Roundup® is one of the most widely marketed glyphosate-based herbicides in the world. There are many different formulations of this brand that differ from each other in glyphosate concentration, salts and adjuvants, including surfactants, which are labelled as “inert” compounds. Several studies have shown that these formulations are highly toxic to fish, even compared with pure glyphosate. However, mechanisms underlying this toxicity are not fully understood. In this context, this study evaluated the effects of exposure to Roundup Original® (RO), Roundup Transorb® (RT), and Roundup WG® (RWG) on the behavioural patterns of the livebearer Jenynsia multidentata. This fish naturally inhabits agricultural areas in southern Brazil and Argentina where glyphosate is used extensively. In the experiment, animals were exposed to the herbicides for 96 h, at the environmentally relevant concentration of 0.5 mg/L of glyphosate. Swimming performance, anxiety, aggressiveness, long-term memory and male sexual activity were recorded. The formulation RWG negatively affected swimming performance, thigmotaxia and long-term memory consolidation. Conversely, RT reduced the sexual performance of males. These results confirm that Roundup® formulations are extremely harmful and also that they have different targets of toxicity, affecting behaviours that are essential for fish survival.

Roundup® 是世界上销售最广泛的草甘膦除草剂之一。该品牌有许多不同的配方，在草甘膦浓度、盐类和助剂（包括表面活性剂）方面彼此不同，这些剂型被标记为“惰性”化合物。多项研究表明，即使与纯草甘膦相比，这些制剂对鱼类也具有剧毒。然而，这种毒性的机制尚不完全清楚。在此背景下，本研究评估了接触农达 Original® (RO)、农达 Transorb® (RT) 和农达 WG® (RWG) 对活体Jenynsia multidentata行为模式的影响。这种鱼自然栖息在巴西南部和阿根廷广泛使用草甘膦的农业地区。在实验中，动物接触除草剂 96 小时，环境相关浓度为 0.5 mg/L 草甘膦。记录游泳表现、焦虑、攻击性、长期记忆和男性性活动。 RWG 配方对游泳表现、触动性和长期记忆巩固产生负面影响。相反，放疗会降低男性的性能力。这些结果证实农达®配方极其有害，而且它们具有不同的毒性目标，影响鱼类生存所必需的行为。