ABSTRACT
We identified the echinostome metacercariae in Chinese mystery snails, Cipangopaludina chinensis malleata, from Xiengkhuang Province, Lao PDR with morphologies of adult worms recovered. Total 20 snails were examined with artificial digestion method and then the collected metacercariae were orally infected to a mouse and a rat. Adult worms recovered from experimental animals were observed with a light microscope and a SEM. The metacercariae were round, 125×123 μm in average size, with a moderately thick cyst wall, collar spines distributed in the head collar and excretory granules in 2 canals of excretory tube. Adult flukes (3-week-old in a rat) were elongated, ventrally curved and 5.310×1.023 mm in average size. Head collar distinct, bearing 43 collar spines with 5 end group ones on each side. Oral sucker subterminal, prepharynx very short, pharynx well developed, and esophagus relatively short. Cirrus sac well developed, with a saccular seminal vesicle, and ventral sucker very large. Ovary round and on the median line of the body. Testes tandom and elongated. Eggs operculated, elliptical and 90×57 μm in average size. In the SEM observation, the head crown prominent, with 43 collar spines resembled with horns of younger stag. Scale-like tegumental spines were densely distributed on the surface between the head collar and ventral sucker, and their densities were decreased posteriorly. Conclusively, the metacercariae detected in C. chinensis malleata from Lao PDR were identified as those of Echinostoma macrorchis based on the morphological characteristics of adult worms.
Subject(s)
Adult , Animals , Female , Humans , Mice , Rats , Asian People , Crowns , Digestion , Echinostoma , Eggs , Esophagus , Head , Horns , Metacercariae , Methods , Ovary , Ovum , Pharynx , Seminal Vesicles , Snails , Spine , Testis , TrematodaABSTRACT
Objective To study the differences of the phenoloxidase (PO) relative activity among ribbed shelled Oncomelania hupensis, smooth shelled O. hupensis and Cipangopaludina chinensis. Methods The crude PO fluid was extracted from the soft tissue of O. hupensis and C. chinensis by homogenation and centrifugation. The PO activity was detected with catechol as the substrate in the reaction systems. Results The PO relative activities in the ribbed shelled O. hupensis, smooth shelled O. hupensis and C. chinensis were (25.72 ± 2.27), (14.56 ± 1.24) U / mL and (13.72 ± 1.06) U / mL. The PO relative activity in the smooth shelled O. hupensis was higher than that in the ribbed shelled O. hupensis (q = 21.46, P < 0.05) and C. chinensis (q = 12.00, P < 0.05), while the difference between the PO relative activities of the latter two was not statistically significant (q = 1.62, P > 0.05) . Conclusion There is a difference in the relative PO activity between O. hupensis and C. chinensis, which may be related to the living environment of snails.
ABSTRACT
Objective To study the differences of the phenoloxidase (PO) relative activity among ribbed shelled Oncomelania hupensis, smooth shelled O. hupensis and Cipangopaludina chinensis. Methods The crude PO fluid was extracted from the soft tissue of O. hupensis and C. chinensis by homogenation and centrifugation. The PO activity was detected with catechol as the substrate in the reaction systems. Results The PO relative activities in the ribbed shelled O. hupensis, smooth shelled O. hupensis and C. chinensis were (25.72 ± 2.27), (14.56 ± 1.24) U / mL and (13.72 ± 1.06) U / mL. The PO relative activity in the smooth shelled O. hupensis was higher than that in the ribbed shelled O. hupensis (q = 21.46, P < 0.05) and C. chinensis (q = 12.00, P < 0.05), while the difference between the PO relative activities of the latter two was not statistically significant (q = 1.62, P > 0.05) . Conclusion There is a difference in the relative PO activity between O. hupensis and C. chinensis, which may be related to the living environment of snails.
ABSTRACT
A survey was performed to know the infection status of echinostome metacercariae in Cipangopaludina chinensis malleata snails from Korea. Total 75 snails collected in 5 localities, i.e., Imsil-gun, Jeollabuk-do, Hwasun-gun and Shinan-gun (Aphae and Jido), Jeollanam-do, and Jinju-si, Gyeongsangnam-do, were examined for metacercariae by the artificial digestion method. Infection rates of metacercariae were 80.0%, 66.7%, 100%, 60.0%, and 73.3%, and their densities were 39, 32, 183, 19, and 30 per snail infected, respectively. The metacercariae were round, 105–118×105–118 μm in size, with a thin cyst wall, collar spines on the head collar, and excretory granules in 2 canals of excretory tube. Adult flukes were elongated, ventrally curved, and 5,167×939 μm in average size. Head collar distinct, bearing 45 collar spines with 5 end groups on each side. Oral sucker subterminal, pharynx well developed, and esophagus somewhat short. Cirrus sac well developed, with a saccular seminal vesicle, and ventral sucker very large. Ovary elliptical and on the median line of the body. Testes tandem and slightly lobed. Eggs operculated, elliptical, and 90–103×55–60 μm in size. By scanning electron microscopy, the head collar was prominent with 45 collar spines resembling horns of younger stags. Scale-like tegumental spines were densely distributed on the body surface between the head collar and ventral sucker. Conclusively, it has been first confirmed that the life cycle of E. macrorchis is indigenously maintained in Korea, and C. chinensis malleata snails are popularly infected with the metacercariae of this echinostome.