On the Structure and Life-histories of British Fresh-water Larval Trematodes

Parasitology ◽  
1929 ◽  
Vol 21 (1-2) ◽  
pp. 189-219 ◽  
Author(s):  
W. F. Harper
Keyword(s):  
Fresh Water ◽  
Life Histories ◽  
The Other ◽  
Trematode Species ◽  
Intermediate Hosts ◽  
Double Infection ◽  
Activity Duration ◽  
Large Numbers ◽  
Limnaea Stagnalis ◽  
First Time

A large number of fresh-water Invertebrates has been examined and the parasites obtained from them include examples of the commoner groups to be met with in any area surveyed. Six larval Trematodes have been described in detail, and by means of direct animal experiment two of them have been definitely related to known adults. Of these two one is the larva of Notocotylus seineti Fuhr., and is doubtfully Cercaria monostomi v. Linst., while the other is the larva of Echinoparyphium recurvatum v. Linst., and is described here in detail for the first time. The four xiphidiocercariae described are new. Data relating to the activity, duration of free life, and process of encystment of cercariae within the bodies of secondary intermediate hosts is also given.Effect of the parasite on the host. The disruption of the tissues brought about by the presence of sporocysts or rediae in the liver of a mollusc injures the host, and in many cases brings about its death. The gonads also are often attacked and completely destroyed. This latter feature of parasitic castration has been observed by Giard (1888) among certain species of Limnaea, Planorbis and Paludina attacked by sporocysts. Brown (1926) states that the gonads are rarely infected. As regards the encysted stages of cercariae these appear to do very little harm to their hosts even when present in large numbers. These observations are in agreement with those of Lebour (1912) for the sporocyst, rediae, and encysted stages of marine Trematodes.Double infection. I have found no instance of a double infection among the species described. In the literature, several records show the parasitism of two or more species of cercariae, within one and the same host. The occurrence of two species is most commonly met with, and as a rule one is in predominance. Sewell (1922) states that double infection is not common in India. Faust (1917), on the other hand, has found as many as four trematode species within the same host individual (Planorbis trivolis). Hesse (1923) states that “every large Limnaea peregra examined was heavily infected with sporocysts of either of the two species, but it was rare to find both together.” Brown (1926) in the neighbourhood of Birmingham has found three examples of associated xiphidiocercariae and furcocercariae, one example of xiphidiocercariae and echinostome cercariae, and two examples of echinostome cercaria, all from Limnaea stagnalis L.

Larval development of ovine Neostrongylus linearis in four experimentally infected mollusc species

1994 ◽  
Vol 68 (3) ◽  
pp. 207-210 ◽  
Author(s):  
M.Y. Manga-González ◽  
M.P. Morrondo-Pelayo
Keyword(s):  
Post Infection ◽  
The Other ◽  
Snail Species ◽  
Intermediate Hosts ◽  
Cepaea Nemoralis ◽  
In Series ◽  
Mollusc Species ◽  
Higher Temperature ◽  
The One ◽  
First Time

AbstractDevelopment of Neostrongylus linearis larvae was studied in the snail intermediate hosts Oestophora (Oestophora) barbula, Oestophorella buvinieri, Cepaea nemoralis and Helix (Cryptomphalus) aspersa. The molluscs of each species, all adults, were divided into groups of 40 for infection purposes. The infection doses for the first two snail species were 90 and 50 first stage larvae (L1) of N. linearis, respectively. For C. nemoralis two batches were tested: one with 200 L1 kept at 19°C and the other with 250 L1 at a temperature of 21°C. The same was done with Helix (C.) aspersa with 200 L1 at a temperature of 21°C, on the one hand and 300 L1 at 24°C on the other. One or two molluscs of each species were killed in series from the 6th day post-infection (p.i.) until the 44th. Percentage values for total larvae (1, 2 and 3) and L3 were higher with the lower dose for C. nemoralis, whilst the same was true with the higher dose in Helix (C.) aspersa. In both cases, the higher temperature appeared to contribute to cycle acceleration. Using one way analysis of variance, statistically significant differences were detected between the species of molluscs tested concerning percentages of L1 which penetrated, total larvae and L3. According to our results, the decreasing order of susceptibility of these species of molluscs as experimental intermediate hosts of N. linearis is: O. buvinieri, Oestophora (O.) barbula, C. nemoralis and Helix (C.) aspersa. It is the first time that Oestophora (O.) barbula and Oestophorella buvinieri have been named as experimental intermediate hosts of N. linearis.

scholarly journals Some Notes on the Differentiation of closely-allied Schistosomes

Parasitology ◽  
1922 ◽  
Vol 14 (3-4) ◽  
pp. 245-247 ◽  
Author(s):  
F. G. Cawston
Keyword(s):  
Fresh Water ◽  
Schistosoma Haematobium ◽  
The Other ◽  
Double Infection ◽  
Stagnant Water

When fresh-water snails are examined microscopically, specimens are occasionally encountered that are infested with the cercariae of more than one species. Sometimes these cercariae are easily differentiated. A snail may harbour numerous eye-spotted amphistomes and a few distomes without eye-spots, or furcocercous forms may be associated with cercariae possessing undivided tails. In some collections of semi-stagnant water, however, the same individual snail may be found infested with at least two distinct schistosomes. In 1916, I found Physopsis africana (in an overflow pool along the course of the Umsindusi river at Pietermaritzburg) heavily infested with two distinct schistosomes, and it was not uncommon, as Dr E. E. Warren also observed, for the two forms to develop in the same host. One of these cercariae I named Cercaria secobii, the other was probably the cercaria of Schistosoma haematobium. Soparkar (1921 a and b) has moreover noted a double infection of Planorbis exustus near Bombay.

Cercariae Opisthorchis felineus and Metorchis bilis from first intermediate hosts for the first time in basin of Chany lake (Novosibirsk region, Russia) is found

2016 ◽  
Vol 3 (3) ◽  
pp. 421-429 ◽  
Author(s):  
Сербина ◽  
E. Serbina
Keyword(s):  
Human Health ◽  
Western Siberia ◽  
Intermediate Hosts ◽  
Double Infection ◽  
Host Snail ◽  
Opisthorchis Felineus ◽  
Novosibirsk Region ◽  
Lake Systems ◽  
First Time

Objective of research: to perform the analysis of long-term (15 annum) dynamics of Bithyniidae snails infected by trematode parthenites from the Chany Lake, the biggest lake in the south of Western Siberia. Materials and methods: The Bithyniidae snails examined in the lake-river systems Chany Lake in 1994-2013 (in the middle reaches and in the estuary of the Kargat River) and in the Zolotye Rossypi Bay and the Malye Chany Lake. The Bithyniidae snails were collected from May to September (twice in any ten days) by hand from 4–6 plots of 0.25 m2 at a depth of 0.1–0.7 m. In total, 8,316 Bithynia troscheli (Paasch, 1842) and 766 В. tentaculata (L., 1758) were examined. Identification of parthenitae trematode was based on observation when mature cercariae were capable of leaving the shell of the host snail on their own. Results and discussion: In Bithyniidae snails, we found parthenites from trematodes from 12 families Cyathocotylidae Mühling, 1898 Poche, 1925; Prosthоgonimidae Luhe, 1909; Pleurogenetidae Looss, 1898; Lecithodendriidae Odhner, 1911; Microphallidae (Ward, 1901) Travassos, 1920; Plagiorchiidae Lühe, 1901 Echinostomatidae (Looss 1899) Dietz, 1909 Odhner 1910); Psilostomidae (Looss 1900) Odhner 1913; Notocotylidae Luhe, 1909; Monorchiidae Odhner, 1911; Cyclocoelidae Kossack, 1911 и Opisthorchidae (Lass, 1899) Braun, 1901. The prevalence of bithyniid snails infected by trematode parthenites varied from 1,6% to 24,1% in different years The double infection by trematode parthenites was found in 0,96% bithyniid snails from estuary of the Kargat River; 4,45% in the Malye Chany Lake, and 26,6%, in the Zolotye Rossypi Bay. The cercariae of Opisthorchidae family in four annum of the fifteen detected. The prevalence of bithyniid snails infected by trematode parthenites from Opisthorchis felineus (Rivolta, 1884) and Metorchis bilis (Braun, 1890) was observed in Chany Lake systems for the first time. Both species (O. felineus and M. bilis) of trematodes have danger to human health and causes very dangerous disease, opisthorchiasis and metorchiasis.

Resumption of Feeding by and Survival of Adult Sockeye Salmon (Oncorhynchus nerka) Following Advanced Gonad Development

1963 ◽  
Vol 20 (1) ◽  
pp. 95-100 ◽  
Author(s):  
J. R. McBride ◽  
U. H. M. Fagerlund ◽  
M. Smith ◽  
N. Tomlinson
Keyword(s):  
Fresh Water ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Gonad Development ◽  
The Other ◽  
Green Color ◽  
Force Feeding ◽  
In Captivity ◽  
First Time

Adult, migrating, fasting sockeye salmon (Oncorhynchus nerka) were held in captivity in fresh water without spawning well beyond the time when they would normally have done so and died. A few of the fish were then gonadectomized and force feeding was begun. A few unoperated fish were fed similarly while the remainder served as unoperated, unfed controls. The gonads of the operated fish were well developed. After a period of feeding of about four months some fish in each group had survived. The fed fish had regained their green color and much of their weight and vigor, while the surviving unfed fish were extremely emaciated and listless. At this time voluntary feeding by the force-fed fish was observed for the first time, and it was then found that the five surviving unfed controls would also take food voluntarily. While two of these fish died without apparent improvement in their condition, the other three gradually regained green color, weight and vigor.

Extra-mammalian larval stages of Elaphostrongylus alces (Nematoda: Protostrongylidae), a parasite of moose (Alces alces) in Fennoscandia

1998 ◽  
Vol 76 (1) ◽  
pp. 33-38 ◽  
Author(s):  
Murray W Lankester ◽  
Ing-Marie C Olsson ◽  
Margareta Stéen ◽  
Alvin A Gajadhar
Keyword(s):  
Long Range ◽  
Alces Alces ◽  
The Other ◽  
Intermediate Hosts ◽  
Larval Stages ◽  
Third Stage ◽  
The Mean ◽  
First Time

Dimensions and illustrations of the first-, second-, and third-stage larvae of Elaphostrongylus alces are presented for the first time. First-stage larvae were 417 ± 16 µm long (mean ± SD) (range 377-445 µm) and similar in size to those of E. cervi (420 ± 13 µm long; range 392-445 µm) and E. rangiferi, the other recognized members of the genus. The mean length of third-stage E. alces larvae (714 ± 23 µm long; range 675-756 µm) recovered from gastropod intermediate hosts was significantly less than that of E. cervi (831 ± 78 µm long; range 669-954 µm) and E. rangiferi, providing further evidence of the distinct status of E. alces, a recently described species from moose in Fennoscandia.

scholarly journals MORTALITY OF FISH FRY AS A RESULT OF SPECIFIC AND ASPECIFIC CERCARIAL INVASION UNDER EXPERIMENTAL CONDITIONS

1999 ◽  
Vol 47 (4) ◽  
pp. 433-450 ◽  
Author(s):  
G. Majoros
Keyword(s):  
Intermediate Host ◽  
Common Carp ◽  
Intestinal Wall ◽  
The Body ◽  
The Other ◽  
Fish Mortality ◽  
Fish Ponds ◽  
Intermediate Hosts ◽  
Experimental Conditions ◽  
Large Numbers

Although the effect exerted on fish by fluke cercariae developing in fish as intermediate hosts is fairly well known, cercariae of flukes requiring intermediate hosts other than fish occur in fish ponds in much higher numbers. To study the effect of these latter cercariae on fish fry, a few days old common carp fry (Cyprinus carpio) were exposed to cohorts of xiphidiocercariae or echinocercariae shed by one or two snails acting as intermediate hosts. The observed pathogenicity of these cercariae was compared to the well-known pathogenic effect ofDiplostomumcercariae. AlthoughDiplostomumcercariae proved to be the most pathogenic, occasionally also the other two types of cercariae could kill the common carp fry by invading their body. Xiphidiocercariae ingested by the fish penetrated the intestinal wall and developed into metacercariae within the body of the fry. They could also get into the musculature through the skin. The much larger echinocercariae invaded the gill cavity where they became encapsulated, thus hampering gill function and leading to fish mortality due to oxygen deficiency.Diplostomumcercariae were more pathogenic than the cercariae of the other two flukes in that they were shed by the intermediate host in very large numbers. Although much less xiphidiocercariae and echinocercariae emerged from the intermediate host snails thanDiplostomumcercariae, the former could kill the fish fry already in lower numbers. These findings prove that fluke cercariae nonspecific to fish may exert pathogenic effects on fish, and presumably contribute to the early mortality of young fry placed out into fish ponds.

scholarly journals A List of the Caddisflies (Insecta: Trichoptera) from Kyrgyzstan, with a New Record (Triaenodes reuteri McLachlan 1880)

Zootaxa ◽  
2020 ◽  
Vol 4896 (1) ◽  
pp. 113-122
Author(s):  
İBRAHÝM KÜÇÜKBASMACI ◽  
SAVAŞ CANBULAT
Keyword(s):  
New Species ◽  
Fresh Water ◽  
Male Genitalia ◽  
New Record ◽  
Water Distribution ◽  
Literature Search ◽  
New Records ◽  
Relevant Literature ◽  
The Other ◽  
First Time

The Trichoptera include more species than any of the other primarily aquatic orders of insects, which are usually found in clean fresh water. Distribution of the species of an order based on geography can provide guidance for researchers working in the field. In the current study, for the first time, a list of known Trichoptera species in Kyrgyzstan is given along with a new record. The list is prepared based on the relevant literature between 1875 and 2020 and a study conducted in 2012. Literature search revealed that 21 known species of caddisflies of 13 genera and 8 families have been reported from Kyrgyzstan; our research found that Triaenodes reuteri McLachlan 1880 is also present in Kyrgyzstan. We also re-illustrate the male genitalia of T. reuteri and provide a detailed redescription. Based on literature search and our observations, the Kyrgyzstan caddisfly fauna has been poorly studied; it is expected that new records and new species will be found in Kyrgyzstan through further research. 

scholarly journals Digenean larvae parasitizing Ruditapes decussatus (Bivalvia) from Tunisianan coasts

2015 ◽  
Vol 52 (2) ◽  
pp. 104-112 ◽  
Author(s):  
E. Dhrif ◽  
R. Antar ◽  
S. Abidli ◽  
L. Gargouri
Keyword(s):  
Biological Indicators ◽  
The Other ◽  
Trematode Species ◽  
Ruditapes Decussatus ◽  
Monthly Variation ◽  
First Time ◽  
Eleven Species

Summary Eleven species of trematode larvae (sporocysts and cercariae of Bucephalus labracis Paggi et Orecchia, 1965 and Cercaria lata Lespes, 1857 and metacercariae of Acanthoparyphium sp. Dietz , 1909, Caecincola parvulus Marshall et Gilbert, 1905, Curtuteria australis Allison, 1979, Gymnophallus fossarum Bartoli, 1965, Gymnophallus rebecqui Bartoli, 1983, Lepocreadium pegorchis Stossich, 1901, Parazoogonus sp. Looss, 1901, Psilostomum brevicolle Creplin, 1829 and Robphildollfusium fractum Rudolphi, 1819) were found in the clam (Ruditapes decussatus) from Tunisian coasts. A part from B. labracis and Cercaria lata, the other trematode species were recorded for the first time in Tunisia. The examination of the frequency of recorded parasites reveals some monthly variation. This variation is statistically significant by comparing the sampling sites. These results indicate that more frequent parasites (G. fossarum, Cercaria lata, Curtuteria australis and Acanthoparyphium sp.) could be considered as biological indicators making it possible to predict the capture localities of the clams.

On the Structure and Life Histories of British Fresh-water Furcocercariae

Parasitology ◽  
1931 ◽  
Vol 23 (3) ◽  
pp. 310-324 ◽  
Author(s):  
W. F. Harper
Keyword(s):  
Life Cycle ◽  
Fresh Water ◽  
Liver Tissue ◽  
Life Histories ◽  
Animal Experiment ◽  
Helminth Infection ◽  
Detailed Account ◽  
Double Infection ◽  
Parasitic Castration ◽  
Feeding Experiments

Three species of furcocercariae are described. By means of direct animal experiment with secondary, intermediate and final hosts I have shown that one species develops into Tetracotyle typica Dies., the larva of Strigea tarda Steenstrup, and a connected detailed account of this life cycle is here given. Of the two other species, both of which are new, I have been able to trace the development of one into Tetracotyle n.sp. in Planorbis crista L., and P. albus Müll. Feeding experiments with this new Tetracotyle using ducklings as final hosts failed, however, to produce the corresponding adult.Effect of the parasite on the host. The usual results of helminth infection of this nature are observable, namely, marked disruption of liver tissue and in many cases complete parasitic castration of the molluscs infected.Double infection. In the course of my investigations on larval Trematodes I have met with one example of double infection with sporocysts, viz. Cercaria F.1 and F.2, within one and the same individual of Planorbis albus Müll. This condition was found only on one occasion, Cercaria F.1 being in predominance. Instances of double infection have been recorded by Faust (1971) and Sewell (1922), and from this country by Hesse (1923) and Brown (1926). The condition, however does not appear to be a common one.

scholarly journals On the Helminth Fauna of the Muskrat (Ondatra zibethicus (Linnaeus, 1766)) in the Barnim District of Brandenburg State/Germany

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2444
Author(s):  
Rolf K. Schuster ◽  
Peter Specht ◽  
Siegfried Rieger
Keyword(s):  
Flood Control ◽  
Age Groups ◽  
The Other ◽  
Intermediate Hosts ◽  
Opisthorchis Felineus ◽  
Larval Stages ◽  
Burrowing Activity ◽  
Fur Animals ◽  
First Time ◽  
Plagiorchis Elegans

The muskrat is a neozoon species that has occupied many countries of continental North Europe after its introduction from north America as fur animals. Due to its burrowing activity it damages river and canal banks and structures of flood control. For this reason, the eradication of this alien species is recommended. Muskrats are also of parasitological interest since they can act as suitable intermediate hosts for Echinococcus multilocularis. On the other hand, little is known on the other helminths that infect muskrats. A total of 130 muskrats of different age groups trapped in different habitats in the Barnim district of the Brandenburg state by a professional hunter were examined for parasites and seven trematodes (Echinostoma sp., Notocotylus noyeri, Plagiorchis elegans, Plagiorchis arvicolae, Psilosostoma simillimum, P. spiculigerum, Opisthorchis felineus and four larval cestode species (Hydatigera taeniaeformis, Taenia martis, Taenia polyacantha, Taenia crassiceps) were detected. Larval stages of E. multilocularis were not found. O. felineus was found for the first time in muskrats in Germany. All the named parasites were present in Europe prior to the introduction of muskrats. With a prevalence of 48.9%, Strobilocercus fasciolaris, the larval stage of the cat tapeworm, H. taeniaeformis, was the most frequent parasite found in adult muskrats.

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