Distribution of the cestode Urocystis prolifer Villot, 1880 (Cyclophyllidea: Hymenolepididae) in the Palaearctic and new data on its postembryonic development

2021 ◽  
Vol 95 ◽  
Author(s):  
S.A. Kornienko ◽  
L.A. Ishigenova
Keyword(s):  
Host Specificity ◽  
Geographical Distribution ◽  
Experimental Infection ◽  
Definitive Host ◽  
Intestinal Parasite ◽  
Geographic Area ◽  
Postembryonic Development ◽  
Generic Diagnosis ◽  
Intermediate Hosts ◽  
Very High

Abstract Urocystis prolifer Villot, 1880 is an intestinal parasite of Sorex spp. In the Palaearctic. There are significant differences in the descriptions of both adults and stages of ontogenesis of U. prolifer as described by various authors. The experimental infection of intermediate hosts with cestodes has been conducted. An overview of the geographical distribution, infestation of the definitive hosts and the development of the metacestode stages of U. prolifer are presented. The cestode is characterized by an extensive geographic area in the Palaearctic, wide host specificity and very high rates of infection of its definitive host. Urocystis prolifer has been recorded mostly in the taiga and forest zones of Palaearctic. Fourteen species of Sorex were registered as the definitive host. Redescription of U. prolifer and an amended generic diagnosis are provided. A complete description of the ontogeny from oncosphere to fully developed metacestode is given. Features of development of the metacestode are an asexual larval reproduction, the absence of the anterior and posterior obturator valve in the cyst of the fully developed urocyst, as well as excretory bodies.

scholarly journals Sarcocystis Attenuati N. Sp. (Apicomplexa: Sarcocystidae) Infecting the Asian Gray Shrew, Crocidura Attenuata (Insectivora: Soricidae), in China

2021 ◽  
Author(s):  
junjie hu ◽  
Jun Sun ◽  
Yanmei Guo ◽  
Hongxia Zeng ◽  
Yunzhi Zhang ◽  
...  
Keyword(s):  
Host Specificity ◽  
Definitive Host ◽  
18S Rdna ◽  
Common Species ◽  
Molecular Characteristics ◽  
Intermediate Hosts ◽  
Parasite Life Cycle ◽  
Rdna Sequences ◽  
Transmission Electron ◽  
18S Rdna Sequences

Abstract Background: There are limited data on Sarcocystis in insectivores. The Asian gray shrew, Crocidura attenuata, is one of the most common species of insectivores in the family Soricidae distributed in South Asia and Southeast Asia. To date, Sarcocystis has never been recorded in this host.Methods: Tissues from 42 Asian gray shrews were collected in China in 2017 and 2018. Sarcocysts were observed using light (LM) and transmission electron microscopy (TEM). To complete the parasite life cycle, muscle tissues of the host infected with sarcocysts were force-fed to two beauty rat snakes, Elaphe taeniura. Individual sarcocysts from different Asian gray shrews and oocysts/sporocysts isolated from the small intestines and feces of the experimental snakes were selected for DNA extraction, and seven genetic markers, including two nuclear loci (18S rDNA and ITS1), three mitochondrial genes (cox1, cox3 and cytb), and two apicoplastic genes (rpoB and clpC), were amplified, sequenced and analyzed.Results: Sarcocysts were found in 17 of 42 (40.5%) Asian gray shrews. Under LM, the microscopic sarcocysts were exhibited saw-tooth-like protrusions measuring 3.3–4.5 μm. Ultrastructurally, the sarcocyst wall contained numerous lancet- or leaf-like villous protrusions, similar to type 9h. The experimental beauty rat snakes shed oocysts/sporcysts measuring 11.9–16.7 × 9.2–10.6 μm with a prepatent period of 10 to 11 days. Comparing these sequences with those previously deposited in GenBank revealed that the 18S rDNA sequences and cox1 sequences shared the highest similarity with those of S. scandentiborneensis recorded in tree shrews, Tuaia minor and T. tana (i.e., 97.6–98.3% and 100% identity, respectively). Phylogenetic analysis based on 18S rDNA, ITS1 or cox1 sequences revealed that this parasite formed an independent clade with Sarcocystis spp. that utilize small animals as intermediate hosts and snakes as the known or presumed definitive host. On the basis of morphological and molecular characteristics and host specificity, the parasite was proposed as a new species, named S. attenuati.Conclusions: Sarcocysts were recorded in Asian gray shrews for the first time. The sarcocysts were characterized morphologically and molecularly. The 18S rDNA and cox1 sequences of S. attenuati, named in the present study, shared the highest identities with those of S. scandentiborneensis. However, the sarcocysts of the two species of Sarcocystis were quite different under LM and TEM. Based on experimental infection, beauty rat snakes have been proven to be a definitive host of S. attenuati. As more species of Sarcocystis from insectivores and other small mammals are properly morphologically and molecularly characterized, we may gain a better understanding of the biodiversity, host specificity and evolution of Sarcocystis in the future.

scholarly journals LARVAL STAGES OF PHYLLODISTOMUM SP. (DIGENEA, GORGODERIDAE) FROM THE DUCK MUSSELS ANODONTA ANATINA IN UKRAINE

2013 ◽  
Vol 47 (6) ◽  
pp. 37-42 ◽  
Author(s):  
O. S. Kudlai ◽  
L. N. Yanovich
Keyword(s):  
Life Cycle ◽  
Ventral Sucker ◽  
Experimental Infection ◽  
Definitive Host ◽  
Morphological Features ◽  
Carassius Carassius ◽  
Body Proportions ◽  
Intermediate Hosts ◽  
Free Swimming ◽  
Larval Stages

Abstract Rhopalocercous cercariae were found in the gonads of duck mussels, Anodonta anatina (Linnaeus, 1758) collected from the Sluch River (Zhytomyr oblast, Ukraine). The morphological features observed led to conclusion that this species belonged to the genus Phyllodistomum Braun, 1899. Obtained results suggested that the second intermediate hosts in the life cycle of this trematode were absent. Free-swimming cercariae were observed encysting in water. This species is similar to Phyllodistomum pseudofolium Nybelin, 1926 by overall body proportions and ratio of suckers: lengths of oral to ventral sucker 1 : 1.1; widths of the same organs 1 : 1.2. To confirm the taxonomic position of the species found and establish a possible relationship between it and P. pseudofolium an experimental infection of fish Carassius carassius (Linnaeus, 1758) as potential definitive host was performed. The infection was not successful. Descriptions and figures of all detected larval stages of Phyllodistomum sp. are provided.

Taeniasis in a German Shepherd Pup: A Case Report

2019 ◽  
Vol 15 (01) ◽  
pp. 83-84
Author(s):  
B J Thakre ◽  
Joice P Joseph ◽  
Binod Kumar ◽  
Nilima Brahmbhatt ◽  
Krishna Gamit
Keyword(s):  
Case Report ◽  
Life Cycle ◽  
Definitive Host ◽  
Gastrointestinal Diseases ◽  
Intermediate Hosts ◽  
German Shepherd ◽  
Taenia Hydatigena ◽  
Taenia Multiceps ◽  
Taenia Crassiceps ◽  
Dipylidium Caninum

Taenia spp. are long, segmented, parasitic tapeworms and are relatively uncommon in canine gastrointestinal diseases compared to other tapeworms like Dipylidium caninum. These parasites have an indirect life cycle, cycling between definitive and intermediate hosts. Dogs act as definitive hosts of different species of Taenia including Taenia multiceps, Taenia serialis, Taenia crassiceps, Taenia hydatigena, Taenia pisiformis, etc. Taenia multiceps is of greatest zoonotic relevance in human. In the definitive host, it causes only mild infection. Larvae are more likely to cause disease than adult tapeworms. Taeniasis in pets should be cautiously handled because of its zoonotic importance. This communication reports a case of 3 months old pup suffering from Taenia infection that was successfully managed with a combination of praziquantel and fenbendazole.

scholarly journals Effects of parasites upon non-host predator avoidance behaviour in native and invasive gammarids

Parasitology ◽  
2020 ◽  
pp. 1-7
Author(s):  
Sajad Farahani ◽  
Per J. Palsbøll ◽  
Ido Pen ◽  
Jan Komdeur
Keyword(s):  
Invasive Species ◽  
Definitive Host ◽  
Predator Avoidance ◽  
Gasterosteus Aculeatus ◽  
Chemical Cues ◽  
Critical Role ◽  
Fundamental Question ◽  
Intermediate Hosts ◽  
Gammarus Fossarum ◽  
Acanthocephalan Parasite

Abstract The acanthocephalan parasite, Polymorphus minutus, manipulates its intermediate hosts' (gammarids) behaviour, presumably to facilitate its transmission to the definitive hosts. A fundamental question is whether this capability has evolved to target gammarids in general, or specifically sympatric gammarids. We assessed the responses to chemical cues from a non-host predator (the three-spined sticklebacks Gasterosteus aculeatus) in infected and non-infected gammarids; two native (Gammarus pulex and Gammarus fossarum), and one invasive (Echinogammarus berilloni) species, all sampled in the Paderborn Plateau (Germany). The level of predator avoidance was assessed by subjecting gammarids to choice experiments with the presence or absence of predator chemical cues. We did not detect any behavioural differences between uninfected and infected G. pulex and E. berilloni, but an elevated degree of predator avoidance in infected G. fossarum. Avoiding non-host predators may ultimately increase the probability of P. minutus' of predation by the definitive host. Our results suggested that P. minutus' ability to alter the host's behaviour may have evolved to specifically target sympatric gammarid host species. Uninfected gammarids did not appear to avoid the non-host predator chemical cues. Overall the results also opened the possibility that parasites may play a critical role in the success or failure of invasive species.

scholarly journals Global warming and temperature-mediated increases in cercarial emergence in trematode parasites

Parasitology ◽  
2005 ◽  
Vol 132 (1) ◽  
pp. 143-151 ◽  
Author(s):  
R. POULIN
Keyword(s):  
Global Warming ◽  
Geographical Distribution ◽  
Climate Models ◽  
Extreme Values ◽  
Geometric Mean ◽  
Effect Of Temperature ◽  
Trematode Species ◽  
Intermediate Hosts ◽  
Cercarial Production ◽  
Trematode Parasites

Global warming can affect the world's biota and the functioning of ecosystems in many indirect ways. Recent evidence indicates that climate change can alter the geographical distribution of parasitic diseases, with potentially drastic consequences for their hosts. It is also possible that warmer conditions could promote the transmission of parasites and raise their local abundance. Here I have compiled experimental data on the effect of temperature on the emergence of infective stages (cercariae) of trematode parasites from their snail intermediate hosts. Temperature-mediated changes in cercarial output varied widely among trematode species, from small reductions to 200-fold increases in response to a 10 °C rise in temperature, with a geometric mean suggesting an almost 8-fold increase. Overall, the observed temperature-mediated increases in cercarial output are much more substantial than those expected from basic physiological processes, for which 2- to 3-fold increases are normally seen. Some of the most extreme increases in cercarial output may be artefacts of the methods used in the original studies; however, exclusion of these extreme values has little impact on the preceding conclusion. Across both species values and phylogenetically independent contrasts, neither the magnitude of the initial cercarial output nor the shell size of the snail host correlated with the relative increase in cercarial production mediated by rising temperature. In contrast, the latitude from which the snail-trematode association originated correlated negatively with temperature-mediated increases in cercarial production: within the 20 ° to 55 ° latitude range, trematodes from lower latitudes showed more pronounced temperature-driven increases in cercarial output than those from higher latitudes. These results suggest that the small increases in air and water temperature forecast by many climate models will not only influence the geographical distribution of some diseases, but may also promote the proliferation of their infective stages in many ecosystems.

Costs of intraspecific and interspecific host sharing in acanthocephalan cystacanths

Parasitology ◽  
2001 ◽  
Vol 122 (4) ◽  
pp. 483-489 ◽  
Author(s):  
B. S. DEZFULI ◽  
L. GIARI ◽  
R. POULIN
Keyword(s):  
Intermediate Host ◽  
Definitive Host ◽  
Interspecific Interactions ◽  
Sympatric Species ◽  
Competitive Interactions ◽  
Host Size ◽  
Intermediate Hosts ◽  
Transmission Success ◽  
Additional Costs ◽  
Net Benefits

Larval helminths often share individual intermediate hosts with other larval worms of the same or different species. In the case of immature acanthocephalans capable of altering the phenotype of their intermediate hosts, the benefits or costs of host sharing can be evaluated in terms of increased or decreased probability of transmission to a suitable definitive host. Competitive interactions among the immature stages of acanthocephalans within the intermediate host could create additional costs of host sharing, however. The effects of intraspecific and interspecific interactions were measured in 3 sympatric species of acanthocephalans exploiting a population of the amphipod Echinogammarus stammeri in the River Brenta, Italy. The strength of interactions was assessed from differences in the size achieved by infective cystacanths in the intermediate host. The size of Pomphorhynchus laevis cystacanths was not correlated with host size, whereas the size of Acanthocephalus clavula and Polymorphus minutus cystacanths increased with host size. Reductions in cystacanth size caused by intraspecific competition were only detected in P. laevis, but may also occur in both A. clavula and P. minutus. When co-occurring in the same amphipod with cystacanths of A. clavula, cystacanths of P. laevis attained a smaller size than when they occurred on their own. This effect was not reciprocal, with the size of A. clavula cystacanths not being affected. This supports earlier suggestions that it is adaptive for A. clavula to associate with P. laevis in amphipod intermediate hosts, with both species going to the same fish definitive hosts. In contrast, cystacanths of P. laevis achieved their largest size when they co-occurred in an amphipod with a cystacanth of P. minutus, which has a different definitive host (i.e. birds). These findings suggest that the net benefits of sharing an intermediate host can only be estimated by taking into account both the effects on transmission success and the consequences for cystacanth development.

Uromyces dianthi. [Descriptions of Fungi and Bacteria].

1968 ◽  
Author(s):  
E. Punithalingam
Keyword(s):  
Geographical Distribution ◽  
Ivory Coast ◽  
Intermediate Hosts

Abstract A description is provided for Uromyces dianthi. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Pycnia and aecia on Euphorbia, uredia and telia on Dianthus, Arenaria, Bufonia, Gypsophila, Lycnis, Saponaria, Tunica, Saxifraga and Silene. DISEASE: Carnation rust. On leaves and stems of carnation and other members of the Caryophyllaceae. It occurs on cultivated carnation all the year round, causing much injury. The aecidial host is deformed by the rust and affected plants often do not flower. GEOGRAPHICAL DISTRIBUTION: Africa (Ivory Coast, Ghana, Guinea); Asia (Ceylon, India, Japan, Pakistan). (Herb. IMI & Literature.) TRANSMISSION: Not known. The rust has not been known to survive the summer in Delhi (India) and the mode of perennation is uncertain (40: 10). Stored at 5°C the urediospores remained viable for 4 months. It has been suggested that in India the rust could survive the summer in the lower hills either on regular crops or on intermediate hosts such as C. medicaginea, reported to be a perennial in the hills (Joshi, 1960).

scholarly journals Experimental infection with Schistosoma mansoni of Biomphalaria straminea from different parts of the Northeast of Brazil

1986 ◽  
Vol 28 (3) ◽  
pp. 160-165 ◽  
Author(s):  
E. A. Malek ◽  
M. Z. Rouquayrol
Keyword(s):  
Schistosoma Mansoni ◽  
Puerto Rican ◽  
Experimental Infection ◽  
Snail Host ◽  
The State ◽  
Infection Rates ◽  
Biomphalaria Straminea ◽  
Albino Strain ◽  
Very High ◽  
Different Parts

In the western part of the State of Bahia Biomphalaria straminea and B. glabrata both occur, but in the majority of cases they do not share the same habitat. In the State of Ceará, however, B. straminea is the sole snail host of Schistosoma mansoni. In this survey, no naturally infected B. straminea was found among snails collected from Bahia and Ceará, evidently because of the very low infection rates. The susceptibility of laboratory-reared specimens to infection with a Puerto Rican strain of S. mansoni was then tested experimentally. In general, the snails showed very low susceptibility. The infection rates were 1.1% among snails from Redenção (Ceará); 2.3% in those from Pentecoste (Ceará); 2.9% in snails from São Desidério (Bahia), while they were very high among an albino strain (NIH) of B. glabrata used as control. Another group of B. straminea from São Desidério was exposed to a Bahian strain of S. mansoni and the infection rate was still very low (3.6%) Apparently, the very low susceptibility of B. straminea, despite high snail density, is correlated with moderate infection rates with S. mansoni among humans, as shown by the results of stool examinations conducted by SUCAM in the municipalities of Redenção and Pentecoste, in Ceará.

The influence of second intermediate host species on the infectivity of metacercarial cysts of Echinoparyphium recurvatum

1999 ◽  
Vol 73 (2) ◽  
pp. 143-145 ◽  
Author(s):  
A.M. McCarthy
Keyword(s):  
Intermediate Host ◽  
Definitive Host ◽  
Host Species ◽  
Post Infection ◽  
Rana Temporaria ◽  
Biomphalaria Glabrata ◽  
Reproductive Status ◽  
Intermediate Hosts ◽  
Potential Influence ◽  
Second Intermediate Host

The potential influence of second intermediate host species on the infectivity of metacercarial cysts of Echinoparyphium recurvatum to the definitive host Anas platyrhynchos was examined experimentally. Echinoparyphium recurvatum metacercarial cysts were obtained from the following experimentally infected second intermediate hosts 14 days post expsoure to cercariae: Lymnaea peregra; Physa fontinalis; L. stagnalis;Planorbis planorbis; Biomphalaria glabrata; tadpoles of the amphibian Rana temporaria. Metacercarial cysts from each of these hosts were fed, in doses of 50 cysts per individual, to separate groups composed of between four and eight, 3-day-old A. platyrhynchos ducklings. All A. platyrhynchos were necropsied 15 days post-infection and the number, size, and reproductive status of E. recurvatum worms in the intestine was recorded. Analyses of variance on the number (transformed log (x + 1)) and size of worms revealed no significant differences in worms originating from metacercariae formed in the different second intermediate hosts (worm number P > 0.05, and worm size P > 0.05). All worms recovered were found to be gravid. It is therefore concluded that the species of second intermediate host utilized does not influence the infectivity of the metacercarial cyst of E. recurvatum, nor the subsequent establishment and reproductive status of the parasite in A. platyrhynchos.

Geographical Distribution of Schistosomes and their Intermediate Hosts

2015 ◽  
pp. 32-249 ◽  
Author(s):  
W. H. Wright ◽  
N. Ayad ◽  
J. Fraga de Azevedo ◽  
F. S. Barbosa ◽  
V. de V. Clarke ◽  
...  
Keyword(s):  
Geographical Distribution ◽  
Intermediate Hosts
Sign in / Sign up

Export Citation Format

Share Document