Habitat Differences Affect the Nuclear Morphology of the Erythrocytes and the Hepatic Melanin in Leptodactylus Fuscus (Anura) in the Brazilian Cerrado Savanna

Abstract

The sensitivity of anuran to the effects of habitat destruction and contamination has led to a preoccupying global decline in their populations. Morphological biomarkers such as micronuclei and other erythrocyte nuclear abnormalities (ENAs) and the occurrence of hepatic melanin can be used to evaluate the effects of habitat impacts. In the present study, these two procedures were combined for the in situ assessment of the effects of soybean cultivation on the grassfrog, Leptodactylus fuscus. Specimens were also collected from a protected area to provide a control (non-agricultural environment). The frequency of some nuclear abnormalities in the animals from the soybean plantation was much higher than the control, specifically, micronuclei were 3.6 times more frequent, while lobulated nuclei were 3.4 times more frequent, and reniform nuclei, four times more common. The combined analysis of all the ENAs also revealed a frequency approximately 1.4 times higher in the animals from the soybean plantation, in comparison with the protected area. Smaller areas of hepatic melanin were observed in the specimens from the soybean plantation. These results provide further evidence of the sensitivity of anurans to habitat impacts, and indicate that animals found in soybean plantations are susceptible to systematic alterations of the cells.