Rendiconti Lincei

, Volume 28, Issue 4, pp 687–692 | Cite as

Validation and cost-effectiveness of an alternative method to quantify Batrachochytrium dendrobatidis infection in amphibian samples using real-time PCR

  • Stefano Canessa
  • Marco Maggesi
  • Sebastiano Salvidio
  • Elena Grasselli


The chytrid fungus Batrachochytrium dendrobatidis (Bd) is considered one of the main causes of amphibian declines worldwide. Detection of Bd infection relies on both histological and molecular techniques, but only quantitative real-time PCR (qPCR) provides quantitative information on intensity of infection. To quantify Bd infection, Boyle et al. (2004) developed a standard method using TaqMan qPCR assay: however, the high costs of this method can hinder its applicability for studies with limited resources. Starting from the method by Boyle et al. (2004), we set up and fully validated a qPCR assay based on modified primers and SYBR Green chemistry. The modified SYBR Green has high sensitivity and specificity, as well as the ability to quantify Bd infection loads as well as the standard TaqMan qPCR, but it is more than 60% cheaper. This is obtained both by intrinsic cost-effectiveness of the SYBR Green technique and by reducing reaction volumes of qPCR. Therefore, this modified qPCR assay constitutes a cheaper molecular method to quantify Bd in amphibians.


Chytridiomycosis Amphibian disease Infection loads Monitoring qPCR Cost evaluation 



We thank Trenton Garner for providing the Bd standards, Marco Giovine for reading and commenting a preliminary draft, Frank Pasmans, An Martel, and Giulia Tessa for the useful discussion. SC is supported by the Research Foundation Flanders (FWO). This work was also supported by FRA2016 from University of Genoa.


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Copyright information

© Accademia Nazionale dei Lincei 2017

Authors and Affiliations

  1. 1.Dipartimento di Scienze della Terra, dell’Ambiente e della Vita (DISTAV)The University of GenoaGenoaItaly
  2. 2.Istituto Nazionale Biostrutture e BiosistemiRomeItaly
  3. 3.Department of pathology, bacteriology and avian diseases, Faculty of Veterinary MedicineGhent UniversityMerelbekeBelgium

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