First evidence of the effects of agricultural activities on gonadal form and function in Rhinella fernandezae and Dendropsophus sanborni (Amphibia: Anura) from Entre Ríos Province, Argentina

LAURA C. SANCHEZ, RAFAEL C. LAJMANOVICH, PAOLA M. PELTZER, ADRIANA S. MANZANO, CELINA M. JUNGES, ANDRÉS M. ATTADEMO

ACTA HERPETOLOGICA

FIRENZE UNIV PRESS

Año: 2014 vol. 9 p. 75 - 88

1827-9635

The relationship between male gonadal abnormalities and habitats with different degrees of agricultural activities was quantified in two anuran species, Rhinella fernandezae and Dendropsophus sanborni. The study sites were selected along a gradient of increasing agricultural land use in south-western Entre Ríos province (Argentina): an agroecosystem, a natural wetland (a non-agricultural site adjacent to monocultures zones), and a natural forest (with no association with agriculture). Field surveys were performed to manually capture R. fernandezae and D. sanborni in each environment. A scaled mass index (MI) was evaluated for each animal. Specimens of R. fernandezae from the agroecosystem and the natural wetland site presented poorly developed seminiferous tubules, lower testicular volume, and lower number of seminiferous tubules, primary spermatogonia, and spermatids compared with specimens from the natural forest site. Additionally, we observed fewer primary spermatocytes in the agroecosystem group than in the natural forest group. Individuals of D. sanborni from the agroecosystem and the natural wetland site presented poorly developed tubules, higher proportions of irregularly shaped testes, and reduced number of primary and secondary spermatogonia compared with specimens from natural forest sites. Consequently, the affected anurans likely have reduced reproductive success. We suggest that agrochemical use may be associated with decreased testicular development and function in both R. fernandezae and D. sanborni occurring in agroecosystems and nearby environments. Buffer zones are needed to prevent contamination, preserve wildlife, and enhance the conservation value of pristine natural forests.