ABSTRACT: Sea lice Lepeophtheirus salmonis are marine copepods that are the primary parasitic threat to Atlantic salmon Salmo salar aquaculture. Prior to infecting a host, L. salmonis embryos and larvae rely entirely on maternally derived lipid reserves, offering a unique lens for investigation of energetic trade-offs and reproductive investment. In the current study, we combined histology and image processing to assess L. salmonis embryo size, number of lipid droplets per egg, and lipid area across monthly collections (2018-2019) from S. salar farms in Maine, USA. Results indicate consistent embryo areas from season to season, peak lipid metrics in May, and minima in lipid quantities from October-December. Therefore, gravid females appear to invest the highest lipid levels in their embryos under biologically favorable conditions, when future larvae may thrive in the plankton and infection typically begins to surge on farms. In contrast, maternal lice likely allocate proportionately more energy into metabolizing their own lipid stores for vertical migration and survival through the winter. A detailed understanding of seasonal lipid reserves is fundamental for the improvement of infection models. These indicators at the earliest developmental stage partially encode recruitment of subsequent planktonic larvae, enabling unique forecasting potential to inform pest management on salmon farms.

中文翻译：

---

从鲑鱼养殖场收集的海虱Lepeophtheirus鲑鱼的胚胎大小和脂质储备的季节性变化

摘要：海虱Lepeophtheirus鲑鱼是海洋co足类动物，是大西洋鲑Salmo盐沼养殖的主要寄生虫威胁。在感染宿主之前，鲑鱼乳杆菌的胚和幼虫完全依靠母体来源的脂质储备，为研究能量平衡和生殖投资提供了独特的视角。在目前的研究中，我们结合组织学和图像处理，以评估L.鲑从胚胎大小，每个蛋脂滴的数量，以及跨每月集合脂质区域（2018 - 2019年）S.鲑美国缅因州的农场。结果表明不同季节的胚胎面积一致，5月的血脂指标达到峰值，10月至12月的血脂量最低。因此，当未来的幼虫可能在浮游生物中繁盛并且感染通常在农场中开始流行时，妊娠雌性动物似乎在生物学上有利的条件下将最高的脂质水平投入到其胚胎中。相比之下，母虱可能会按比例分配更多的能量来代谢自己的脂质储藏，从而在整个冬季进行垂直迁移和生存。对季节性脂质储备的详细了解是改善感染模型的基础。这些指标在最早的发展阶段部分编码随后浮游幼虫的募集，从而使独特的预测潜力可为鲑鱼养殖场的有害生物管理提供信息。