eCite Digital Repository

Prevalence and intensity of Cardicola spp. infection in ranched southern bluefin tuna and a comparison of diagnostic methods

Citation

Power, C and Evenden, S and Rough, K and Webber, C and Widdicombe, M and Nowak, BF and Bott, NJ, Prevalence and intensity of Cardicola spp. infection in ranched southern bluefin tuna and a comparison of diagnostic methods, Pathogens, 10, (10) Article 1248. ISSN 2076-0817 (2021) [Refereed Article]


Preview
PDF
1Mb
  

Copyright Statement

Copyright 2021 The Authors. Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0) https://creativecommons.org/licenses/by/4.0/

DOI: doi:10.3390/pathogens10101248

Abstract

The parasitic blood flukes Cardicola forsteri and C. orientalis are an ongoing health concern for Southern Bluefin Tuna Thunnus maccoyii (SBT) ranched in Australia. In this study we compared the effect of treatment, company, and ranching year on blood fluke infections in ranched SBT. SBT were sampled during the 2018 and 2019 ranching seasons from praziquantel (PZQ) treated pontoons and untreated pontoons managed by two companies. Severity of infection was diagnosed by several criteria including adult fluke counts from hearts, egg counts from gill filaments and the use of specific quantitative polymerase chain reaction (qPCR) for detection of C. forsteri and C. orientalis ITS-2 DNA in SBT hearts and gills. PZQ treatment remains highly effective against C. forsteri infection. Prevalence and intensity of Cardicola spp. infection was lower in 2019 than 2018 for Company A in treated pontoons at week 12 and week 17 of ranching, and lower for Company A than Company B in untreated pontoons at month 5 of ranching. Results indicate re-infection may be less likely in the environment near Company A pontoons, and consistent years of treatment may have lowered the parasite load in the environment. qPCR demonstrated higher sensitivity when comparing diagnostic methods for C. forsteri in heart, and higher specificity when comparing diagnostic methods for Cardicola spp. in gills. Continuing to monitor blood fluke infections in ranched SBT can help to detect changes in drug efficacy over time and help industry to develop a best practice for treatment.

Item Details

Item Type:Refereed Article
Keywords:Cardicola, bluefin tuna, blood fluke, praziquantel, aquaculture, diagnostics
Research Division:Agricultural, Veterinary and Food Sciences
Research Group:Fisheries sciences
Research Field:Fish pests and diseases
Objective Division:Animal Production and Animal Primary Products
Objective Group:Fisheries - aquaculture
Objective Field:Aquaculture tuna
UTAS Author:Nowak, BF (Professor Barbara Nowak)
ID Code:146938
Year Published:2021
Deposited By:Fisheries and Aquaculture
Deposited On:2021-10-04
Last Modified:2021-11-05
Downloads:0

Repository Staff Only: item control page