Development and transmission of Gyrinicola batrachiensis (Walton, 1929) Adamson, 1981 (Pharyngodonidae: Oxyuroidea)

Abstract

Individual female Gyrinicola batrachiensis from tadpoles produce thin-shelled larvated eggs and thick-shelled eggs containing embryos in an early stage of cleavage. Larvae in thin-shelled eggs hatched soon after deposition and survived for less than 1 h in aged tap water, pond water, or diluted buffer. Results presented herein show that thin-shelled eggs are autoinfective whereas thick-shelled eggs are transmission agents. Thick-shelled eggs isolated from natural infections in Rana clamitans, Rana pipiens, and Bufo americanus were infective to tadpoles of R. clamitans, R. sylvatica, Pseudacris triseriata, and B. americanus but not to transformed anurans. All worms recovered from tadpoles experimentally infected with eggs from natural infections in B. americanus were females and only 15% of worms examined from tadpoles experimentally infected with eggs from natural infections in R. clamitans were males. Development of G. batrachiensis was studied in experimentally infected R. clamitans held at 20 and 25 °C. Development was more rapid at 25 °C and males developed more rapidly than females at both temperatures. Adult males were first observed after 9 days (25 °C) and 16 days (20 °C) and adult females were first observed after 12 days (25 °C) and 19 days (20 °C).