Skip to Main Content
Itraconazole treatment reduces Batrachochytrium dendrobatidis prevalence and increases overwinter field survival in juvenile Cascades frogsAuthor(s): B.M. Hardy; K.L. Pope; J. Piovia-Scott; R.N. Brown; J.E. Foley
Source: Diseases of Aquatic Organisms. 112(3): 243-250
Publication Series: Scientific Journal (JRNL)
Station: Pacific Southwest Research Station
Download Publication (199.58 KB)
DescriptionThe global spread of the fungal pathogen Batrachochytrium dendrobatidis (Bd) has led to widespread extirpation of amphibian populations. During an intervention aimed at stabilizing at-risk populations, we treated wild-caught Cascades frogs Rana cascadae with the antifungal drug itraconazole. In fall 2012, we collected 60 recently metamorphosed R. cascadae from 1 of the 11 remnant populations in the Cascades Mountains (CA, USA). Of these, 30 randomly selected frogs were treated with itraconazole and the other 30 frogs served as experimental controls; all were released at the capture site. Bd prevalence was low at the time of treatment and did not differ between treated frogs and controls immediately following treatment. Following release, Bd prevalence gradually increased in controls but not in treated frogs, with noticeable (but still nonsignificant) differences 3 wk after treatment (27% [4/15] vs. 0% [0/13]) and strong differences 5 wk after treatment (67% [8/12] vs. 13% [1/8]). We did not detect any differences in Bd prevalence and load between experimental controls and untreated wild frogs during this time period. In spring 2013, we recaptured 7 treated frogs but none of the experimental control frogs, suggesting that over-winter survival was higher for treated frogs. The itraconazole treatment did appear to reduce growth rates: treated frogs weighed 22% less than control frogs 3 wk after treatment (0.7 vs. 0.9 g) and were 9% shorter than control frogs 5 wk after treatment (18.4 vs. 20.2 mm). However, for critically small populations, increased survival of the most at-risk life stage could prevent or delay extinction. Our results show that itraconazole treatment can be effective against Bd infection in wild amphibians, and therefore the beneficial effects on survivorship may outweigh the detrimental effects on growth.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationHardy, B.M.; Pope, K.L.; Piovia-Scott, J.; Brown, R.N.; Foley, J.E. 2015. Itraconazole treatment reduces Batrachochytrium dendrobatidis prevalence and increases overwinter field survival in juvenile Cascades frogs. Diseases of Aquatic Organisms. 112(3): 243-250.
KeywordsRana cascadae · Chytridiomycosis · Amphibian · Declines
- Assessing Changes in Amphibian Population Dynamics Following Experimental Manipulations of Introduced Fish
- Temperature, hydric environment, and prior pathogen exposure alter the experimental severity of chytridiomycosis in boreal toads
- Factors related to the distribution and prevalence of the fungal pathogen Batrachochytrium dentrobatidis in Rana cascadae and other amphibians in the Klamath Mountains
XML: View XML