Toxicidade aguda (LC50) e efeitos comportamentais e morfológicos do formulado comercial Roundup Original® em girinos de Physalaemus cuvieri (anura, leptodactylidae) e Rhinella icterica (anura, bufonidae)

Abstract

The decline of amphibians in the world is increasing and the loss richness is often associated with agricultural areas. The use of pesticides, especially those based on glyphosate is increasing and new formulations are being developed. This study evaluated the acute toxicity of commercial formulated Roundup Original® and behavioral and morphological effects on Physalaemus cuvieri and Rhinella icterica tadpoles. Were used five different concentrations sample and the control test, at time of 48 hours and 96 hours. To P. cuvieri the concentrations used was 0 (control), 3,19 mg/L, 6,36 mg/L, 9,51 mg/L, 12,64 mg/L and 15,75 mg/L solution of 1000 mg/L of glyphosate, and the concentrations used to R. icterica was 0 (control), 4,97 mg/L, 9,90 mg/L, 14,78 mg/L, 19,61 mg/L and 24,39 mg/L solution of 1000 mg/L of glyphosate. To Physalaemus cuvieri the LC5048h was 6,66 mg/L while LC5096h was 7,17 mg/L and to Rhinella icterica the LC5048h was 15,01mg/L and LC5096h was 11,25 mg/L. P. cuvieri proved to be more sensitive to Roundup Original® than R. icterica. Behavioral analyzes was did in survivors of the acute toxicity test and analyzed the swimming, being normal or abnormal. There weren't significant differences in relation to behavioral changes and increased concentrations of Roundup Original® both P. cuvieri as in R. icterica. Morphological analyzes were assessed by malformation of the oral cavity, body, intestinal position (in P. cuvieri only), weight and length. The present work suggests that Roundup Original® was responsible for morphological changes in weight and length of tadpoles of P. cuvieri and R. icterica. It is also suggested that at high exposure time can affect the oral cavity of tadpoles of Physalaemus cuvieri.