Formation and structure of the cyst wall of Stictodora lari (Trematoda: Heterophyidae)

Leong, C. H. D.; Howell, Michael J.

doi:10.1007/bf00260002

Cited by 11 publications

(8 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The secretory activity of the excretory bladder lining of P. squamatus cercariae is obvious as indicated by numerous secretory inclusions, the exact role of which remains obscure. In previous studies, it has been proposed that the secretory products of the cercarial bladder may serve to detoxify metabolic wastes at the metacercarial stage (Krupa et al, 1969) or to participate in metacercarial cyst formation (Leong & Howell, 1971;Malkova & Galaktionov, 1989). However, no firm evidence for these assertions has been presented.…”

Section: Discussionmentioning

confidence: 99%

An ultrastructural study of the cercarial excretory system in Bucephaloides gracilescens and Prosorhynchus squamatus

Podvyaznaya

Галактионов²

2004

J. Helminthol.

View full text Add to dashboard Cite

The ultrastructure of the flame cells, capillaries, collecting tubes, excretory bladder, excretory atrium, caudal vesicle, lateral caudal ducts and excretory pores of cercariae of Bucephaloides gracilescens (Rudolphi, 1819) Hopkins, 1954 and Prosorhynchus squamatus Odhner, 1905 (Digenea: Bucephalidae) is described. Both species are essentially similar except for some details. The terminal parts of the protonephridia have all the structural features that are typical of trematodes. The collecting tubes in the cercarial body are composed of cells that are wrapped around the lumen. The main collecting tubes are joined to the excretory bladder syncytium by septate junctions. Features of P. squamatus excretory bladder epithelium indicate that it is involved in secretory activity, but this is not the case in B. gracilescens. In both species the luminal surface of the excretory bladder epithelium is increased by lamellae, and the basal plasma membrane forms invaginations. In the bladder syncytium of P. squamatus both apical lamellae and basal invaginations are more developed and mitochondria are also more numerous. The excretory atrium is lined by a syncytium with nucleated cytons located in the surrounding parenchyma. The atrium lining is not continuous with the body tegument and possesses specific secretory inclusions and a thick glycocalyx. Septate junctions connect the atrium syncytium to the excretory bladder epithelium at its anterior end and to the syncytial excretory epithelium lining the caudal vesicle and the lateral caudal ducts at its posterior. In the excretory pores the caudal duct syncytium is joined to the tegument by septate desmosomes.

show abstract

Section: Discussionmentioning

confidence: 99%

An ultrastructural study of the cercarial excretory system in Bucephaloides gracilescens and Prosorhynchus squamatus

Podvyaznaya

Галактионов²

2004

J. Helminthol.

View full text Add to dashboard Cite

show abstract

“…Some evidence of selective re-absorption of substances from the fluid within cercarial excretory tubules has been put forward by CARDELL (1962) in Himasthla quissetensis and by GIBSON (1974) in Podocotyle staffordi. The wall of the cercarial excretory vesicle in Cryptocotyle lingua shows ultrastructural characteristics of protein synthesizing cells (KRUPA et ai, 1969) and the metacercarial excretory vesicle in Stictodora lari synthesizes the final parasitic contribution to the cyst wall (LEONG & HOWELL, 1971). The latter workers suggested that the necessary metabolites may enter the excretory vesicle via the collecting ducts, and that the synthesized protein is passed out through the excretory pore.…”

Section: Discussionmentioning

confidence: 97%

The ecsoma in Hemiuridae (Digenea: Hemiuroidea): tegumental structure and function in the mesocercaria and the metacercaria of Lecithochirium furcolabiatum (Jones, 1933) Dawes, 1947

Matthews¹,

Matthews²

1988

J. Helminthol.

View full text Add to dashboard Cite

Ultrastructural, histochemical and autoradiographical techniques have been used to investigate the development and function of the tegument of both somal and ecsomal body regions in the hemiurid Lecithochirum furcolabiatum. The terms mesocercaria and metacercaria are here adopted for those stages in the copepod second and fish third intermediate hosts respectively on the basis of morphology and on analogy with the Strigeidae. Mesocercariae were obtained by experimental infection of the harpacticoid copepod Tigriopus brevicornis with the cystophorous cercariae (syn. Cercaria vaullegeardi), whilst metacercariae were removed from the body cavities of naturally-infected rockpool teleosts including Gobius paganellus and Blennius pholis. Observations on the mesocercaria show the origin of the ecsoma from the distal half of the excretory vesicle, which at 21 days post-infection is capable of eversion through the terminal pore. The nucleated microrugous surface layer of the ecsoma at this stage is modified or replaced in the metacercaria by anucleate syncytial tegument similar to that of the adult organ. The metacercarial stage is also associated with the more advanced development of the somal tegument. The two stages differ in metabolic activity, the somal tegument of only the metacercaria resembling that of the adult in acid phosphatase distribution. In the mesocercaria the ecsomal tegument showed the strongest uptake of 3H-tyrosine; absorption of the latter was not detected in the metacercaria. 3H-glucose uptake was restricted to the intestinal caeca of both stages.

show abstract

“…The spore-crystal complex of some strains (IB-16, GP308, and ME1) caused the release of some metacercariae from the cyst, making them more susceptible to the proteins and environmental conditions. Some proteins [ 36 ] as well as lipids [ 37 ] have been identified within the histochemical structure of the cysts, and they are target molecules for Cyt toxins (membrane lipids [ 38 ] and virulence factors produced by B. thuringiensis such as cysteine protease (trypsin-like) [ 39 ]. Trypsin is commonly used to dissolve the cyst of the metacercariae to perform studies on the histochemistry and developmental biology of trematode [ 40 ].…”

Section: Discussionmentioning

confidence: 99%

Anthelmintic Effect ofBacillus thuringiensisStrains against the Gill Fish TrematodeCentrocestus formosanus

Mendoza-Estrada

Hernández-Velázquez

Arenas-Sosa

et al. 2016

BioMed Research International

View full text Add to dashboard Cite

Parasitic agents, such as helminths, are the most important biotic factors affecting aquaculture, and the fluke Centrocestus formosanus is considered to be highly pathogenic in various fish species. There have been efforts to control this parasite with chemical helminthicides, but these efforts have had unsuccessful results. We evaluated the anthelmintic effect of 37 strains of Bacillus thuringiensis against C. formosanus metacercariae in vitro using two concentrations of total protein, and only six strains produced high mortality. The virulence (CL50) on matacercariae of three strains was obtained: the GP308, GP526, and ME1 strains exhibited a LC50 of 146.2 μg/mL, 289.2 μg/mL, and 1721.9 μg/mL, respectively. Additionally, these six B. thuringiensis strains were evaluated against the cercariae of C. formosanus; the LC50 obtained from the GP526 strain with solubilized protein was 83.8 μg/mL, and it could be considered as an alternative control of the metacercariae and cercariae of this parasite in the productivity systems of ornamental fishes.

show abstract

Formation and structure of the cyst wall of Stictodora lari (Trematoda: Heterophyidae)

Cited by 11 publications

References 20 publications

An ultrastructural study of the cercarial excretory system in Bucephaloides gracilescens and Prosorhynchus squamatus

An ultrastructural study of the cercarial excretory system in Bucephaloides gracilescens and Prosorhynchus squamatus

The ecsoma in Hemiuridae (Digenea: Hemiuroidea): tegumental structure and function in the mesocercaria and the metacercaria of Lecithochirium furcolabiatum (Jones, 1933) Dawes, 1947

Anthelmintic Effect ofBacillus thuringiensisStrains against the Gill Fish TrematodeCentrocestus formosanus

Contact Info

Product

Resources

About