Department of Ocean Sciences, Rosenstiel School of Marine & Atmospheric Science, 4600 Rickenbacker Causeway, FL 33149-1098, USA; Institute of Marine Research, Austevoll Research Station, Sauganeset 16, N-5392 Storebø, Norway.
Institute of Marine Research, P.O. Box 1870, Nordnes, 5817 Bergen, Norway.
Ecotoxicol Environ Saf. 2018 Sep 30;160:216-221. doi: 10.1016/j.ecoenv.2018.05.021. Epub 2018 May 26.
Infestations with salmon lice, a parasitic copepod, is a major problem in the salmon farming industry. Teflubenzuron is an in-feed pharmaceutical applied to control lice outbreaks; the standard medication is 10 mg per kg fish per day for seven days. Surveys reveal that teflubenzuron accumulates and persists in the sediment around fish farms and causes deformities and mortality in juvenile European lobster (Homarus gammarus), a species commonly found in the vicinity of salmon farms in Norway. To date, there is no information on sub-lethal effects of teflubenzuron on, for example, behavior. We conducted an experiment to assess possible difference in the shelter seeking behavior of teflubenzuron-exposed (N = 19) vs. not exposed (N = 19) H. gammarus juveniles. The teflubenzuron-exposed juveniles had been given very low concentrations, 1.7 µg per pellet twice per week for 113 days prior to this experiment. The concentration of teflubenzuron was estimated to be less than 1 ng/g lobster when they were tested in the behavior experiment. Animals were placed in a lane with a shelter at one end. Once a lobster had found and entered the shelter, they were repeatedly displaced back to the opposite end of the lane, for a total of 3 repeated runs per animal. Three of the exposed juveniles failed to settle in the shelter, and the remaining teflubenzuron-exposed animals took significantly more time to explore the environment and to find and recognize shelter. Furthermore, exposed lobsters also exhibited slower walking speed compared to the controls. These results demonstrate that teflubenzuron significantly reduces exploratory behavior, learning and activity of juvenile H. gammarus. Thus, exposure to teflubenzuron could increase predation mortality of juvenile lobsters in the wild.
感染鲑虱，一种寄生桡足类动物，是鲑鱼养殖业的主要问题。氟虫脲是一种用于控制虱爆发的饲料药物；标准剂量为每公斤鱼每天 10 毫克，持续七天。调查显示，氟虫脲在鲑鱼养殖场周围的沉积物中积累并持续存在，导致幼年期欧洲龙虾（Homarus gammarus）畸形和死亡，欧洲龙虾是挪威鲑鱼养殖场附近常见的物种。迄今为止，尚无关于氟虫脲对行为等亚致死效应的信息。我们进行了一项实验，以评估暴露于氟虫脲（N=19）和未暴露于氟虫脲（N=19）的 H. gammarus 幼体在寻求庇护行为上可能存在的差异。在进行这项实验之前，氟虫脲暴露的幼体已经接受了非常低的浓度，每周两次给予 1.7µg/丸，共 113 天。当它们在行为实验中进行测试时，氟虫脲的浓度估计低于 1ng/g 龙虾。将动物放置在一条带有一个庇护所的通道中。一旦龙虾找到了并进入庇护所，它们就会被反复移回通道的另一端，每个动物重复 3 次。3 只暴露的幼体未能在庇护所中定居，其余暴露于氟虫脲的动物花费了明显更多的时间来探索环境，并找到和识别庇护所。此外，暴露于氟虫脲的龙虾的行走速度也明显较慢。这些结果表明，氟虫脲显著降低了幼年期 H. gammarus 的探索行为、学习能力和活动能力。因此，暴露于氟虫脲可能会增加野生幼年期龙虾的捕食死亡率。
