温度和联苯菊酯对奇努克鲑（Oncorhynchus tshawytscha）幼鱼回避行为的交互作用的背后机制。
Mechanisms behind interactive effects of temperature and bifenthrin on the predator avoidance behaviors in parr of chinook salmon (Oncorhynchus tshawytscha).
机构信息
Environmental Toxicology Graduate Program, University of California Riverside, Riverside, CA, USA; Department of Environmental Sciences, University of California Riverside, Riverside, CA, USA.
Environmental Toxicology Graduate Program, University of California Riverside, Riverside, CA, USA; Department of Environmental Sciences, University of California Riverside, Riverside, CA, USA.
出版信息
Aquat Toxicol. 2019 Nov;216:105312. doi: 10.1016/j.aquatox.2019.105312. Epub 2019 Sep 19.
Many coastal systems have been experiencing the effects of non-chemical and chemical anthropological stressors through respective increases in surface water temperatures and rainstorm-derived runoff events of pyrethroid pesticide movement into waterways such as the San Francisco Bay-Delta. Salmonid populations in the Bay-Delta have been dramatically declining in recent decades. Therefore, the aim of this study was to investigate the interactive effects of bifenthrin, a pyrethroid insecticide, and increasing water temperatures on targeted neuroendocrine and behavioral responses in Chinook salmon (Oncorhynchus tshawytscha) parr (10- month post-hatch). Parr were reared at 11 °C, 16.4 °C, or 19 °C for 14 days and, in the final 96 h of rearing, exposed to nominal concentrations of 0, 0.15, or 1.5 μg/L bifenthrin. A predatory avoidance Y-Maze behavioral assay was conducted immediately following exposures. Parr were presented a choice of clean or odorant zones, and locomotive behavior was recorded. Thyroid hormones (T3 and T4), estradiol, and testosterone were quantified within plasma using ELISAs, and the expression of brain hormone and dopamine receptor genes were also evaluated by qPCR. Brain dopamine levels were analyzed by LC/MS. No significant changes were observed in brain transcripts or plasma hormone concentrations with bifenthrin or increasing temperature. However, temperature did significantly lower brain dopamine levels in fish reared at 19 °C compared to 11 °C controls, but was unaltered by bifenthrin treatment. In contrast, parr reared at 11 °C and exposed to 1.5 μg/L bifenthrin spent significantly less time avoiding a predatory odorant compared to vehicle controls reared at 11 °C. The 16.4 °C and 1.5 μg/L-treated fish spent significantly more time in the neutral arm compared to the odorant and clean arms, as well as spending significantly less time in the clean arm compared to the 11 °C control fish. These results suggest that the interaction of temperature and bifenthrin may be adversely impacting predator-avoidance behavior, which may not be related to dopaminergic responses.
许多沿海系统都受到非化学和化学人为压力因素的影响，这些因素导致地表水温升高，以及暴雨导致的拟除虫菊酯类杀虫剂进入水道，如旧金山湾-三角洲地区。最近几十年来，湾-三角洲地区的鲑鱼数量急剧下降。因此，本研究的目的是研究在 11°C、16.4°C 和 19°C 下分别饲养 14 天的虹鳟（Oncorhynchus tshawytscha）幼鱼（孵化后 10 个月）中，拟除虫菊酯杀虫剂联苯菊酯和水温升高对其神经内分泌和行为反应的交互影响。在最后 96 小时的饲养期内，幼鱼暴露于 0、0.15 或 1.5μg/L 的联苯菊酯浓度下。暴露后立即进行捕食回避 Y 型迷宫行为测试。幼鱼被给予清洁区或气味区的选择，记录其运动行为。使用 ELISA 法测定血浆中的甲状腺激素（T3 和 T4）、雌二醇和睾酮，并用 qPCR 评估脑激素和多巴胺受体基因的表达。通过 LC/MS 分析脑多巴胺水平。联苯菊酯或温度升高均未导致幼鱼脑转录物或血浆激素浓度发生显著变化。然而，与 11°C 对照组相比，19°C 下饲养的鱼的脑多巴胺水平显著降低，但联苯菊酯处理并未改变这一结果。相比之下，在 11°C 下饲养并暴露于 1.5μg/L 联苯菊酯的幼鱼在回避捕食者气味方面花费的时间明显少于在 11°C 下饲养的对照鱼。与 16.4°C 和 1.5μg/L 处理的鱼相比，11°C 对照组的鱼在中性臂花费的时间显著减少，而在气味臂和清洁臂花费的时间显著增加，与 11°C 对照组的鱼相比，在清洁臂花费的时间也显著减少。这些结果表明，温度和联苯菊酯的相互作用可能会对鱼类的捕食回避行为产生不利影响，而这种影响可能与多巴胺反应无关。
Zotero 插件