, 20:901

Agricultural intensity in ovo affects growth, metamorphic development and sexual differentiation in the Common toad (Bufo bufo)


DOI: 10.1007/s10646-011-0658-5

Cite this article as:
Orton, F. & Routledge, E. Ecotoxicology (2011) 20: 901. doi:10.1007/s10646-011-0658-5


Pollution was cited by the Global Amphibian Assessment to be the second most important cause of amphibian decline worldwide, however, the effects of the agricultural environment on amphibians are not well understood. In this study, spawn from Bufo bufo was taken from four sites in England and Wales with varying intensities of arable agriculture. Spawn was either placed in tanks containing aged tap water (ex-situ, five replicates) or in cages at the native site (caged, five replicates). Hatching success, abnormal tadpoles, and forelimb emergence were recorded during the larval stage. Individuals were also sampled at five time points (TP) during development (5-, 7-, 9-, 12-, 15-weeks post-hatch) and analysed for morphological parameters. The thyroids (TP2) and the gonads (TP3,4,5) were also analysed histologically. With the exception of the thyroid histopathology, all analysed endpoints were significantly different between ex-situ individuals reared under identical conditions from the different sites. In addition, intensity of arable agriculture had a negative effect on growth and development. At one site, despite distinct rearing conditions, a high level of intersex (up to 42%) and similar sex ratios were observed in both ex-situ and caged individuals. Taken together, these data suggest that maternal exposure and/or events in ovo had a much larger effect on growth, metamorphic development, and sexual differentiation in B. bufo than the ambient environment. This could have important implications for traditional exposure scenarios that typically begin at the larval stage. Intersex is reported for the first time in European amphibians in situ, highlighting the potential use of distinct populations of amphibians in fundamental research into the aetiology of specific developmental effects in wild amphibians.


Amphibian Pollution Pesticides Herbicides Endocrine disruption Intersex 



Time point


Snout-vent length


Hindlimb length


Forelimb emergence


Dissolved oxygen


Testicular oocyte

Supplementary material

10646_2011_658_MOESM1_ESM.pdf (515 kb)
Supplementary material 1 (PDF 515 kb)

Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Institute for the EnvironmentBrunel UniversityUxbridgeUK
  2. 2.Centre for Toxicology, School of PharmacyUniversity of LondonLondonUK