ABSTRACT: Securing the welfare and maximising the lice removal efficacy of ~60 million cleaner fish used each year on salmonid farms is essential to develop a productive and ethical industry with low salmon lice Lepeophtheirus salmonis levels. We tested whether ballan wrasse Labrus bergylta welfare and lice consumption differed depending upon whether they were acclimatised in cages with either no Atlantic salmon Salmo salar, salmon without lice, or lice-infested salmon, prior to deployment in sea cages. After 1 wk, commercial densities of lice-infested salmon were stocked with the acclimatised wrasse in cages and kept for a further 3 wk. Each week, the number of lice on salmon was counted and a subset of wrasse was sampled for gut contents and physical welfare. Lice occurred less frequently in wrasse guts (6% of all dietary items) compared to caprellid amphipods (76%). Ballan wrasse consumed more lice if they were pre-exposed to lice-infested salmon (mean ± SE = 0.79 ± 0.4 lice) compared to wrasse not pre-exposed to salmon (0.15 ± 0.1 lice, p = 0.003) or wrasse pre-exposed to salmon without lice (0.01 ± 0.09 lice, p = 0.03). This did not affect overall mobile lice loads on salmon, which doubled over the study period regardless of acclimatisation strategy. Decline in condition factor (K) and the increase in specific physical damage over time were not affected by acclimatisation strategy. If welfare can be secured, acclimatisation could be tested on cleaner fish at commercial scales as a strategy to improve biological control agents.

中文翻译：

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适应虱子侵害的鲑鱼可改善鱼虱的清洁消费

摘要：确保福利，并使每年在鲑鱼养殖场使用的约6000万条清洁鱼的虱子清除功效最大化，对于发展鲑鱼虱子Lepeophtheirus鲑鱼水平低的生产性和道德产业至关重要。我们测试了Ballan濑鱼Labrus bergylta的福利和虱子的食用量是否有所不同，具体取决于它们是否适应没有大西洋鲑Salmo salar的网箱，没有虱子的鲑鱼或虱子侵袭的鲑鱼，然后将它们部署在海笼中。1周后，将商业密度的虱子感染的鲑鱼放入笼中，放入适应环境的濑鱼，并再保持3周。每周都要对鲑鱼上的虱子数量进行计数，并抽取一部分濑鱼来检查肠内含量和身体健康。与蛤rel类双足动物（76％）相比，濑鱼肠中的虱子发生频率较低（占所有饮食项目的6％）。与未预先暴露于鲑鱼的鲑鱼（0.15±0.1虱子，p = 0.003）或预先暴露于濑鱼的巴乐藻相比，如果预先暴露于受虱子侵害的鲑鱼（平均值±SE = 0.79±0.4虱子），它们会消耗更多的虱子。到没有虱子的鲑鱼（0.01±0.09虱子，p = 0.03）。这并没有影响鲑鱼的整体移动虱子负荷，无论适应环境如何，在研究期间，鲑鱼的虱子负荷都增加了一倍。K）和随时间变化的特定物理损伤的增加不受驯化策略的影响。如果可以确保福利，则可以在商业规模上对清洁鱼进行适应性测试，以此作为改善生物防治剂的策略。