To avoid being preyed, organisms must be able to identify predatory threats by sensing molecules released by predators (kairomones), and to employ effective strategies to prevent detection by predators. Furthermore, in the wild, organisms are also exposed to chemicals that may alter their behavioral traits, such as neuroactive pharmaceuticals. Considering the co-occurrence of both types of chemicals, their possible interaction needs to be studied. To address this topic, the aim of this study was to verify the effects of fish kairomone (FK - a chemical associated to putative predation by fish) and chlorpromazine (CPZ - neuroactive pharmaceutical drug, environmental contaminant), isolated and in combination, in different functional endpoints of Daphnia magna, such as oxygen consumption, feeding rate, behavior and reproduction. Among these endpoints, oxygen consumption was only affected by the combination of compounds (FK + CPZ). On the other hand, feeding rate was affected by all treatments, being lower than control. For life history traits and phototactic behavior, the effects of FK predominated over the ones caused by CPZ exposure, incrementing the reproductive output of females, leading to greater population growth rates and increasing negative phototactic behaviour.

中文翻译：

---

大型蚤对鱼类海洛酮和氯丙嗪暴露的反应。

为了避免被捕食，生物必须能够通过感知食肉动物（海洛酮）释放的分子来识别食肉动物威胁，并采取有效策略来防止被食肉动物发现。此外，在野外，生物体也接触可能改变其行为特征的化学物质，例如神经活性药物。考虑到两种化学物质同时存在，需要研究它们可能的相互作用。为了解决这个问题，本研究的目的是验证分离和组合使用的鱼卡洛莫酮（FK-一种与鱼类推测的捕食相关的化学物质）和氯丙嗪（CPZ-神经活性药物，环境污染物）的作用。大型蚤（Daphnia magna）的功能性终点，例如耗氧量，进食速度，行为和繁殖。在这些端点中，耗氧量仅受化合物（FK + CPZ）的组合影响。另一方面，喂食率受所有处理的影响，低于对照组。对于生活史特征和光战术行为，FK的影响比CPZ暴露所引起的影响要大，增加了女性的生殖产量，导致人口增长率更高，并且增加了负的光战术行为。