A survey of the presence of digenetic trematode larvae in freshwater snails collected in Bakas, Norzagaray, Bulacan

• Main Author: Nufable, Jhoram F.
• Format: text
• Language: English
• Published: Animo Repository 1997
• Subjects: Snails; Trematoda; Digenea > Larvae
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/1455
• Institution: De La Salle University

Snail samples were obtained from a part of Angat River in Bakas, Norzagaray, Bulacan from June to November of 1996. The freshwater snails identified were namely: Melanoides tuberculata, with the small, smooth variant (=SSV), and large, spiny variant (=LSV), Melanoides granifera, and Ampullaria sp. Each individual snail was weighed, sex was determined, and was examined for the presence of trematode larval infection. Melanoides tuberculata (=LSV), recorded 9 infected snails, having an overall prevalence of 18% with 16.67%, and 25% prevalence for female, and male, respectively. Two cercarial body type were noted in this species the opthalmo-elongate bodied cercariea, with knob-like tails, and eyespots, and the xiphidiocercarial type with ovoidal bodies, with a stylet. The small, smooth variant of M. tuberculata had 11 positive cases, all in female snails, and accounts for 22% overall prevalence. Only one cercarial body type was noted, with spherical to somewhat ovoidal bodies, but without stylet Melanoides granifera had 19 positive for larval infection, with 40.48%, and 25% prevalence of for females, and males, respectively, and overall prevalence of 38%.