Cercarial Infections of Freshwater Snail Genus Brotia in Thailand

Pinanrak Pratumsrikajorn, Suluck Namchote, Dusit Boonmekam, Tanyarat Koonchornboon, Matthias Glaubrecht, Duangduen Krailas


     Freshwater snail genus Brotia is susceptible to trematode infections. In this study, Brotia spp. were collected from 61 localities in Thailand during 2004-2009 and 2013-2015 (to collect those in all localities distributed in Thailand, they have to be collected in two time frames). The samples were collected by hand picking and scooping methods based on counts per unit of time. A total of 13,394 snails were collected and identified into 16 species. They were B. armata, B. binodosa, B. citrina, B. costula, B. dautzenbergiana, B. henriettae, B. insolita, B. manningi, B. microsculpta, B. pagodula, B. paludiformis, B. peninsularis, B. pseudosulcospira, B. solemiana, B. subgloriosa, and B. wykoffi. Cercariae were investigated using shedding and crushing methods. Three species of Brotia had found the cercarial infections, they were B. costula, B. dautzenbergiana, and B. wykoffi. The overall infection rate was 0.20% (27/13,394). The cercariae were categorized into two types and three species. The first type was Xiphidiocercariae with one species, Loxogenoides bicolor Kaw, 1945. It was found in those three species of infected snails. The infection rate was 0.18% (24/13,394). The second type was Parapluerophocercus cercariae with two species. The first species was Stictodora tridactyla Martin & Kuntz, 1955. The infection rate was 0.007% (1/13,394). It was found in B. costula. The second species was H. pumilio Looss, 1899. The infection rate was 0.014% (2/13,394). It was found in B. costula and
B. dautzenbergiana.

Key Words: Cercarial infection; Freshwater snail; Brotiaspp.

Full Text: PDF