Excystation of the Encysted Metacercariae of Echinostoma trivolvis and Echinostoma caproni in a Trypsin-Bile Salts-Cysteine Medium and Morphometric Analysis of the Excysted Larvae

2008 ◽  
Vol 94 (3) ◽  
pp. 669-671 ◽  
Author(s):  
Tyler M. Saxton ◽  
Bernard Fried ◽  
Robert C. Peoples
Keyword(s):  
Morphometric Analysis ◽  
Bile Salts ◽  
Echinostoma Caproni ◽  
Echinostoma Trivolvis

Effects of copper sulphate on in vitro encystment of the cercariae of Echinostoma caproni

2004 ◽  
Vol 78 (4) ◽  
pp. 371-372 ◽  
Author(s):  
B. Fried ◽  
J.L. Schneck
Keyword(s):  
Emergency Response ◽  
Cyst Wall ◽  
Copper Sulphate ◽  
Bile Salts ◽  
Spring Water ◽  
Echinostoma Caproni ◽  
Parorchis Acanthus ◽  
High Concentrations

AbstractThe effects of various concentrations of copper sulphate were studied on in vitro encystment of Echinostoma caproni in a Locke's–artificial spring water (ASW) (1:1) medium. Cercariae were killed in 10,000 mg l−1 CuSO4 in Locke's–ASW (1:1) within 24 h and extruded cystogenous material to produce an abnormal cyst wall. The ‘emergency response’ of encystment to high concentrations of copper reported for Parorchis acanthus cercariae did not occur in E. caproni. Concentrations of 1000 mg l−1 and 100 mg l−1 CuSO4 in Locke's–ASW (1:1) also killed the cercariae without encystment by 48 h. A concentration of 10 mg l−1 CuSO4 in Locke's–ASW (1:1) allowed for normal in vitro encystment within 48 h and these cysts were capable of excystation in a trypsin–bile salts medium.

Light microscopic observations of Echinostoma caproni metacercariae during in vitro excystation

1995 ◽  
Vol 69 (3) ◽  
pp. 253-257 ◽  
Author(s):  
R.L. Ursone ◽  
B. Fried
Keyword(s):  
Light Microscopy ◽  
Bile Salts ◽  
Extrinsic Factors ◽  
Echinostoma Caproni ◽  
Allopatric Species ◽  
Saline Pretreatment ◽  
Intrinsic And Extrinsic Factors

AbstractLight microscopy was used to study excystation of Echinostoma caproni metacercariae in various media. Optimal excystation was observed in an alkaline trypsin-bile salts medium (TB) at 40 ± 1°C. The percentage of excystation in TB medium declined following either acid pepsin or acid saline pretreatment. Excystation rarely occurred in either trypsin or bile salts alone. Dissolution of the outer cyst occurred in TB medium thus facilitating excystation. Activation of the larva within the inner cyst led to its eventual release through an aperture in the mucoid plug region. Excystation of this species was facilitated by both intrinsic and extrinsic factors. There were considerable differences in excystation events between this species and the related allopatric species, E. trivolvis

Sign in / Sign up

Export Citation Format

Share Document