安徽省泾县发现缩小膜壳绦虫和链形多头绦虫幼

1985—1986年,我们在泾县包合乡血吸虫病流行病学调查中,发现有可感染于人的缩小膜壳绦虫(成虫)及其终宿主黑线姬鼠、黄胸鼠和链形多头绦虫(蚴虫)及其中间宿主野兔,是安徽省的新发现。 一、缩小膜壳绦虫(长膜壳绦虫)[Hymenolepis diminuta]取自1985年1月15日和1986年1月15日采到的两只黑线姬鼠(Apodemus agrarius),和1986年1月13日采到     

黄鼠栉带绦虫和梳状莫斯绦虫的生活史研究

本文首次阐明黄鼠栉帮绦虫和梳状莫斯绦虫的生活史。实验证明这二种绦虫的中间宿主同是曲愎翼甲螨和小型肋甲螨。二者绦虫的成虫、拟囊尾蚴的形态特征有详细的描述与比较。此外,作者简要地讨论了spassky(1951)的锡带属、栉带属和莫斯属等的分类问题。     

湖北部分地区鼠体膜壳绦虫调查

1982～1985年我们在湖北的通山县、应城县、天门县、宜昌县及神农架林区对寄生鼠体而与人有关的微小膜壳绦虫Hymenolepis nana和缩小膜壳绦虫Hymenolepis dininuta及鼠体外寄生蚤类进行了调查。方法将捕到的鼠进行编号,种类鉴定,解剖观察。如阳性取出虫体鉴定虫种。对鼠体外寄生蚤进行收集并鉴定种类,观察体内是否有自然感染的似囊尾蚴。结果在582只鼠中共检出阳性鼠165只,阳性率28.3%。其中微小膜壳绦虫的阳性率为11.8%(69/165),缩小膜壳绦虫阳性率为19.0%(111/165)。在阳性鼠中同时感染两种膜壳绦虫者有15只,阳性率2.5%(15/165)。各地区…     

横转副裸头绦虫的发育史研究

1980年8—11月在四川阿坝藏族自治州红原县牧区,剖检21只喜玛拉雅旱獭(Marmota himalayana Hodegson),其中7只感染一种副裸头绦虫,共得20个成虫,感染强度1—8个。成虫经形态比较研究后鉴定为横转副裸头绦虫Paranoplocephala transversaria(Krabbe)。本虫的生活史至今尚未阐明。我们用当地采集的地螨感染本虫的孕卵体节,并定期剖检,完成了本虫在其中间宿主体内各期幼虫的发育史,现把研究结果报告如次。     

绦虫类细胞遗传学研究 Ⅰ.缩小膜壳绦虫的染色体组型

缩小膜壳绦虫(Hymenolepis diminuta,长膜壳绦虫)的染色体研究,国外已有报告(Jones,1945;Kisner 1957;Douglas,1962)认为该虫染色体数目为2n=12,但均未作染色体组型分析。国内尚未见报道。本文采用秋水仙素短期体外培养——低渗处理——空气干燥技术,研究了缩小膜壳绦虫的染色体组型,现将结果报告如下:     

白洋淀和太湖地区鸟类绦虫区系的比较研究

本文对白洋淀和太湖地区鸟类绦虫区系进行了比较研究,并对太湖鸟类绦虫区系作了初步分析。结果表明,鸟类绦虫区系分布与宿主区系分布密切相关,亲缘关系相近的宿主有许多相同的或亲缘相近的绦虫,这种现象为研究宿主与寄生虫的演化提供了可靠途径;发现鸟的越冬地绦虫种类比迁徙地种类丰富,分析其原因,除温、湿度、中间宿主等生态条件之外,与鸟的迁徙有一定关系。太湖地区的绦虫具有北方型和随遇型,亦有世界性种类和东半球广布种,提出了两地区家禽和野生鸟类所寄生的共同种类的绦虫。     

山东省微山湖禽类绦虫的调查

1975年11—12月,我们在山东省微山湖地区进行禽类寄生蠕虫调查。共解剖野生鸟类137只,分隶于3目3科7属15种,其中有绦虫寄生的鸟类共103只,占剖检总数的75.1％;所获绦虫标本,经鉴定共有10种,隶于膜壳科(Hymenolepididae)的7属,其中有     

内蒙古呼伦贝尔草原多房棘球蚴病病原的调查

本文报道在内蒙古呼伦贝尔草原主体部分四个牧业旗的草场进行多房棘球蚴病病原调查的结果。发现布氏田鼠(Microtus brandti)及长爪沙鼠(Meriones unguicutatus)是本绦虫的中间宿主、沙狐(Vulpes corsac)是其终末宿主。布氏田鼠是本绦虫中间宿主新记录,长爪沙鼠和沙狐分别是国内本绦虫中间宿主和终宿主新记录。布氏田鼠是呼伦贝尔草原的优势啮齿类,其平均感染率为2.43％(64/2635),越冬成鼠感染率高达5.23％—14.29％(平均6.66％)。长爪沙鼠感染率虽达16.67％(1/6),但鼠数不多。沙狐是本草原常见的食肉兽,检查6只沙狐,其中2只(33.3％)肠内含多房棘球绦虫成虫无数。用其孕节饲喂实验室小白鼠6只,6个月后检查各实验鼠,肝脏均布满泡状多房棘球蚴。呼伦贝尔草原本绦虫成虫及原头节形态特征均与我国西北本虫种差异显著,而与苏联及美国阿拉斯加的多房棘球绦虫西伯利亚亚种比较相似。     

白洋淀鸟类寄生蠕虫的调查研究 Ⅲ.绦虫

关于我国野禽绦虫的调查,过去进行得极少。解放前,仅有曾省(Tseng,1932,1933)对雁形目、鴴形目鸟类绦虫做过报导,共记载绦虫49种,隶于5科21属。徐锡藩(Hsu,1935,1936)对我国各类动物绦虫发表过综合报告,其中记述了野禽绦虫4科17属53种。日本学者杉木正笃(Sugimoto,1939)在我国台湾省进行了经济动物寄生虫调查,著     

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。     

Gastrointestinal helminths of the Mexican duck, Anas platyrhynchos diazi Ridgway, from north central Mexico and southwestern United States

Twenty-five species of helminths, recovered from the gastrointestinal tracts of 129 Mexican ducks from Mexico and the United States, were all new host records. The species included: Echinoparyphium recurvatum, Echinostoma revolutum, Hypoderaeum conoideum, Notocotylus attenuatus, Prosthogonimus cuneatus, Zygocotyle lunata, Anomotaenia ciliata, Cloacotaenia megalops, Diorchis bulbodes, Diorchis sp., Drepanidotaenia lanceolata, Echinocotyle rosseteri, Fimbriaria fasciolaris, Fimbriarioides sp., Hymenolepis sp. 1, Hymenolepis sp. 2, Sobolevicanthus gracilis. Corynosoma constrictum, Polymorphus minutus, Amidostomum acutum, Echinuria sp., Epomidiostomum crami, Hystrichis varispinosus, Rusguniella arctica, and Tetrameres sp. Fimbriarioides sp. occurred predominantly in ducks from south-central Chihuahua, Mexico. The distributions for the other 24 species of the helminths were not significantly different among the four collecting areas. The helminth fauna for the 32 complete specimens and 97 intestinal tracts was distributed relatively evenly among the hosts with a calculated mean evenness of 0.77 +/- 0.15 and 0.89 +/- 0.03 respectively. The parasite fauna was more similar to those of the black duck Anas rubripes Brewster of eastern North America (53%), the mallard, Anas platyrhynchos (L.) (49%), and the mottled duck, Anas fulvigula Ridgway, from Florida (45%), than to the green-winged teal, Anas crecca (L.) (36%), the gadwall, Anas strepera (L.) (30%), and the American wigeon, Anas americana Gmelin (26%), collected in the Southwest.     

Ultrastructure of oncospheral envelopes in Hymenolepidids (Cestoda) with aquatic life cycles

The ultrastructure of the oncospheral envelopes of five species of hymenolepidid cestodes, namely, Fimbriaria fasciolaris, Dicranotaenia coronula, Sobolevicanthus gracilis, Diorchis elisae and Diorchis ovofurcata are described. These cestodes are parasites of aquatic hosts and utilise aquatic invertebrates as intermediate hosts. The ultrastructure of the oncospheral envelopes was essentially similar among these species. However, the structure of the components of the inner oncospheral envelopes displayed significant structural variation among the five species examined. The small eggs of D. coronula and S. gracilis have a thin embryophore and oncospheral membrane. The eggs of these species settle at the bottom of the water body and are eaten by benthic crustaceans. Eggs of F. fasciolaris, D. elisae and D. ovofurcata have thick multilayered embryophores with specific ornamentation. Moreover, in Diorchis species the eggs are elongate, and the oncospheral membrane is thick and striated. Zones of electron-dense aggregates penetrate the polar filaments in these species. Eggs of F. fasciolaris float passively in water whereas those of Diorchis species are attached by long filaments to aquatic plants and are eaten by crustaceans in the littoral zone. The interrelationships among the ultrastructure of the oncospheral envelopes, cestode life cycles and habitat of crustacean intermediate hosts are drawn and discussed.     

The population biology of Hymenolepis tenerrima (Linstow 1882) Fuhrmann 1906 (Cestoda, Hymenolepididae) in its intermediate host Herpetocypris reptans (Ostracoda)

The occurrence of Hymenolepis tenerrima cysticercoids in a population of the intermediate host, Herpetocypris reptans is described for a one year period between October 1980 and September 1981. Parasite occurrence varied seasonally. The prevalence of infection decreased during the winter due to the death of infected hosts and low levels of transmission. Parasite transmission increased during the summer months and the maximum number of cysticercoid stages in the environment occurred in June. Juvenile ostracods were not infected and in adult ostracods a maximum of 3 cysticercoids/host was observed. The presence of H. tenerrima larval stages within the haemocoele had a marked influence upon the survival and fecundity of infected ostracod intermediate hosts.     

Hymenolepis nana: worm recovery from congenitally athymic nude and phenotypically normal rats and mice

When eggs or mouse-derived cysticercoids of Hymenolepis nana were inoculated into previously uninfected congenitally athymic nude (rnu/rnu) rats of an outbred Rowett strain, they failed to mature in the intestinal lumen. They also failed to mature in phenotypically normal (rnu/+) littermates, except when these hosts were treated with cortisone acetate from the beginning of the lumen phase. The Rowett rat, either thymus-deficient or not, was susceptible to tissue cysticercoids but resistant to luminal adults. It is therefore considered to be an unnatural host, at least for mouse-derived H. nana. There was little or no difference in susceptibility to initial tissue cysticercoids between these nude rats and phenotypically normal ones. The normal rats became completely resistant to reinfection with eggs and no secondary cysticercoids developed in their intestinal tissue, whereas the nude rats showed unaltered susceptibility to secondary tissue cysticercoids. Thus, acquired resistance to egg challenge, assessed by the failure of tissue cysticercoid recovery, was thymus-dependent. However, innate resistance to both a primary egg dose, assessed by the low recovery rates of tissue cysticercoids, and to a primary cysticercoid dose, assessed by the failure of luminal adult recovery, were thymus-independent. The effect of cortisone acetate to initiate maturation of H. nana appeared to be unrelated to thymus function. In contrast, all mice, either thymus-deficient or not, were highly susceptible to both phases. The number of worms recovered was more than 10 times greater than that of cysticercoids established in the rat's intestinal tissue.(ABSTRACT TRUNCATED AT 250 WORDS)     

The terminology of larval cestodes or metacestodes

The terminology associated with the nomenclature of larval or metacestodes is reviewed as well as the various morphological and developmental characters used to define different types of larval cestodes. Based on a review of the literature, the key characters differentiating the types of larval cestodes are the presence of a primary lacuna and the invagination/retraction of the scolex. The presence of a cercomer and of a bladder-like enlargement of the larval cestode were considered to be useful secondary characteristics. Using these characters, six basic types of larval cestodes were identified: the procercoid, an alacunate form which cannot develop further until ingested by a second intermediate host; the plerocercus, an alacunate form with a retracted scolex; the plerocercoid, an alacunate form with an everted scolex; the merocercoid, an alacunate form with an invaginated scolex; the cysticercoid, a lacunate form with a retracted scolex; and the cysticercus, a lacunate form with an invaginated scolex. The diversity of larval types within the broad classifications of cysticercoid and cysticercus can be differentiated by the use of appropriate prefixes. Deficiencies in knowledge of specific types of larval cestodes are identified and further avenues of research are indicated.Pseudonym for the contributors of a workshop on metacestode terminology, chaired by I. Beveridge, which took place during the Third International Workshop for Tapeworm Systematics,Sofia, Bulgaria, 20-24 July, 1999 (Organiser: B.B. Georgiev).     

Lumen phase specific cross immunity between Hymenolepis microstoma and H. nana in mice

, and 1988. Lumen phase specific cross immunity between Hymenolepis microstoma and H. nana in mice. International Journal for Parasitology 18: 1019–1027. When mice inoculated with five cysticercoids of Hymenolepis microstoma were challenged with H. nana, they showed strong resistance to challenges with both eggs and cysticercoids of H. nana from day 20. The immunity became complete from day 30 onward: no tissue cysticercoids or lumenal adults of H. nana were established in these mice. However, when mice were challenged with H. nana 10 or 20 days after 10-day old immature H. microstoma were removed by an anthelmintic, the immunity evoked was directed exclusively against the lumenal phase of the cysticercoid challenge but not the tissue cysticercoids of the egg challenge. When mice experienced the prepatent infection with H. microstoma twice, the immunity evoked was also against the lumenal phase of the egg challenge: the oncospheres developed into tissue cysticercoids but thereafter completely failed to develop into lumenal adult tapeworms. Infection with a single cysticercoid of H. microstoma was shown to be sufficient to evoke immunity against H. nana cysticercoid infections in two strains of mice. Sera from mice which experienced a patent infection with H. microstoma revealed that IgG, IgA, IgM isotypes reacted against oncospheres and cysticercoids of both species, while sera from mice which experienced two prepatent infections reacted with cysticercoids only. Sera from H. microstoma infected mice resistant to H. nana caused precipitations on 4-day-old H. nana in vitro. A correlation exists between the presence of stage specific antibodies and resistance to the different stages.     

Failure to infect laboratory rodent hosts with human isolates of Rodentolepis (= Hymenolepis) nana

Confusion exists over the species status and host-specificity of the tapeworm Rodentolepis (= Hymenolepis) nana. It has been described as one species, R. nana, found in both humans and rodents. Others have identified a subspecies; R. nana var. fraterna, describing it as morphologically identical to the human form but only found in rodents. The species present in Australian communities has never been identified with certainty. Fifty one human isolates of Rodentolepis (= Hymenolepis) nana were orally inoculated into Swiss Q, BALB/c, A/J, CBA/ CAH and nude (hypothymic) BALB/c mice, Fischer 344 and Wistar rats and specific pathogen free (SPF) hamsters. Twenty four human isolates of R. nana were cross-tested in flour beetles, Tribolium confusum. No adult worms were obtained from mice, rats or hamsters, even when immunosuppressed with cortisone acetate. Only one of the 24 samples developed to the cysticercoid stage in T. confusum; however, when inoculated into laboratory mice the cysticercoids failed to develop into adult worms. The large sample size used in this study, and the range of techniques employed for extraction and preparation of eggs provide a comprehensive test of the hypothesis that the human strain of R. nana is essentially non-infective to rodents.     

Hymenolepis nana: immunity against oncosphere challenge in mice previously given viable or non-viable oncospheres of H. nana, H. diminuta, H. microstoma and Taenia taeniaeformis

When mice, previously given oral inoculation with viable oncospheres of the heterologous cestode species (Hymenolepis diminuta, H. microstoma, Taenia taeniaeformis) and the homologous one (H. nana), were challenged with oncospheres of H. nana 4 days after the primary inoculation, they showed strong and complete resistance to H. nana challenge, respectively. However, the resistance was not evoked in mice given either infective eggs of Toxocara canis or non-viable oncospheres of all cestode species examined. Congenitally athymic nude mice given viable oncospheres did not show any resistance to H. nana either. Eosinophil infiltration around cysticercoids of H. nana in the intestinal villi appeared to be more prominent in mice previously given viable oncospheres of H. diminuta than in mice given non-viable oncospheres or PBS only. Some of the eosinophils in the villus harboring cysticercoid(s) of H. nana invaded the epithelia in the former, whereas all eosinophils remained in the lamina propria in the latter. There was almost no eosinophil infiltration in nude mice. Microscopic observations revealed that oncospheres of H. diminuta, which require beetles as the intermediate host like H. microstoma, could invade the mouse intestinal tissue. Therefore, it is strongly suggested that the strong cross resistance to H. nana in mice, induced by oncospheres of all heterologous cestode species, is thymus-dependent and due to oncospheral invasion into the intestinal tissue of mice.     

Shape variation of cysticercoids of Hymenolepis diminuta (Cyclophyllidea) from fed, partially fed, and fasted Tribolium confusum (Coleoptera)

Quantitative studies of a crowding effect on cysticercoids of Hymenolepis diminuta in the intermediate host are few and limited in scope. In this study, we developed a technique to rapidly collect morphological information on large numbers of parasites, and verified the utility of geometric models for simple and accurate estimation of cysticercoid size for quantitative studies. These models were tested using measurements from 4,899 H. diminuta obtained from 666 Tribolium confusum exposed 1-4 wk previously. Length, width, and depth of the body and cercomer (when present) can be used in conjunction with these models to provide the most accurate estimation of parasite size. However, parasite body length alone can be used, with adjustment for effects of host diet and infection intensity, to predict the remaining measurements in incomplete specimens. Parasites that developed in higher intensity infections, or in hosts with reduced food intake, were narrower and had a proportionately shorter cercomer. Host age, sex, and mating status, and parasite age also had statistically significant, but small-magnitude, effects on parasite shape.     

Identification of life cycle stages of Cyathocephalus truncatus (Cestoda: spathebothriidea) using molecular techniques

Morphological identification of tapeworm species at larval stages (procercoids and cysticercoids) is often difficult because few diagnostic characters are available. In the present study, a molecular approach (sequencing of partial 18S rDNA gene) was used to evaluate the genetic similarity between adult specimens of Cyathocephalus truncatus (Pallas, 1871) (Cestoda: Spathebothriidea) found in fish, its definitive host, and procercoids of the same species recovered from amphipod, Echinogammarus stammeri (Karaman, 1931). Furthermore, cestode cysticercoids of uncertain species were found in the amphipod's hemocoel. The sequences obtained from adults and procercoids were identical, and even very similar to those of C. truncatus available in GenBank, whereas the sequences obtained from cysticercoids differed significantly from those of adults and procercoids, indicating that these larvae belong to another species; later it was demonstrated that they were cysticercoids of Microsomacanthus pachycephala (Linstow, 1972), a cestode of the Hymenolepididae (Cyclophyllidea). The results of this investigation show that the comparison of nucleotide sequence data may avoid misclassification of developmental stages of parasites, which use the same intermediate host.