Impacts of isolated or mixed Roundup ® Original DI and Boral® 500 SC herbicides on the survival and metamorphosis of Melanophryniscus admirabilis tadpoles

Aquat Toxicol. 2023 Oct 6;264:106715. doi: 10.1016/j.aquatox.2023.106715. Online ahead of print.ABSTRACTThe bufonid species Melanophryniscus admirabilis is restricted to a single location in the southern Atlantic Forest, Brazil. Although the site of occurrence of M. admirabilis is covered with native forest and it is not directly exposed to pesticides application, the area is surrounded by agricultural activity. Our objectives were to evaluate possible alterations in morphological parameters (body mass, snout-vent length, and body index), metamorphosis (time to reach Gosner stages 42, 46 and to complete metamorphosis), and survival of M. admirabilis exposed to isolated Roundup® Original DI (R1: 234 and R2: 2340 µg.L-1 of glyphosate) and Boral® 500 SC, (B1: 130 and B2: 980 µg.L-1 of sulfentrazone) or mixed (R1+B1, R2+B1, R1+B2, R2+B2). Spawns of M. admirabilis were collected in natural lakes in the municipality of Arvorezinha and taken to laboratory cultivation. After the tadpoles acquired free swimming, the animals were acclimated for five days and fed ad libitum. The aquariums were contaminated with herbicides on the sixth day of cultivation, and the animals stayed in these aquariums for four days. Afterwards, the tadpoles were transferred to aquariums with clean water and monitored until metamorphosis (Gosner stage 46), when they were weighed, measured (snout-cloacal length) and cryoeuthanized. We observed no alterations in morphological parameters; however, survival wa...
Source: Aquatic Toxicology - Category: Toxicology Authors: Source Type: research