ABSTRACT: Planktonic salmon louse Lepeophtheirus salmonis salmonis larvae produced at salmon farms spread to and infect both wild and farmed salmonids. Understanding and forecasting the production and distribution of these larval stages from farms is critical to aquaculture management. However, model forecasts are based on available data and therefore include parameters with limited empirical support. This investigation examined salmon louse fecundity with a focus on batch egg clutch size by collecting lice from farmed Atlantic salmon Salmo salar at multiple farms and from wild Atlantic salmon and sea trout S. trutta captured at field sites throughout Norway. The data were analyzed with mixed effects models and total length of female lice was identified as the primary determinant of clutch size. Further analysis revealed that female louse total length is partially explained by temperature at sampling. However, if the temperature at sampling is spatially or temporally disconnected from rearing temperature, it may not be possible to predict the total length of a louse using temperature. The fecundity investigation further found that 66% of female lice on farmed salmon were sexually mature, and 10% of these were not egg-bearing. In comparison, 73% of adult female lice on sea trout were sexually mature, and 40% of these were not egg-bearing. Our results indicate that salmon louse production forecasts would be improved by incorporating female louse sexual maturity and a clutch size parameter that is related to total length of female lice.

中文翻译：

---

使用多年田间样本解开鲑鱼虱 Lepeophtheirus salmonis 繁殖力的关键驱动因素

摘要：鲑鱼养殖场生产的浮游鲑鱼虱Lepeophtheirus salmonis salmonis幼虫传播并感染野生和养殖鲑鱼。了解和预测养殖场这些幼体阶段的生产和分布对于水产养殖管理至关重要。然而，模型预测是基于可用数据，因此包括经验支持有限的参数。这项调查通过从多个养殖场的养殖大西洋鲑鱼Salmo salar以及野生大西洋鲑鱼和海鳟鱼S. trutta收集虱子，检查了鲑鱼虱子的繁殖力，重点是批量产卵大小在整个挪威的现场捕获。使用混合效应模型对数据进行分析，雌性虱子的总长度被确定为窝数大小的主要决定因素。进一步的分析表明，雌性虱子的总长度部分是由采样时的温度来解释的。但是，如果采样时的温度在空间或时间上与饲养温度脱节，则可能无法使用温度预测虱子的总长度。繁殖力调查进一步发现，养殖鲑鱼身上66%的雌性虱子性成熟，其中10%不产卵。相比之下，海鳟鱼身上 73% 的成年雌性虱子性成熟，其中 40% 没有卵子。