The life cycle of Paramphistomum microbothrium Fischoeder, 1901 (Trematoda, Paramphistomidae)

Abstract

The whole life cycle of Paramphistomum microbothrium Fischoeder, 1901, found in cattle of Kenya, East Africa, has been established experimentally.In laboratory conditions, the eggs hatched miracidia on the 14th to 16th day, if they were kept in water at a temperature of 26–28° C.In a snail, Bulinus alluaudi (Dautzenberg), kept at the temperature of 18–20° C., the miracidium developed into a sporocyst, the elongated body of which, containing young rediae, reached a length of 3·6 mm. in about 2 weeks.The first rediae which emerged from a sporocyst were observed on the 14th day, and on the 20th day the first generation rediae began to produce second-generation rediae. From the 28th day onward the first-generation parent rediae ceased to produce daughter rediae and began to develop cercariae only. This period of production of cercariae by the redia lasted about 30 days, and when the life of the first-generation rediae drew to its close, the old rediae developed a few daughter rediae again.Cercariae began to emerge from the first-generation rediae 30 days after exposure of the snail to miracidia. The cercariae left the parent redia in a very immature state and further development occurred in the liver of the snail. The emergence of cercariae from the infected snail began on the 43rd day after exposure to miracidia. Shortly after emerging from the snail, the cercariae attached themselves to vegetation and encysted.Development of rediae of the second, third, fourth and apparently more successive generations followed an identical course to that outlined for the rediae of the first generation. As a result the successive generations of rediae maintain the infection going in an intermediate host and the infected snails were continually shedding cercariae as long as they lived. In the laboratory experiments the life span of some of the infected snails exceeded a year.In cattle infected experimentally P. microbothrium reached maturity and began passing out the eggs about a 100 days after the encysted cercariae were fed to the animals.

A molecular approach for identification of paramphistomes from Africa and Asia

“…This confirmed B. forskalii as a snail host of C. microbothrium and supports the reported geographical distribution of this parasite, which is widely distributed in Africa (including Egypt, Kenya and Tanzania), parts of southern Europe, and southwestern Asia in a wide range of ruminant hosts (Sey, 2000). C. microbothrium has been reported from B. liratus Tristram, 1863(Prod'hon et al, 1968, B. mariei Crosse, 1879 (Gretillat, 1958), B. tropicus Krauss, 1848(Dinnik and Dinnik, 1954Swart and Reinecke, 1962;Dinnik, 1965;Graber and Daynes, 1974), B. truncatus Audouin, 1827 (Looss, 1896(Looss, , 1902Lengy, 1960;Arfaa, 1962), B. forskalii (Looss, 1896(Looss, , 1902, B. natalensis Küster, 1841 (Graber and Daynes, 1974), B. octoploidus Burch, 1972(Graber and Daynes, 1974, Physopsis globosus Morelet, 1866 (Dinnik, 1965) and P. nasutus Martens, 1879 (Dinnik, 1964b(Dinnik, , 1965. Table 1 for description of the samples).…”

“…It is possible that C. microbothrium or other paramphistomes play the same role in increasing the susceptibility of some planorbid snails to other species of Schistosoma Weinland, 1858 including S. haematobium (Bilharz, 1852) Weinland, 1858 and S. mansoni Sambon, 1907, both significant human parasites. Infection of Biomphalaria pfeifferi Krauss, 1848, an important snail host of S. mansoni, with Paramphistomum sukari Dinnik, 1954was reported (Dinnik and Dinnik, 1954, 1957Dinnik, 1965;Graber and Daynes, 1974). Our finding of a paramphistome infection {P4} in Biomphalaria sudanica Martens, 1870, another important snail host of S. mansoni in Africa, is of interest in this regard.…”

Epidemiological studies of amphistome infections in cattle in the highveld and lowveld communal grazing areas of Zimbabwe

“…The epidemiology and seasonal pattern of infection depends on the species of definitive and intermediate host (Rolfe, Boray, Nichols & Collins 1991), the system of management and grazing habits of the cattle (Horak 1967;Boray 1969), the biological potential of the snail hosts (Swart & Reinecke 1962a, b;Dinnik 1964;Horak 1971), the potential of the flukes to infect intermediate and definitive hosts (Dinnik & Dinnik 1954;Dinnik 1964;Horak 1967), the topography of the snail habitats and the climate (Rolfe et al 1991).…”

Cycle biologique de Paramphistomum togolense n. sp. (Trematoda, Paramphistomidae)

“…T.-L. ALBARET ET COLLABORATEURS nota, Hippotragus, Cobus, Taurotragus sur le continent africain (Dinnik et Dinnik, 1954 ;Swart, 1954), à Madagascar (Prodhon et coll., 1968, en Israël (Lengy, 1960), en Iran (Arfaa, 1962), en Sardaigne (Reinhardt, 1969). P. microbothrium diffère de notre Trématode par le nombre d'unités constituant les différents ensembles de muscles circulaires de l'acétabulum.…”

“…Par contre le sporocyste est très différent, il a une forme en V fermé chez l'espèce décrite alors que chez P. microbothrium il est allongé et pré sente des parties renflées séparées par des contrictions accusées (Dinnik et Dinnik, 1954). La morphologie générale de la cercaire ne peut guère nous fournir d'éléments de comparaison.…”