Department of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, SK, S7N 5E2, Canada.
Department of Veterinary Biomedical Sciences, University of Saskatchewan, 52 Campus Drive, Saskatoon, SK, S7N 5B4, Canada.
Arch Environ Contam Toxicol. 2019 Jul;77(1):62-67. doi: 10.1007/s00244-019-00604-1. Epub 2019 Mar 5.
Selenium (Se) is an essential micronutrient for animals and yet becomes toxic with only a small increase in concentration. Toxicological studies have reported various effects of Se on fishes, including developmental impacts and deformities of the musculature and sensory systems. This paper investigates the impact of sublethal concentrations of Se on the ability of the Fathead Minnow (Pimephales promelas) to perform escape responses, a routine behaviour important to predator-prey dynamics. Predation is among the strongest evolutionary driving forces in nature. Changes to this dynamic can have effects that cascade through the ecosystem. We used responses to mechanical and visual stimuli to determine the impact of environmentally relevant concentrations of dietary selenomethionine on the behaviour of minnows. Latency to respond to the stimulus and kinematic performance were assessed. Our results indicated that there was no significant effect of selenomethionine on either the visual response to a threat or burst swimming behaviours of the fast-start response in minnows. Levels of Se in tissues approached that of tissue-specific guidelines set by regulatory bodies across North America. This suggests that current regulations are adequately protecting this key component of predator avoidance in Fathead Minnows.
硒（Se）是动物必需的微量元素，但浓度只要稍有增加就会变得有毒。毒理学研究报告了硒对鱼类的各种影响，包括肌肉和感觉系统的发育影响和畸形。本文研究了亚致死浓度的硒对食蚊鱼（Pimephales promelas）逃避反应能力的影响，逃避反应是一种对捕食者-猎物动态很重要的常规行为。捕食是自然界中最强的进化驱动力之一。这种动态的变化可能会对生态系统产生级联效应。我们使用对机械和视觉刺激的反应来确定膳食硒代蛋氨酸的环境相关浓度对小鱼行为的影响。评估了对刺激的反应潜伏期和运动学表现。我们的结果表明，硒代蛋氨酸对小鱼对威胁的视觉反应或快速启动反应的爆发游泳行为没有显著影响。组织中的硒水平接近北美监管机构设定的组织特异性指南。这表明，目前的法规充分保护了食蚊鱼逃避捕食者的这一关键组成部分。
