TỈ LỆ NHIỄM ẤU TRÙNG SÁN LÁ SONG CHỦ CERCARIAE TRÊN ỐC TRONG KÊNH CẤP NƯỚC TRỰC TIẾP CHO AO NUÔI CÁ Ở HUYỆN BÌNH CHÁNH, THÀNH PHỐ HỒ CHÍ MINH, VIỆT NAM

Abstract

A study on the rate of infection of trematodes’ cercariae larvae on snails from 16 canals supplying water directly to fishponds in Binh Chanh District, Ho Chi Minh City was carried out in March 2023 (the dry season) and August 2023 (the wet season). A 25x25cm dredge was used to scrape the pond bottom 10cm deep from 1.0 m out from the pond bank to collect snails. A total of three such samples were taken at three different locations in each canal with a distance of 100m between the two sampling points. Four morphotypes of cercariae recovered from snails were identified by the morphological method including Xiphidio, Echinostoma, Transversotrema, and Furcocercous cercariae. The trematode prevalence in snails was 10.4%, 6.7%, 5.3%, and 3.3% in Indoplanorbis exustus, Melanoides tuberculata, Bithynia siamensis and Lymnaea viridis, respectively. The other five snail species free from cercariae were Pomacea canaliculata, Pila ampullacea, Thiara scabra, Filopaludina sumatrensis, and Filopaludina martensi martensi. Further research on the trematode prevalence of snails in canals supplying water directly to fishponds around the year in Binh Chanh District needs to be done to identify the seasonal diversity of cercariae in snails to be controlled, and this can contribute to the development of clean aquaculture.