TitleA method for collecting eggs of Pseudocapillaria tomentosa (Nematoda: Capillariidae) from zebrafish Danio rerio and efficacy of heat and chlorine for killing the nematode's eggs.
Publication TypeJournal Article
Year of Publication2017
AuthorsMartins, ML, Watral, V, Rodrigues-Soares, JP, Kent, ML
JournalJ Fish Dis
Date Published2017 Feb
KeywordsAnimals, Antinematodal Agents, Aquaculture, Chlorine, Dose-Response Relationship, Drug, Enoplida Infections, Fish Diseases, Hot Temperature, Ovum, Trichuroidea, Zebrafish

Pseudocapillaria tomentosa is a common pathogen of zebrafish (Danio rerio) in research facilities. We developed a method to collect and concentrate the nematode eggs using a modified sugar centrifugation method and documented their normal development. Embryonating stages with blastomere formation followed by elongation of the embryo prior to larva formation cumulated in developed larvae inside the eggs and hatching after 5-10 day. We then evaluated the efficacy of heat and chlorine to kill them based on a larva development assay. Eggs were exposed to 40, 50, 60 °C for 30 min and 1 h. Chlorine treatment was performed at 100, 250, 500, 1000, 3000 and 6000 ppm for 10 min. Samples exposed to 40 °C for 30 min or 1 h showed incidences of larvated eggs similar to controls. In contrast, no larvation occurred with eggs exposed to either 50 or 60 °C for 30 min or 1 h. Remarkably, in repeated assays, samples exposed to low doses of chlorine (100, 250, 500 and 1000 ppm for 10 min) showed significantly higher incidence of larvation than controls. Eggs treated with 3000 ppm for 10 min did not develop larvae, and no eggs were found after 6000 ppm treatment.

Alternate JournalJ Fish Dis
PubMed ID27334246
PubMed Central IDPMC5182181
Grant ListP40 OD011021 / OD / NIH HHS / United States
R24 OD010998 / OD / NIH HHS / United States