species, whose definitive hosts include birds. It seems likely that each of the parasite populations is always disturbed by repeated visits of waterfowls.     

Notocotylus ikutai n. sp. (Digenea: Notocotylidae) from lymnaeid snails and anatid birds in Hokkaido,Japan

An unknown species of the genus Notocotylus (Digenea: Notocotylidae) was found as the larval stage from the lymnaeid snail, Radix auricularia, in a static water area of the Chubetsu River, Hokkaido, the northernmost island of Japan. A DNA barcoding identification system was applied to detect the adult stage. Through the inspection of anatid game birds in Hokkaido, Anas crecca, Anas platyrhynchos, Anas zonorhyncha, and Mareca penelope were demonstrated to serve as the definitive hosts. The detailed morphological features of the species were characterized using adults raised experimentally in immunosuppressed mice and naturally developed larvae in R. auricularia. Although the species is morphologically similar to Notocotylus attenuatus and Notocotylus magniovatus in both adult and larval stages, its taxonomic independence was confirmed by a comprehensive study based on molecular phylogeny, morphology, and ecology. Here we propose Notocotylus ikutai n. sp. for this species. The migratory behavior of the anatid hosts and the North-Eurasian distribution of R. auricularia suggest that the new species is widely distributed in the northern Far East.     

Strigeoid trematodes of Malaysia with descriptions of a new genus and three new species.

Six species of strigeoid trematodes are reported from Malaysia. One new genus and 3 new species are described: Apatemon (Apatemon( jamesi sp. n (Strigeidae); cercaria Cotylurus sullivani sp. n. (Strigeidae); Neodiplostomum (Neodiplostomum) sp. (Diplostomatidae); Fibricola ramachandrani (Diplostomatidae); Pseudoscolopacitrema otteri gen. n. et sp. n. (Diplostomatidae); and cercaria Cyathocotyle malayi sp. n. (Cyathocotylidae). The life cycles of A. jamesi and C. malayi have also been investigated.     

The role of bithyniid snails (Gastropoda: Bithyniidae) as hosts of trematodes of the family notocotylidae in ecosystems of different climatic zones of the West Siberian Plain

The results of long-term investigations (1994–2012) of an infection rate of trematodes of the family Notocotylidae Lühe, 1909 in the first intermediate hosts (Bithyniidae family) are discussed. The bithyniid snails (11348 Bithynia troscheli (Paasch, 1842) and 4347 Bithynia tentaculata (Linne, 1758) in 1994–2012 from Western Siberia have been studied. Parthenitae and cercariae of the family Notocotylidae belong to three species: Notocotylus imbricatus Looss, 1894, Szidat; N. parviovatus Yamaguti, 1934 [syn.: N. chionis Baylis, 1928] and Catatropis verrucosa (Frohl.) Odhner, 1905. The extensiveness of infection of bithyniid snails by the tre-matodes (parthenitae and cercariae) of the family Notocotylidae in rivers basin Ob, Irtich, Karacyk and Chany Lake is analysed. The level of the infection of bithyniid snails by trematodes (parthenitae and cercariae) does not exceed one percent in different reservoirs. The similar data have been obtained during long-term studies in the estuare of the Kargat river, and in the Ob river (near Novosibirsk). The percentage of infected B. tentaculata was significantly higher than of infected B. troscheli in the total (1.79 and 0.32% accordingly, χ² = 95.1, p < 0.001), and in different reservoirs, too. The infected bithyniid snails are recorded in waterbodies of all four basins only in steppe (0.52 ± 0.37%) and forest-steppe zones (0.76 ± 0.07%). Bithyniid snails from waterbodies of the forest zone of the West Siberian Plain were not infected with parthenitae and cercariae of the family Notocotylidae.     

洞庭湖外睾吸虫新种及其生活史

本文报告洞庭湖区鲶鱼肠道寄生的洞庭湖外睾吸虫Exorchis dongtinghuensis sp.nov(新种)及其全程生活史,其第一中间宿主为湖北钉螺Oncomelania hupensis;第二中间宿主为鲤鱼、鲫鱼和金鱼;终宿主为鲶鱼Parasilurus asotus。作者对各期宿主作了人工感染试验和现场自然感染调查。对其发育过程作了观察比较。     

Parthenites and cercaria of trematodes in the snails Lymnaea saridalensis (Gastropoda, Pulmonata), which inhabits the watershed area of Chany Lake (the South of Western Siberia)

The full list of parthenogenetic larvae and cercaria is presented for the first time for the freshwater snail L. saridalensis (Gastropoda, Pulmonata), which inhabits the watershed area of Chany Lake. It was found that this snail species plays a significant role as the first intermediate host in the life cycles of trematodes in the southern part of Western Siberia. The invasion parameters were calculated for different parasite species. It was found that 50% of the L. saridalensis population serves as the first intermediate host for eleven trematode species that belong to six families: Plagiorchiidae, Echinostomatidae, Diplostomatidae, Strigeidae, Notocotylidae, and Schistosomatidae. The prevalence of infection by each trematoda species in L. saridalensis was determined. Five species of trematodes from the Plagiorchiidae and Echinostomatidae families formed the center of the parasite community, viz., the species Plagiorchis elegans, P. mutationis, Opisthioglyphe ranae, Molinella anceps, and Echinoparyphium aconiatum. Two species, Plagiorchis mutationis and P. multiglandularis, were recorded in the studied area (the Chany Lake watershed area) for the first time at the stages of parthenite and cercaria. It was also found that 1% of L. saridalensis population have multiple (mostly two-species) infections.     

Impact of trematode parasitism on the fauna of a North Sea tidal flat

The impact of larval trematodes on the fauna of a North Sea tidal flat is considered at the individual and at the population level, depicting the digenean parasites of the common periwinkle,Littorina littorea, and their life cycles, as an example. On the German North Sea coast,L. littorea is first intermediate host for 6 larval trematodes representing 6 digenean families —Cryptocotyle lingua (Heterophyidae),Himasthla elongata (Echinostomatidae),Renicola roscovita (Renicolidae),Microphallus pygmaeus (Microphallidae),Podocotyle atomon (Opecoelidae) andCercaria lebouri (Notocotylidae). All exceptP. atomon utilize shore birds as final hosts; adultP. atomon parasitize in the intestine of teleosts, mainly pleuronectid flatfish. Second intermediate hosts ofC. lingua are various species of fish; the cercariae ofH. elongata encyst in molluscs and polychaetes, those ofR. roscovita in molluscs;M. pygmaeus has an abbreviated life cycle;C. lebouri encysts free on solid surfaces; and the fish trematodeP. atomon utilizes benthic crustaceans, mainly amphipods, as second intermediate hosts. On the tidal flats of the Königshafen (Sylt), up to 77% of the periwinkles have been found to be infested by larval trematodes. Maximum infestations in individual samples were 23% forC. lingua, 47% forH. elongata and 44% forR. roscovita. The digeneans cause complete parasitic castration of their carriers and hence exclude a considerable proportion of the snails from the breeding population. Infestation reduces the longevity of affected hosts, and size-related, trematode-induced differential mortality causes changes in the normal size-frequency distribution of individual snail-age classes. Young flatfishPleuronectes platessa from the Königshafen are 100% infested with metacercariae ofC. lingua. Heavy infestation of the gills causes obstruction of blood vessels and respiratory impairment; metacercariae in the eyes and optic nerves cause visual and neurological disturbances. A single metacercaria is sufficient to kill a larval fish.Mytilus edulis andCardium (Cerastoderma) edule are 100% infested with metacercariae ofH. elongata. Heavy infestation impairs the byssus-thread production in mussels and affects the burrowing ability of cockles. Longevity and resistance to environmental — particularly thermal — stress are reduced in bivalves infested withH. elongata andR. roscovita. There is evidence that, in the study area, population size and age composition of the molluscs discussed are (indirectly) controlled by trematode parasites employing sea birds as final hosts, rather than directly by the predatory activities of these birds.     

Component community of larval trematodes in the mudsnail Hydrobia ventrosa: temporal variations in prevalence in relation to host life history

Temporal variations in the prevalence of larval trematodes in the short-lived prosobranch mudsnail Hydrobia ventrosa (Montagu) were investigated in relation to host life history and season for 4 successive years in temperate windflats of the southern Baltic Sea. The component community of trematode larvae in H. ventrosa comprises at least 10 species; families (and species) represented include Notocotylidae (1), Echinostomatidae (1 or 2), Heterophyidae (2), Monorchidae (1), Microphallidae (3 or 4), Psilostomatidae (1), and Hemiuridae (1). The notocotylid Paramonostomum alveatum was the most prevalent species, followed by the microphallids Maritrema subdolum and Microphallus sp. Trematode prevalence in H. ventrosa fluctuated seasonally. Prevalence usually peaked in summer between July and September-October and decreased in late winter-early spring. This seasonal change is chiefly explained by the life history patterns of the semelparous snail host. Hydrobia ventrosa has a maximum life span of about 2 yr and reproduces between June and November of its second calendar year. The first trematode infections appeared annually in May when the most abundant cohort of H. ventrosa, the second-calendar-year snails, mature. The prevalence continued to increase until August-September, throughout the reproductive period of the second-calendar-year snails, Prevalence decreased during winter, when most of the second-calendar-year snails died after reproduction. On the basis of longterm laboratory experiments, it has been shown that the late autumn-winter mortality was not the result of trematode infections. Seasonal patterns of prevalence were similar among the trematode species except for the monorchid Asymphylodora demeli, the only one using fish definitive hosts. Species-specific differences in the seasonal occurrence of prepatent infections and the predominance of certain larval stages in winter are interpreted as different strategies of the trematode species to survive the harsh winter conditions, or to survive the death of the first intermediate host in autumn-winter, or both.